KX Riders
Maintenance & Technical => KX500 Original => Topic started by: tcoop474 on November 06, 2011, 02:57:17 AM
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I'm having a pretty hard time getting my k5 to crank. It'll backfire everynow and then I got it to crank once so far. I'm 123lbs so not much ass behind the kicks but I get it to turn over a good bit just won't fire. I checked the plug it looks okay but its a bp7es ain't it supposed to be a br8eix?
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Hey Coop,
There is a long thread on how to start, so there are many variations. One common piece (I think) inthat puzzle is getting the piston to or in your case just past TDC. By doing so you can at least get everything moving and get at least one full revolution of the engine.
Slowly move the kicker until you feel the compression get to the highest point you can feel.
This may take a few "Cycles" of the kicker to see what I'm talking about. Once you feel you have gotten to or just past the point of most compression stop. Bring your foot back up to the top of the stroke on the kicker, use your left leg to jump up and come down on your right leg while kicking down.
(There is a video of a chap username Rob129 from CR500riders.com that made a video explaining this whole sequence, I'll look for it when we get home from church.)
The other part of the equasion (I use) is always starting and warming up the bike while still tied down in the truck. That way you don't have to worry about balancing the bike while jumping up and then down on the kick. Once my bike is warmed up it is 98% one kick the rest of the day.
The only experience I had with kicking back was when I was messing with the timing. Once I set the timimng back to the original Center timing mark I didn't have any problems.
The breix 7 is a hotter burning plug than the 8 or 9 That is the heat range on an NGK
I use a 7 as I mainly plunk around the mountains on single track and rarely "open her up"
A guy who rides the dunes and desert would be well served using a 9 as the bike spends more time between 3/4 and W.O.T. The plug will dissapate heat built up by long periods of large throttle.
do a search on sparkplugs and find more than you will ever need to know :-D
Got to go, try the just after tdc on your starting and I would suggest a 8 series heat range (NGK) for starters.
Tuck\o/
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Thank you tuck. I have already read that read way before I got a kickstart lever for the k5. I always do put it a tdc before kicking. Its my fault I didn't ask the question the right way I don't guess.
What I'm asking is what are some reason as to why it won't crank or why its so hard. I can tell a huge difference in kicking it Friday to yesterday.
Its not wanting to crank. Friday it hadn't been ran in bout 3 months and I could crank it in about 5the kicks. Yesterday however I kicked it for hours literally hours 3 to be exact and it would not ever crank
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If your jetting is off it would make it harder to start, 3 months ago was summer jetting. Did you turn off your fuel when you put it away, could be flooded pull your plug & see if it is wet. Basic's air, fuel, spark. Air doesnt really go bad as long as you clean your filter, so fuel & spark are generally where to look. I'd lean to flodded where you say its harder to kick. Hope it helps
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I kicked it for hours literally hours 3 to be exact and it would not ever crank
:-o
Friday it hadn't been ran in bout 3 months and I could crank it in about 5the kicks.
Oh Dear, if she won't start in 5 or so minutes I would def. start looking for other problems.
Just so I'm clear on the recent problem, the bike hadn't been run for three months or so, last Fri. it took about 5 or so kicks to get it started, it ran, but it ran poorly.
Saturday you could not get the bike to even start.
Yikes...
'81CR makes some excellent points.
Fuel will leak in the engine (over time) and as you rotate the crankshaft the raw fuel will
fill or leak into the crankcase and instead of compressing the air/fuel mixture, there is so much raw fuel in the cyl. it won't compress and actually lock-up the engine, or be very difficult to spin over the engine.
I don't think this is the case as you are able to rotate the engine with the kick start lever.
'81 also brings up the jetting issue. if the bike was running well in the warm weather, and now it's cooled down considerably, the backfire you are experiencing may well be a lean condition. It may be hard to start even with the choke on.
The cooler dense air will require richer jetting.
If the bike was just too lean I think it would probably start, but would not run very well. Popping and back/fireing etc.
You may just have a look under the flywheel cover and see if the flywheel key has been sheared.
This would give you the impression the bike wants to start, it feels like one more kick will light off the engine but it just won't start.
So...
Have a look at the key on the flywheel, if that checks out I would pull the plug and look for ignition and fuel.
You will probably need a hand kicking the bike or holding the plug to ground to check for fire while cranking.
Is the plug wet or dry, when you pull the plug initially is it wet or dry, and what color is it. Black and sooty or grey/white, etc.
If both those check out I would pull the carb for a good cleaning
(and write down what jets are in there for reference.)
While the carb is off have a look and check the reeds for cracks chips or the like.
