Starting problem. Yzf 426

6 replies to this topic
  • kubamtx

Posted July 14, 2007 - 05:29 AM


I need a little help.
My 01 yzf 426 always started like it should. When cold using cold choke and 2 kicks, and when warm with 1 kick and after falling on hot choke with 1 kick.
Yesterday I rode a little on the track and in forest. I stoped and after 10 minutes wanted to start my bike, and nothing. I used hot start and it started. Then in forest I stoped to check if it will start and it started (but there was only 1 minute break). Today I went to garage and tried to start my bike (cold choke). It was impossible. I changed the plug and tried once again(cold choke), and nothing. Then I used hot start and after 5 kicks it made a noise. Next kick it started.
Now I don't know why it happens.
Could you give me a hint.
(sorry for my english , I now I make mistakes)

My conclusion is: the plug was poor (on the track),(tomorrow) I flood it. I've changed the plug but the bike was flooded so I flood the next plug using cold choke. Then it started on hot start because it was flooded. Am I right?

But today I'll check if it'll start well when cold.

  • 642MX

Posted July 14, 2007 - 05:41 AM


Check your valve clearances. My 426 started to foul plugs and I found a tight center intake valve. I reshimmed the valve and the fouling went away.

You may want to pull you carb and give it a good cleaning too. :thumbsup:

  • kubamtx

Posted July 14, 2007 - 01:11 PM


Thanks for advice.
Today I found my right intake valve to have 0,08mm of clearance. Is this enought to couse any problems?

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  • grayracer513

Posted July 14, 2007 - 02:42 PM


Probably not, but it needs to be adjusted anyway.

  • Dr.Wilson 154 ( . Y . )

Posted August 05, 2007 - 09:28 PM


if your using stock spark plugs for a 426 they only last for about 2 rides before they start to turn, if i were you i would buy a cr8ek plug for your bike it has 2 electrodes on it and it makes my 426 start first kick if hot or cold, dont even touch the throttle when trying to start it or it floods for sure

  • Fastest1

Posted August 07, 2007 - 05:02 PM


I have a 2000 model but I have had the problem you describe a time or 2. Did you feel like you had much compression / resistance thru the kickstarter? I never was able to track it down as it would disappear as quickly as it came. I always thought it might be a valve not closing all the way (but the valves were always in spec). I am still on the original valvetrain except 1 450 exhaust cam.

  • nos487

Posted August 07, 2007 - 05:12 PM


Check you intake boot( between carb and motor) for leaks. Friends split and I watched him kick it a bunch of times. Replaced ,ok now.

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