KX Riders

Maintenance & Technical => KX500 Original => Topic started by: stewart on September 08, 2009, 02:21:46 PM

Title: a working compresion release is here
Post by: stewart on September 08, 2009, 02:21:46 PM
if you dont see this in the engine mod section there is a working compresion release set up for the k5.it makes a high comprsion motor start like a pussy cat or a 125  larry wiechman from this site did this mod on one of my high compresion heads great job and works even better
Title: Re: a working compresion release is here
Post by: KXcam22 on September 08, 2009, 05:06:24 PM
Stewart,
  That is nice work.  I sure like that one better than the one that goes in the cylinder wall.  Is there a machining spot in the water jacket or did he create a passage thru the water jacket. Cool. Thats more like my old euro bikes that had a 2nd plug hole so you could run a compression release in the cylinder head. Cam.
Title: Re: a working compresion release is here
Post by: stewart on September 08, 2009, 10:58:26 PM
there is no machining in the water jacket...much better than the cylinder with a hole set up
Title: Re: a working compresion release is here
Post by: RoostDaddy on September 09, 2009, 01:52:56 AM
I'd have to agree with both of you, that I like this alot better than the idea of running one into the cylinder.  Looks like some clean work too.  I guess I'll be the first to say it: Any price yet, Larry?
Title: Re: a working compresion release is here
Post by: Motorrad on September 09, 2009, 03:05:16 AM
Anyone figure out how to make one work with a desert tank yet?
Title: Re: a working compresion release is here
Post by: gwcrim on September 09, 2009, 04:25:46 AM
Yeah........... where were you guys with this last year when I had a big old hole bored in my jug???????   :-( :-( :-( :-(
Title: Re: a working compresion release is here
Post by: serafin on September 09, 2009, 09:50:43 AM
Stewart show us a picture of the top and side of the head.

Serafin
Title: Re: a working compresion release is here
Post by: Larry Wiechman on September 09, 2009, 11:18:41 AM
Anyone figure out how to make one work with a desert tank yet?

 I knew that was coming. That's a good question!
 
 I don't have one locally to look at. Can you send me clear, closeup views of all sides of the head/tank area?
 
Larry
Title: Re: a working compresion release is here
Post by: muleman on September 09, 2009, 12:17:22 PM
Larry I sent you a e-mail.

                                I have the clarke 3.9 gal and I have room on the kick starter side by the head stay.
Title: Re: a working compresion release is here
Post by: Motorrad on September 09, 2009, 04:06:34 PM
Anyone figure out how to make one work with a desert tank yet?

 I knew that was coming. That's a good question!
 
 I don't have one locally to look at. Can you send me clear, closeup views of all sides of the head/tank area?
 
Larry

Well I guess the real question would be.... can the compression release be placed anywhere on the Head that is between a stud and water passage?

If that is the case, Us desert tank guys could hang them off the back of the head... and just have to reach for them (yet another inconvinience to add to the list of deasert tanks)
Title: Re: a working compresion release is here
Post by: muleman on September 10, 2009, 09:34:57 AM
I sent Larry some pics. I am pretty sure you can put it on the kick start side ,back by the head stay. I have the big 3.9 clarke and it blocks everything. Also the choke on the 44mm lectron is on the kick side any way.
Title: Re: a working compresion release is here
Post by: Larry Wiechman on September 10, 2009, 10:47:44 AM
Muleman,
 Great photos, looks like it will work. Is that a Goodson valve? Nice piece, looks like it's all stainless. Might be a bit longer than the saw units.
 
Larry
Title: Re: a working compresion release is here
Post by: BDI on September 10, 2009, 11:47:50 AM
I never thought I could be sold on the comp release. Who ever it was that came up with that is a real thinker. I like it and I would have one on my bike for sure.
Title: Re: a working compresion release is here
Post by: Motorrad on September 10, 2009, 11:55:17 AM
I like the idea of having it behind the head as it will makE it hidden.  Making me look all that more manly when my budys try to start it without one. 
Title: Re: a working compresion release is here
Post by: DoldGuy on September 10, 2009, 12:02:50 PM
Unless one of your Buddies happen to be our member BennieBen :-D
Title: Re: a working compresion release is here
Post by: Larry Wiechman on September 10, 2009, 12:50:35 PM
I like the idea of having it behind the head as it will makE it hidden.  Making me look all that more manly when my budys try to start it without one. 

Start it with your arm and be a real hero. :evil:
Title: Re: a working compresion release is here
Post by: Johnniespeed on September 10, 2009, 01:51:41 PM
Could someone post more pictures of this. I would love to install one on my Isetta, since the electric starter is very  weak and the compression is at 7-1. This release would allow me to boost the compression way up.
 Thanks in advance. John
Title: Re: a working compresion release is here
Post by: muleman on September 10, 2009, 01:56:52 PM
I like the idea of having it behind the head as it will makE it hidden.  Making me look all that more manly when my budys try to start it without one. 

