F3 Vibration

[Samson]

Yes, I actually gave them the number and none of them could find the part in the system. I will try again next week. Thanks

 

[bigwhammy]

Yes, I actually gave them the number and none of them could find the part in the system. I will try again next week. Thanks

Ordered one through our dealer about 10 days ago. Per my receipt- idler belt kit (PN 219800412) (I think Bruce called it an idler wheel kit.)
Part number was on BRP site but not in their local system . They had to enter the part into their own system to price it accordingly.
Paid $53.20 Australian dollars inclusive of our 10% GSTax. Expected delivery 22 September.

 

[Samson]

I heard back from the dealer, after calling BRP Care from this forum posting they found the part. It will not be available till 9/26/16.

 

[MrBones]

Guess I be lucky as I have never felt vibration at all! 2015 F3 s.

 

[Samson]

Interesting: I had the Laser alignment done was off 1/16" left front, 3/8" Right front per the dealer, have 22.5 PSI in Front tires, 27 PSI in rear tire, 55 psi in air shock. Went for 100 mile ride this morning at speeds up to about 80 and NO vibrations at any speed. I purchased a very accurate air gauge so just not sure what did the trick, alignment, air pressure, rear shock ?? Maybe all of the above.

I will order the new BRP part and have on the shelf just in case. The new vibe free zone from 3500 to 4200 in 6th is now a real pleasure as I think this zone is a sweet spot for this bike. Very comfy . Hope this helps others

 

[MrBones]

For me I have no idea what your complaining about! I just ride and enjoy mine as I feel no vib at all.

 

[Wildrice]

Wildrice, I have not heard of anyone else conducting this test and I would be surprised if BRP and Rotax had not done extensive testing prior to using the 1330 ACE engine? I was talking with an engineer buddy of mine about the potential belt vibration and he acknowledged that from a dynamic standpoint, when the engine shaft connected to the front sprocket is pulling the belt forward under acceleration or up hills, the tension on the upper half of the belt is likely to be greater than the lower half of the belt after it leaves the front sprocket headed toward the rear sprocket. He suspected that the "slack" in the lower side of the belt may be contributing much of the vibration and that an idler pulley would simply reduce the harmonic vibrations set up by these design conditions. I know you mentioned that you have used two different strategies for idler pulleys with limited success. As is pointed out in the BRP technical service bulletin that addresses belt tension and vibration onset, BRP acknowledges and I agree that some people are more sensitive to the vibrations than others. In my own personsonal F3-S, I notice some vibration when accelerating and going up hills but do not find it objectionable or something that causes concern but that is based on my own idiosyncratic proprioceptive experiences.

A Google search came up with a company (PCB piezotronics) that makes equipment to routinely monitor vibration shaft issues addresses some of the ways that a manufacturer/plant can monitor these vibrations: http://www.pcb.com/PdMProcess/gclid/CKbC4JnWkc8CFQhkhgodGh8Oww

I can't imagine with all of BRP's resources and especially testing and building of jet aircraft that they do not have very sophisticated measurement equipment that can be or has been used to assess the concerns of vibrations in the F3?

It is not required to remove the belt to prove the engine is the problem. Just park the Spyder--put the Spyder in neutral with the brake on. Now rev the engine between 3K & 4K rpm. If the belt is moving while we do this experiment---Houston--we have a problem :-( But wanna bet any $$$ that you will feel the engine vibration with a stationary belt. I am open for All Bet Takers--just name the amount of the wager & an independent party to hold the $$$ money-------you will lose.

 

[Wildrice]

Somewhere else on here this was brought up and what was thought is that it is an engine vibration at a specific speed when in 6th gear not the belt. When I felt it on mine I down shifted out of 6th gear and the vibration was gone.

The reason your vibration disappeared was the change in the RPM---not the gear itself, if you downshifted to 5 th gear ride is at the same RPM you had felt it in 6th gear & the vibration will re-appear--it is the engine causing the problem.

 

[PowerSportsFan]

Fanastic post that removes opinions and feelings. Completely from an Engineering peri

The Spyder drive belt is a tensioned string system that transmits the drive pinion torque to the rear sprocket via the tension of the upper part of the belt. The natural response of a string system is to vibrate when stretched and released at different speeds and strengths. The accumulated energy of these movements in the belt will be dissipated throughout the entire vehicle through the drive pinion and the rear sprocket.

