my yzf ran flawless till now :(

well my bike started like normal 2 kicks then it started to act up funny it wouldnt stay running unless i had it choked and if i gave it any gas, it would die right away if i had choke off it would die to, well neways i some how managed to run it down the road i thought maybe the plug was loaded up, well i got to where we were gonna ride and it just killed on me, same thing again only ran with choke on, and i couldnt give it any gas or shed die so i got it home put it on the stand and decided for the hell of it to kick it to see what happened, and it had barely any compresssion i can kick it all the way through without DC. help me please i need it im new to 4 strokes and im starting to get worried

Have you chacked the valves regularly? Tight intakes can cause poor idle. It sounds more like a carb problem. Maybe take apart the carb and clean it thoroughly with carb cleaner. You could have dirt where it doesn't belong.

I read you post again and now believe the valves are the problem (no compression). Have you ever adjusted them?

[ June 01, 2002: Message edited by: YZ400Court ]

Ditto on Carb and Valves

Also noted and asked by yz400court, no mention of maintenance How often, or has it been done ?

ive only had it about a month and a half im gonna go mess with it today a little.

Well, what did you find??

well i think i might of figured out my prob today i pulled it all apart and everything was so sticky from the carb to the piston and especially the valves, i think i over oiled my air filter and sucked alot of it and gummed up everything, so i guess im gonna try to clean up everything with carb cleaner and put it back together and hopefully it will run, so be careful when oiling those filters, some 1 told to just use just a lil bit of motor oil on em that way if it sucks in a lil it will just burn it anyways and not stick to anything and gum them up, i was using maxima fab 1 spray, once i get it back together, ill let ya know if it run then or not, but im mad cuz i have to miss tomorrows race. :)


Feel free to oil up the filter completely, then take out whatever excess you can. And I always let my newly oiled filter drain over night before using. And don't worry about removing too much oil. Once it's been oiled completely, unless your cleaning it, you can't remove too much oil.


Oil and how much is enough ?

I personally only use about a oz of oil and just make sure I work it in real good.

Some say just soak it and ring out the exxcess

I dont know all I know is I dont have an issue with oiled up carbs from over oil. I have had me Carb apart once, since I got it.

I clean it every ride also....

I put the filter in a 1 gallon bag and put about 2 or 3 oz. of Maxima FFT or Motul filter oil in the bag, squeeze the air out and knead the oil all through the filter. Then I take it out and squeeze the excess oil out of the filter. You cant squeeze too much out. Ya gotta let it dry over night before you start it even if you squeeze it like the neck of the Soma bich that stole your kids bike! These thumpers have such a huge intake pulse that they will suck the oil right out of the filter and possibly the wet filter into the carb.

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