In all honest it seems as though an actual bearing would be the real solution... doubt kawi will ever do it though, this is kinda a rare situation I think?

 

When it "hiccups" it is a "locking up" sound from the engine. I have a Shorai lithium battery that is supposed to stay at 13-14 volts. It turns the engine over pretty quickly.

 

I looked at needle bearings for it. I could probably find some that I could mount in there if I bored the cases out some. My plan now is to just replace the crankcase and stator cover, keep track of the "hiccups", and if I experience a few, pull the cover off to inspect the bushings.. If the bushings look worn they should be easy enough to change, as long as they dont wear as far out as mine did. the bushings are only $4 from Kawi.

Athena wrote me back and said that the gasket kit for the "09" engine is the same.
"Athena Spa wrote, in response to Dan:

Dan, good news! P400250850049 fits also 2007 KLX 250 S model.

Dan (unregistered) wrote:

Will this fit the 2007 model KLX250s? Do you know if there are any differences between the 2007 and the 2009 engines? Thank you "

 

Dan,

Just out of curiosity. When the "locking up" sounds occurred, did the engine actually stop turning over? In other words, do you have to release the starter button and hit the button again to get the engine turning?

Yea thats the battery I want ... definitely not a battery issue. hmmm I was thinking the octane thing too when I first started reading this thread last night, but I don't feel it is the total problem either. It's crazy looking back at those pics how the spindle on the idler gear just started boring its way to a new home...

 

For the $150 I spent on the eBay crankcase I think I'm better off. My friend did say that if we had the room we could mill around the outside of that boss and fit a steel collar to contain that crack. Like I said, I feel better with the deal i found.

 

Yeah the hiccup reverses the whole works. I let off the button when it does this. crank, crank , chu-chunk all stop, let off the button, then hit the starter again.

 

Thanks Dan,

I know exactly what your talking about and what exactly to keep an eye on now... I honestly can't remember if this is the same thing I have encountered on rare occasions with my Klx or some of my mopeds either way I'll keep an eye on it from now on.

The route your going sounds like the best at the moment, keeping with the oem bushing will be just fine... but apparently it's just one more thing to check on from time to time.

I got the .pdf copy of the service manual... maybe I'll add this to the "things to check" list.

 

That's an interesting deal there, dan. I don't know...I'm not sure it's octane related...especially at startup. You can read lots of data and testing about octane and its effect on starting, under load, and antiknock qualities. I kind of doubt that 87 octane in our bike would cause that notable a kickback on startup. Wouldn't we hear more cases of this? Hard starting is one thing, but that chunking metallic sound seems obviously different. Any chance the problem is in the starter and gear interface?

 

I am almost certain that the problem didn't originate in the starter, or related gear train. This problem is separate from the "hard starting" many KLX (including mine in the past) experience. It's more of a low rpm thing, like when starting the bike, or when the bike is about to stall because someone is going too slow, and hasn't pulled the clutch in. The chunking sound is the engine trying to go in reverse, and all the connected gears protesting. Honestly I think the clutch gear behind the starter is the only one that cant go in reverse.
When it happens, it sounds like a premature detonation sending, or trying to send, the crankshaft and connected items in the wrong direction. One of the more fragile items is the combination of gears between the flywheel and the starter.
Octane is just a guess, I've read about the higher octanes being resistant to premature detonation. I rarely run premium, my bike sounds like its prematurely detonating, so that's where I got the octane thing.

 

I think the sound your hearing is the ACR unit. It kicks in at very low rpm, and sounds just like your describing. I think you just had a defective something, did you buy the bike new?