KX Riders

Maintenance & Technical => KX500 Original => Topic started by: 99tjrockcrawler on May 16, 2005, 02:37:03 PM

Title: Porting and Polishing
Post by: 99tjrockcrawler on May 16, 2005, 02:37:03 PM
What do you guys know about porting and polishing?  How much more power does it really give?  Any recommendations on where to get it done on the west coast.  I live in vegas.  I am really getting tired of those darn 450's beating me.  I run mostly in the sand and I know my bike is faster but with my weight the 450's take me a just a hair.  I want to add more power but not really tear intot the motor because I want it to stay reliable and it seems like the more mods you do the more it breaks.

Thanks for any help!!

MIke
Title: Porting and Polishing
Post by: Arigato on May 17, 2005, 04:04:04 AM
It definately makes a difference on the K5.  Send it to Eric Gorr and have him to the "mo betta everywhere" port job to the cylinderl.  There are a lot of casting flaws in the stock cylinder.  I live in 'Vegas too.  We should hook up and ride.
Title: Porting and Polishing
Post by: reknelb on May 17, 2005, 05:28:17 AM
You may want to check on turn around time before sending to Gore. I've seen alot of complaints online about turn around. I've also seen some of his responses to unhappy customers on a certain website. Not sure I would send anything to him myself, although I hear his work is really good. (and cheap)
Title: Porting and Polishing
Post by: gowen on May 17, 2005, 05:56:07 AM
I'd be for the porting from Gorr too, but I am a little pro-Eric, as he has hooked up most of my dirtbikes with no trouble and pretty fast too. Just be patient, he is one person handling hundreds of jobs. The outcome is awesome. Yes, dirtrider has had complaints, but I've never had any and have had 10 motors sent to him, 5 being ones I owned.. (including my KX, it is in for the second time (520 :-) ) due to my own stupidity)
Title: Porting and Polishing
Post by: gwcrim on May 17, 2005, 07:52:09 AM
I had Gorr do my top end.  I even went with an over sized bore.  Isn't bigger always better?  I've been 100% satisfied with Eric Gorr's service.
Title: Re: Porting and Polishing
Post by: delusionised on May 17, 2005, 05:46:54 PM
Quote from: 99tjrockcrawler
What do you guys know about porting and polishing?  How much more power does it really give?  Any recommendations on where to get it done on the west coast.  I live in vegas.  I am really getting tired of those darn 450's beating me.  I run mostly in the sand and I know my bike is faster but with my weight the 450's take me a just a hair.  I want to add more power but not really tear intot the motor because I want it to stay reliable and it seems like the more mods you do the more it breaks.

Thanks for any help!!

MIke


How much do you weigh? I weigh 248 and i race up against an 02 crf450 all the time and my buddy is around 200 lbs, when I was bone stock and so was he we pulled dead even on a road drag race, I then put a fatty on and vforce reed cage, I stayed with stock jetting and now I pull away, I let him go ahead and then I caught him and past him and he was nevergoing to see me again. I think 450's will run with ya until ya hit 5th and are on the pipe then they start falling behind, Dont ask me how cause we have mega torqe advantage and about 5-8 more peak horsepower STOCK! . Are you piped or valved? any way I wish you luck on smokn them bastads.
Title: Porting and Polishing
Post by: mikesmith on May 17, 2005, 07:14:43 PM
I cleaned up my own porting and suggest you talk to Doordie if you want to do your own,otherwiase try Pro-Circuit.
Title: Porting and Polishing
Post by: Brett on May 18, 2005, 01:00:40 AM
Just one thing on the porting side of things (ignore polishing as is just for dickywackers), i have seen a few dividers between main and auxillary transfer ports being knife edged which i have allways rounded rather than sharpened as flow is travelling up the transfers and as we all know the shape of a teardrop sureley this is the best approach.  I just actually cleaned up my ports last night and found the worst spot (best spot to fix) is the passage between where the reed block bolts and the main transfer port, there was tonns of casting flash here that required removal. The only other spot i thought was worth time on was the three passages between the crankcases and cylinder, these are an abrupt entry into the crankcase and also required rounding.  I was very surprised by the match quality of the main and auxillary transfer ports to the crankcase.  I am still yet to play with the exhaust ports but having a quick look reckon that there is possibly good cause to soften exit of auxillary exhaust passages(where powervalve drum seals off) as is a very sharp exit.  When i get down to a bearing store to buy my replacement pins for my powervalve i will get to have another play with the windy. :D
Title: Porting and Polishing
Post by: 99tjrockcrawler on May 18, 2005, 03:10:03 PM
Thanks for all the info.  Who is Eric Gorr and where is he?  Does he have a website?  I tried a pro circuit pipe but it did not seem to help the top end just the low to mid.  I have a Reed valve from 1Dir Racing which did improve eberything.  I weigh about 250-255.  And I always lose to the new crf450r's.  Not by much but I can't pass him if he gets the holshoot.  This is always in sand topping out in 3rd if I hit 4th it bogs.  10 paddle skat trak.  How much about would a porting and polishing job cost?  Not worried about time as it is summer here and I don't do much riding in the summer.