A momentary belt vibration may be felt when the vehicle is driven under increased load/torque conditions (acceleration and/or going uphill). When the belt tension is within specification, the phenomenon may occur between 3800rpm and 4300rpm in 6th gear on 1330 engines (or between 4700rpm and 5500rpm in 5th gear on 991 engines). This vibration is felt through the handle bars, the foot rests and the seat. The harmonic vibration described here is considered "normal behavior" for such a belt drive system. In no cases is there any damage produced to the unit's mechanical components by this harmonic vibration.

Although belt vibration cannot be entirely eliminated, changing the belt tension will change the RPM/Speed at which the vibration occurs and the amplitude of its occurrences. Adjusting the drive belt tension lower will reduce the vibration level. Under high load/torque conditions, the vibration levels are diminished in amplitude and the RPM which the vibration occurs is lowered by roughly 400rpm.

For someone driving regularly between 68 and 75mph having a lower belt tension means they will feel a belt vibration when going through speeds of 62 to 65mph but at a lower amplitude, and feel less vibrations under acceleration and cruising speed. For someone driving regularly between 62 to 65mph having a belt tension set at specification means they will not feel as much the belt vibration since it occurs at higher RPM/Speed 68 and 75mph.

Statically, the belt tension is based on the distance between the drive pinion and the rear sprocket. The belt can be preset to a specific value using the tension adjustment procedure. While standing on its wheels, the belt tension of the Spyder increases due to the rotation motion of the swing arm. Further additional weight on the vehicle (driver, passenger and luggage) further increases the static tension of the belt.

Dynamically, the big picture is that the belt tension continuously varies with the road surface irregularities. Furthermore, to transmit torque from the drive pinion to the rear sprocket, the given amount of tension is decreased from the lower portion of the belt and transmitted to the upper portion of the belt. The inverse is also true when the vehicle is under deceleration. The amount of tension transferred depends on the acceleration or deceleration of the vehicle and slope of the road.

The belt tension is the factor which determines the belt vibration. The engine speed at which vibration would occur depends solely on the tension of the belt since the length and mass of the belt remains relatively constant. More vibration is transmitted to the vehicle when the tension is high. This effect can be explained by the fact that higher tension implies higher stiffness and higher stiffness implies higher transmissibility. This also explains why even though more vibrations are observed on the lower portion of the belt, only the vibration of the upper portion of the belt is strongly felt on the vehicle due to its higher transmissibility (because it has a higher tension in the majority of driving conditions).

At constant speed and zero road slope, the upper part of the belt has a higher tension than the lower part of the belt due to aerodynamic resistance. Under acceleration and/or hill climb conditions, the upper part of the belt further increases in tension. The degree of acceleration or hill climb proportionally dictates the engine speed at which occurs the belt vibration and the amplitudes of vibration transmitted to the vehicle.

By reducing the tension of the belt, the transmitted vibration at very low torque conditions can be completely removed. The transmitted vibration at higher torque is similar to that of the specification belt tension but occurs at slightly lower RPM/speed.

So basically, if you experience unpleasant vibrations have your drive belt tension checked at three different points of rotation of the rear wheel/sprocket and see how it varies, and compares to the vehicle's specification. If the belt tension changes more than 250N between 2 readings this would indicate an out of round rear sprocket which should be replaced. Otherwise, you can adjust the tension to change the speed and amplitude at which it occurs.

This is an awesome post, thank you Sledmaster. Looking at it from an Engineering and Vector Mechanics point of view as described by Sledmaster's post, makes complete sense and explains the various experiences (or lack there of) with the vibrations. Especially the very last sentence. It is always a good idea to ensure that the configuration items of a closed system are to spec (in this case the geometric perfection of the sprockets, tensions, alignments, etc...). But even if such a closed system is configured properly, the vibrations WILL happen when one or more of the variable value ranges are met. It's the nature of such a mechanical system. You can however adjust where/when the vibration happens. You can make it happen somewhere where you won't experience it much (or at all) by changing the configuration items (listed previously), or even by your interaction with the closed system (like riding style, shifting point, etc..).

If you read this post carefully, you will understand that there are several variables at work here -- not just one. And that is why this vibration experience is so dynamic across so many riders. It is not a matter of opinions, or rider experience, or mood, etc. In a way, everyone is right, and has found one or more (or none yet) of the variables that contribute to the vibration "issue". Totally makes sense. Thank you again Sledmaster.

Of course as stated previously, it is always a good idea still, to ensure that all tensions and alignments are to spec. Out-of-spec can itself be one of those contributing variables.

