98 yz400 wont start

7 replies to this topic
  • ryan sully

Posted August 08, 2012 - 07:18 PM


New to the 4 stroke game and to these bikes.
So i got this bike off craigslist and I watched the guy I bought it from start it first kick and rode it around his yard once.Then it suddenly died and we could not get it started again.Got a good deal but I still cant seem to get it started.
checked and its getting spark but changed the plug anyways,has compression, took all the tape of the wires and checked all the connections,drained carb and replaced with new gas. any suggestions?Thanks in advance

Edited by ryan sully, August 08, 2012 - 07:20 PM.

  • corndog

Posted August 08, 2012 - 09:03 PM


Seems like when you lug the thing around until it quits, while you're still giving a bit of gas, you can actually have a flooded condition. I could be wrong, but I'm pretty sure I've experienced that before. Usually the hot start gets her going again. Have you tried the hot start with your hand off the throttle?

  • ryan sully

Posted August 09, 2012 - 05:05 AM


yea ive done the starting process SEVERAL times.

And it didnt just bog down and die when it did.It just suddenly shutoff

Edited by ryan sully, August 09, 2012 - 05:06 AM.

  • mediumdaddy

Posted August 09, 2012 - 06:16 AM


You are braver than me - if i was looking at a bike and it suddenly died and could not be started again, even after all that, I'd have turned tail and run. just me. Try holding the comp,. release in and kicking it 8 or 10 times to clean itself out if its flooded.

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  • ryan sully

Posted August 09, 2012 - 09:18 AM


Tried that and then some lol.might just take it to a shop and let them deal with it

  • Pooley

Posted August 09, 2012 - 12:50 PM


Try checking the float height, as well as the needle valve o-ring. The o-ring will harden up over time and you could be continually flooding the bowl because the ring won't seal. If the bike sits with the fuel petcock off, then starts, but eventually dies with the fuel on, this could be the culprit. Try starting/running with the fuel off for a bit to see if it is a float/needle valve issue.

  • ryan sully

Posted August 09, 2012 - 04:54 PM


ok ill try that when i get off work.Thanks

  • ryan sully

Posted August 10, 2012 - 09:20 PM


it still didnt work.Im completely out of ideas.Just gonna take it to the mechanic.Ill let you guys know what the problem is when I hear back

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