Thanks again.

p.s.   Arigato...where do you ride most of the time?
Title: Porting and Polishing
Post by: Arigato on May 18, 2005, 03:15:08 PM
In the summer, we go to Coral Pink (June 17 is the first one) and Little Sahara.  Both are in Utah.  I also try to hit Mesquite and Glen Helen for a moto fix.  Come to Coral in June.  There will be some cool 500's:  2 custom KX's, 2 CR500AF's and 2 steel-framed CR500's.
Title: Porting and Polishing
Post by: mikesmith on May 18, 2005, 09:48:24 PM
You probally have the Pro Circuit MX pipe,there desert pipe will give you more mid/top end.
Title: Porting and Polishing
Post by: doordie on May 19, 2005, 08:43:06 AM
Look in "favourite mods" and "sticky part of rebuilding a top-end" by John! :wink:

//doordie
Title: Porting and Polishing
Post by: 99tjrockcrawler on May 19, 2005, 05:50:09 PM
Quote from: Arigato
In the summer, we go to Coral Pink (June 17 is the first one) and Little Sahara.  Both are in Utah.  I also try to hit Mesquite and Glen Helen for a moto fix.  Come to Coral in June.  There will be some cool 500's:  2 custom KX's, 2 CR500AF's and 2 steel-framed CR500's.


We are going to coral pink next weekend (memorial weekend) for the first time.  Do you have to rejet for that area?  Where is little Sahara?
Title: Porting and Polishing
Post by: Arigato on May 20, 2005, 01:29:54 AM
You may have to lean her down one jet, but the sand is really soft so go in small increments.  Make sure you have buggy whips for all of the toys.  Little Sahara is about 2-3 hours north of Cedar City.  Both places are awesome....We stay away from both on the big weekends...Too many yo-yo's on the dunes with beer.  We wait until after the last ride to get hammered.
Title: Porting and Polishing
Post by: Timbowe on May 20, 2005, 09:07:34 AM
Looking choice there bro! Digin the XGx.
Title: Porting and Polishing
Post by: 99tjrockcrawler on May 20, 2005, 12:32:36 PM
Your bike looks great.  Where did you get the black plastic?  I was going to order graphics from the same place you got yours just a little different one.



