Belt Tension and Vibration

[Jeriatric]

Hey Jim,

Hate to hear about your fall. Seeing stars instead of fireworks.....that was a good one

Hope your recovery goes well. :thumbup:

Jer

 

[phj]

Yes, I remember your call, I was sitting in the emergency with my arm in a sling with a shoulder injury. Busted my *** after I stepped in some iguana crap on the sidewalk while waiting for the fireworks to start, we have a lot of iguana's in S. FL.. Seen some stars that night but not much fireworks, was sitting on the couch at 8:30 using a bag of frozen cut green beans for an ice pack.
You wouldn't be the first to change back to 2 wheels over belt vibration I think, I've had many customers tell me they would have dumped it long ago if they couldn't get rid of the vibration. Unfortunately, the tensioner is not a cure-all for everyone, for many it is, but I suspect many are running a tighter tension than the book calls for, and some, maybe most don't seem to have any vibration for some reason. Many mechanics are thorough and will check, adjust and grease everything by the book, well, everything except the grease fittings on the top back A-arms, which require near complete dis-assembly to change, and others, not so much, as in "Hey, I got a lot of bikes in front of me, and if it ain't broke, don't fix it. The belt is 40" long between sprocket centers and the belt tends to want to follow the curvature of the front sprocket as the teeth from the belt separate from the sprocket teeth, throwing a ripple effect towards the back sprocket. The belt doesn't know or care what gear your in, it is more speed related. Until BRP raises the tension back the other way some or comes out with something better in the way of belt control or a tensioning system some are still going to have some vibration, even with the tensioner, although greatly reduced I hope. In addition to that there is still some belt squeal and noise, hence the gray coating on the new belts. I like my tensioner business, but I love the joy from knowing I made a positive difference in another spyder riders time in the saddle. Sometimes though I feel like I am one little person trying to fix all of BRP's belt woes. Riders call or email me day and night because they can't get thru to BRP or are referred back to the dealer whose hands are tied. Why can't they fix my squealing belt!, or they adjusted it and now it's off to one side!,or what is that growling noise?, or the vibration is driving me crazy and I shouldn't have to buy a tensioner after I just spent 25k.
I'm happy to share my limited knowledge or give what advice I can, but I don't work for BRP, and I don't have all the answers. I love my GS dearly and I think BRP has done a great job bringing us something exciting and new to the market, a new paradigm they call it, and I'm not here to bash them and certainly want them to prosper and bring us new things, but bad news travels fast, and they need to start addressing and ironing out some of these design defects instead of flooding the market with new spyders with old problems. They fixed the steering problem, which was a biggie as far as a liability issue, but the fly by wire throttle and related electrical problems seem to be causing a lot of grief, and the dreaded limp mode while on a busy highway is downright frightening. As far as lowering the belt tension 3 times and the vibration that may ensue, the customer and dealers should not have to endure the frustration and misery for BRP's drivetrain engineering, or lack there of, and miscalculation of what damage might occur from a belt that long set tight enough to not vibrate, many of their customers will suffer needlessly or have to spend more money on a tensioner because BRP may have to replace some bearings at their cost while under warranty. BRP at least should give the dealers and mechanics some leeway to use their own judgement, discretion and experience when setting the belt tension since it was BRP's doing, raise it up a little at a time if necessary until the customer is happy, if there is still a little vibration we will buy them a tensioner, which should clean up what's left. It maybe a little tighter than BRP likes and they may have to replace a few bearings here and there, but look at all the money they have saved by not redesigning anything or adding a tensioner of some sort. The customer is king, and a happy customer will come back and pass on the good word and bring more sales, people tend to remember the bad stuff they hear long after they have forgotten the good things.
And most customers bought a smooth running spyder when new I would imagine, as most complaints come after the belt is readjusted, it's not fair to change the rules in the middle of the game. I went to visit my folks in Central FL. a couple of weeks ago and stopped in a large dealership, they had 4 new RT's and 2 used ones, one with 3500 miles and one with 9500, no RS's. The first thing I do naturally is reach in and feel the tension, the new ones were very tight and the used ones were very loose. Had they been RS's I would have thought nothing of it, as they are traded for RT's frequently, but the first thing to cross my mind is they probably couldn't stand the vibration and traded it in, it made me sad.