Start it with your arm and be a real hero. :evil:
  yeah the valve is all ss. I got it from a guy that does them on the cr500's. He just put one in a cr500 for my buddy and it kick so easy I can use my arm lol.
 Any idea how much to install.
Title: Re: a working compresion release is here
Post by: muleman on September 10, 2009, 02:11:18 PM
This is the kind they use on the old kick harleys
(http://i237.photobucket.com/albums/ff25/muleman750/decomp.jpg)
(http://i237.photobucket.com/albums/ff25/muleman750/decomp1.jpg)
(http://i237.photobucket.com/albums/ff25/muleman750/decomp2.jpg)
(http://i237.photobucket.com/albums/ff25/muleman750/decomp3.jpg)
Title: Re: a working compresion release is here
Post by: stewart on September 12, 2009, 05:00:49 AM
ran compression release today no problems after a mile wide open sevral times
Title: Re: a working compresion release is here
Post by: Johnniespeed on September 12, 2009, 06:36:46 AM
Do you manually switch it from start mode to run mode, or is it automatic ?
 Who sells these ?
 John
Title: Re: a working compresion release is here
Post by: stewart on September 12, 2009, 06:51:59 AM
just push it in then when the motor starts it auto seals ..very simple
Title: Re: a working compresion release is here
Post by: Larry Wiechman on September 12, 2009, 09:06:33 AM
ran compression release today no problems after a mile wide open sevral times

Looks like we're good to go. I just ordered 12 valves, they should be here in about 4 days. Cost to modify your head will be $125 + shipping (about $7), complete with valve, ready to bolt on the bike.
 
Anyone interested?
 
Larry Wiechman
6222 Elevator Rd.
Roscoe, IL  61073
815-623-8940
wiechman@charter.net
Title: Re: a working compresion release is here
Post by: DoldGuy on September 12, 2009, 09:50:09 AM
Me :-D
Title: Re: a working compresion release is here
Post by: Motorrad on September 12, 2009, 10:22:42 AM
Me once I figure out where I can put it to clear the tank
Title: Re: a working compresion release is here
Post by: Larry Wiechman on September 12, 2009, 10:32:55 AM
Me once I figure out where I can put it to clear the tank

Muleman is going to be the test case for the big tank version. Look at his pictures above, is it the same setup you have?
Title: Re: a working compresion release is here
Post by: slow600 on September 12, 2009, 11:11:00 AM
if this will work with the big clarke tank then im in for sure. which tank do you have muleman? mine the 3.9 gallon.
Title: Re: a working compresion release is here
Post by: Motorrad on September 12, 2009, 11:23:49 AM
Me once I figure out where I can put it to clear the tank

Muleman is going to be the test case for the big tank version. Look at his pictures above, is it the same setup you have?

nope I run a zip-Ty tank and pipe
Title: Re: a working compresion release is here
Post by: Larry Wiechman on September 12, 2009, 11:50:07 AM
Quote
nope I run a zip-Ty tank and pipe

(http://i881.photobucket.com/albums/ac11/LJW197/DECOPM%20TEST/BigTank5.jpg)
 
Will the area marked with the red dot work for you?
Title: Re: a working compresion release is here
Post by: slow600 on September 12, 2009, 12:36:17 PM
figured out that is same tank as me. red dot on mulemans would work perfect for mine
Title: Re: a working compresion release is here
Post by: Larry Wiechman on September 12, 2009, 01:04:19 PM
figured out that is same tank as me. red dot on mulemans would work perfect for mine

 You owe Muleman a beer. Maybe two. :-D
Title: Re: a working compresion release is here
Post by: Motorrad on September 12, 2009, 03:43:17 PM
Not my bike... but the best (Pipe side) pictures I have found....
http://www.kxriders.com/forums/index.php/topic,4930.0.html

as stewart has my motor and pipe.. I have no idea where I can stuff one and have access.. its all speculation

Now since I will have a Batt on the bike due to the Dual sport kit. I was thinking maby one of these would work... just hook to the horn button or somthing on the controlls

http://cgi.ebay.com/ebaymotors/Harley-Davidson-Automatic-Compression-Release-28861-07A_W0QQitemZ110429005277QQcmdZViewItemQQptZMotorcycles_Parts_Accessories?hash=item19b614e5dd&_trksid=p4506.c0.m245
Title: Re: a working compresion release is here
Post by: muleman on September 14, 2009, 12:41:18 PM
I have the 3.9 gal clarke tank
Title: Re: a working compresion release is here
Post by: Larry Wiechman on September 14, 2009, 03:05:58 PM
 This past weekend I built some tooling and fixtures for the compression release modification. Then, tried out the process on my '89 head.
(http://i881.photobucket.com/albums/ac11/LJW197/DECOPM%20TEST/DSCN0676.jpg)
(http://i881.photobucket.com/albums/ac11/LJW197/DECOPM%20TEST/DSCN0677.jpg)
Title: Re: a working compresion release is here
Post by: serafin on September 14, 2009, 03:53:56 PM
Beautiful work Larry.  For us guys that run a large tank IMS, Clark, it looks like we're going to need the unit on the right side of the head. Any problem with that?  I was thinking their might be room on the left side if you were able to machine the unit to attach vertically sort of like a street L.  One last question what valve were you going to use?  The chain saw version or the other "Harley" version? 

Thanks

Serafin
Title: Re: a working compresion release is here
Post by: muleman on September 15, 2009, 11:52:44 AM
(http://i237.photobucket.com/albums/ff25/muleman750/head2.jpg)
(http://i237.photobucket.com/albums/ff25/muleman750/head1.jpg)
I made a bung and going to use the 2mm drill bit as a pin so it doesn't move when It is welded. (http://i237.photobucket.com/albums/ff25/muleman750/head.jpg)
Title: Re: a working compresion release is here
Post by: muleman on September 15, 2009, 11:59:22 AM
Sorry these are from my cell phone. 
Title: Re: a working compresion release is here
Post by: muleman on September 15, 2009, 12:14:14 PM
This past weekend I built some tooling and fixtures for the compression release modification. Then, tried out the process on my '89 head.
(http://i881.photobucket.com/albums/ac11/LJW197/DECOPM%20TEST/DSCN0676.jpg)
(http://i881.photobucket.com/albums/ac11/LJW197/DECOPM%20TEST/DSCN0677.jpg)
 
Wow larry it looks like it was molded in by the factory lol.
Title: Re: a working compresion release is here
Post by: edgar_kx3 on September 15, 2009, 12:17:37 PM
WOW!!! thats awsome work!!! i cant wait to get mine back, its on the way!! :-D
Title: Re: a working compresion release is here
Post by: Larry Wiechman on September 15, 2009, 12:22:27 PM
Beautiful work Larry.  For us guys that run a large tank IMS, Clark, it looks like we're going to need the unit on the right side of the head. Any problem with that?