I know it will take some time to pull the carb and check the reeds. but I don't know how else you can know for sure they are good to go.
Please hang in there with us and we should be able to get this figured out.!
Tuck\o/
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I had a hard time getting my kx5 started when i first got it. I put mine in 1st and rock it back and forth for about 30 seconds, then put it back in neutral, make sure the choke is on, make sure it is at top dead center and then kick it like you mean it. sometimes mine will back fire a couple of times before it starts. im also 280 lbs so its a little easier to get it to crank. try standing on something or leaning the bike against something to help you get more leverage.
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I'm having a pretty hard time getting my k5 to crank. It'll backfire everynow and then I got it to crank once so far. I'm 123lbs so not much ass behind the kicks but I get it to turn over a good bit just won't fire. I checked the plug it looks okay but its a bp7es ain't it supposed to be a br8eix?
If the bike is backfiring it's trying to do something. Try a fresh plug (I prefer B8EG's) add some fresh fuel. And try again. If you keep hearing a backfire you possibly have a sheared flywheel key. The other issue is my famous "do a compression test" speech. 75% of the "my bike wont start or bogs" issues stem from a blown or weak top end.
I lean my 500 over hard to the left until i see a bit of fuel spill out the carb overflow, then I kick 2 or 3 times and it lites off every time.... starts one or two kicks hot as well. I have approx 170 psi for compression (I have Kawis optional thin head gasket). Most stock 500's put out about 155 psi in good condition.
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Thanks guys. Someone mentioned jetting the old plug I pulled out was a paper bag brown color. Some one mentioned spark plug b8eg did you mean br8eg? If so I put one in yesterday with no luck. As far as the woodruff key this was one of my first thoughts but haven't checked it yet. And no Friday it didn't run poorly it ran great as usual. The backfiring is while trying to crank it not while running thanks
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Let me add my 2 cents to the discussion. It sounds like once the bike starts it runs well. I would check the Carb Float Height. A Float Height that is too low would cause hard starting and an occasional backfire as the vacuum signal produced during the start cycle (kicking the bike over) is different than when the bike is running. It takes a good boot to get things spinning to create the required vacuum to pull the fuel up from the fuel bowl into the various Carb passages. Keihin PWK Carb Float Height 16mm. Again my 2 cents and something I would check.
S
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I think its my Carb to cylinder intake boot. Just found a crack in it
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I think its my Carb to cylinder intake boot. Just found a crack in it
Uh oh..... I hope the bike has not been ridden WO with that cracked intake boot.... anyways good eye...
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is the crack flowing air or just on the surface? 86 air boots are like rocking horse sh&t, although someone said they can be repaired with a liquid rubber type approach.I would check the woodruff key asap, as they will backfire when this is busted.using fine grinding paste to lap the f wheel to crank taper makes this a thing of the past.take care to keep it away from crankseals and clean excess off after doing it.K.
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When I cant get my 5 to start, I just get CBX to kick it (in his Flip-Flops). Fires every time, huh DoldGuy. :-D
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When I cant get my 5 to start, I just get CBX to kick it (in his Flip-Flops). Fires every time, huh DoldGuy. :-D
:-D
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I have no idea how long the intake boot has been in this condition but I'm sure its not like a just happens thing. And I have been pulling it off this is the first I've had a kick lever so Idk if this is a new problem or not.
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Thank You guys for jumping in, I'd totally missed checking the air boot, float level and all.
Excellent points on the signal strength and float level Serafin.
Plugs:
The NGK plugs R is resistor so Br8 is resistor b8e is non resistor
More than you ever want to know about plugs from the manufacturer
NGK USA
http://www.ngksparkplugs.com/tech_support/didyouknow.asp?mode=nml
Sparkplug 411
http://www.ngk.com/sparkplug411.asp
And my Good Brutha K-Wack,
If you pull the flywheel, use some valve lapping compound to lap the flywheel to the crank.
It Only takes a few moments.
Make sure to clean the crank with solvent or parts cleaner to remove all the paste. Simply apply the compound to the snout and turn the flywheel a minute or two by hand back and forth and look for any high spots on the crank.
Thanks again guys and sounds like you are at least making progress Coop, finding the boot with a possible crack is possibly catastrophic. The bag colored plug insulator would lead you to believe alls well, but that may not be a tell all.
If I'm not mistaken the plug chop test and mixture ring is actually read at the bottom of the insulator.
Not easy to see without a lighted magnifier or cutting the plug open. Reading the electrode and strap is a science all its own.
