I’m getting frustrated with the belt vibration - any ideas to help?

[BLUEKNIGHT911]

Could be belt vibration. Some add a dampener.

Dampers have ruined many drive belts since their introduction. Option B is to LOWER the Belt tension down to around 160 lbs. using a KritKit tester - I use this when the tire is on the ground, and after 80,000 miles, my belt still looks great and is quiet ..... Mike :thumbup:

 

[RayBJ]

Damper will likely solve the vibration, Careful monitoring of the roller should prevent belt damage. I change the roller every 15k miles because they do wear. On #3 with no issues.

 

[Mikey]

:agree: If you have to drink the Kool-Aid, Monitor your bearings in the darn thing!!

 

[Poppie65]

During our ride from Greenville, TN to Piney Flats, TN a couple of weeks ago after the tires had been replaced by the guys at BajaRon’s shop, we experienced an unexpected vibration while climbing a hill at 72 mph. It wasn’t coming from the tires or suspension, but instead felt like the drive belt and was felt in the footrests and seat, not in the handlebars. It didn’t stop until we slowed down and then didn’t reappear until much later in the day under similar circumstances. We changed our plans for the next day and drove back down to Greenville to see the guys at the shop and try to figure it out.

We pulled in and met Daniel for the first time and I described the problem to him. He took the bike it for a ride and when he returned, he checked the belt tension and adjusted it from 200 to 230 lbs. My wife and I test rode again and confirmed the problem was still present. Back at the shop Daniel hopped on with me and we took another ride, paying attention to gear and rpm. We were testing on a local rural road, maybe 5 miles from the shop. It had curves and hills that helped to duplicate the conditions where we first experienced the vibration. From a stop at the bottom of a rather long hill (not sure of the grade), I worked through the gears at near full throttle with the goal of getting up to 70 mph before we got to the top. The bike rode smoothly through all the gear shifts until we went into 6th gear. I don’t recall the speed, low to mid 60’s maybe, but the rpm’s were at 3100 to 3200.

Daniel asked if he could check the belt damper, and when he pulled it off, we found a slight amount of play in the roller. He replaced it with a new one then test rode again but found the problem still present. All gears smooth until switching to 6th while climbing a hill at 3200(ish) rpms.

Back at the shop again, he checked the rear sprocket grommets and found them to be present and in good shape. Daniel was very focused on the problem, and he worked hard on a resolution. At one point he offered to change the rear tire again to a size slightly smaller than what was installed, but I declined. We left the shop with the feeling that the vibration was a result of lugging the engine while riding two-up and fully loaded.

While Daniel was working on our bike, my wife and I had opportunity to meet and talk to Ron. He’s obviously very knowledgeable but also a very pleasant man who we enjoyed talking with. We complemented him on his crew and their interaction with their customers. Working with Adrian, Paige, and Daniel was an absolute pleasure. Can’t speak highly enough of them all.

While riding after leaving Greenville, I was able to isolate when the vibration occurs. I’m feeling confident that it is coming from the drive belt.
With us riding 2-up, and the storage compartments loaded up full, the vibration occurred between 3200 & 3500 rpm, regardless of what gear we were in and if enough throttle load is applied. When 3600 rpm is reached, the vibration stops immediately. It is also felt when cruising at 3600 or higher and a dip in the road surface is encountered that causes the suspension to compress.

When we got home and unloaded everything we rode back into town and found that vibration did not occur as easily.

This past weekend she and I took a ride on Sunday into SE Indiana and found some nice open and hilly country roads. I was cruising around 55 mph, in 5th gear and 3200 rpm. On a level surface, everything is smooth as silk. As we crested the hills, I found that when the bike felt a “negative G” the vibration reappeared for an instant. Same thing when we rode over a dip in the road. These would be attributed to very quick changes in belt tension if I’m correct. I also reconfirmed the same rpm and throttle load conditions that were mentioned above.

While riding around last weekend and making mental notes for this post, I got the impression that we’ve felt the vibration when the OEM tires were still installed, but maybe just once or twice, and they were just as brief as I described when rolling through a dip in the road.

So, my impression is that the vibration is coming from the drive belt, and it has just recently appeared because the new rear tire (Altimax RT45, 215/60 R15) is larger than what was removed (OEM Kenda), which lowered the RPM range for highway speeds of 65 - 72 (give or take).

