I removed my right side engine cover today to find this:



I've been reading that the early KLX300's suffered from weak idler gears.

It seems the common fix for the weak gear is the ACR mod but, my bike doesn't have ACR it's been removed and in it's place I have a true hot start unit (lever/cable rider operated) that was manufactured by Stroker back in the day.

I looked up the idler gear for my 1997 KLX300:
59051-1120 - GEAR-SPUR,IDLE,28T


And out of curiosity I looked up the idler gear for a 2006 KLX300: 59051-1400 - GEAR-SPUR,28T



I did some digging and sure enough between 2002 and 2003 the part number for the idler gear changed.

So - does anyone know if I can use the newer (assumingly stronger) 2003+ idler gear in my 1997?

Thanks,

Brian

 

In my opinion, the ACR might contribute a small amount to the life of the idler gear, but it is the bushing in the idler gear that wears prematurely which causes the gear to wobble and contact the clutch basket. I don't know what Kawi did to the idler gear in the later models but it worked.

Ride on
Brewster

 

And check the part numbers for the washers on both sides of the idler gear. There may a difference in dimensions.

Ride on
Brewster

 

Thanks Brewster. I thought about the washers last night after I posted.

I went through the fiche for every year KLX300 noting part numbers for hte idler gear system. Here are the part numbers associated with the idler gear in the KLX300 from 1997-2007:


1997 - 2002 KLX300
59051-1120 - Spur (Idler) gear, 28 tooth
92022-1614 - WASHER,17.3X25X0.5
92022-270 - WASHER,17.3X30X1.4
92033-032 - Clip Ring


2003 - 2007 KLX300
59051-1140 - Spur (idler) gear, 28 tooth
92025-1451 - Shim, T=0.7
92025-1451 - Shim, T=0.7
92033-029 - Clip Ring, 18mm

In the kickstart microfiche for 2003, there is a cut away window next to the idler gear that shows the gear, shims and clip ring for 2002. I highly doubt that Kawasaki made any changes to the engine case, etc and the other gears in the kickstart system remain the same part numbers from 1997 - 2007. I imagine Kawasaki did this so someone doesn't inadvertently order the later gear and not use the later shims and clip ring?

If anyone reading this has a disassembled 2003 - 2007 KLX300 engine lying around I'd love to get a few measurements to compare the idler gear setup in my 1997 and confirm that I can indeed use the later parts.

Otherwise, I may just order the later parts and see if they fit.

Brian

 

Hello Brian,
Did you ever figure out if a newer idler gear (2003+) fits the older bikes?
I really need a new gear, but don't want to throw my bike under the bus again...
Thank you in advance!