I'll look for an article
Tuck\o/
Gordon Jennings :-D
http://www.strappe.com/plugs.html
O.K. last one...promise Reading timing etc The stuff I'm not sure about......
http://www.angelfire.com/fl4/pontiacdude428/Readplugs.html
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When I cant get my 5 to start, I just get CBX to kick it (in his Flip-Flops). Fires every time, huh DoldGuy. :-D
Spray some PAM cooking spray on the bottom of those flip flops for some better kick lever grip... :-D
You guys crack me up...LOL
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So I don't need to be using the br8eg plug I need a b8eg?
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US specs call for the non resistor plug, Canadian specs call for the resistor plug. No other parts differences. Can't see it making that big of a difference other than a little emitted efi noise suppression on the resistor plug.
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coop, do you mean youve been bumping it as you didnt have a kicker?
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when bumping, the engine tends to turn over faster than by boot leather, which, due to the higher signal strength means it will generally start with an air leak.(boot, main seals, cases etc). as the signal strength is lower when kicked, the air leak will make sufficient difference that she won't go by kicking.had this prob myself before i got into strokers on an addicted level.the cracked boot if admitting unmetered air would be enough to cause 'no ride today' frustration. however, I would advise, after sorting the boot issue, to do a pressure and vacuum test to make sure its not leaking anywhere else.as I mentioned 86 air boots are rare in good nick, and due to the mk1 rear suspenders, the 86 boot is a straight shot, and the 87 on arent, due to differing shock location as opposed to the mk2(87 on) uni trak system.if the liquid rubber suggestion is no good, I would consider asking jfab or larry to do you a new one in ally.hth, K.
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Either will work, the R is for resistor, interference of peoples tv, radios.
I didn't think much of it till I over herd someone say that a non resister plug can cause interference with the ignition system of your own bike. So now I use a R plug just in case.
Bob W
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that explains why the mini moto fooks the telly up and the 5 doesn't then.everydays a school day! K.
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thinking about it, you could use a later boot but it would mean junking the airbox and running a K&N or simillar, which I wouldnt advise if you use it for anything other than road/sm use.you want the airbox for dirt.K.
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When I cant get my 5 to start, I just get CBX to kick it (in his Flip-Flops). Fires every time, huh DoldGuy. :-D
Spray some PAM cooking spray on the bottom of those flip flops for some better kick lever grip... :-D
You guys crack me up...LOL
Polar,
Roost was not kidding, his race was coming up & I saw him kicking with all of his 130 lbs & he could not get it to light. I too was wearing flip flops & knew there was NO WAY I could start it, then CBX comes to the rescue in his Flippers!
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Yes when I got the bike there was no kicker on it guy said he always pulled it off. I pulled it off till I got a kicker. Friday night was my first attempt with the kicker and it cranked and I rode it for a while then sat and sun I kicked it all day with no success
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if you kick it and it wont run, but will when you bump it, almost deffo the air leak causing it.but you dont want to run it like that anyway, just do more damage.cant remember who suggested this liquid rubber stuff, but it was in reference to a leaking air boot, and if I remember correctly it fixed the issue.hth, K.
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hows your compression? low cyl comp also has the same effect due to the differing cranking speeds.K.
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Here's the verdict. I tried cranking it again last night with no luck so I decided it was time to actually do more then just look at the bike waiting on it to tell me what was wrong with itself. Rand compression test came back with 90 psi. I toilet the head off and it was pretty gummed up. Went to take exhaust off noticed gas running from around the exhaust and down the front of the motor. Took the cylinder off no scratches or scars on the sleeve but rings seized to piston. Motor is pretty gummed up so I'm going to clean it up real good new gaskets rings ect. The piston is a wiseco 86mm I think? What ever stock mm is ran the serial number its made for 88-up k5s mine is an 86 I'm sure its not a problem but there is a lot of play from side to side. Like from inside of piston it has a gap on each side to the crank. Can slide it a good bit from left to right.
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O yea and I've decided to go ahead and take it to bare frame and go ahead and build it completely as originally planned when I got it.
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Here's the verdict. I tried cranking it again last night with no luck so I decided it was time to actually do more then just look at the bike waiting on it to tell me what was wrong with itself. Rand compression test came back with 90 psi. I toilet the head off and it was pretty gummed up. Went to take exhaust off noticed gas running from around the exhaust and down the front of the motor. Took the cylinder off no scratches or scars on the sleeve but rings seized to piston. Motor is pretty gummed up so I'm going to clean it up real good new gaskets rings ect. The piston is a wiseco 86mm I think? What ever stock mm is ran the serial number its made for 88-up k5s mine is an 86 I'm sure its not a problem but there is a lot of play from side to side. Like from inside of piston it has a gap on each side to the crank. Can slide it a good bit from left to right.
