Drive belt tension.

[Just Doo Me]

What torque should the pulley be?:dontknow:

 

[BajaRon]

And that is (was) the acceptable range when checking, but for adjusting, the specs are even tighter: 1400-1600 Newtons. The rear wheel is supposed to be off the ground to check the tension.

Now this does not make sense to me. With the wheel off the ground the belt tension is at its minimum. As the rear tire moves up into the fender well (to a point) tension increases as the distance from the counter sprocket and rear sprocket increases.

I check mine with the wheel on the gound. To my mind the only way to get an accurate reading is to load the Spyder until the belt is at it's tightest point. Otherwise, you really don't know what your actual maximum tension is.

When running a chain driven system you certainly don't want to adjust the chain anywhere but at maximum tension. It's the only way to get it right.

 

[NancysToy]

Interesting! The 2010 RT shop manual specifies 750 Newtons +/- 250 Newtons (169 lbf +/- 56 lbf) with the rear wheel off the ground. They no longer list separate inspection and adjustment ranges. Are you sure the Service Bulletin said 450 and not 750?

 

[BajaRon]

Interesting! The 2010 RT shop manual specifies 750 Newtons +/- 250 Newtons (169 lbf +/- 56 lbf) with the rear wheel off the ground. They no longer list separate inspection and adjustment ranges. Are you sure the Service Bulletin said 450 and not 750?

Scotty, how do you explain getting the correct tension with the wheel off the ground. I realize that it is all relative and it may be wheel down is an easier baseline to achieve than getting the two sprocket centers horizontal.

But it seems to me that 170lbs with the wheel off the ground could easily be 250lbs (or whatever but certainly significantly higher tension) at apex. So initial tension settings would not be the actual tension during operation.

 

[wyliec]

What torque should the pulley be?:dontknow:

Is this what you are looking for?


http://www.spyderlovers.com/forums/showthread.php?p=195321#post195321

 

[NancysToy]

Scotty, how do you explain getting the correct tension with the wheel off the ground. I realize that it is all relative and it may be wheel down is an easier baseline to achieve than getting the two sprocket centers horizontal.

But it seems to me that 170lbs with the wheel off the ground could easily be 250lbs (or whatever but certainly significantly higher tension) at apex. So initial tension settings would not be the actual tension during operation.

I find that odd, too, but it is really the only way to get something repeatable, since it varies with the load and/or accessories on the Spyder. It is really just a matter of what numbers they use. If the fully raised suspension is the loosest, then that's where they would want to set their minimums (or maximums if the belt was tightest there). Sounds like the number (s) they picked out of the hat were just too high. I have a harder time figuring why they went from 1400-1600 (800-1500 inspection limits) to 500-1000 (750 +/- 250) in the 2010 manual, then cut this even further, along with the allowed variance, to 450 +/- 100 (350 - 550). For those metrically challenged, all readings shown here are in Newtons, per the manual. You would need to convert to pounds-force yourself.

 

[Lamonster]

I just had a tire put on my RT at Burt's and I saw the bulletin and we checked it after the install with my clicker and their sonic meter and mine was at 300 Newtons on their meter and it was about 180lbs on my clicker.

Right now I have the smoothest ride to date, very little belt vibration till I get over 80mph and even then it's only at roll on.

 

[wyliec]

I just had a tire put on my RT at Burt's and I saw the bulletin and we checked it after the install with my clicker and their sonic meter and mine was at 300 Newtons on their meter and it was about 180lbs on my clicker.

Right now I have the smoothest ride to date, very little belt vibration till I get over 80mph and even then it's only at roll on.

Lamonster,

Where did I go wrong?

300 newtons = 67 lbs/force

http://www.onlineconversion.com/force.htm

 

[BajaRon]

I just had a tire put on my RT at Burt's and I saw the bulletin and we checked it after the install with my clicker and their sonic meter and mine was at 300 Newtons on their meter and it was about 180lbs on my clicker.

Right now I have the smoothest ride to date, very little belt vibration till I get over 80mph and even then it's only at roll on.

Like the post above. Something is not right. Did you mean 800 newtons? That would be right at 180lbs.

 

[NancysToy]

Lamonster,

Where did I go wrong?

300 newtons = 67 lbs/force

http://www.onlineconversion.com/force.htm

Like the post above. Something is not right. Did you mean 800 newtons? That would be right at 180lbs.

There is no direct correlation between the sonic gauge measurement and the Kricket, because they use very different methods for the measurement. Best thing with the clicker is to take a measurement after a dealer adjustment, to get a baseline.

 

[garganos]

What torque should the pulley be?:dontknow:

After 6000 miles retorque to 81-89 FT LBS. Mark bolt after torqued. It's a 1 time retorque.

 

[BajaRon]

There is no direct correlation between the sonic gauge measurement and the Kricket, because they use very different methods for the measurement. Best thing with the clicker is to take a measurement after a dealer adjustment, to get a baseline.

I'll grant that the Kirkit may not give the same reading as the gauge used by the dealership, but do you think Lamont's actual tension (by the dealers newton gauge) is 67 lbs?)

