Hello.

I have been trying to figure out how to adjust the belt deflection/belt height in the secondary for a while now.

When I ask about it, most people say "adjust so your belt rides just above the secondary". The only place I see this in my Ski-Doo Race Manual, Shop manual, Specification Books, or anything else, it says 0-1/16 inches, FOR REFERENCE ONLY.

The manual says nothing about belt height when adjusting, just to adjust my secondary so that my belt has 1.25 inches of deflection with 25 lbs of force applied. I do this using a straight edge, fish scale, and a couple long 3/8" drive ratchet extensions. I marked 1.25" up from the bottom of the ratchet, and then apply 25 lbs on the scale, and see where the line is in relation to the bottom of the straight edge. Then adjust the three allen screws/nuts equally to give me more or less deflection. I have also noticed that this 1.25"/25 lbs corresponds to the track just creeping at idle while the track is up in the air.

I am going to use a Ski-Doo 067 Belt this year, and it seems a little shorter than the Gates Extreme that I used last year (I have always had someone else do the adjustment before). The gates would run higher in the secondary than the 067 that I have only run for a few miles so far.

Am I going to lose any performance from the belt not getting high enough in the secondary?? Does it even matter?? Why then does everyone say that it should ride above the secondary??

Is there a way to make a shorter belt ride up in the secondary??

I know my center-to-center distance, offset, "X", "Y", "Z" are all within spec. I have the Ski-Doo alignment bar & digital calipers to check distances, all of them are dead nuts on with the Manual.

If I am going to do a bunch of drag races, should I run the belt deflection tighter? I have heard that drag racers commonly do this.

Anyone??

Thanks,

Jim
1997 Ski-Doo Mach 1

running to short will take away from top end. the best way is to adjust it like the book says and then put a mark on the clutch faces with a black marker from the top to the bottom on the drive and driven and run it and see what wipes off and adjust from there

How would that take away from top end? At top speed w/ clutches shifted fully out, the belt will be riding HIGH in the primary clutch, and then LOW in the secondary. The only time the belt rides high is at very low speeds. I did a little re-gearing, so it pulls out of the hole like a raped ape.

I will mark the clutches before riding today and see what it tells me.

Thanks,

Jim

Never mind the belt deflection measuring thing! Just simply hang your sled so the track doesn't touch the floor. loosen all three belt adjusting screws. Start sled and screw in one screw only until your track is just barely spinning, if it wont idle then you may have to screw in a little more. Once you have done this simply screw in the other two screws until they lightly seat, this way a three are adjusted the same. Tighten the lock nuts being carefull the set screw doesn't turn with it and your done...

The manual says nothing about belt height when adjusting, just to adjust my secondary so that my belt has 1.25 inches of deflection with 25 lbs of force applied. I do this using a straight edge, fish scale, and a couple long 3/8" drive ratchet extensions. I marked 1.25" up from the bottom of the ratchet, and then apply 25 lbs on the scale, and see where the line is in relation to the bottom of the straight edge. Then adjust the three allen screws/nuts equally to give me more or less deflection. I have also noticed that this 1.25"/25 lbs corresponds to the track just creeping at idle while the track is up in the air.[COLOR=red]



Do just what the manual says. The belt height in the secondary is a result of having the proper belt deflection. That is why they say "reference only". Usualy with a 1 1/4" deflection, the ride height in the secondary is about 1/16".

If the track creeps when lifted off the ground, is a good sign that belt is adjusted right.

Originally posted by Mikadoo@Dec 18 2003, 07:27 PM
Never mind the belt deflection measuring thing! Just simply hang your sled so the track doesn't touch the floor. loosen all three belt adjusting screws. Start sled and screw in one screw only until your track is just barely spinning, if it wont idle then you may have to screw in a little more. Once you have done this simply screw in the other two screws until they lightly seat, this way a three are adjusted the same. Tighten the lock nuts being carefull the set screw doesn't turn with it and your done...
I concur... :)

Sled is on track stand. Start the sled. Warm the engine up. Burp the
engine to turn the track. Get the track nice and limber. Get the "cold"
out of the track and loosen it up.
When the sled is on a track stand and the engine started and idling; The
track should 1]Creep slowly or 2]Turn with jerking movements or 3] Track is
still, but you are able to move it with by pinching it with index finger and
thumb, then pulling it around fairly easy.

I have measure belts that were 3/8" shorter than spec, and up to 5/8 longer than spec. There are some belts that are a disaster.
This way here, regardless of belt length [within reasonable amount] performing belt deflection procedure like Mikadoo mentions will make for consistant clutching.

I think that's the best way to do it too!

The only time I've had to re-do it was if the track was too cold (even in a heated shop). As Joe mentioned, make sure that the belt and track are up to operating temp (if there is such a thing).

Hmm....not really operating temperature so to speak. heh heh...

Say if I do this on a fresh cold sled, you know when you start a cold sled, all the smoke that happens?...I like to run the sled long enough turning the track so the engine warms up and smoking goes away. Takes a few minutes, but by that time the track is more supple so there is no creases in the rubber from sitting. :)

I`ve always gone by the manual as well, and other than caibration issues have never had any adverse effects on the belts. Does it matter if the belt is over the driven? NO. The old thought process to that is to have more ratio for launch. Think about how long in feet you`re in the starting ratio of the CVT. How about 1 foot give or take a 1/2. Does anyone on this thread think 1/16 of an inch gives them better ET? Doubt it. If deflection is correct for the belt being used I believe you`re in good shape. The creeping track thing is a good way to know it`s all on track. Too tight the sled won`t idle, too loose it won`t shift out to it`s calibrated ratio. I`ll bet it`s a cat or yammie guy saying the over the edge thing.

i believe the over the clutch height is for the rer clutch as it is smaller in diameter