Help!! Decompression at start problem


8 replies to this topic
  • beasleys

Posted October 17, 2005 - 04:27 PM

#1

:banghead: I went out today to work on my 01 426 and I installed a White Brothers E-series exhaust. I got it put on with no problem and went to start the bike. I have not started it in about 7-8 days. I have never had one problem starting the bike. I perform the "ritual" and she fires right up first or second kick every time. When I went to start it, It went all the way through the stroke. It did get tight at TDC but I was able to kick through it with out even trying to hard. I immediately checked the decompression lever looks good. I checked valve clearances, They were good.
After checking the clearances I felt comfortable enough to try to start it and it did fire right up first kick. I can still push it all the way through the stroke with out to much of a problem. Once I got it started it ran fine. I have no clue what could be wrong except maybe this :lol:
I installed a Rekluse 2 weeks ago and got in one good ride on it and during my first Hare Scramble it burnt up my stock clutch plates. I know that it should not if adjusted properly but I think that it had never been replaced in a 4 year old bike and it was just time for them to go. With that said would the plates being worn severely in my clutch make the engine do what was described above. I am awaiting new clutch plates and they should be here wed. at the latest. Please help with any info or advice you have thanks in advance. :banghead:

  • beasleys

Posted October 18, 2005 - 01:15 PM

#2

Can anyone help I am lost with this still.
:banghead:

  • cowboyona426

Posted October 18, 2005 - 01:41 PM

#3

Have you tried it again since you started it? You might try unhooking the decomp cable (if you still have one installed) and see if that helps. Other than that, I don't have any advice. It seems like my bike did that once then the problem just went away- maybe yours will too.

  • beasleys

Posted October 18, 2005 - 01:55 PM

#4

I will try disconnecting that lever tonight maybe it will work. Thanks :banghead:

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  • DaveJ

Posted October 18, 2005 - 02:44 PM

#5

It's most likely the seal around the valves, which is no longer a problem when the bike is warmed up.

Run it for a few minutes and you'll see what I mean. I have had the same concern.

Assuming, as you noted, that all other specs are in line.

It may also be a good idea to park the valves when you shut it down for extended periods...piston at or near TDC. I don't know if this will resolve it, but it can't hurt. Try it.

DaveJ

  • beasleys

Posted October 18, 2005 - 05:00 PM

#6

If it is leaking around the valves what is the fix? All valves are with in tolerance.

  • DaveJ

Posted October 18, 2005 - 05:35 PM

#7

Well, I'm kind of speculating here.

After many hours on an 00, I had the same problem. I did what you did and checked all the valves and the de-comp.

Everything was fine. So before I tried starting it up, I tore it down for a full inspection. Of course the cylinder and piston were not perfect, but nothing was really that bad. The only thing I could find wrong was some leaking between a few of the valves and the seats, (simple liquid test).

After a complete rebuild, and a few more hours of riding, I had the same problem. This time I ignored it and started the bike up. After a few minutes on the track everything was back to normal.

Now....I had read somewhere (could have been here or in one of the mags) that particles can build up between the valve and the seat when the bike sits for extended periods. Some sort of reaction with the fuel and the material of the valve...if I remember correctly. This keeps the valve from fully seating once you cycle it back in place, but clears away once the bike is ran for a little while.

Sorry that I don't have a more solid answer.

DaveJ

  • Shawn_Mc

Posted October 19, 2005 - 10:07 AM

#8

Well, I'm kind of speculating here.

After many hours on an 00, I had the same problem. I did what you did and checked all the valves and the de-comp.

Everything was fine. So before I tried starting it up, I tore it down for a full inspection. Of course the cylinder and piston were not perfect, but nothing was really that bad. The only thing I could find wrong was some leaking between a few of the valves and the seats, (simple liquid test).

After a complete rebuild, and a few more hours of riding, I had the same problem. This time I ignored it and started the bike up. After a few minutes on the track everything was back to normal.

Now....I had read somewhere (could have been here or in one of the mags) that particles can build up between the valve and the seat when the bike sits for extended periods. Some sort of reaction with the fuel and the material of the valve...if I remember correctly. This keeps the valve from fully seating once you cycle it back in place, but clears away once the bike is ran for a little while.

Sorry that I don't have a more solid answer.

DaveJ



I had the exact same experience on my 426. What I started doing to avoid it was: I'd push it around to till I hit the compression stroke (with the kicker), leak it passed a bit with the decompressor and then store it. That way all the valves are all closed and it doesnt get any air past the valves and the seats are in contact so stuff can grow or develop there. Once I started doing that simple routine, never once had the thing act like a valve was hung again. :banghead:

  • beasleys

Posted October 19, 2005 - 11:00 AM

#9

Thanks everyone. Looks like I may be able to still ride this weekend!! :banghead:





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