No.

 
Quote
I was thinking their might be room on the left side if you were able to machine the unit to attach vertically sort of like a street L.

I played around with that concept, but it got complicated fast. I think the other side is a better option.

 
Quote
One last question what valve were you going to use?  The chain saw version or the other "Harley" version? 


The saw valve is smaller, cheaper and was manufactured with a LOT more quality control than any aftermarket HOG part.
Title: Re: a working compresion release is here
Post by: Motorrad on September 15, 2009, 06:59:32 PM
Here you can see what Im dealing with with the zip ty  tank pipe combo...

(http://img21.imageshack.us/img21/764/013en5.jpg) (http://img21.imageshack.us/i/013en5.jpg/)
(http://img195.imageshack.us/img195/8765/008ze.jpg) (http://img195.imageshack.us/i/008ze.jpg/)

here is my bike with the tank sitting on it      stewart has my motor and pipe, so I dont know where everything is in relation to the tank...

(http://img21.imageshack.us/img21/6882/dsc2986s.jpg) (http://img21.imageshack.us/i/dsc2986s.jpg/)
Title: Re: a working compresion release is here
Post by: Dutch-K5 Fan on September 16, 2009, 03:56:02 AM
I'm trying to make one with a cable and hotstarter lever!!!

Where do you have space with a zip ty tank???? My AF has a lot of space on the sides.
Would like to make it less visable, maybe I'll try it to make it on top or at the back of the head.


Dutch
Title: Re: a working compresion release is here
Post by: Motorrad on September 16, 2009, 04:21:02 AM
I think the back of the head would be more universally usable for all setups.
Title: Re: a working compresion release is here
Post by: PowerFiend on September 16, 2009, 09:38:51 AM
I'm trying to make one with a cable and hotstarter lever!!!

Dutch

I was going to suggest that myself.  :-D
Title: Re: a working compresion release is here
Post by: Dutch-K5 Fan on September 18, 2009, 07:26:29 AM
Maybe I'll buy or make this one.


http://www.racebase.co.uk/item--Decompressor-Valve-Assembly--EH_VDE5.html (http://www.racebase.co.uk/item--Decompressor-Valve-Assembly--EH_VDE5.html)



Dutchie
Title: Re: a working compresion release is here
Post by: jfabmotorsports.com on September 21, 2009, 08:58:18 AM
R&D....Rob and Duplicate...Got to love it. So easy a caveman could do it. Well the Rob part, the duplicate took a little more time. Thanks Larry, I loved the weld on bung idea.  :-D
Title: Re: a working compresion release is here
Post by: jfabmotorsports.com on September 23, 2009, 04:22:16 AM
Done deal. Works great. IMO, it is the best mod that you could do to the kx500 engine...except put it in an aluminum frame.  :evil:
Title: Re: a working compresion release is here
Post by: monster malibu on September 23, 2009, 10:46:29 AM
I'll definately take one, after having my cyl. replated and a new piston installed on my 87 KX500 it was real bear to kick. The only good thing about the hard to kick problem was there weren't to many people in my area that wanted to ride my bike because they couldn't kick it.
This mod is worth it's weight in gold easily to me.
Title: Re: a working compresion release is here
Post by: DHregdovic on September 23, 2009, 01:32:01 PM
I have mine on its way to larry right now. Can't wait for this mod to come back. Thanx again Larry!!!
Title: Re: a working compresion release is here
Post by: gortex on October 05, 2009, 08:21:14 AM
Maybe I'll buy or make this one.


http://www.racebase.co.uk/item--Decompressor-Valve-Assembly--EH_VDE5.html (http://www.racebase.co.uk/item--Decompressor-Valve-Assembly--EH_VDE5.html)



Dutchie
Just brought two of these, ones gone onto a yz490 and the other getting put on my kx500.  We putting these in the head on both bikes i'm getting the k5 done now and the 490 kicks over like a 125!!!
We got some nice hotstart levers and no one will ever know  :wink:
Title: Re: a working compresion release is here
Post by: jdb1989 on October 28, 2009, 03:40:16 AM
i have an 85 jug would it be possible for my head.
Title: Re: a working compresion release is here
Post by: Larry Wiechman on October 28, 2009, 10:23:19 AM
No problem! :-D
Title: Re: a working compresion release is here
Post by: Friar-Tuck on October 29, 2009, 06:39:08 AM
 L.W. & JFab,
 Has anyone approached you guys on doing the big CR's?   or those big MX sidecar motors?
    I believe when this gets around you're gonna be swamped...  :-D
  Tuck\o/
Title: Re: a working compresion release is here
Post by: Larry Wiechman on October 29, 2009, 11:12:03 AM
The CR's really benefit from this modification, especially if the cylinder has been bored oversize. The stock decompression grooves near the exhaust port are removed by the over bore. Now you have additional cylinder volume being squeezed into a stock volume head.
 