I have a 2015 Spyder F3S, as well as a 2014 Spyder RSS (bought the last yellow one here), both brand new from the dealer. I experience the vibrations on both of them, and my riding style causes the majority of these vibrations at the same points that are listed in Sledmaster's post above. But if I ride a bit more aggressive, then the vibration points can change, and vibration period shortens because I am riding more aggressively so I get through the vibration band much faster. And the reverse applies too. Also going uphill and downhill affects the dynamics of the vibration differently.

Happy and safe riding.

 

[Wildrice]

I have belt vibration in 3rd, 4th, 5th and 6th gear. It seemed to get worse as we rode yesterday. I noticed a lot more with a passenger than when I drove it home with no passenger. It appears to be mainly from 3600 to 4100 rpm's in the above mentioned gears. Annoying it is, vibrates the bars, mirrors, seat and footboards.

I love the Truth--when people state they can feel the vibration in most gears at a defined RPM range , mostly vibration within a 3200-4000 RPM range. Baffles me when people blame it on the belt. Everyone is entitled to their own opinion--yet none can claim reducing or increasing the RPM didn't make the vibration disappear--how's that work-anyway? Reducing the belt tension to the 150-160# Krikit tension range does help--so do the various belt roller assy's--both of these reduce the engine vibration felt--but the source of the problem is the engine. I do believe most engines vibration's reduce with more engine mileage--reduce but not significantly disappear.........
Darrell

 

[Wildrice]

This is an awesome post, thank you Sledmaster. Looking at it from an Engineering and Vector Mechanics point of view as described by Sledmaster's post, makes complete sense and explains the various experiences (or lack there of) with the vibrations. Especially the very last sentence. It is always a good idea to ensure that the configuration items of a closed system are to spec (in this case the geometric perfection of the sprockets, tensions, alignments, etc...). But even if such a closed system is configured properly, the vibrations WILL happen when one or more of the variable value ranges are met. It's the nature of such a mechanical system. You can however adjust where/when the vibration happens. You can make it happen somewhere where you won't experience it much (or at all) by changing the configuration items (listed previously), or even by your interaction with the closed system (like riding style, shifting point, etc..).

If you read this post carefully, you will understand that there are several variables at work here -- not just one. And that is why this vibration experience is so dynamic across so many riders. It is not a matter of opinions, or rider experience, or mood, etc. In a way, everyone is right, and has found one or more (or none yet) of the variables that contribute to the vibration "issue". Totally makes sense. Thank you again Sledmaster.

Of course as stated previously, it is always a good idea still, to ensure that all tensions and alignments are to spec. Out-of-spec can itself be one of those contributing variables.

I have a 2015 Spyder F3S, as well as a 2014 Spyder RSS (bought the last yellow one here), both brand new from the dealer. I experience the vibrations on both of them, and my riding style causes the majority of these vibrations at the same points that are listed in Sledmaster's post above. But if I ride a bit more aggressive, then the vibration points can change, and vibration period shortens because I am riding more aggressively so I get through the vibration band much faster. And the reverse applies too. Also going uphill and downhill affects the dynamics of the vibration differently.

Happy and safe riding.

Try in in the neutral gear--Spyder parked--with the belt being stationary- then explain to me why I still feel the vibration between 3K-4K RPM..
Darrell

 

[jcthorne]

The engine is the source of the vibration. Trouble is it sets up a harmonic strum in the belt that is much more forceful and felt much more strongly.

Adding the tensioner keeps this strum in the belt from occurring thus MUCH reducing what is felt.

My F3S now has just over 15k miles on it and yes, its MUCH smoother than Louise new F3-T. Its surely has gotten better with miles. Gets better gas milage too.

 

[jcthorne]

Has anyone received shipping on the BRP tensioner yet?

 

[spr_chicken]

Has anyone received shipping on the BRP tensioner yet?

I'm still waiting for mine. Dealer keeps telling me it's back ordered pending release from BRP. Checked on it today after being told 2 weeks ago it was supposed to be sent on the 14th and they told me that it is delayed until the 28th. Really unhappy with the delay.

 

[no chrome]

has anyone gotten the BRP tensioner installed yet?

