Idler Gear Wobble Video

Video of my idler gear wobble. Not sure if something like this has ever been posted.

When I tried to start my bike last weekend to go for a quick ride to the store, I heard a 'crunch' and then the kick starter locked up. Knowing what problems it can cause, I stopped, put the bike back up on the center stand and knew I needed to take the thing apart. I looked thru the gap b/t the clutch and case about 5 months ago and assumed all was ok due to my gear not having any chipped off teeth, but consider this a fair warning that even if your teeth on your gear are fine, doesn't mean the bushing on the gear doesn't have enough wobble to wreck potential havoc.


Be careful when you are sliding the gear off the shaft, there is a washer in front and a washer behind the gear. My rear washer fell down into the engine pan, but it was easy to get out with a pair of pliers. Needed to change the oil anyway...

Hope this provides folks some insight to change it no matter what. :worthy:

Good job, that's really loose. How hard was it to remove the clutch? Did you use an air impact gun? I need to check mine.

I don't own a impact wrench. Yea i know, i'm behind the times.

I have a 22MM 1/2 inch drive socket and pretty beefy ratchet. I held it while a buddy 'carefully' hit the wrench with a rubber mallet. 3 short hits and it broke loose. I tried getting the clutch off by myself, but wasn't successful, didn't have enough hands to do it carefully. Stepping on the rear brake and putting it in gear and trying to loosen it at the same time doesn't work. At least for me it didn't. :worthy: BTW, the threads on the clutch bolt are normal, not reverse There is a washer between the clutch discs and basket, watch for it, You'll think something fell into the engine but the washer is actually inside the basket and goes b/t the basket and clutch. I confirmed this in the manual. Also, there is NO washer b/t the clutch nut and the actual clutch. Weird, would think there needs to be one but there isn't.

Sounds good, thanks for the info. If I leave the basket and plates together I shouldn't have to deal with the washer you mentioned, correct?

The plates come out as on piece seperate from the basket. I tried to pull them out together and heard the washer fall, its not a big deal just realize that it fell inside the basket and to repostition it when you put it back on. I actually put the basket on, then the washer, then the plates. There is a washer and bushing as well on the shaft, but it stayed on.

I had no indication of an idler gear problem until last week. Glad it didn't happen on the trail or worse yet, haulin' down the road at 60 mph.

So when you replace the gear and bushing, is there no wobble at all? Or is there still some wobble when it's all good? Thanks.

I am getting ready to perform this operation. Thanks for the insights.

I bought my new idler gear from Kawasaki when they were having a 20% off sale on OEM parts. Was ~$60 bucks or something. Even with it being oem, there is a tad bit of wobble, but nothing like my video. So it is NOT a shoehorn fit by any means, but has some slight play. Could be the shaft is worn, but it didn't look like it. The actual OEM gear from kawasaki has a bushing pressed into the center hole, all they have to do is make a better bushing with closer tolerance and the problem will be solved. Maybe they don't b/c the gear doesn't get very good exposure to oil to lube it?? who the heck knows. Its absurd that this problem even exists, but i digress. :worthy: to Kawasaki designers....

So yes, the answer to your question, the new one, if you go w/ an OEM one like I did, will most likely have a 'touch' of wobble.

To add, I just had Brewster do my ACR mod, this proves that the mod, while a MUST have, isn't a failsafe from idler gear malfunction.

Mine wobbled like that to, I never had a problem with it but my bike always started first kick hot or cold. :worthy:

"The kawasaki idler gear, they dont know what there doing" :lol: :lol: :lol::banana: :banana:

I'm in the process of inspecting my idler gear as well. Mine may not wobble as much as divers' but there is still some. Can anyone comment on whether this is about the same amount of wobble in a new OEM idler gear? I'd rather spend the money on something more exciting for this bike, if I can. :worthy:

That's a touch bit more wobble than the new one, but not by much. Its up to you. A broken case is a lot more expensive than the ~$60 idler...

Thanks for the info!

I will reinforce what the OP said. Missing teeth is not the indicator of a problem, it is a possible result.

I bought my KLX with a cracked case and a broken shaft. All the teeth were intact.

From the damage on mine it is obvious that it occured while the bike was running. The fact that a bike starts first kick doesn't mean it is ok with a badly worn bushing.

That's a touch bit more wobble than the new one, but not by much. Its up to you. A broken case is a lot more expensive than the ~$60 idler...

A ktm is cheaper than broken cases to! :worthy:

Where can you find a idler gear for $60 ? Bike Bandit is $76 and change.

Do the washers come with it from Babbitts, it looks like there is a different part # for those. Also since mine is a 2000 would I order one for the A5?

Is this also a problem for a '96 KLX 250?

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