Quote from: Arigato
You may have to lean her down one jet, but the sand is really soft so go in small increments.  Make sure you have buggy whips for all of the toys.  Little Sahara is about 2-3 hours north of Cedar City.  Both places are awesome....We stay away from both on the big weekends...Too many yo-yo's on the dunes with beer.  We wait until after the last ride to get hammered.
Title: Porting and Polishing
Post by: Arigato on May 21, 2005, 07:47:32 AM
MXsouth.com for the plastic.
Title: Porting and Polishing
Post by: GDubb on May 22, 2005, 06:20:58 AM
Hey 99tjrockcrawler... I ride dunes all the time on my 5, and one thing nobody touched on is the fact that you are bogging in 4th... my bike never boggs, even in 5th, unless I miss-shift and hit a gear too early. I think there may be something wrong with your bike like jetting,  lack of compression or something. I've never had the opportunity to drag race a new 4stroke (they seem to all go the other direction when I come around on the green beast) but I do know that this bike which is all stock with FMF pipe and silencer and a sand snake 10-cup paddle, has more nuts than I know what to do with and never boggs unless its because of rider error.  Just wanted to point that out since nobody else touched on it.
Title: Porting and Polishing
Post by: BrianSM on May 23, 2005, 05:37:29 PM
I can say for track....I outpull SMR525's with alot of engine work, I also outpull the CRF's with engine work as well same with YZF's.....the bottom end If not geared right they get a jump on me (If I'm geared right and on the pipe noway)...those bikes are fast but the greeny is faster
I'm with GDubb, your scoot is not running to its potential......
Title: Porting and Polishing
Post by: 99tjrockcrawler on May 26, 2005, 12:28:58 AM
Quote from: GDubb
Hey 99tjrockcrawler... I ride dunes all the time on my 5, and one thing nobody touched on is the fact that you are bogging in 4th... my bike never boggs, even in 5th, unless I miss-shift and hit a gear too early. I think there may be something wrong with your bike like jetting,  lack of compression or something. I've never had the opportunity to drag race a new 4stroke (they seem to all go the other direction when I come around on the green beast) but I do know that this bike which is all stock with FMF pipe and silencer and a sand snake 10-cup paddle, has more nuts than I know what to do with and never boggs unless its because of rider error.  Just wanted to point that out since nobody else touched on it.


When I say it bogs, It is only when racing up steep hills and I guess bogs is a bad word to use.  When I shift from 3rd to 4th it just stops pulling and seems like I can't get it in the powerband as the hill is too steep.  On flat ground it runs fine 3rd, 4th, 5th.  Looking to get more power so when I hit 4th it is still pulling like 3rd.  I also have checked jetting and it is right on and the compression is still good.  

If that is all you have done to your bike than I would say you would probably lose to the new 450's racing uphill as I have never seen a 5 beat one yet when the rider on the 450 knows what he is doing.
Title: Porting and Polishing
Post by: Arigato on May 26, 2005, 02:14:40 AM
I own both, and have ridden and raced against both on the hill (Dumont, Sand Mountain, Coral Pink).  Rider weight and skill being equal, a KX500 or even a CR500 properly jetted will smoke a 450 four stroke.  Call me 592-9304 and let's get yours straightened out.
Title: Porting and Polishing
Post by: 99tjrockcrawler on May 26, 2005, 04:56:39 PM
Quote from: Arigato
I own both, and have ridden and raced against both on the hill (Dumont, Sand Mountain, Coral Pink).  Rider weight and skill being equal, a KX500 or even a CR500 properly jetted will smoke a 450 four stroke.  Call me 592-9304 and let's get yours straightened out.


Hey thanks..I will do that.  We are going to coral pink this weekend and this will be our last trip out to the dunes for the summer as it is now jetski season.  I plan on working on the bike over summer to get it ready for next season...
Title: Re: Porting and Polishing
Post by: Rhyno on November 04, 2012, 05:59:08 AM
I own both, and have ridden and raced against both on the hill (Dumont, Sand Mountain, Coral Pink).  Rider weight and skill being equal, a KX500 or even a CR500 properly jetted will smoke a 450 four stroke.  Call me 592-9304 and let's get yours straightened out.

I know that this is an old thread.

Whatever became of this?  What were you able to figure out and change?

Thanks.....
Title: Re: Porting and Polishing
Post by: crazyolbastard on November 07, 2012, 01:38:10 PM
Look in "favourite mods" and "sticky part of rebuilding a top-end" by John! :wink:

//doordie

how about a link?
I can`t find it. :roll: