01 426 Stopped running and won't start again!!


38 replies to this topic
  • beasleys

Posted February 23, 2006 - 05:32 PM

#1

I was riding my 426 at the track this afternoon. Something major happened. :bonk:
I was going through a small whop section and the bike stalled. It died kind of weird while I was in 3rd gear or so and one the gas and it just died. I stopped and after a few of the ritual kicks it fired up. :thumbsup:
Ran for another 30 minutes or so just fine. Was riding in 4th and on the gas and it did the exact same thing.
It almost threw me over the bars it happened so fast. It was running fine then suddenly just felt like it lost all pull and the engine stopped. It was not abrupt, but it did stop pretty quickly. This time it did not fire back up at all. I know the ritual starting procedure and she usually starts up 1st or 2nd kick. It feels like it is not going all the way through the normal stroke. I can use the decomp lever and it will go through so it is not locked up. Please help. :thumbsup:
I am supposed to race a hare scramble this weekend but it looks like that may be a lost cause. Thanks for any advice or a starting point. :bonk:

  • Batmandog

Posted February 23, 2006 - 05:39 PM

#2

I was riding my 426 at the track this afternoon. Something major happened. :bonk:
I was going through a small whop section and the bike stalled. It died kind of weird while I was in 3rd gear or so and one the gas and it just died. I stopped and after a few of the ritual kicks it fired up. :thumbsup:
Ran for another 30 minutes or so just fine. Was riding in 4th and on the gas and it did the exact same thing.
It almost threw me over the bars it happened so fast. It was running fine then suddenly just felt like it lost all pull and the engine stopped. It was not abrupt, but it did stop pretty quickly. This time it did not fire back up at all. I know the ritual starting procedure and she usually starts up 1st or 2nd kick. It feels like it is not going all the way through the normal stroke. I can use the decomp lever and it will go through so it is not locked up. Please help. :thumbsup:
I am supposed to race a hare scramble this weekend but it looks like that may be a lost cause. Thanks for any advice or a starting point. :bonk:

It feels different when you kick it over ? ..As in not normal ?

  • beasleys

Posted February 23, 2006 - 05:47 PM

#3

No, it does not feel normal when you kick it over.
Normally I could take to right past tdc with the decomp and then kick it all the way through the stroke. The kick starter would almost hit the footpeg before it would stop. Now I can do the same thing with the decomp taking it right past tdc bring it back to the top to kick it through and it will only go down maybe 1/2 to 3/4 of the way through the stroke. It feels as if you are never completing the stroke on the bike so it is never going to fire. Please any advice I will take it. Thanks :thumbsup:

  • Batmandog

Posted February 23, 2006 - 06:17 PM

#4

No, it does not feel normal when you kick it over.
Normally I could take to right past tdc with the decomp and then kick it all the way through the stroke. The kick starter would almost hit the footpeg before it would stop. Now I can do the same thing with the decomp taking it right past tdc bring it back to the top to kick it through and it will only go down maybe 1/2 to 3/4 of the way through the stroke. It feels as if you are never completing the stroke on the bike so it is never going to fire. Please any advice I will take it. Thanks :thumbsup:

Sounds mechanical .
1)Pull the spark plug and turn it over by hand to get a feel for what's stopping it up . Possibly something broken on the clutch/kickstart side ...but since it stalled twice I'm thinking something else is going on .
2)Try draining some oil from the engine drain and look for metal .
3)You're probably going to wind up pulling one or both engine covers to investigate .
Like I said , sounds mechanical . Time for visual inspect , start with easy - hand crank and look/listen/feel> check oil for metal>pull covers and look .
Happy hunting . You're about to learn something about motorcycle powerplants !

  • beasleys

Posted February 23, 2006 - 06:29 PM

#5

Thanks. I am going to start breaking it down tommorrow afternoon. I will let you know what I find. :thumbsup:

  • PumpkinHumper

Posted February 23, 2006 - 07:01 PM

#6

aside from the strange kicking thing you talk about try looking at 2 differant things that would explain the stalling.

1. the compression release cable. If its too tight or routed wrong it can open the valve when you turn the bars and the bike can stall. Hard one to diagnose sometimes.

2. Check the gas tank vent line / one way check valve. I have seen those get plugged. It will run for a while and stall as the tank builds a vacuume in it because it aint venting. Let it sit for a minute and it fires right up.

