YZ450 Clutch issue

I just bought a 2003 YZ450F.  Once I got the bike home and started to look it over I found that I can't get the clutch to work.  Neutral works, but any gear I put the bike in and pull the clutch, the rear wheel doesn't spin (I'm not sure if that means the clutch is engaged or disengaged).  In other words, it's always in a gear no matter what I do with the clutch lever.  I've tightened the cable AND loosened the cable with no success.  I can see the cable turning the linkage on the transmission, so it seems like it should be working, it just isn't.  I'm going to presume that something's broken inside the transmission, but since I'm a novice, can anyone give me an idea where to look or what to look for?  I've got a manual on the way (here next week) so that should help, but I want to open it up and take a look at the inside.  Searching the interwebs hasn't been of much help.  Any help would be enormously appreciated.  Thanks in advance!

It's fairly normal for a clutch to "stick" when the engine is cold. If you start it up and pull the clutch in and put it in gear then there is a problem. Once up to temp and you stop the engine you should be able to put the bike in gear pull the clutch and roll it back and fourth at that point. Don't forget to set your clutch lever gap to pivot mount about the thickness of a nickel

If you mean you can't rotate the rear tire by hand with the bike on a stand, in gear with the clutch disengaged (lever pulled in), that's pretty normal.  Wet clutches drag a lot.  The standard to use is whether the bike will go into neutral reasonably easily while idling at a standstill.  If it will, it's good enough.

Thanks all, but I suspect I didn't phrase my question well.  I can't roll the bike when it's in gear by pulling in the clutch (without turning the engine over).  I can't start the bike in gear with the clutch lever pulled because the bike lurches as I'm turning the engine over.  I've warmed the bike up, but if I try to put it in gear from neutral it will lurch badly and die because the clutch isn't working.  I bought a 2002 CR450F as a bookend to the Yamaha and it worrks perfectly, so I'm fairly convinced that this isn't normal.

Next thing to check is the clutch basket. If the previous owner rode it like a 2 stroke chances are the clutch could have fried together or notched the basket badly enough that the plate won't "pop" out of the grooves. In that case you may be able to file the notches out of the basket if they are not too bad. But if it's bad enough to catch the on. The basket is probably toast at that point and need replaced

If the bike has been sitting for a while, this could still be somewhat normal.  As earlier mentioned, the clutch may simply be gummed up a bit, and some ride time may free it up.  Be sure you have adequate free travel at the lever, and get the bike out running for a while.  If it's going to free up, it should do so within a half hour or so. 

 

If not, the plates may be warped, dished, etc., and/or the basket and boss badly notched.

I just bought a 2003 YZ450F. Once I got the bike home and started to look it over I found that I can't get the clutch to work. Neutral works, but any gear I put the bike in and pull the clutch, the rear wheel doesn't spin (I'm not sure if that means the clutch is engaged or disengaged). In other words, it's always in a gear no matter what I do with the clutch lever. I've tightened the cable AND loosened the cable with no success. I can see the cable turning the linkage on the transmission, so it seems like it should be working, it just isn't. I'm going to presume that something's broken inside the transmission, but since I'm a novice, can anyone give me an idea where to look or what to look for? I've got a manual on the way (here next week) so that should help, but I want to open it up and take a look at the inside. Searching the interwebs hasn't been of much help. Any help would be enormously appreciated. Thanks in advance!

Did you sort out the problem?

I just bought a 2009 yz450f & have exactly the same problem.

It was working sweet however I up shifted gears with not engaging the clutch & now the clutch won't engage to select any gear.

Any advice would be good.

Thanks

I'm having the same problem with my 04. Taking it apart tomorrow to look at the plates

Perhaps the drive plates are warped.

I have a 2006 450. On my bike if it is not warmed up it lurches forward and dies when I put it in gear. When warmed up it does fine. Feel free to correct me if I am wrong, I was told by the previous owner that they have a hydraulic clutch, so they need to warm up. From one novice to another good luck.

Edited by bluefargo

The bike does not have a hydraulic clutch.  It is, however, a wet clutch, as are almost all motorcycles, so warmup of the oil can contribute, but if the clutch is of an adequate quality, and in good condition, it should not "stick" like that when cold.  It may very well drag a little more than when warm, but the difference should not be so great as that.

I look my clutch cover off, the bolts and springs, and the plates out. This is the first clutch I have inspected but it didn't seam that worn. Or discolored. A couple of the grooves on the plates seamed to be bit worn. The friction plates didnt seam burnt. I put it back in with the sharp side of the separator plates out but the friction plates may be in a different order, is that ok? The plates did seam to be dirty and were sticking together when I took them out, could that have caused my clutch not to engage/ disengage?

Sorry if these are dumb questions. Trying to learn.

https://www.rockymountainatvmc.com/Video/88

 

This video will help. Bought a used 06' model once, same symptoms you describe. Clutch basket fingers were so notched the clutch plates barely moved, if at all.

The clutch basket seamed fine. I ran my finger in there and it seamed fairly smooth. Lol I've probably already watched that video 10 times, as well as a couple more

Got it working. Still drags a ton. But its pretty cold out here in St. Louis. Put the friction plates back in clean and in a different order. I guess that's what did it. Also just installed a fly wheel weight at the same time I inspected my clutch. And the power feels awesome! Thanks TT, great place for info.

Next time you are in there, check the pressure plate for cracks. I had one that developed a crack about a third of the way around it and it was super draggy and stall happy.

I got a new set of plates. Not all of the arms of the friction plates are square. Some have half a hole drilled into the end. Do I have to put those ones in a certain place when installing?

 I realize yours is a YZ but the clutches are REAL similar to the WR ones. I spent pretty much most of last Summer going through my '03 WR clutch repeatedly because of this exact same garbage. I think I went into it 12-13 times and did a big lengthy long term write up on it over in the WR area. It was entitled Clutch Problems. I will try and add a link.

 

 Mine was just about unrideable when I started in on it. If you read through it all (there is a lot!) I even tried changing out to a YZ clutch at one point. The difference between the two is that a WR has one smaller clutch disc with a judder ring that fits inside it, the YZ springs are a little stronger, but the length of the lever down on the motor is a little longer to accommodate the stronger springs. Other than that they are about the same.

 

 Never did figure out why some of them work so good and others are SO bad, but sure am glad I did it.

 

 Go down to post number 126 and you can see pictures of what the final fix was that  I did that cured it big time. What a difference it made.

 

http://www.thumpertalk.com/topic/1100749-clutch-problems/page-7?hl=clutch  issues

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