Larry
Title: Re: a working compresion release is here
Post by: PowerFiend on October 29, 2009, 11:58:07 AM
Anyone worked out a hotstart activated one yet?  :evil:
Title: Re: a working compresion release is here
Post by: Larry Wiechman on October 29, 2009, 12:15:09 PM
Anyone worked out a hotstart activated one yet?  :evil:

 Do you mean cable/lever operated?
 
Larry
Title: Re: a working compresion release is here
Post by: jfabmotorsports.com on October 30, 2009, 05:34:42 AM
Anyone worked out a hotstart activated one yet?  :evil:
 
 Do you mean cable/lever operated?
 
Larry

   I have been working out the details of this idea for some time. I just finished it up this morning and if the rain here ever stops I will take the K5 out and thrash it a bit.
     I think it was Dutch-K5 Fan that said he was interested in using this type of valve. The valve can be bought all over the internet and with very little head work and the little adapter that I am going to offer it can be installed on just about any head on any bike.

JFAB    


Title: Re: a working compresion release is here
Post by: Friar-Tuck on October 30, 2009, 06:17:46 AM
 I hope you guy's  make a zillion with these.
   "Find a need, Fill a need"...
  Tuck\o/
Title: Re: a working compresion release is here
Post by: Dutch-K5 Fan on October 30, 2009, 06:41:44 AM
Although it's not going fast now, I'm working on it bit by bit.
 It realy looks good Jerry!!!!!

Dutchie
Title: Re: a working compresion release is here
Post by: jfabmotorsports.com on October 30, 2009, 07:50:40 AM
Thanks Dutch, I like the one built for chain saws that I put on my KX500AF but if you are running a stock K5 with an over size fuel tank it is hard if not impossible to use especially in a hurry. I just got in from some riding and so far so good. It starts easier than the AF but the engine is bone stock as opposed to 13:1. I think that is the difference. I used the same size hole into the cylinder. Thanks again for the idea Dutch.

JFAB
Title: Re: a working compresion release is here
Post by: jfabmotorsports.com on October 30, 2009, 07:52:17 AM
Forgot to mention...I might kick it in bare feet on you tube in a bit....maybe.  :-D
Title: Re: a working compresion release is here
Post by: Danger4u2 on October 30, 2009, 04:25:26 PM
Your brave, wrap the foot peg with duct tape.
Title: Re: a working compresion release is here
Post by: kaw rider on October 30, 2009, 05:28:51 PM
Jerry
That valve looks more heavy duty compare to the other one. I think this one will work great for guys that run nasty compression.
Title: Re: a working compresion release is here
Post by: jfabmotorsports.com on October 31, 2009, 03:29:55 AM
The compression release lever that came with the generic valve kit was a small lever like the one that was used on the YZ426. I just installed a Moose lever set that had a Hot Start lever incorporated into it. It works and feels ok but I think the ASV style lever might be a little better. The little lever that came with the valve worked great but was not too sanitary.
JFAB
Title: Re: a working compresion release is here
Post by: Larry Wiechman on October 31, 2009, 10:09:36 AM
Some blurry photos of my version of the big 14mm compression release installation. This was to prove out an installation on a CR500 that had really tight space limitations.
 
(http://i881.photobucket.com/albums/ac11/LJW197/DECOPM%20TEST/DSCN0697.jpg)
 
(http://i881.photobucket.com/albums/ac11/LJW197/DECOPM%20TEST/DSCN0695.jpg)
 
Long ago, these cable operated valves were used on 2-stroke flattrackers as an engine brake. Run up to the corner, pull the lever and flick'er in. Made for nice, easy slides and a cool farting noise as the valve bled off cylinder pressure. The down side in this application  was that the motor was sucking in dirt on the intake stroke. Then someone produced a valve that had small metal reed valves covering the discharge ports. Genius! No more Filtron foam wrapped around the compression release and it even functioned better, because now there was also resistance as the piston moved down. I've searched for a supply of the one-way valves, but I think they died with the 70's.
Simple solution, don't ride around at the back of the pack doing brake slides no matter how much fun it is!
 
Larry 
Title: Re: a working compresion release is here
Post by: jfabmotorsports.com on October 31, 2009, 12:28:11 PM
     I toyed with the idea of welding a boss onto the head just as we have done with the 10mm x 1mm valves, only toward the rear of the head. I chose the stud mounted version because of less modification to the head. Also, if you decide that you do not like, no longer need it or want to sell the bike with out it, just remove the valve and put a nut back on the stud.
    I already have plans to minichureize the valve that I use in an effort to maximize mounting locations...and to cut out the middle man.

JFAB
 
Title: Re: a working compresion release is here
Post by: BullKaw on October 31, 2009, 12:39:17 PM
Long ago, these cable operated valves were used on 2-stroke flattrackers as an engine brake. Run up to the corner, pull the lever and flick'er in. Made for nice, easy slides and a cool farting noise as the valve bled off cylinder pressure. 
Larry 

I don't want to hijack this topic but this is the second or therd time that I have read this. I do not understand how releasing the pressure from the cylinder will slow the engine. Someone has compared it to a Jake Break. A Jake Break releases the preasure just befor TDC after the resistance of compressing the intake stroke has taken place. With the pressure dumped at TDC there is no pressure to rebound the piston and the engine slows.
    I know it is done and it must work but I would like to know how.
Title: Re: a working compresion release is here
Post by: Friar-Tuck on October 31, 2009, 01:34:32 PM
 BKaw,
 The application here is primarily to make the bike easier to start.
   As I see it, You are correct in that this is not an "Engine Brake", but merely an additional   application.
  The force of the piston pushing all that air out of the small passage in the valve will create some resistance.   
         If I'm not mistaken Jake Brakes "are designed" to use engine compression to aid in vehicle braking, not aid in starting.
  Hope I didn't just make this any more confusing...
 Tuck\o/
Title: Re: a working compresion release is here
Post by: Larry Wiechman on October 31, 2009, 02:23:54 PM
    Also, if you decide that you do not like, no longer need it or want to sell the bike with out it, just remove the valve and put a nut back on the stud.
   