But as you said it may be something mechanical inside. But if it kicks over and has compression I wonder what it could be. Thats an odd symptom.

  • beasleys

Posted February 24, 2006 - 01:46 PM

#7

This is what I have found so far.
I removed the spark plug and it had some carbon but nothing to bad.
I ran through the stroke by hand with the spark plug out and it has no binding at all. I removed the valve cover and as I am cycling it through everything looks good. There is no scoring on the cams and there is good oil there. If I cycle it and watch each valve work the valve retainers are moving up and down freely which should mean no valve springs are broken.
I put everything back together. Tryed to start it. Did not work!! Same time would cycle trough with the decomp. but after you took it past tdc it would stop 1/2 way down.
I have almost ruled out the clutch/kick start thing because it is cycling fine with the decomp in. If it was the clutch or kick start then it would bind up then to no matter if the decomp was in or out.
Please help I am completely lost. I am at this point going back in to the top end to look around again.

  • Batmandog

Posted February 24, 2006 - 02:11 PM

#8

This is what I have found so far.
I removed the spark plug and it had some carbon but nothing to bad.
I ran through the stroke by hand with the spark plug out and it has no binding at all. I removed the valve cover and as I am cycling it through everything looks good. There is no scoring on the cams and there is good oil there. If I cycle it and watch each valve work the valve retainers are moving up and down freely which should mean no valve springs are broken.
I put everything back together. Tryed to start it. Did not work!! Same time would cycle trough with the decomp. but after you took it past tdc it would stop 1/2 way down.
I have almost ruled out the clutch/kick start thing because it is cycling fine with the decomp in. If it was the clutch or kick start then it would bind up then to no matter if the decomp was in or out.
Please help I am completely lost. I am at this point going back in to the top end to look around again.

Take an oil sample ..you might as well drain it all actually - use a clean pan and check for metal .
While you have the valve cover off check the valve timing , watch the cam chain for looseness and then also pull the cam chain tensioner and check it .
Do these one at a time , it'll keep you from get all spun up .

  • Punisher660

Posted February 24, 2006 - 02:20 PM

#9

It almost sounds like a ring - same symptoms when I lost the top end on my CR500 :thumbsup:

You are able to kick it, so its not tatoally seized, but it sounds like something wrong with the compression

  • beasleys

Posted February 24, 2006 - 03:58 PM

#10

UPDATE!!
I have pulled the clutch cover and everthing looks to be normal with a visual inspection.
I repulled the valve cover and checked the TDC to make sure that it aligned at the 2 cams and on the flywheel. It was good.
I removed the spark plug and checked the spark and it was good.
We kicked it over with the valve cover off still using the starting "ritual", and watched the valves. The point at which it is binding up is after the intake valves have closed on the up stoke of the compression cycle about 1/2 to 3/4 up it binds. If you stand on the kick starter at this point it will slowly go past the "bind" after 5-10 seconds of strong pressure. With the valve cover off you can here a slight hiss like air leaking out of the cyclinder.
Could it be the rings???

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  • BC61

Posted February 24, 2006 - 05:07 PM

#11

Have you checked the oil yet as others have suggested? Best thing to do is pull the filter.

The binding symptom as you try to turn it over suggests the rod bearing is probably the culpret.

  • Batmandog

Posted February 24, 2006 - 05:27 PM

#12

UPDATE!!
I have pulled the clutch cover and everthing looks to be normal with a visual inspection.
I repulled the valve cover and checked the TDC to make sure that it aligned at the 2 cams and on the flywheel. It was good.
I removed the spark plug and checked the spark and it was good.
We kicked it over with the valve cover off still using the starting "ritual", and watched the valves. The point at which it is binding up is after the intake valves have closed on the up stoke of the compression cycle about 1/2 to 3/4 up it binds. If you stand on the kick starter at this point it will slowly go past the "bind" after 5-10 seconds of strong pressure. With the valve cover off you can here a slight hiss like air leaking out of the cyclinder.
Could it be the rings???

It should get stiffer after the In valves close (with decomp lever NOT pulled) and you might hear air leaking through the valves if they're a little leaky and also ring gaps .
You need to determine whether or not there is mechanical binding . If it kicks over easily with the spark plug removed I'd say it's more or less normal mechanically ...but you still need to look at the cam chain tensioner too ....I'm just a little thrown by you feeling that it doesn't feel right when you kick it over , I'm assuming that you know what it's supposed to feel like and if it feels wrong to you , it probably is wrong .
Back to work !