Ron and I exchanged an email or two since we got back home. I wanted to let him know that I was going to put this in the forum to get some suggestions but also to assure him that this in no way is suggesting that there was something done incorrectly by the guys in the shop. They’ve installed the same rear tire on more than 100 Spyders and no one else has reported this problem to him. Bikes that were being ridden 2-up and were pulling a trailer included. He suggested that there could be a problem with the clutch pack not fully engaging, creating a chatter which would then transfer to the belt. I think we both wish that I’d accepted the offer of swapping tires while we were still there. I don’t have any experience driving vehicles with wet clutches, and I am by no stretch of the imagination proclaiming to be an expert on the Spyder. Heck, I’m just getting comfortable with what I do know how to do on it. But I’ve got 30 plus years of industrial mechanical maintenance under my belt, and the fact the vibration can be duplicated and is limited to the specific RPM range and stops at 3600 every time is one of those things that we’d key in on as a repeatable condition.

After reading the posts in this thread, I'm getting the impression that the belt tension should be reduced, and I need to get a tension gauge. Am I reading it correctly?

 

[troop]

During our ride from Greenville, TN to Piney Flats, TN a couple of weeks ago after the tires had been replaced by the guys at BajaRon’s shop, we experienced an unexpected vibration while climbing a hill at 72 mph. It wasn’t coming from the tires or suspension, but instead felt like the drive belt and was felt in the footrests and seat, not in the handlebars. It didn’t stop until we slowed down and then didn’t reappear until much later in the day under similar circumstances. We changed our plans for the next day and drove back down to Greenville to see the guys at the shop and try to figure it out.

We pulled in and met Daniel for the first time and I described the problem to him. He took the bike it for a ride and when he returned, he checked the belt tension and adjusted it from 200 to 230 lbs. My wife and I test rode again and confirmed the problem was still present. Back at the shop Daniel hopped on with me and we took another ride, paying attention to gear and rpm. We were testing on a local rural road, maybe 5 miles from the shop. It had curves and hills that helped to duplicate the conditions where we first experienced the vibration. From a stop at the bottom of a rather long hill (not sure of the grade), I worked through the gears at near full throttle with the goal of getting up to 70 mph before we got to the top. The bike rode smoothly through all the gear shifts until we went into 6th gear. I don’t recall the speed, low to mid 60’s maybe, but the rpm’s were at 3100 to 3200.

Daniel asked if he could check the belt damper, and when he pulled it off, we found a slight amount of play in the roller. He replaced it with a new one then test rode again but found the problem still present. All gears smooth until switching to 6th while climbing a hill at 3200(ish) rpms.

Back at the shop again, he checked the rear sprocket grommets and found them to be present and in good shape. Daniel was very focused on the problem, and he worked hard on a resolution. At one point he offered to change the rear tire again to a size slightly smaller than what was installed, but I declined. We left the shop with the feeling that the vibration was a result of lugging the engine while riding two-up and fully loaded.

While Daniel was working on our bike, my wife and I had opportunity to meet and talk to Ron. He’s obviously very knowledgeable but also a very pleasant man who we enjoyed talking with. We complemented him on his crew and their interaction with their customers. Working with Adrian, Paige, and Daniel was an absolute pleasure. Can’t speak highly enough of them all.

While riding after leaving Greenville, I was able to isolate when the vibration occurs. I’m feeling confident that it is coming from the drive belt.
With us riding 2-up, and the storage compartments loaded up full, the vibration occurred between 3200 & 3500 rpm, regardless of what gear we were in and if enough throttle load is applied. When 3600 rpm is reached, the vibration stops immediately. It is also felt when cruising at 3600 or higher and a dip in the road surface is encountered that causes the suspension to compress.

When we got home and unloaded everything we rode back into town and found that vibration did not occur as easily.

This past weekend she and I took a ride on Sunday into SE Indiana and found some nice open and hilly country roads. I was cruising around 55 mph, in 5th gear and 3200 rpm. On a level surface, everything is smooth as silk. As we crested the hills, I found that when the bike felt a “negative G” the vibration reappeared for an instant. Same thing when we rode over a dip in the road. These would be attributed to very quick changes in belt tension if I’m correct. I also reconfirmed the same rpm and throttle load conditions that were mentioned above.

While riding around last weekend and making mental notes for this post, I got the impression that we’ve felt the vibration when the OEM tires were still installed, but maybe just once or twice, and they were just as brief as I described when rolling through a dip in the road.

So, my impression is that the vibration is coming from the drive belt, and it has just recently appeared because the new rear tire (Altimax RT45, 215/60 R15) is larger than what was removed (OEM Kenda), which lowered the RPM range for highway speeds of 65 - 72 (give or take).

