Drive pulley problem

[Roadster Renovations]

How exactly did you measure? My engine is out right now getting the transmission replace due to repeated sprocket failures. Curious if we can check/adjust as it goes back together.CJ JAX

I made sure that the byke was lifted with the belt in the normal forward position. I then took a flat laser I bought at Office Max ($20) and lay it against the outside of the front sprocket. I then shot the beam back to the rear sprocket and measured how far away from the rear sprocket the red dot was hitting. It was at least 3/8" away from the edge of the rear sprocket. After taking t width off of that, that puts the front sprocket too far out. To verify that I looked at where the belt was ryding on the rear sprocket 2-3 mm's and then where it was on the front sprocket (right against the outing flange edge).

It got me to thinking about this when someone had posted on a thread here about new belt alignment guidelines. They said that the belt could touch one of any of the three flanges (either inner or outer front or inner rear). That did not sound right to me. That is not how my RT belt aligns. Hope that helps.

As someone suggested, perhaps shims to shift the assembly a little farther to the left (as you are sitting on your byke).

If BRP has changed the belt alignment, something is going on IMHO.........

 

[BLUEKNIGHT911]

ENGINE POSITION

Doc do you know or can you see how much the engine can be shifted to get a TRUE alignment ..... Mike :thumbup:

 

[Roadster Renovations]

Doc do you know or can you see how much the engine can be shifted to get a TRUE alignment ..... Mike :thumbup:

Have no idea, Mike. I would think that there has to be some way to adjust it though. I doubt that they would be dumb enough to figure that every frame would be exactly perfect. There has to be an adjustment. What BRP doesn't want to do is have a recall to have all of these F3's out here adjusted. They probably are crossing their fingers and hoping that there aren't that many that will be a problem.
Be interesting if the they would respond to this, like they have the threads about oil filling and checking since they are monitoring all the threads.......

 

[H2O]

Doc,
I think there is a turnbuckle type connection above and forwards of the engine on the RT and would guess that could be used for overall alignment within the frame. I could be wrong. Would also guess the F3 has the same arrangement.

H2O

 

[Roadster Renovations]

I ask a BRP tech about that (name withheld for anonymity) and he said that they are not adjustable.

 

[BLUEKNIGHT911]

ADJUSTMENTS

I ask a BRP tech about that (name withheld for anonymity) and he said that they are not adjustable.

Doc,.... how does this fit with your post # 23 ?????? ........... Mike :thumbup:

 

[Roadster Renovations]

Doc,.... how does this fit with your post # 23 ?????? ........... Mike :thumbup:

Well, it sounds like there is no adjustment. I didn't want to get the tech in trouble for being honest and open with us. I may do a video of the pulley alignment on my F3 just for laughs....

 

[BLUEKNIGHT911]

ENGINE POSITION

Well, it sounds like there is no adjustment. I didn't want to get the tech in trouble for being honest and open with us. I may do a video of the pulley alignment on my F3 just for laughs....

I'm pretty sure I've read on other threads that there is small amount of movability for the engine so it can be perfectly aligned, but I won't bet the farm on this :roflblack::roflblack::roflblack:........ Mike :thumbup:

 

[Wildrice]

I have lowered the on the ground belt tension via Krikit to 130lbs & lots of problems have disappeared. I have no idea of the value checking belt tension with the wheel off the ground, other than the wheel needs to be off the ground to get free motion for adjustment--checking the lb tension while off the ground--can anyone clue me in as to the purpose of the off the ground belt tension measurement ???
Darrell

 

[BLUEKNIGHT911]

BELT TENSION

I have lowered the on the ground belt tension via Krikit to 130lbs & lots of problems have disappeared. I have no idea of the value checking belt tension with the wheel off the ground, other than the wheel needs to be off the ground to get free motion for adjustment--checking the lb tension while off the ground--can anyone clue me in as to the purpose of the off the ground belt tension measurement ???
Darrell

:agree: .. And I also check mine ... ON .... the ground, for a couple of reasons,... when I ride my rear tire is ALWAYS on the ground so checking it that way makes more sense .... because there is a difference in tension settings , and I know what they are , I have made an adjustment to factor this in.... also jacking the Spyder off the ground to check the tension is a pain in the *ss..... jmho .... Mike :thumbup:

 

[jcthorne]

I have lowered the on the ground belt tension via Krikit to 130lbs & lots of problems have disappeared. I have no idea of the value checking belt tension with the wheel off the ground, other than the wheel needs to be off the ground to get free motion for adjustment--checking the lb tension while off the ground--can anyone clue me in as to the purpose of the off the ground belt tension measurement ???
Darrell

Because it provides a consistent measuring point. The length of the extended shock (stock) is a known entity. Measuring with the wheel off the ground give a consistent measuring point on all bikes. Loaded tension is all over the place and indeed will change just bouncing the rear end up and down.

 

[jcthorne]

For most any toothed belt drive, you want to run the lowest belt tension that results in low or no harmonics, no chance of tooth slippage. When BRP issued the tensioner for the F3 they also issued a MUCH lower recommended belt tension, back to what the early RS were running.

I also thought it was interesting that right up to the end of production, the RS V-twins have a harmonic weight on the drive pulley and the 1330 engines do not.

 

[Wildrice]

Because it provides a consistent measuring point. The length of the extended shock (stock) is a known entity. Measuring with the wheel off the ground give a consistent measuring point on all bikes. Loaded tension is all over the place and indeed will change just bouncing the rear end up and down.

Interesting---I do get a (+ or - 10 lb) variation from 120-140 lbs. Just never thought it to be significant or varied via temp or the Krikit, just as tire temp varies without hydrogen air filled tires,