JFAB
 

 Do you really believe someone would not like, need or want a decompression device after having used one. Can you think of a better resale feature?
 I think the future is something like this concept patented by a Husky engineer.http://patft.uspto.gov/netacgi/nph-Parser?Sect1=PTO1&Sect2=HITOFF&d=PALL&p=1&u=%2Fnetahtml%2FPTO%2Fsrchnum.htm&r=1&f=G&l=50&s1=6,253,723.PN.&OS=PN/6,253,723&RS=PN/6,253,723 (http://patft.uspto.gov/netacgi/nph-Parser?Sect1=PTO1&Sect2=HITOFF&d=PALL&p=1&u=%2Fnetahtml%2FPTO%2Fsrchnum.htm&r=1&f=G&l=50&s1=6,253,723.PN.&OS=PN/6,253,723&RS=PN/6,253,723)
 Small, automatic and simple.
 
Larry
Title: Re: a working compresion release is here
Post by: jfabmotorsports.com on October 31, 2009, 02:53:52 PM
    Also, if you decide that you do not like, no longer need it or want to sell the bike with out it, just remove the valve and put a nut back on the stud.
   
JFAB
 

 Do you really believe someone would not like, need or want a decompression device after having used one. Can you think of a better resale feature?
   
 
Larry

Larry you are right. I had not looked at it in that way. I can't imagine not having decompression valves now that I have them.

JFAB
Title: Re: a working compresion release is here
Post by: Motorrad on November 02, 2009, 03:30:55 PM
Digging the idea...  As im one of the many that can not run the chain saw setup (tank interferance). 

Few quick thoughts/questions..


Volumetrically how much extra area are we adding to the combustion chamber (how much space is in all of these adaptors, area around the stud, etc)  If you add it all up, are we getting into some serious numbers?

Hot exaust gas:  Over time, do you think there will be an issue with hot exaust gasses erroding anything?  studs, gasket serfaces around the stud.. Its amazing what things like this will do on car motors.. Will ditch things right up.

Sealing..  Just off looks, is thre now 3 serfaces you are sealing with that setup (spacer to head, adaptor to spacer, Compression release to adaptor)...  Things like that scare me a bit, being a desert racer, DNF due to  a stupid crush washer backing off etc sucks...

In another thread you said "There is a hole drilled into the chamber at an angle. The adapter is designed to capture the hole in a counter bore. " are you capturing it like say a banjo bolt?  or are you filling the entire area around the stud with combustion to then travel into the adaptor?



Anyone worked out a hotstart activated one yet?  :evil:
 
 Do you mean cable/lever operated?
 
Larry

   I have been working out the details of this idea for some time. I just finished it up this morning and if the rain here ever stops I will take the K5 out and thrash it a bit.
     I think it was Dutch-K5 Fan that said he was interested in using this type of valve. The valve can be bought all over the internet and with very little head work and the little adapter that I am going to offer it can be installed on just about any head on any bike.

JFAB     



Title: Re: a working compresion release is here
Post by: jfabmotorsports.com on November 03, 2009, 03:32:15 AM
Motorrad,
    There are only 2 sealing surfaces, valve to adapter and adapter to head. The shinny piece is a machine mark from the lathe work on the adapter. The valve has a spark plug washer between it and the adapter. My proto type uses no washer between the head and adapter. A copper washer could be used.
    I did the some math to get a rough idea of the volume created by holes and it is less that 1cc. I will do an actual cc test latter.
    The exhaust gas does share the space with the head stud and I am sure over time there will be some oil build up in that area. As far as maintenance goes, I am skeptical that it will be more than is required to keep the KIPS working. The gasses moving past the decompression valve are not hot unless you hold the valve open for a prolong period of time.
    I have a little over 20 hours of testing on mine between me and my 13 year old nephews riding the k5.
View the video; I think the plusses outweigh any maintenance issues. Even if you had to clean the carbon from it ever so often.

In the video I point out the Hot Start lever. The bike was warm but not hot. That was the first and only take with the camera. First kick!


 http://www.youtube.com/watch?v=vXDVzyiV5oA

 (http://www.youtube.com/watch?v=vXDVzyiV5oA)
Title: Re: a working compresion release is here
Post by: Friar-Tuck on November 03, 2009, 06:19:11 PM
AARGgghh... You're KIllin' me!   :-D :-D :-D
          Dang JFab That's Great!!
As an aside, I don't personally know anyone who has had problems with their comp release on their chainsaws.
  I have an OLD Craftsman (made by Echo) in the 80's and that old girl has had no prob.
     Tuck\o/
 
Title: Re: a working compresion release is here
Post by: Motorrad on November 04, 2009, 03:37:10 PM
Thanks jfab that answered a few questions I thought up really quick.  And I'm sure others had as well.
Title: Re: a working compresion release is here
Post by: Motorrad on November 05, 2009, 11:41:21 AM
How do these comp releases work jfab?