Ron and I exchanged an email or two since we got back home. I wanted to let him know that I was going to put this in the forum to get some suggestions but also to assure him that this in no way is suggesting that there was something done incorrectly by the guys in the shop. They’ve installed the same rear tire on more than 100 Spyders and no one else has reported this problem to him. Bikes that were being ridden 2-up and were pulling a trailer included. He suggested that there could be a problem with the clutch pack not fully engaging, creating a chatter which would then transfer to the belt. I think we both wish that I’d accepted the offer of swapping tires while we were still there. I don’t have any experience driving vehicles with wet clutches, and I am by no stretch of the imagination proclaiming to be an expert on the Spyder. Heck, I’m just getting comfortable with what I do know how to do on it. But I’ve got 30 plus years of industrial mechanical maintenance under my belt, and the fact the vibration can be duplicated and is limited to the specific RPM range and stops at 3600 every time is one of those things that we’d key in on as a repeatable condition.

After reading the posts in this thread, I'm getting the impression that the belt tension should be reduced, and I need to get a tension gauge. Am I reading it correctly?

This is crazy, as I have the exact SAME situation !! At 1500 miles, I switched from the OEM tire to General RT45 215/60R15 Altimax. At the exact same rpm range, 3100-3300, I get the same vibration rumble. Feels like very light rumble strips through my left floorboard. I can accelerate thru it and not feel it. Only when I softly accel thru the range do I feel it. If I set my cruise at 3200 rpm (low 60's), it is not felt. I had the dealer check my belt alignment and gauge the tension. The belt tracks nicely, and the tension is set slightly less than the mid range of spec. The master tech also did not feel the rumble/vbration. I never felt this in the first 1500 miles that I had my OEM Kenda installed. I'm learning to live with it now, as with you, it is sometimes barely perceptible. I also thought of adding a Lamonster belt isolator, and still likely will, as the OEM isolator is quite weak. It'll be interesting to see if you come up with anything...

 

[Dasmoetorhead]

During our ride from Greenville, TN to Piney Flats, TN a couple of weeks ago after the tires had been replaced by the guys at BajaRon’s shop, we experienced an unexpected vibration while climbing a hill at 72 mph. It wasn’t coming from the tires or suspension, but instead felt like the drive belt and was felt in the footrests and seat, not in the handlebars. It didn’t stop until we slowed down and then didn’t reappear until much later in the day under similar circumstances. We changed our plans for the next day and drove back down to Greenville to see the guys at the shop and try to figure it out.

We pulled in and met Daniel for the first time and I described the problem to him. He took the bike it for a ride and when he returned, he checked the belt tension and adjusted it from 200 to 230 lbs. My wife and I test rode again and confirmed the problem was still present. Back at the shop Daniel hopped on with me and we took another ride, paying attention to gear and rpm. We were testing on a local rural road, maybe 5 miles from the shop. It had curves and hills that helped to duplicate the conditions where we first experienced the vibration. From a stop at the bottom of a rather long hill (not sure of the grade), I worked through the gears at near full throttle with the goal of getting up to 70 mph before we got to the top. The bike rode smoothly through all the gear shifts until we went into 6th gear. I don’t recall the speed, low to mid 60’s maybe, but the rpm’s were at 3100 to 3200.

Daniel asked if he could check the belt damper, and when he pulled it off, we found a slight amount of play in the roller. He replaced it with a new one then test rode again but found the problem still present. All gears smooth until switching to 6th while climbing a hill at 3200(ish) rpms.

Back at the shop again, he checked the rear sprocket grommets and found them to be present and in good shape. Daniel was very focused on the problem, and he worked hard on a resolution. At one point he offered to change the rear tire again to a size slightly smaller than what was installed, but I declined. We left the shop with the feeling that the vibration was a result of lugging the engine while riding two-up and fully loaded.

While Daniel was working on our bike, my wife and I had opportunity to meet and talk to Ron. He’s obviously very knowledgeable but also a very pleasant man who we enjoyed talking with. We complemented him on his crew and their interaction with their customers. Working with Adrian, Paige, and Daniel was an absolute pleasure. Can’t speak highly enough of them all.

While riding after leaving Greenville, I was able to isolate when the vibration occurs. I’m feeling confident that it is coming from the drive belt.
With us riding 2-up, and the storage compartments loaded up full, the vibration occurred between 3200 & 3500 rpm, regardless of what gear we were in and if enough throttle load is applied. When 3600 rpm is reached, the vibration stops immediately. It is also felt when cruising at 3600 or higher and a dip in the road surface is encountered that causes the suspension to compress.

When we got home and unloaded everything we rode back into town and found that vibration did not occur as easily.

