01 426 starting worries

11 replies to this topic
  • tri501

Posted October 07, 2006 - 12:53 AM


Went out to go for a ride today. Got the bike out of the shed. All geared up. Jump on bike to start it and warm it up. Turn on choke, hold in decomp lever and wind though 3-4 times, start to wind it back to tdc, goes straight past, try again, straight past. Thinking &%$#@!. Wind to where i think tdc is and kick. Fires first go runs fine went riding, no dramas. anyone have any idea why it would do this? Have owned the bike for 2 months, has never done it before, and it ran fine. today. Any help appreciated.

  • GONE1445

Posted October 07, 2006 - 09:05 AM


mine does it sometimes so does my uncles both 2001 yz426's and my uncle has owned his since new

I don't know why it does this usually if I pull the decomp lever and let it snap back a couple times it stops

usually it only does it if it doesn't start in the first couple of kicks (when its not quite warm but not cold either, hate it)

  • kizzle426

Posted October 07, 2006 - 10:35 AM


It sounds like you may be losing compression. I'm not a mechanic but that is sometimes the culprit. I can't kick through mine at all without hitting tdc and pulling the decomp lever. Could possibly be a valve issue. Just a thought. :devil:

  • tri501

Posted October 08, 2006 - 02:35 AM


went for another ride today. bike ran perfectly. got to tdc and had to use decomp everytime. should i be worried?

  • Slowmotion426

Posted October 08, 2006 - 03:02 AM


Mine does that occasionally.

  • gem

Posted October 08, 2006 - 03:10 AM


I have had the same suprising behavior, with my 426 it has happened twice since I have owned it(one year) and it occurs only when the bike has sat for a while. However the bike does start and runs just fine with tdc easy to find after the first start. Yes this does make me nervous so hopefully some of the 426 masters, or maybe the all-knowing magi of the motorcycle, greyracer513 could sooth our four stroke fears.

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  • Satch0922

Posted October 08, 2006 - 04:10 AM


Sometimes the compression release will hang. Remove the compression release mechanism from the head and clean. The make sure you lube the compression release cable.

  • tri501

Posted October 09, 2006 - 01:47 AM


thanks for the feedback. good to know i'm not the only one. will have to keep an eye on it. thankyou all.

  • speddie3

Posted October 09, 2006 - 08:12 AM


Cant say that mine has ever doen that yet, and I've had it for a while now. Ever checked your valve clearances??? might have a tight valve that didn't close all the way when it was cold. Or as Satch0922 said, check out the decomp system and make sure its all clean and nothing is hanging up that might cuase it not to close all the way.

  • YZ426F Rider

Posted October 09, 2006 - 08:32 AM


Sometimes the compression release will hang. Remove the compression release mechanism from the head and clean. The make sure you lube the compression release cable.

That was my first thought since you said it ran fine once started and that it continues to run fine. Make sure your entire compression release system from the lever to the head is clean and lubed.

  • grayracer513

Posted October 09, 2006 - 09:00 AM


A valve can occasionally "stick" off the seat due to carbon on the stem, or a chip on the valve face. Then, once you knock it off, the bike runs like it never had a problem.

  • racer511

Posted October 09, 2006 - 09:08 AM


my dad had a problem with his 426 diing on him while riding and starting. it would just die. we found out that the way the decompression lever and cable had been routed it was causing the cable to pull itself when you turned the bars and the bike would loose all compression and die of course.

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