After 20 hours of riding

8 replies to this topic
  • yz426em

Posted April 22, 2005 - 09:24 AM


I finished my top end on my bike which included new cams (auto decomp.), piston, rings, etc.. I have about 20 hours on it and it always started right up. Now it seems to be harder to start, probably like 10 kicks and sometimes more.once u get it running its fine and it restarts fine once its warmed up. :naughty:

  • biznet1

Posted April 22, 2005 - 03:15 PM


It could be the temperature change that is coincidently occuring right now. Try some jetting adjustments.

  • mark794

Posted April 22, 2005 - 03:37 PM


Try disconnecting the the neutral switch at the 6 pin connector (light blue wire male end) on the main harness between the tank and radiator. I did it to mine that always started on the 3rd kick and now it starts 1st kick. You can get more detailed info about it at Motomans site under tech articles.

  • moto1020

Posted April 22, 2005 - 10:04 PM


have you checked your valve adjustment?

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  • BlindSide

Posted April 23, 2005 - 12:55 AM


20 hours ? It's just broke in. You're valves aren't even seated. Maybe I read wrong....but a complete rebuild after 20 hours ?

  • condog_aus

Posted April 23, 2005 - 01:52 AM


Yeah im a bit confused what your saying too. Have you rebuilt after only 20hrs or have you done 20hrs since the rebuild.

If youve done the former then thats pretty excessive maintanance, but it will loosen up after a about 10hours and get heaps easier to start. If its the later then it should have loosened up since the rebuild and you may have a timing problem. Are you sure got the cams in the right spot. Also what cams did you put in. Did they have the auto decomp lobe.

And yeh the blue wire mod really does help starting, especially restarts during races.

  • yz426em

Posted April 23, 2005 - 09:38 AM


I rebuilt the motor and now i have about 20 hours on since the rebuild. it did always started fine now its getting harder to start. I put hot cams in it intake and exhaust with the auto decomp. exh cam. Any help is great thanks guys

  • sirthumpalot

Posted April 23, 2005 - 10:05 AM


1) If the temp has changed recently, check your jetting

2) Check your valve clearances. You just finished a break-in after a rebuild so you're due to check them anyway. If the valves tighten up and hang open it can make starting difficult, and can really affect the idle and low speed power. Leave them this way too long and it will burn the valves and/or seats and you'll be taking it apart again. Not sure if the valves are the cause, but it's so easy to check the clearance that I can't think of a good reason not to.

  • BlindSide

Posted April 23, 2005 - 10:36 PM


Sorry I misread I guess, but yes, as stated above, check your valve tolerances.

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