Hate to tell ya' but I told ya so..... sounds like you are one of the luckier ones... you might get off with just a new top end.
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I fig it was by how easy it was to kick but just was hoping it wasn't wanted to ride a little longer lol
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Well,
At least you will Know what you have Coop. There's a thread that I think D'old Guy started thats asks the best mod for the K-5...there are more than just a few blokes who will agree.
A good refreshing will do wonders for the old girl! I think you are gonna be in for a pleasant surprise once you get her lit off after the re-build.
I think you are doing the right thing, and with any luck she'll be ready by spring!
Tuck\o/
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Hopefully but its not my only bike. I'm still building my 89 trx 250r as well but they should both be done soon. Still trying to fig out what all I wanna do to the k5 ill finish taking it to bare frame today probably
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do the bottom end as well.if you don't you'll wish you had.K.
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turn fuel on, lean bike over until fuel runs out of carb overflow line. crank bike over 2 easy kicks then kick the s**t out of it why? when you 2 easy kick it, your pushing fums of gas into the cylinder. It will start. Maybe drop slow jet 1 size
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turn fuel on, lean bike over until fuel runs out of carb overflow line. crank bike over 2 easy kicks then kick the s**t out of it why? when you 2 easy kick it, your pushing fums of gas into the cylinder. It will start. Maybe drop slow jet 1 size
X2 on the TIP method, had an old guy that did cold start hare scrambles show me & it really helps. Just down on its side & right back up
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Let me see if the float bowl isnt stuck wide open, how does fuel get into the chamber, in other words if floats close when carb is full, no gas goes anywhere
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1- compression release 2- soak your Carb over night make sure its clean 3- new NGK#8 Iridum plug 4-Blue-TT-111 octange gas 5-Saber pre mix 2 cycle oil. My mix is 70:1 my 500 starts first kick ever time.My plug the color is good it dosent slobber like before and i dont have all the smoke.But i do miss the castrol smell.Ran this way the last 7 months and everthing good.
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When you shut off the fuel to park the bike & let it sit for a few days the fuel likes to evaporate from the bowl so the carb is dry. I you just turn back on the fuel to restart the bike it kind of pressure locks for a bit & takes some violent /more kicks/ shaking to get the fuel down in the bowl. Where if you tip it to the side it relieves the prussure & will take less kicks to start cause the bowl is already primed.
This is if I understand what you were questioning awak100
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Wow talk about bringing a thread back from the dead lol. Since this thread was last updated ive rebuilt the top end and did a bunch of other cleaning up on it. But still the same thing.
I CANNOT CRANK THIS BEAST. I simply dont have the ass i had a crf450r i could crank 1-2 kicks after sitting for a month but this thing hell no i can put both feet on the kicker and jump on it with no success.
I do know for a fact its just me cause i have some friends that way more then i do that can get it to fire fairly easy once the stop being scared.
What can i say im all of 5"9 120lbs aint much i can do. Ill be taking the head off tonight to send to jfab for compression release.
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5'9" and 120? You must look like a male version of olive oyl, lol
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Lmao nah just skinny. Im 5"7 not 9 typo just dont gain weight
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Well be glad. Right now i'm 5'10" about 210 and its hard to keep the weight off. If i eat like i did 5 years ago i gain like crazy. I'm just about 28 years old, forgot to mention that.
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Lol yea its all gonna catch up to me one day. Im 21 so still got a d**n good metabolism lol. I work construction so that helps keep the weight off also.
I got my dream job so to speak the other day. Be working on quads and bikes everyday and get certified so itll be sweet
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i'm 5'10" and 160 lbs, unfortunately at 46 years old, 45 lbs of that 160 resides in my gut... :oops:
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Id say at 46 to be 160 thats pretty good shape. But then again i live in alabama one of the fattest states lmao so what do i know.
In high school i wrestled and played football i tryed my hardest to get big muscle wise. I was drinking weight gainers, whey protein and eating non stop taking in well over 2k calories and i was losing wieght. I just gave up
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Drian the old gas out. mix aims saber 70%1 8NGK irumin plug while you got the carb off checking reeds soak the carb over nite clean filter change tranny.I would kick my 500 till it almost broke my heart and body and it wouldnt start. I read ever thing i could find here on KXR and put it to use.Now in tennis shoes fires first kick arent i the lucky dog
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Ive seen a lot ppl saying mix 70:1? I mix 40:1 with benol. Should i be at 70:1? Prev owner ran 40:1 and thats what i run in my quads also