Jump to content

97 Yz250 Starting Issues..Help Needed

Recommended Posts

Hi. I have a 1997 Yz250 that wont start after having it running beautifully 2 times, and then dying after a minute or so, as if i had pressed the killswitch. 

I have tried a few new plugs and all had a good spark when grounded to the motor casing. Also thoroughly cleaned carb, nothing seems clogged. Got a clean filter too. 

Sometimes hard to kick over, seems like its got good compression, but backfires frequently. It wants to run after most kicks but barely idles for 5 seconds and dies! Im wondering if my reeds could cause it because they dont look too sharp. 

Any help and suggestions for a solution would be much appreciated. Thanks!

Share this post


Link to post
Share on other sites

What you mean reeds don't look good? Broken?  Chipped?  Or melted?  Hard to kick over sometimes doesn't sound good. Peice of reed down there or rod,crank bearing going bad possibly.  

Edited by Motox367

Share this post


Link to post
Share on other sites

Reeds have no chips of any kind but have space where i can see light through them, does 1mm space cause any problems? Im stumped by how it wants to run but always dies in seconds. I feel like something is killing my spark! Heres what my reeds look like. 

20170626_223529.jpg

Share this post


Link to post
Share on other sites

No I haven't checked the timing, im not really sure how that is done. 

I figured the space between was slightly a little too much, would that cause it to backfire when kicking over though?

Share this post


Link to post
Share on other sites

What does your spark plug look like when you take it out after trying to start it?   Flip the reeds over if you are worried about them.   

Edited by ossagp

Share this post


Link to post
Share on other sites

Its always wet, smells like gasoline but has nothing burnt on it! 

Both sides of reeds have basically the same gap, would it make a difference?

Share this post


Link to post
Share on other sites

My bike ran fine with reeds looking like yours. I'd say your problem is ignition based. A friend had his magnets in the flywheel get out of position and had similar problems as you. Was not an yz though. Check the timing and measure the electrical components resistence. 

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Reply with:


×