  • Batmandog

Posted February 24, 2006 - 05:36 PM

#13

Have you checked the oil yet as others have suggested? Best thing to do is pull the filter.

The binding symptom as you try to turn it over suggests the rod bearing is probably the culpret.

Good call !
To check the rod bearing ; remove spark plug , bring piston (hand crank) up to and then a bit past top dead center - the idea is to get piston moving on the down stroke - then get a screwdriver long enough to push the piston down with through the plug hole - push on the piston , if moves easily for about a 1 or 2 mm then stops w/a little thunk then you've got rod bearing issues .

  • beasleys

Posted February 24, 2006 - 05:50 PM

#14

I have checked the oil by pulling the oil filter. There was little to no metal particles in it.

  • beasleys

Posted February 24, 2006 - 05:54 PM

#15

I am not sure what you mean by if I know what it should feel like when kicking it over. If I had to describe what it feels like when it binds is like it is hydro locked. It is a little spongy but I can definetly not kick it through. If it is the rod bearing wouldn't it bind all the time? It is not binding on the exhaust stroke just the compression stroke. Just asking.

Thanks for all the help keep it coming.

I am almost to the point where I am going to pull the head off.

  • bg10459

Posted February 24, 2006 - 06:01 PM

#16

Yep, similar symptoms as when I blew the motor in my CR250. It would occasionally spin freely and then bind up. The fact that it occasionally spun freely lead me to believe it was a top end issue, but when I pulled the cylinder, it still looked good. It was then I found that it was the crank rod bearing. The pieces of the bearing race would sometimes slip into a void and let it spin, and other times they would jam between the bearings, rod and pin.
Pull the plug and spin the crank a bunch of times. If you still get the binding, there's your answer.
The only thing is, the consistency of where you get the binding leads me to believe it may be a valve issue. But you said they're all moving. Could you have bent a valve and maybe it's not moving as far as it should? :thumbsup:

  • beasleys

Posted February 24, 2006 - 06:40 PM

#17

It is defenitly binding in the same place everytime. I don't think that it is a valve problem but I am no expert for sure.
I just checked the cam chain tensioner and seems to be fine.
I did not find any "lose" spots on the timing chain as I cycled the motor through. I think I am about to pull the head and the jug off an have a look around. The only problem is if I do that then I will not be able to cycle it anymore to check things.

Does any one have any other suggestions. :thumbsup:

Thanks alot! :thumbsup:

  • stknrdr

Posted February 24, 2006 - 07:05 PM

#18

Well heres what I think...I dont think youve got anything wrong with your engine ....when the valves are all closed its supposed to get harder to kick and you are supposed to hear hissing. I would look for simpler and cheaper things first...make sure your vent hose coming off your fuel filler cap isnt kinked or blocked - stuff like that...I havent heard anybody mention spark yet. You got spark? could be something simple like a shorted wire or busted kill switch.

Spark or fuel is usually the culprit...shine a flashlight into your carb and twist the throttle and see if you see fuel. Or just listen you should hear it squirt. pull the plug and see if you have spark.

Usually when you lose a valve or a topend or a bearing you hear banging and clunking and the thing never runs again. Your deal sounds a lot simpler.

  • beasleys

Posted February 24, 2006 - 07:31 PM

#19

I don't think the problem has anything to do with spark for sure. As I said in an earlier post I tested the spark and it is good.
As for the feul I think that might be the root of the evil but not what is wrong now. I think the bike was running real lean its last few seconds. I was in deep sand and the bike started to bog so I got on the throttle harder witch is when it died. I think that when it started to bog it may have had detonation and when I got on the throttle I just pushed it that much further. And killed it. I am in the process of taking the head off right now.
Please keep the info coming I am open for any ideas.
Thanks :thumbsup:

  • beasleys

Posted February 24, 2006 - 08:54 PM

#20

UPDATE #13
I have the motor apart.
I took the cams out of the head.
I took the head out of the bike.
I took the jug off of the motor.
There appears to be no damage on the head or piston/rings. :thumbsup: They were pretty covered in carbon but all of it has cleaned off pretty easily.
The only thing that I see that could possibly be wrong is that there is a heat stress bluish color on the crank on the kickstart side right next at the base of the rod. :bonk:
I did not take the bottem end apart any further than that and that is all that I see. Please keep the advice coming.
Thanks :thumbsup:





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