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anyone ever have a clutch basket gear come loose?

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What happened? my 2004 yz250 has a bit of knock at idle and it sounds like the clutch area, I've replaced the top end. the crank and rod bearings are good.

The loose gear and a badly notched basket is all I can find wrong. I can get a .009" feeler gauge nearly all the way around between the gear and basket, a .015" gauge at one spot. I bought a used hinson basket in pretty good shape and a used clutch kit in better shape than mine. I put the motor back in yesterday its ready to start I just need to repack the silencer.. going to be disappointed if it still sounds like this

Edited by yz250474

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What happened? my 2004 yz250 has a bit of knock at idle and it sounds like the clutch area, I've replaced the top end. the crank and rod bearings are good.

The loose gear and a badly notched basket is all I can find wrong. I can get a .009" feeler gauge nearly all the way around between the gear and basket, a .015" gauge at one spot. I bought a used hinson basket in pretty good shape and a used clutch kit in better shape than mine. I put the motor back in yesterday its ready to start I just need to repack the silencer.. just wondering if anyone here had it happened?

Never had one come loose, but I forgot to tighten one once after a complete top/ bottom rebuild :(

One the first start it ran for about 6 seconds then the gear ran axially outward on the shaft and bound against the inner clutch cover. The motor locked up and it cracked the clutch cover. Believe it or not it was a relief when I discovered the problem. $140 for a new clutch cover and I was back in business. At first I thought the bearings piled up or something...lol.

It was one of those things where I made a mental note....."I'll tighten that later"....lol. Live and learn...

EDIT: I was referring to the primary drive gear that drives the clutch basket.....not the gear on the basket itself....

Edited by Fattonz

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Never had one come loose, but I forgot to tighten one once after a complete top/ bottom rebuild :(

One the first start it ran for about 6 seconds then the gear ran axially outward on the shaft and bound against the inner clutch cover. The motor locked up and it cracked the clutch cover. Believe it or not it was a relief when I discovered the problem. $140 for a new clutch cover and I was back in business. At first I thought the bearings piled up or something...lol.

It was one of those things where I made a mental note....."I'll tighten that later"....lol. Live and learn...

Lol I've been staring in space the past 2 days, and my girlfriend is like " are you listening to me?" and I'm like " I'm trying to make sure I tightened everything" lol

Atleast it won't worse for you.

Edited by yz250474
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I was trying to put this somewhere that people with all makes and models could see it, I've already talked about this thread here.. so if a mod could move it, I would appreciate it.

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The gear is riveted to the basket on my yz250, I can get a .009" feeler gauge almost all the way around between the gear and basket, one spot I can get a .015" gauge in it. my yz has been making a lot of noise and Im hoping this is why, its the only thing I can find. I bought a used hison basket in pretty good shape and I put the motor back in,. its ready to start but will probably be this weekend before I can start it.. do you guys think this is causing all the racket?

Edited by yz250474

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No, I don't think its your clutch basket or has anything to do with the clutch.

Is this bike new to you or have you had it a while and this is a new noise that just started?

It sounds like a typical 2 stroke to me.

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That noise sounds exactly like your crankshaft big end connecting rod bearing is ready to let loose. A quick test to see if it's your clutch would be to, while its running, pull in the lever. If the noise doesn't change, it's your crank. My bike made this same exact noise for a while, and I decided to race it one more race, before pulling it apart. The bike lasted half the race before the bearing let go. It cost me a crank, bearings, piston kit, and a replate. If the noise does not change while pulling in the clutch lever, stop running the bike, tear the topend off, check the crank, and replace if needed, before it costs you hundreds of dollars more

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Is the clutch basket suppose to have any play (if I grab it like you would to check a car tire) it has a small amount of play?

 

Yes.  There are rubber dampers between the basket and the gear.  But not too much. 

 

cltch_9.JPG

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That noise sounds exactly like your crankshaft big end connecting rod bearing is ready to let loose. A quick test to see if it's your clutch would be to, while its running, pull in the lever. If the noise doesn't change, it's your crank. My bike made this same exact noise for a while, and I decided to race it one more race, before pulling it apart. The bike lasted half the race before the bearing let go. It cost me a crank, bearings, piston kit, and a replate. If the noise does not change while pulling in the clutch lever, stop running the bike, tear the topend off, check the crank, and replace if needed, before it costs you hundreds of dollars more

I checked the crank and rod bearings when I changed the top end they are fine. I tried pulling the clutch lever in but no difference

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Sounds just like my yz250....running cold, on the stand, with a wiesco piston, 30 hours on it.

 

On my bike I chalked it up as a little bit of piston slap until everything heats up.

 

Go ride it hard for 10 mins and I guarantee the sound gets quieter. 

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Yes.  There are rubber dampers between the basket and the gear.  But not too much. 

 

cltch_9.JPG[/quote

I mean if you pull the top of the basket away from the case and push the bottom of the basket towards the case.. mine has very little play if you do that.

I should also mention the clutch fibers was hitting the inside of the outter clutch cover its like 3 grooves nearly all the way around the cover.. not real deep tho. Im thinking beings the basket was so notched it was letting the fibers hit the cover?

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Sounds just like my yz250....running cold, on the stand, with a wiesco piston, 30 hours on it.

 

On my bike I chalked it up as a little bit of piston slap until everything heats up.

 

Go ride it hard for 10 mins and I guarantee the sound gets quieter.

Ill keep that in mind, if it still sounds the same I'm probably just going to ride because I can't find nothing else wrong

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OP - YES, I've had one come loose, not on my YZ but an older Yamaha 2t..  The rivets were loosening and made a "clack" every time the engine fired and getting down by the motor, you could hear the sound seemed to come from the side cover, not the top end.  After taking the side case off, I could grab on the bottom of the clutch basket and pull up and down and see the slop.  To be honest, I figured if that's ALL that's wrong with the basket, I'll just peen the rivets to tighten it up.  There was minimal grooving in the basket fingers.  YZ and TS work got in the way and I haven't returned to that project yet.  BTW - I wasn't too worried about tightening up the basket because some bikes have NO cushioning in the clutch basket.  

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OP - YES, I've had one come loose, not on my YZ but an older Yamaha 2t..  The rivets were loosening and made a "clack" every time the engine fired and getting down by the motor, you could hear the sound seemed to come from the side cover, not the top end.  After taking the side case off, I could grab on the bottom of the clutch basket and pull up and down and see the slop.  To be honest, I figured if that's ALL that's wrong with the basket, I'll just peen the rivets to tighten it up.  There was minimal grooving in the basket fingers.  YZ and TS work got in the way and I haven't returned to that project yet.  BTW - I wasn't too worried about tightening up the basket because some bikes have NO cushioning in the clutch basket.

Thanks for the reply, Im going to upload another video when I get it runnin.

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This has been mentioned before.  YZ's make a little more noise idling than, for example, a street bike.  But a lot of that is the whine of the straight-cut primary gears.  Then there's the top end noise from race bike clearances.  I questioned it too when I first got my YZ.  

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