Capt. Jim,

Very well said and I do hope we/I can figure this all out for I do enjoy riding this bike.

When I arrived at my place in the North Country last week, I found the tensioner had loosened and I was at ten #'s. So we did gain by going from 7# to 10# but still not where we need to get. On the way home today I set the tensioner at 14# and at times it seemed better yet, but then there were periods where though improved, still not smooth. It was about a 150 mile ride and I tried many different speeds as well as gears/speeds and that has no difference at all. In fact it seems to vibrate more when at higher speeds and still in a lower gear. I did find that being in 5TH gear at a lower speed (52mph) was in-fact the smoothest. It is just funny how the vibration can come and go, sometimes by slowing will remove it and then times by speeding up will help. The only constant at this time is speeds below 55mph in 4TH or 5Th gear are now smooth.

Capt Jim, what is the max I can bring the tensioner up to? I believe they have the belt set about 600 at this time. I know I can go back and have them bring it up (belt tension) some more, but can I also do the same with the tensioner?

I believe we are making headway and your tensioner does help a lot, just need to get it fine tuned for this bike. I am also open to any suggestions you may have. I will try and give you a call in the AM tomorrow.

Paul

 

[capt.jim]

Hey Jim,

Hate to hear about your fall. Seeing stars instead of fireworks.....that was a good one

Hope your recovery goes well. :thumbup:

Jer

Thanks, actually, it is feeling somewhat better, and I've already started therapy on my own before my Appt. with the orthopedic surgeon on Tues., I went for a short ride today!

 

[capt.jim]

Capt. Jim,

Very well said and I do hope we/I can figure this all out for I do enjoy riding this bike.

When I arrived at my place in the North Country last week, I found the tensioner had loosened and I was at ten #'s. So we did gain by going from 7# to 10# but still not where we need to get. On the way home today I set the tensioner at 14# and at times it seemed better yet, but then there were periods where though improved, still not smooth. It was about a 150 mile ride and I tried many different speeds as well as gears/speeds and that has no difference at all. In fact it seems to vibrate more when at higher speeds and still in a lower gear. I did find that being in 5TH gear at a lower speed (52mph) was in-fact the smoothest. It is just funny how the vibration can come and go, sometimes by slowing will remove it and then times by speeding up will help. The only constant at this time is speeds below 55mph in 4TH or 5Th gear are now smooth.

Capt Jim, what is the max I can bring the tensioner up to? I believe they have the belt set about 600 at this time. I know I can go back and have them bring it up (belt tension) some more, but can I also do the same with the tensioner?

I believe we are making headway and your tensioner does help a lot, just need to get it fine tuned for this bike. I am also open to any suggestions you may have. I will try and give you a call in the AM tomorrow.

Paul

That particular model is good from 10-16lbs. and normally 10 lbs. works on most. From a moral liability standpoint I don't want to be the one to tell you to crank it up any more than necessary to add additional Lbs. to the static tension you already have, even though at a low 600 newtons the additional tension is minimal and spring tension at that.
Your dealer is your dealer and he's going by the book, and I have to respect that, even though he may not be helping your vibration problem. I don't like to second guess them, go above them or step on anyone's toes. My product is going on your baby and I want to help you fix the problem as conservatively and gingerly as possible without being too invasive, I'm sure the dealer feels the same about his service.

But if it was mine I would have no problem about setting it at 14-15 just to see, it will go a little more but I don't like to max anything out, I'd give it a little breathing room, anymore than 16 lbs. and it turns into a fixed tensioner with no spring left. It would be the easiest thing to do in a few minutes. The next model up is identical but rated at 20-26 Lbs., but I've never felt a need to think of that one. Yet.

 

[Ga Blue Knight]

Some say that my rpms match my I.Q. :shocked: :roflblack:

Now you're making my brain vibrate!

 

[Rotaxer]

Capt. Jim,

Very well said and I do hope we/I can figure this all out for I do enjoy riding this bike.

