realy i am sooooooo dumb......

before one year i lost cylinder, piston and head, for an unexpected piston-valve contact of at my klx 250 model 1997 (completeley perfect stock timing, and stock engine). I didnt take in mind why the bike did this....

bought a 2010 head, piston and cyllinder. KEPT the old valve springs, because the knew one hasent any.

the head was just perfect before installation, perfect piston-valve clearence, valve lap, valve guide clearence, all perfect.

After running for about 1000 miles, with perfect eneos 15w50 ester base oil, BAMMMM.....

took the head appart, again a huge hall in the piston, destroyed cyllinder and comletely ruind head....

Messured the valve springs, tooo soft, and way shorter the "replace" point...

Please try not to be so stupid like me......

I am so , i am gonna buy a brand new KX450F and a ducati monster 696!!! (dual sport as it sould be) Never again keeping more than five year an engine equipted vehicle.....

 

Well...that was interesting in so many ways.

 

Hey now!! Don't blame the machine when as the maintainer I'd be looking inward. Sheesh you had the top rebuilt, you had the culprit it your hands...tsk tsk
Good luck with the new bikes!!

 

Are you saying the valve springs failed and caused engine failure?

I'm curious why you blame the bike, when you rebuilt the bike and decided against changing 15 year old valve springs, then get angry at the make/model. Am I missing something?

 

LOL!...I wondered the same thing. Well, at least the 696 won't have any valve springs to worry about, will it?

 

of course its not a bike' s problem, the problem was mine, like i said i am stupid, although...

when you check the 1995 service-repair manual it doesnt say for checking the valve springs for proper lenghth. That is mentioned to the klx250s (2006-) service manual.... For this of course i blame kawasaki...

but for rebuilding a bike with the same 15 years old valve springs i couldnt blame kawasaki....

this thred intend to make a warning at klx owners that IMO after 10 years they must check the valve springs for faillure... or else they will face same problem as me...

IMO if somone replace OEM cam with a higher lift cam, he must also install harder valve springs

 

Yes, that is very good advice to replace valve springs on an engine with high run time or even just high calendar time when doing any extensive service involving the head. Less than $40 for a set of springs could prove to be cheap insurance for performance...or worse.

Can I assume that perhaps we had a language issue on this thread as far as assessing your situation in your first post?

 

In the first post I heard "I should have replaced the valve springs and didn't. I seriously regret that oversight." I just wasn't sure where the blame should be. Clear now.

Was the timing chain in good shape? Putting a valve through a piston is usually something you hear about on cars when the timing BELT hasn't been properly maintained (replaced regularly).

Point taken, and a seriously expensive oversight indeed.

 

the timing chain was new, cam timing perfect (it run and started perfect for 1000 miles before engine failure)

i am very sad because it was the first time that the bike had enough power....

I like the klx250s, but it is too slow for my needs and i dont want to spent much money for 351 kit, etc.

Now that i am calmed, i am thinking to buy a WR250R with 27HP wheel power and the dual sport character of the klx250S.... Any opinions?

 

I've heard good things about the WR, don't think you can go wrong there.