This past weekend she and I took a ride on Sunday into SE Indiana and found some nice open and hilly country roads. I was cruising around 55 mph, in 5th gear and 3200 rpm. On a level surface, everything is smooth as silk. As we crested the hills, I found that when the bike felt a “negative G” the vibration reappeared for an instant. Same thing when we rode over a dip in the road. These would be attributed to very quick changes in belt tension if I’m correct. I also reconfirmed the same rpm and throttle load conditions that were mentioned above.

While riding around last weekend and making mental notes for this post, I got the impression that we’ve felt the vibration when the OEM tires were still installed, but maybe just once or twice, and they were just as brief as I described when rolling through a dip in the road.

So, my impression is that the vibration is coming from the drive belt, and it has just recently appeared because the new rear tire (Altimax RT45, 215/60 R15) is larger than what was removed (OEM Kenda), which lowered the RPM range for highway speeds of 65 - 72 (give or take).

Ron and I exchanged an email or two since we got back home. I wanted to let him know that I was going to put this in the forum to get some suggestions but also to assure him that this in no way is suggesting that there was something done incorrectly by the guys in the shop. They’ve installed the same rear tire on more than 100 Spyders and no one else has reported this problem to him. Bikes that were being ridden 2-up and were pulling a trailer included. He suggested that there could be a problem with the clutch pack not fully engaging, creating a chatter which would then transfer to the belt. I think we both wish that I’d accepted the offer of swapping tires while we were still there. I don’t have any experience driving vehicles with wet clutches, and I am by no stretch of the imagination proclaiming to be an expert on the Spyder. Heck, I’m just getting comfortable with what I do know how to do on it. But I’ve got 30 plus years of industrial mechanical maintenance under my belt, and the fact the vibration can be duplicated and is limited to the specific RPM range and stops at 3600 every time is one of those things that we’d key in on as a repeatable condition.

After reading the posts in this thread, I'm getting the impression that the belt tension should be reduced, and I need to get a tension gauge. Am I reading it correctly?

I know we talked about this during one of our stops, and I noted the exact same vibration with the exact same tires as you. I didn't have this vibration with the stock Kendas. Hmmmmm.
As far as belt alingment and tension goes it's perfect. I'm not getting any abnormal belt dust on the rear wheel or front sprocket area, and the belt looks good.

 

[Dasmoetorhead]

Update. I really don't think it had anything to do with my tires. They're perfectly balanced and there is no tire or wheel vibration at any speed. The handlebars don't shake even when I'm doing 70 mph and let go of them. It's got to be the belt tension. I've just been too lazy to adjust it again.

 

[troop]

Update. I really don't think it had anything to do with my tires. There perfectly balanced and there is no tire or wheel vibration at any speed. The handle bars don't shake even when I'm doing 70 mph and let go of them. It's got to be the belt tension. I've just been to lazy to adjust it again.

Yup ... same here. Everything steers and tracks smoothly with no vibration. Just at slow accel between 3100-3300 rpm. On my past F3S, with 89t rear pulley (shorter belt), I used a couple non Altimax 215/60R15 tires w/out belt issues. Just a weird anomaly on (3) of us using the same tire.

 

[Poppie65]

Yup ... same here. Everything steers and tracks smoothly with no vibration. Just at slow accel between 3100-3300 rpm. On my past F3S, with 89t rear pulley (shorter belt), I used a couple non Altimax 215/60R15 tires w/out belt issues. Just a weird anomaly on (3) of us using the same tire.

I'm willing to bet that there are quite a few more out there who are also dealing with this

 

[Poppie65]

I'm still thinking that this isn't so much the tension as it is the rpm range that we're driving in.

 

[WRCLVR]

This is crazy, as I have the exact SAME situation!! At 1500 miles, I switched from the OEM tire to General RT45 215/60R15 Altimax. At the exact same rpm range, 3100-3300, I get the same vibration rumble. Feels like very light rumble strips through my left floorboard. I can accelerate thru it and not feel it. Only when I softly accel thru the range do I feel it. If I set my cruise at 3200 rpm (low 60's), it is not felt. I had the dealer check my belt alignment and gauge the tension. The belt tracks nicely, and the tension is set slightly less than the mid-range of spec. The master tech also did not feel the rumble/vibration. I never felt this in the first 1500 miles that I had my OEM Kenda installed. I'm learning to live with it now, as with you, it is sometimes barely perceptible. I also thought of adding a Lamonster belt isolator, and still likely will, as the OEM isolator is quite weak. It'll be interesting to see if you come up with anything...

