Ok history. 750 miles on original belt. I decided to reshim my belt yesterday. Before shimming I had nearly 1 1/4" of deflection. Took out both shims. They weren't marked and both were thick. 1.?mm. Now the belt rides about a 1/16th of an inch out of the driven pulley and deflection is down to about 13/16". It doesn't squeal in gear so I doubt it is too tight. It will chirp when first shifting into gear but quits right away. I do not like the way it runs now!!!! I cannot even feel the engagement anymore and it feels like the motor is being forced to pull the ATV from idle on up which has killed the holeshot. I lost about 7mph on the top end too. Which brings me to my questions.
Secondary spring? A stiffer spring will create the exact same thing I am experiencing now so why run it? Wouldn't you want a slightly looser spring in the driven clutch.
Primary springs and weights? It seems that a person would get the most tuning abilty from what is going on in the primary and the secondary should be mostly left alone.
If I seem a bit confused it is because I am! Having never dealt with sleds or anything else that runs this type clutch system I have a lot to learn.
Sideload?
backshift?
controlling engagement?
I can't find a resource on the net that really explains how these things work.
Is there a CVT clutches for dummies?

BTW, thanks NYROC for the info on your website it was a great help. I built a hinged spanner out of 3/16 X 1" bar to hold the secondary clutch while loosening the bolt but the bolt was so tight that I ended up buying an impact to remove it. When a two foot cheater began to cause the floor board that I had the spanner wedged against to bend I figured I better quit. It did work great for retorquing the bolt.
Instead of a 2" pipe cap for the compression tool I used a 2 X 1/2" bell reducer. Saved drilling a hole in it.

 

The tight belt will be a longer lasting belt. But a tight belt will also take some top speed from you. By taking shims out, the belt can't get into as small a radius on the secondary clutch as a belt on a shimmed clutch. The sheaves are further apart on a shimmed secondary clutch and let the belt go further into the sheaves, resulting in a higher gear ratio. So it is a trade off in adjusting the belt. You can go to max top speed or max belt life. I'll go for max belt life, because I rarely hit top speed on mine. I would rather have acceleration and I don't want to wear my belt out always punching the throttle. But everyone has differnet riding habits and wants different things. I'm not sure about your loss of holeshot. I would assume that with a tighter belt, you would get a better hole shot because there would be less slippage.

 

Clutch Tuning Book

 

spec's for deflection is .87 to 1.06,

rule of thumb, every .1mm change in shim equals, .05" change in deflection, you took out both shims so now you have decreased your deflection by more than 1 inch, which is too much.

You need to put one back in, that should give get you back to near normal.

Don't get worried about clutching, if you don't understand it just bump along with what others are saying works well.

black spring in driven and red in primary works well for most people. Clutch weights will come more to the for front as the CDI comes out.

PM me if I can ever help!

 

Ummm.... I think you may be overlooking something here...

This may be a shot in the dark, but have you checked to make sure you put the belt back on the right way?

The arrows should be pointing towards the front of the 650. If they aren't, this would cause the problems you're experiencing.

Something you might want to check out.

 

Nemmeh, that's a good thing to check.

I've seen people put them on backwards. Every time I read a belt squeeling post, I would post "is your belt on backwards". I have never even got a commit on it, so I thought we must be the only ones to have done it.

later

 

Is the belt tension made to be adjustable, or is taking shims out just causing misalligned pulleys, therefore increasing belt tension? If so, would the belt not wear faster?

RebelDS,
I do not understand the cvt, but with a new belt installed, my top speed increased 2 mph. It squealed for the first 10-12 hours of use, so I can assume it was much tighter than the worn belt.

 

Ok. Much better now. I was sure I had put the belt back on right but I wanted to look again anyway. What I found was the belt was on the right direction but it was now riding 1/4" out of the rear shieve. Checked deflection and it was only 3/8" of an inch. You want to talk about a mother try removing a belt that is on that tight! I guess in my haste last night I hadn't rolled the belt enough to get the shieve halves all the way back together. I reinstalled one shim and it now checks at exactly 1". Engagement has gone back up to about 1600rpm and top end is almost where it was before. It's a good thing I looked again because I had also installed the two cone washers on backwards under the nut.
Thanks again!!

 

Rutwad, the adjustments you make for the belt are in the service manual. It's a standard adjustment approved and recommended by Kawasaki. The specs you see, from 0.87" to 1.06" is the spec recommended by Kawasaki, and I'm not sure why they sell them out of spec. But the shims are also regular Kawasaki parts. So this is something you should do, and not some crazy idea where someone is putting your pulleys out of line.

To think of a CVT, think a 10 speed bicycle or a mountain bike. As you accelerate, the drive clutch (front pulley) squeezes together and the radius increases, like a bicycle with the chain jumping to a larger sprocket. When the front pulley squeezes together, the driven clutch (back pulley) allows the belt to rid further into the sheaves, like the bicycle with the chain dropping down to the smaller sprockets.

On the driven clutch, the shims give more space between the sheaves, allowing the belt to fit deeper into the clutch, or pulley. As you are going faster, the sheaves on the clutch pull apart allowing the belt to rotate deeper with shims than without shims. If you compare that to a bicycle, with shims, it's like running at the next to the smallest sprocket and without shims, it's like running on the smallest sprocket. Basically, as the clutch sheaves move in and out from each other, you are changing the gear ratio by changing the radius of the belt circling the clutch.

Those aftermarket springs, weights, etc. you see being sold for the clutches basically cause how much the clutches sheaves move in and out, in relation to how fast the it spins. An engineering degree comes in handy sometimes [img]i/expressions/face-icon-small-smile.gif[/img]

 

OK, got it........sort of.
With no noticeable problems, would you check the belt?