When I arrived at my place in the North Country last week, I found the tensioner had loosened and I was at ten #'s. So we did gain by going from 7# to 10# but still not where we need to get. On the way home today I set the tensioner at 14# and at times it seemed better yet, but then there were periods where though improved, still not smooth. It was about a 150 mile ride and I tried many different speeds as well as gears/speeds and that has no difference at all. In fact it seems to vibrate more when at higher speeds and still in a lower gear. I did find that being in 5TH gear at a lower speed (52mph) was in-fact the smoothest. It is just funny how the vibration can come and go, sometimes by slowing will remove it and then times by speeding up will help. The only constant at this time is speeds below 55mph in 4TH or 5Th gear are now smooth.

Capt Jim, what is the max I can bring the tensioner up to? I believe they have the belt set about 600 at this time. I know I can go back and have them bring it up (belt tension) some more, but can I also do the same with the tensioner?

I believe we are making headway and your tensioner does help a lot, just need to get it fine tuned for this bike. I am also open to any suggestions you may have. I will try and give you a call in the AM tomorrow.

Paul

Any chance that the rear wheel lost a weight, maybe the belt isn't the only thing causing a vibration. Maybe have the dealer check the balance.

 

[phj]

Any chance that the rear wheel lost a weight, maybe the belt isn't the only thing causing a vibration. Maybe have the dealer check the balance.

When I had my dealer install the tensioner I also paid to have them check the balance on all three wheels......a $225.00 expense and have been told they are all balanced.

 

[Rotaxer]

When I had my dealer install the tensioner I also paid to have them check the balance on all three wheels......a $225.00 expense and have been told they are all balanced.

Ouch!!!!! What is the cost of a new belt? Maybe the belt is the problem or maybe the new coated one runs smoother. I feel for you paying that much money to have this much grief. Also has made me hesitant to buy one, just because I have that kind of luck!!

 

[Rayelljay]

I've worked with belt drives and idler systems for a number of years and I've seen perfectly adjusted systems do horrible things to idler tensioning systems.
One of the problems is that you can pre-load the idler to deflect the belt statically but once the drive is running the "slack" side of the belt leaves the idler behind. When one side of the pulley is exerting force enough to stretch the belt, the other side becomes loose enough so that the belt will rarely touch the idler.
It's not a question of how much pre-tension is introduced into the system by the idler, but the resistance of the idler to be deflected by the belt vibrations.
It comes down to the choice of spring rate in the idler system. the length of the lever arm and the weight of the idler itself. A light idler will be easier deflected than a heavier one......too light of a spring rate will cause the idler and it's lever arm to flutter even against the spring.
If some means could be found to dampen those extraordinary belt excursions.........
Has anyone actually seen with their own eyes just what happens with a Spyder drive belt under load...??...Just look at your belt guard and see the marks.
Let me be absolutely clear here: I am in no way trying to malign the work already done by our SpyderLover sponsor in his business....I'm just trying to evoke further comments and suggestions.

 

[Jeriatric]

I've worked with belt drives and idler systems for a number of years and I've seen perfectly adjusted systems do horrible things to idler tensioning systems.
One of the problems is that you can pre-load the idler to deflect the belt statically but once the drive is running the "slack" side of the belt leaves the idler behind. When one side of the pulley is exerting force enough to stretch the belt, the other side becomes loose enough so that the belt will rarely touch the idler.
It's not a question of how much pre-tension is introduced into the system by the idler, but the resistance of the idler to be deflected by the belt vibrations.
It comes down to the choice of spring rate in the idler system. the length of the lever arm and the weight of the idler itself. A light idler will be easier deflected than a heavier one......too light of a spring rate will cause the idler and it's lever arm to flutter even against the spring.
If some means could be found to dampen those extraordinary belt excursions.........
Has anyone actually seen with their own eyes just what happens with a Spyder drive belt under load...??...Just look at your belt guard and see the marks.
Let me be absolutely clear here: I am in no way trying to malign the work already done by our SpyderLover sponsor in his business....I'm just trying to evoke further comments and suggestions.

Ray, suppose I should ask if you use the Smoothspyder tensioner?