Are they lome the chain saw ones that auto kick out when the bike fires?
Or do you have to hold the leaver down to keep it engaged?'

Hard to tell from the video if you continue to hold it down with your other thumb or not...

Reason I ask. is Im looking at these as a option to the "clutch side" hot start leaver.... But if you need to continue to hold it... it would be nice to be able to use the trottle..
http://www.asvinventions.com/RotatorClamp/RCU05.php
Title: Re: a working compresion release is here
Post by: jfabmotorsports.com on November 05, 2009, 03:42:53 PM
Motorrad,
    It is hard to tell from the video. I was only trying to make the point that a shot fat guy could start the K5 without boot, from a seated position while keeping both hands on the bars.
    Yes you have to hold it while you do have to hold it while you are kicking it. That feature in itself was another reason I thought it would be a good idea to have full control over the valve. The chain saw valve that I installed on the AF will reset if the engine sneezes or hits and does not stay running for whatever reason, and we all know that happens. After having to hunt for the hot start button on my YZ426, which is on the carb right next to the choke knob, I realized that for me it would be better to have it on the bars. It my not make a lot of difference in a 2 hour hare scramble or a long distance race but I race MX and if I stall it in a berm a few second can make a lot of difference in a 6 lap race with a 2 min lap.
    I have used it with the clutch side Moose and ASV lever and the chrome one that comes in the kit.

JFAB
Title: Re: a working compresion release is here
Post by: Danger4u2 on November 06, 2009, 12:13:32 AM
I like the idea of the cable/handle bar controlled release.  With my right knee/leg problems I have to use my right hand to assist getting my foot onto the kicker.  A hot start controlled release on the left handle bar would be ideal for me.
Title: Re: a working compresion release is here
Post by: gianni2takt on December 24, 2009, 04:26:32 AM
Motorrad,
    It is hard to tell from the video. I was only trying to make the point that a shot fat guy could start the K5 without boot, from a seated position while keeping both hands on the bars.
    Yes you have to hold it while you do have to hold it while you are kicking it. That feature in itself was another reason I thought it would be a good idea to have full control over the valve. The chain saw valve that I installed on the AF will reset if the engine sneezes or hits and does not stay running for whatever reason, and we all know that happens. After having to hunt for the hot start button on my YZ426, which is on the carb right next to the choke knob, I realized that for me it would be better to have it on the bars. It my not make a lot of difference in a 2 hour hare scramble or a long distance race but I race MX and if I stall it in a berm a few second can make a lot of difference in a 6 lap race with a 2 min lap.
    I have used it with the clutch side Moose and ASV lever and the chrome one that comes in the kit.

JFAB
did you have ever gotten the remote lever adapter designed and tested for the compression release valve that i build for my bike?
Title: Re: a working compresion release is here
Post by: jfabmotorsports.com on December 24, 2009, 04:53:58 AM
gianni2takt,
    Back when the whole cable operated compression release valve was being kicked around I had thought a couple of designs through. The adapter for yours was one of them but due to the cost of manufacturing I decided to go version that had already been tested for years in other applications.
    I installed the "chain saw" valve in my personal KX500AF and it works flawlessly. The lever/cable operated one in the k5 bleeds a little more compression and works a little better in my opinion. I do like the cable idea.
   Larry is working on a his version of an adapter to remotely operate his compression release. When he gets it perfected I am sure it will be up to par with all of his work.
    
Here is a picture of the one that I came up with for the saw valve.

JFAB
Title: Re: a working compresion release is here
Post by: gianni2takt on December 24, 2009, 06:35:05 AM
gianni2takt,
    Back when the whole cable operated compression release valve was being kicked around I had thought a couple of designs through. The adapter for yours was one of them but due to the cost of manufacturing I decided to go version that had already been tested for years in other applications.
    I installed the "chain saw" valve in my personal KX500AF and it works flawlessly. The lever/cable operated one in the k5 bleeds a little more compression and works a little better in my opinion. I do like the cable idea.
   Larry is working on a his version of an adapter to remotely operate his compression release. When he gets it perfected I am sure it will be up to par with all of his work.
   
Here is a picture of the one that I came up with for the saw valve.

JFAB

looks fantastic!!!!
Title: Re: a working compresion release is here
Post by: 3Razors on December 25, 2009, 04:23:45 PM
Any problems with carbon buildup blocking the tiny hole in the head?
Title: Re: a working compresion release is here
Post by: jfabmotorsports.com on December 25, 2009, 04:30:42 PM
I have a little over 20 hrs on the '95 and it still works like it did when I installed it. I have the engine apart too offen to tell on the AF with chain saw valve.

JFAB
Title: Re: a working compresion release is here
Post by: demographic on December 27, 2009, 01:27:32 AM
What model chain saw are these decompressors off?
Title: Re: a working compresion release is here
Post by: jfabmotorsports.com on December 27, 2009, 01:45:10 AM
The ones that I use are for a Stihl 650 660...I think. I went to the saw shop and told him I needed a decompression valve for a Stihl and that is what I got. I have sence bought the cheaper blue ones off e-bay. They work just the same. I buy most of them from this guy....

http://cgi.ebay.com/Decompression-valve-fits-Husqvarna-Jonsered-Dolmar_W0QQitemZ390128244072QQcmdZViewItemQQptZLH_DefaultDomain_0?hash=item5ad5749568 (http://cgi.ebay.com/Decompression-valve-fits-Husqvarna-Jonsered-Dolmar_W0QQitemZ390128244072QQcmdZViewItemQQptZLH_DefaultDomain_0?hash=item5ad5749568)