 

[BajaRon]

I find that odd, too, but it is really the only way to get something repeatable, since it varies with the load and/or accessories on the Spyder. It is really just a matter of what numbers they use. If the fully raised suspension is the loosest, then that's where they would want to set their minimums (or maximums if the belt was tightest there). Sounds like the number (s) they picked out of the hat were just too high. I have a harder time figuring why they went from 1400-1600 (800-1500 inspection limits) to 500-1000 (750 +/- 250) in the 2010 manual, then cut this even further, along with the allowed variance, to 450 +/- 100 (350 - 550). For those metrically challenged, all readings shown here are in Newtons, per the manual. You would need to convert to pounds-force yourself.

Agreed that getting a repeatable tension (and universal tension position of components) is important and makes sense that wheel off the ground would give you that. All that would have to be done by the engineers is attain the correct apex tension, lift the wheel off the groung, measure tension at the wheel down position and spec. to that number.

Was the original tension spec. also at the wheel down position or was it at apex?

I also agree that their original numbers had an unnervingly wide range, not to mention a tension higher than would seem reasonable. Almost seems like they are pulling numbers out of their hat, though I feel a lot better about these latest specs. for what that's worth.

 

[NancysToy]

I'll grant that the Kirkit may not give the same reading as the gauge used by the dealership, but do you think Lamont's actual tension (by the dealers newton gauge) is 67 lbs?)

I would be surprised at that. When Nancy's GS was just adjusted at the dealer, my Krikit was maxed out, as expected. I lowered it to a reading of near 240, similar to what Lamont was running then. Still seemed tight, so I backed it down some more until the belt sounded better. Still remained above 200 when not jacked up. I can't believe that I would be approaching a tension 1/4 of the original.....or that Lamont would be. My suspicion is more that the sonic gauge is less reliable at low tensions? :dontknow:

Agreed that getting a repeatable tension (and universal tension position of components) is important and makes sense that wheel off the ground would give you that. All that would have to be done by the engineers is attain the correct apex tension, lift the wheel off the ground, measure tension at the wheel down position and spec. to that number.

Was the original tension spec. also at the wheel down position or was it at apex?

I also agree that their original numbers had an unnervingly wide range, not to mention a tension higher than would seem reasonable. Almost seems like they are pulling numbers out of their hat, though I feel a lot better about these latest specs. for what that's worth.

The book adjustment procedure specifies wheel off the ground, with suspension extended. Their inspection numbers do not specify that however. Lots of inconsistencies here. I guess the important thing is to recognize that BRP has seen the problems that have developed from excessive belt tension, have researched what was happening in the real world, and have adjusted their specification. If there was no science in the numbers before, there is at least some method to their madness now.

 

[BajaRon]

I would be surprised at that. When Nancy's GS was just adjusted at the dealer, my Krikit was maxed out, as expected. I lowered it to a reading of near 240, similar to what Lamont was running then. Still seemed tight, so I backed it down some more until the belt sounded better. Still remained above 200 when not jacked up. I can't believe that I would be approaching a tension 1/4 of the original.....or that Lamont would be. My suspicion is more that the sonic gauge is less reliable at low tensions? :dontknow:


The book adjustment procedure specifies wheel off the ground, with suspension extended. Their inspection numbers do not specify that however. Lots of inconsistencies here. I guess the important thing is to recognize that BRP has seen the problems that have developed from excessive belt tension, have researched what was happening in the real world, and have adjusted their specification. If there was no science in the numbers before, there is at least some method to their madness now.

I would think there was some science in BRP's original numbers. But sometimes there can be a disconnect between science and reality. There had to be some kind of miscommunication there somewhere.

But whatever the original issue I agree that the numbers look much better now and you're right. Going in the proper direction is a good thing.

I am not familiar with the sonic gauges but I would suspect that a certain minimum tension would be required to get an accurate reading. Newtons mean nothing to me until converted to pounds. But I'd say there is no way the belt is going to work with 67lbs tension.

Lamont's 180lbs on his Krikit sounds a lot better to me. I believe we were running between 200 and 250lbs with the rear wheel on the ground. Granted, you're not going to get a consistant measurement this way, hence the lifted wheel instructions.

I am definitely going to take another look at mine.

 

[Lamonster]

Like the post above. Something is not right. Did you mean 800 newtons? That would be right at 180lbs.

I may have got my newton number wrong,:dontknow:pps: I was going from memory. I do know my clicker read 180lbs because I normally have it around 220lbs.

 

[BajaRon]

I may have got my newton number wrong,:dontknow:pps: I was going from memory. I do know my clicker read 180lbs because I normally have it around 220lbs.

Lamonster get something wrong?!! Say it ain't so!

Glad to hear you're still out there somewhere. How are the fruits & nuts these days?

 

[Lamonster]

Lamonster get something wrong?!! Say it ain't so!

Glad to hear you're still out there somewhere. How are the fruits & nuts these days?

 

[LittleJohn]

Like the post above. Something is not right. Did you mean 800 newtons? That would be right at 180lbs.

Whew!!!! I don't think even I could put away 800 Newtons....(snicker)

 

[ISCI Billy]

When i was at the BRP event in Daytona . A BRP tech. was checking everyones belt tension . Mine was at 280 and some where as high as 1500. I thought that the spread was huge but the tech said they where all in spec .:dontknow:

We had our 2010 RT checked as well. We were having some minor issues at the time and our belt was so lose it would not give a reading. They did fix it for us on site. That was nice.