Is it possible the vibration existed before the tire swap, and you just did not notice it? That may mean the stiffer side wall is exacerbating the driveline vibrations. Those belt dampers are not too expensive, might be worth a shot, just need to inspect and test the roller at periodic intervals... remove and regrease if needed and it doesn't roll freely.

 

[troop]

is it possible the vibration existed before the tire swap, and you just did not notice it? That may mean the stiffer side wall is exacerbating the driveline vibrations. Those belt damper are not too expensive, might be worth a shot, just need to inspect and test the roller at periodic intervals...remove and regrease if needed and doesnt roll freely.

Had 1500 miles on the OEM Kenda and didn't feel it. Had a upgraded belt isolator on my past F3S. Will do it again..

 

[Dasmoetorhead]

I don't know for a fact, but I would think the original Kenda rear tire weighs quite a bit less than the General RT 45 Altimax.
If this is the case, the heavier tire is putting more stress on anything it's associated with. Like bearings, bushings, rear sprocket, and I would imagine the drive belt.
So if any of my ramblings are correct this added rotating mass could be the cause of the belt vibrations. Could be a harmonic thing between tire and belt. IDK
It's real, I know that for sure.

 

[Dasmoetorhead]

Yup ... same here. Everything steers and tracks smoothly with no vibration. Just at slow accel between 3100-3300 rpm. On my past F3S, with 89t rear pulley (shorter belt), I used a couple non Altimax 215/60R15 tires w/out belt issues. Just a weird anomaly on (3) of us using the same tire.

It is weird.

 

[Poppie65]

My theory is that the vibration potential has always been there, and it would be somewhat easy for other riders who still have the OEM size rear tire to confirm (assuming that everyone is riding with their belt tension set to MFR specs). If they were to duplicate the riding conditions, maintain steady speed between 3200-3500 RPM in 6th gear, then give it a ton of throttle, or climb a hill while adding throttle. I don't know what speed this RPM range translates to, but thinking it's in the high 70s?? As previously mentioned, when my bike hits 3600 rpm the vibration stops instantly.
If we could get a handful of different riders (with the OEM tire size) to try this out we might learn something. My guess is that there's a reason why BRP put a smaller diameter rear tire back there.

 

[spyderfish]

I have very similar issues since getting my 2021. After observing for 2 years, I believe the issue is from the 1330 engine, or some rotating member of the clutch mechanism. My solution is to run at 3500 rpm or higher. I could spend a lot of time explaining my observations and reasoning in more detail, but better to not sway your judgement.

Maybe think about this other possible causal factor as you investigate further?

 

[Dasmoetorhead]

I have very similar issues since getting my 2021. After observing for 2 years, I believe the issue is from the 1330 engine, or some rotating member of the clutch mechanism. My solution is to run at 3500 rpm or higher. I could spend a lot of time explaining my observations and reasoning in more detail, but better to not sway your judgement.

Maybe think about this other possible causal factor as you investigate further?

I can't speak for the rest of the concerned riders, but I try to stay out of the 3200-3240 RPM range. I'm living with it until the cure jumps out at me one day. Until then, I continue to ride; but I do check the drive train often.

 

[Mikey]

Is it possible the vibration existed before the tire swap, and you just did not notice it? That may mean the stiffer side wall is exacerbating the driveline vibrations. Those belt dampers are not too expensive, might be worth a shot, just need to inspect and test the roller at periodic intervals... remove and regrease if needed and it doesn't roll freely.

My thoughts on that are, when it vibrates like my dad's 65 Electra glide, I will put a dampener on. I mean come on guys and gals as we roll down the road you feel everything, different road surfaces, little cracks, everything. A small vibration at one speed, roll thru it!

 

[Dasmoetorhead]

My thoughts on that are, when it vibrates like my dad's 65 Electra glide, I will put a dampener on. I mean come on guys and gals as we roll down the road you feel everything, different road surfaces, little cracks, everything. A small vibration at one speed, roll thru it!

The vibration and noise I'm experiencing is not as you say small. I get belt fluttering sounds and vibration at the same time. I'm having to learn how to lessen the effect at the same time always remembering what rpm range I'm in and also what gear. If I'm in 6th gear I can't just wack the throttle. If I do I will be rewarded with vibration and noise. So it ain't a small inconvenience.

 

[Poppie65]

The vibration and noise I'm experiencing is not as you say small. I get belt fluttering sounds and vibration at the same time. I'm having to learn how to lessen the effect at the same time always remembering what rpm range I'm in and also what gear. If I'm in 6th gear I can't just wack the throttle. If I do I will be rewarded with vibration and noise. So it ain't a small inconvenience.

Thanks for this response, you said it better than I was gonna. I'm experiencing this exact phenomenon.