JFAB
Title: Re: a working compresion release is here
Post by: demographic on December 27, 2009, 02:08:07 AM
The ones that I use are for a Stihl 650 660...I think. I went to the saw shop and told him I needed a decompression valve for a Stihl and that is what I got. I have sence bought the cheaper blue ones off e-bay. They work just the same. I buy most of them from this guy....

http://cgi.ebay.com/Decompression-valve-fits-Husqvarna-Jonsered-Dolmar_W0QQitemZ390128244072QQcmdZViewItemQQptZLH_DefaultDomain_0?hash=item5ad5749568 (http://cgi.ebay.com/Decompression-valve-fits-Husqvarna-Jonsered-Dolmar_W0QQitemZ390128244072QQcmdZViewItemQQptZLH_DefaultDomain_0?hash=item5ad5749568)

JFAB

Great stuff, thanks.
What thread pitch and diameter are they?

I've been looking on Google and I spotted a patent for a different type of compression release that goes in the sparkplug hole and the plug goes through it, Unfortunately I can't see the picture properly to fully understand it. I'll see if I can sign up to it.

This is the plug one...
http://www.patentstorm.us/patents/6240888/description.html (http://www.patentstorm.us/patents/6240888/description.html)
Title: Re: a working compresion release is here
Post by: demographic on December 27, 2009, 02:16:37 AM
I've just signed up so I could view that Patent properly and I'm not dead impressed with its design, you would need a long plug by the looks of it, also you would have to drill the plug threaded area.
Title: Re: a working compresion release is here
Post by: jfabmotorsports.com on December 27, 2009, 02:20:24 AM
The thread is 10mm x 1.0 on the saw valves.

From the looks of the plug type he is more than likely counter boreing the spark plug seat and then drilling a hole along side of the plug bosses threads and then routing the gas to the valve in a similar way that I have done with the remote valves. The plug is probably the same size as stock.
Title: Re: a working compresion release is here
Post by: demographic on December 27, 2009, 03:12:39 AM
The thread is 10mm x 1.0 on the saw valves.

From the looks of the plug type he is more than likely counter boreing the spark plug seat and then drilling a hole along side of the plug bosses threads and then routing the gas to the valve in a similar way that I have done with the remote valves. The plug is probably the same size as stock.

I don't suppose you have seen one with the little blue knob removed? My KMX125 from many years ago had a handlebar mounted choke that was rather handy as I remember it and I wonder if it would fit.
Title: Re: a working compresion release is here
Post by: KawPatty on December 27, 2009, 07:52:41 AM
Do you have to reset the valve if the bike fires but does not start or will it stat set?
Title: Re: a working compresion release is here
Post by: jfabmotorsports.com on December 27, 2009, 07:57:16 AM
Do you have to reset the valve if the bike fires but does not start or will it stat set?

You do have to reset the valve if the engine fires and doesn't start. That is a small inconveniance. The remotely opperated valve solves that problem.
   I am currently working on a completely automatic decompression valve. All you would have to do is kick the bike like a KX450f.

JFAB
Title: Re: a working compresion release is here
Post by: jfabmotorsports.com on December 27, 2009, 08:03:10 AM

You do have to reset the valve if the engine fires and doesn't start. That is a small inconveniance. The remotely opperated valve solves that problem.
   I am currently working on a completely automatic decompression valve. All you would have to do is kick the bike like a KX450f.

JFAB
[/quote]

I will post a little more on this later. Does anyone have any thought along these lines...good idea, bad idea, concerns?
JFAB
Title: Re: a working compresion release is here
Post by: gianni2takt on December 27, 2009, 09:56:46 AM
if you have the blue deco valve from jonsered , you dont have to reset the valve after not starting because the holes on the side are bigger . but the still valves have smaler holes but you can make them bigger and dril more holes in it like i did by my 570cc , and i do not most reset the valve after not starting and reset itselvs after starting
Title: Re: a working compresion release is here
Post by: demographic on December 27, 2009, 10:16:11 PM
if you have the blue deco valve from jonsered , you dont have to reset the valve after not starting because the holes on the side are bigger . but the still valves have smaler holes but you can make them bigger and dril more holes in it like i did by my 570cc , and i do not most reset the valve after not starting and reset itselvs after starting

Does the Jonsered (and I assume that Husqvarna will be the same cos J Reds have been bought out by Husky and often pretty much the same saw with a different colour) valve have the same thread diameter and pitch as the Stihl one?
Title: Re: a working compresion release is here
Post by: jfabmotorsports.com on December 28, 2009, 01:34:06 AM
Does the Jonsered (and I assume that Husqvarna will be the same cos J Reds have been bought out by Husky and often pretty much the same saw with a different colour) valve have the same thread diameter and pitch as the Stihl one?

They do have the same threads. They are almost identical. The Stihl does have smaller holes than the others. I have used both and did not notice a big difference in kicking effort. I went back to the Stihl valve with the black knob on my bike. I didn't like the blue knob.
Title: Re: a working compresion release is here
Post by: demographic on December 28, 2009, 06:00:00 AM
Does the Jonsered (and I assume that Husqvarna will be the same cos J Reds have been bought out by Husky and often pretty much the same saw with a different colour) valve have the same thread diameter and pitch as the Stihl one?

They do have she same threads. They are almost identical. The Stihl does have smaller holes than the others. I have used both and did not notice a big difference in kicking effort. I went back to the Stihl valve with the black knob on my bike. I didn't like the blue knob.