Here's my input, understand I'm no expert here. Installed the unit myself and based on what I have observed(in both seat of the pants input at high speed, and at lower speeds listening to noise inputs). I think it meets all the requirements you set forth. That said, unless or until someone mounts a camera on their Spyder to give real world visual feedback that's about all we have to rely on. So far, and it has been on long enough in my case. I think it works.

 

[phj]

I've worked with belt drives and idler systems for a number of years and I've seen perfectly adjusted systems do horrible things to idler tensioning systems.
One of the problems is that you can pre-load the idler to deflect the belt statically but once the drive is running the "slack" side of the belt leaves the idler behind. When one side of the pulley is exerting force enough to stretch the belt, the other side becomes loose enough so that the belt will rarely touch the idler.
It's not a question of how much pre-tension is introduced into the system by the idler, but the resistance of the idler to be deflected by the belt vibrations.
It comes down to the choice of spring rate in the idler system. the length of the lever arm and the weight of the idler itself. A light idler will be easier deflected than a heavier one......too light of a spring rate will cause the idler and it's lever arm to flutter even against the spring.
If some means could be found to dampen those extraordinary belt excursions.........
Has anyone actually seen with their own eyes just what happens with a Spyder drive belt under load...??...Just look at your belt guard and see the marks.
Let me be absolutely clear here: I am in no way trying to malign the work already done by our SpyderLover sponsor in his business....I'm just trying to evoke further comments and suggestions.

I my case it (tensioner) has helped a lot but not completely curred the problem. I have tried every rpm/shifting combination and at higher speeds it just does not go away, lower speeds, less than 55mph any gear at any rpm it's smooth as silk. In my opinion the belt is just to loose and I am trying to get my dealer to go back to 750/800 newtons. They are reluctant because of BRP. I firmly believe that if the riders that are reporting no vibration checked their belts they would be much tighter than the 400 +/- 150 being called for by BRP

 

[Jeriatric]

I my case it (tensioner) has helped a lot but not completely curred the problem. I have tried every rpm/shifting combination and at higher speeds it just does not go away, lower speeds, less than 55mph any gear at any rpm it's smooth as silk. In my opinion the belt is just to loose and I am trying to get my dealer to go back to 750/800 newtons. They are reluctant because of BRP. I firmly believe that if the riders that are reporting no vibration checked their belts they would be much tighter than the 400 +/- 150 being called for by BRP

Higher speeds?

How high, and what RPM.

 

[Fire Bike]

vibes too

I noticed some vibes on my new 2012 RTS but thought it may be normal after 30+ years on Goldwings.

 

[phj]

Hey Capt. Jim,

It was nice chatting with you again today. I had a great ride north today and did a lot more checking and what I found was that about 4550 rpms or 62/63 mph is where the vibrations now began (so it's getting better). If I am accelerating up in speed, the vibration continues and will not go away; however, if I accelerate to a higher speed and then slow to that 4550 rpms, there is no vibration and will run smooth until I start increasing rpms again. So, I believe we are very close and I look forward to the response you get from your engineers and maybe we can solve this once and for all.

As we also discussed, I did some high rpm shifting and it actually makes it vibrate more. But whether I'm in fourth or fifth gear at any rpm up to 61mph and 4500 rpms it is now smooth as silk and for other than road bumps you wouldn't even know the bike/engine was running. I also agree that some of what I may be feeling at the higher rpms may be coming from the engine for at the higher rpms you can feel the engine more, but I still have some belt vibration in there as well. If BRP would allow my dealer to reset the belt to 700 newtons I am sure that would along with your tensioner solve all the vibrations, at least on this bike.

Thanks again for all your advice and help, you are a true professional and build/sell a great product.

Paul

 

[summerdawn]

This is an interesting thread. I just returned from my first extended trip that included a lot of time at interstate speeds 65 to 75 mph. I found that as I reached about 73 mph (occasionally 71) there was a vibration/rubbing sensation in the bike. Going slower or faster got rid of it but it would come back at that speed. I was in 5th gear. Lower speeds are all smooth. After reading the thread I'm worried that if I ask the dealer to look at/adjust the belt I might wind up with more vibration.