We have only 5-6 hours on a klx 125l and it backfires when you de-cellerate in first or second, rarely in third. It is also hard to get it to idle when cold. Someone suggested to check the valve clearance but I am hesatent to do this myself. I have seen postings about other bikes and valves just not this one. If anyone has pics of their valve work please post them. I would like to do it myself since it is a new bike and I have more than one. Is it difficult? Any special tools I may need? Thanks in advance.

Ryan

 

So I ordered the shop manual for the KLX125 a/b but it is back ordered. Guess bike will sit until I get it.

 

I would take it to the dealer. You should not have any valve clearance change in 5-6 hours of operation.

 

I can't give you much help on that bike on the valves.

But, have you checked the air fuel screws to make sure they are the right turns out? In?

 

Valves were ok. It was the fuel screw. 1/4 from the factory. I'm at 2 now. Runs fine now and MUCH easier to start.
Thanks.

Ryan.

p.s. Much easier to work on than the 250s. Lots of clearance. That part was nice.

 

Another good call by BR, endless knowlege

Glad you got it figured out Ginsu, What altitude are you at?

 

2000 ft. I read somewhere that the fuel screw should be at 2.5 turns and an adjustable needle should be added. I chose 2 turns and it seems to do the trick. I didn't modify the exhaust as suggested by some other forum I read (Thumper Talk??). I will add an aftermarket exhaust this winter.

 

All right man, here's your $20 bucks....lol lol

Glad you got it fixed....It's always easier to start at the easy things.