Fair comment as the black one does look more like it was put there by Kawasaki, there's a local tool dealer that sells J reds, Huskies and Stihls so I should have a fair choice if I go for it.

I'm not dead keen on the idea of drilling a hole in my cylinder head though.
Title: Re: a working compresion release is here
Post by: jfabmotorsports.com on December 28, 2009, 09:38:35 AM
Fair comment as the black one does look more like it was put there by Kawasaki, there's a local tool dealer that sells J reds, Huskies and Stihls so I should have a fair choice if I go for it.
I'm not dead keen on the idea of drilling a hole in my cylinder head though.

I was a little sceptical at first. A chain saw gets used a lot more hours than KX500 and they are still useing them. That was how I justified it in the begenning. Now that I have one there is no going back.

JFAB
Title: Re: a working compresion release is here
Post by: demographic on December 28, 2009, 07:58:16 PM
Fair comment as the black one does look more like it was put there by Kawasaki, there's a local tool dealer that sells J reds, Huskies and Stihls so I should have a fair choice if I go for it.
I'm not dead keen on the idea of drilling a hole in my cylinder head though.

I was a little sceptical at first. A chain saw gets used a lot more hours than KX500 and they are still using them. That was how I justified it in the beginning. Now that I have one there is no going back.

JFAB

Sorry, I didn't make my post very clear, I'm not bothered about someone else who knows exactly where to drill the hole doing it, I just don't know exactly where to do it myself and by the time I would have sent the head over to the US and back plus the cost of the work, its more money that I currently have spare.

I really like the idea and considering I ride mine on the road I don't want to be wearing massive clumpy MX boots when I do. Having a decomp valve would make a huge difference to it.

Just have to save my pennies up.
Title: Re: a working compresion release is here
Post by: gianni2takt on December 29, 2009, 06:48:31 AM
I never thought I could be sold on the comp release. Who ever it was that came up with that is a real thinker. I like it and I would have one on my bike for sure.
that real thinker was me
Title: Re: a working compresion release is here
Post by: gianni2takt on December 29, 2009, 06:53:53 AM
Fair comment as the black one does look more like it was put there by Kawasaki, there's a local tool dealer that sells J reds, Huskies and Stihls so I should have a fair choice if I go for it.
I'm not dead keen on the idea of drilling a hole in my cylinder head though.

I was a little sceptical at first. A chain saw gets used a lot more hours than KX500 and they are still using them. That was how I justified it in the beginning. Now that I have one there is no going back.

JFAB

Sorry, I didn't make my post very clear, I'm not bothered about someone else who knows exactly where to drill the hole doing it, I just don't know exactly where to do it myself and by the time I would have sent the head over to the US and back plus the cost of the work, its more money that I currently have spare.

I really like the idea and considering I ride mine on the road I don't want to be wearing massive clumpy MX boots when I do. Having a decomp valve would make a huge difference to it.

Just have to save my pennies up.
http://www.kxriders.com/forums/index.php/topic,5255.0.html  in this topic on page 5 you can see how you can make it yourself :wink:
Title: Re: a working compresion release is here
Post by: demographic on December 29, 2009, 08:11:07 AM
http://www.kxriders.com/forums/index.php/topic,5255.0.html  in this topic on page 5 you can see how you can make it yourself :wink:

I haven't been on this forum for a while and missed out on that thread, thanks very much for the link.

What a great idea.
Title: Re: a working compresion release is here
Post by: jfabmotorsports.com on December 29, 2009, 12:50:45 PM
demo,  I did misunderstand. Sorry for that. The infor that you were linked to will get you there yourself.
JFAB
Title: Re: a working compresion release is here
Post by: demographic on December 29, 2009, 07:55:38 PM
demo,  I did misunderstand. Sorry for that. The infor that you were linked to will get you there yourself.
JFAB

No worries at all, we are all here to help each other as far as I see it. This forum has changed a huge amount in the last few years and is now more of a source of technical information than ever.
Title: Re: a working compresion release is here
Post by: stewart on April 15, 2010, 04:08:39 AM
here are some pictures of the high quality work from larry wiechman ,,very nice job on these heads modded for the release   thanks larry great work
Title: Re: a working compresion release is here
Post by: Friar-Tuck on April 15, 2010, 04:58:59 AM
 :cry:....  8-)
    Thou Shall not Covet... Thou Shalt not Covet....

 Tuck\o/
   
Title: Re: a working compresion release is here
Post by: Danger4u2 on April 15, 2010, 05:08:14 AM
Is that one from my bike???
Title: Re: a working compresion release is here
Post by: cbmoor on April 15, 2010, 05:22:41 AM
Or is the one for me  :wink:
Title: Re: a working compresion release is here
Post by: Danger4u2 on April 15, 2010, 05:54:58 AM
Or is the one for me  :wink:
Really, my motor is at his shop.
Title: Re: a working compresion release is here
Post by: cbmoor on April 15, 2010, 06:02:24 AM
Mine is in my bike I just ordered a head from Stewart and I cant wait till it arrives
Title: Re: a working compresion release is here
Post by: stewart on April 15, 2010, 06:04:49 AM
Is that one from my bike???
yes  i got 5 of them back one is yours they look fantastic
Title: Re: a working compresion release is here
Post by: stewart on April 15, 2010, 06:06:46 AM
Mine is in my bike I just ordered a head from Stewart and I cant wait till it arrives
yes one of these is for your bike as well ,,today i was checking the bleeder bolt holes and plug threads on every head then lapping the decks then mesuring the ccs and thickness of each head