What "gear"?

 

Polaris clutches are balanced as an assembly. You can not mix and match parts without having the clutch balanced again.

 

Also not very well balanced from factory. Contact Dan @indyspecialty. He will balance,replace worn parts and also machine clutch face if needed. Have done a couple clutches with him and noticed how much smoother. Also sometimes has refurbished ones also. Link provided.

 

Sort of hard to believe they can’t unscrew the spider. Warm it up a bit, and a long breaker bar(3’).

 

Was going to say same thing, if dealer can’t get it apart you took it to wrong dealer. Spider is the only part of clutch assembly that can be swapped out between clutches, I still don’t like to but can be done.

 

I have had some spiders gall up and get stuck before. They do require heat sometimes to loosen the Loctite. I'm lucky and can do my own balancing. Most of the P85 clutches I have done have been off about 3 grams. That's equal to about 70 lbs swinging around at 8000 RPM on the end of your crankshaft. They do run noticeably smoother after a precision balance job. Your crank bearings will be much happier also.

 

 

Nice. Lucky you :thumbsup:

 

Definitely a benifit. I made the mandrel. Machining the clutch taper to be exact is no small feat! I can get the balance to less than 100mg.

 

Blueline, Do you have e-start?. I'm just buttoning up both of are sba's, putting e-start on both so I have 2 extra primary's (non e-start). 1 has 450 miles and the other has 950 miles. 1 I plan on keeping for spare, the other one I will sell off.? Minus weights and springs.

 

I believe that the e-start primary sits farther outward on the crank at least 1/8". At least it does on my 2015 with e-start versus my friend's 2017 XCR 800 non-e-start.

The secondary must be shimmed outward for this.

 

Really?. Didn't think of that. Wonder why?. Starter drive throw?. Ring gear clearance?. Don't know why they don't just put treaded holes in all the inner slevee's. like doo ?. Could have just added a ring gear and sent it out for balance. I will have to check this out when I get them back, as a buddy of mine is checking the balance on the new ones at work. thanks..

 

The non estart post much lighter than the e start post even without the ring gear on it. Polaris balancing is not the best. They balance it as an assembly. So somehow they try to detect unbalance on the post sheave and the moveable shave, spider, and cover all at once. Meaning taking out material on the post sheave and cover. This also means that the clutch is "balanced", but because they didnt take out material where the posts heavy side is, or the moveable sheave assembly heavy side is. That heavy side can still exist on each part, still throwing its weight when its spinning. Sometimes they get it right on the money. But not usually. Indy specialty balances the post alone, then the moveable assembly. Makes for a really nice balance.

That other rig in this post is pretty sweet too. :bc:

 

No idea Don? I use it at work. I'm a machinist at an oil refinery. We rebuild pumps, turbines, compressors etc. All the rotating equipment gets balanced in our shop. It's a very nice machine.

 

We had a similar one at a Machine Shop I worked at in the 1960's, last machine shop I worked at didn't have one.

 

It's old for sure. Been updated with new software and gets calibrated annually. 9 times outta 10 it asks to make corrections exactly where the factory balance was. Polaris must have a tolerance of about 3 grams residual unbalance. Most I find are out 3 grams. I can get them down to less than 100mg, which is damn near perfect.

 

@big tom How much? Might need one. Ring gear just exploded one mine this evening. Took out oil line. Stopped right away and called brother for tow home. Haven’t taken it apart yet to assess damage. Engine is good as stopped asap.

 

sno-mo , these are non e-start clutches, no ring gear.

 

Balancing all components individually allows you to change belt to sheave clearance any way you want without affecting the overall balance.

The machine I use, and most reputable shops have similar, is a dynamic balance machine. You tell it where you want to make corrections at and it tells you how much material to remove and where. A dynamic balance corrects all unbalance at once removing or adding material in two planes. This brings the center of gravity to, within a tolerance, in line with the axis of rotation. Which is the definition of balanced.
Component balancing works, but it is laborious. I do all my clutches as an assembly with excellent results. I shim for proper belt to sheave clearance and balance after. I don't need to adjust belt clearance for my riding needs more than once a season.

The shops you want to stay away from are ones using tire balancers. Tire balancers are accurate to about a quarter of an ounce, which is 7grams. Polaris tolerance is 3 grams. Tire balance is designed for tires spinning roughly 500 rpm at 60 mph. I can achieve less than 100mg of unbalance. The clutches i balance are balanced at 1000 rpm mounted to a mandrel roughly the same weight of the crankshaft.
Rember every 100mg of unbalance at 8000 rpm, depending on how far from the centerline, equally roughly 1 pound of centrifugal force. So 3 grams or 3000mg equals 30 lbs swinging around your crankshaft at 8000rpm. Food for thought.

 

Yes I have estart. Thanks anyway.