 

[TexasSpyder]

Install video

Here is Lamonster's install vid.
http://www.lamonstergarage.com/news/f3-idler-kit-install/

 

[SPYD3R]

YUP

I HAD THE SAME ISSUE WAY BACK WHEN.....
ALL CHANGED UPON REPLACEMENT OF ALL THREE TIRES WITH OTHER-THAN-KENDA's....... NO MORE VIBRATIONS....
SPYD3R

 

[bigwhammy]

Advanced automotive physics

I HAD THE SAME ISSUE WAY BACK WHEN.....
ALL CHANGED UPON REPLACEMENT OF ALL THREE TIRES WITH OTHER-THAN-KENDA's....... NO MORE VIBRATIONS....
SPYD3R

As an Automotive engineering lecturer (retired) it is more complicated than going to the moon.
Vibrations Free and forced and affect phase and resonance. Simple Harmonic motion oscillations (displacement, velocity and acceleration).

Their are 8 different resonators / causes on the bike and combined, ALL with different (resonance, Harmonic motion, Oscillations) dependant on Mass, spring constants, damping constants, frequencies, amplitudes make for the overall resultant vibrations and noises.

You can try and fix some of these things that resonate. Just a few of the variables.
The first and major one is the belt (obvious to all who own an F3).It appears the BRP tensioner is sorting this out fairly cheaply.
Tires has any body found a good tire fix for an average riders weight. Note spyd3r. What were the tires?
Shock absorbers fit the best you can afford. slow and high speed dampening ie 5 stage
Speed variables hmmm stick to below 655mph.
Fix the engine vibrations, oils aint oils?


I spent 3 days at the track setting up my suspension for ME (cheated a bit using AutoTURN computer simulations for Eastern Creek racetrack).
When my wife gets on I have to change most settings and takes 5 minutes but well worth it.(compromise with belt setting).
The BRP R&D team need to spend some money on a few more computers but it comes down to profit margins.
To my knowledge there is no specific CAD program for 3 wheelers especially inclusive of rider variables.
AutoCAD, Matlab, Solidworks, ANSUS work bench, microstation, AutoTURN etc etc are not going to fix an F3 vibrations.

Like the RT that burns your leg... engineers forgot that a real person was going to have their leg their that does not take to heat very well.
I guess we can go on but everybody seems to be trying something but attacking all 8 would be good, not sure how we all become the same person/rider (weight etc).
Just have fun striving for perfection (dreaming) is very expensive.

 

[SPYD3R]

BIG WAMMY

As an Automotive engineering lecturer (retired) it is more complicated than going to the moon.
Vibrations Free and forced and affect phase and resonance. Simple Harmonic motion oscillations (displacement, velocity and acceleration).

Their are 8 different resonators / causes on the bike and combined, ALL with different (resonance, Harmonic motion, Oscillations) dependant on Mass, spring constants, damping constants, frequencies, amplitudes make for the overall resultant vibrations and noises.

You can try and fix some of these things that resonate. Just a few of the variables.
The first and major one is the belt (obvious to all who own an F3).It appears the BRP tensioner is sorting this out fairly cheaply.
Tires has any body found a good tire fix for an average riders weight. Note spyd3r. What were the tires?
Shock absorbers fit the best you can afford. slow and high speed dampening ie 5 stage
Speed variables hmmm stick to below 655mph.
Fix the engine vibrations, oils aint oils?

I spent 3 days at the track setting up my suspension for ME (cheated a bit using AutoTURN computer simulations for Eastern Creek racetrack).
When my wife gets on I have to change most settings and takes 5 minutes but well worth it.(compromise with belt setting).
The BRP R&D team need to spend some money on a few more computers but it comes down to profit margins.
To my knowledge there is no specific CAD program for 3 wheelers especially inclusive of rider variables.
AutoCAD, Matlab, Solidworks, ANSUS work bench, microstation, AutoTURN etc etc are not going to fix an F3 vibrations.

Like the RT that burns your leg... engineers forgot that a real person was going to have their leg their that does not take to heat very well.
I guess we can go on but everybody seems to be trying something but attacking all 8 would be good, not sure how we all become the same person/rider (weight etc).
Just have fun striving for perfection (dreaming) is very expensive.

Mr. BIG;
FRONT TIRES ARE THE HANKOOK, AND REAR IS A KUMHO....
AND I KEEP MY SPEED WELL BELOW 655MPH BECAUSE I REMOVED MY AFTER-BURNER.... :roflblack:
WHY I NO LONGER HAVE THE VIBRATION IS BEYOND ME, I CAN'T EXPLAIN IT... I JUST DON'T HAVE IT ANYMORE SINCE RELOADING THE RIMS WITH THESE TIRES... ANYONE ELSE FIND THIS TO BE TRUE WITH YOUR F3....?
SPYD3R

 

[Wildrice]

Somewhere else on here this was brought up and what was thought is that it is an engine vibration at a specific speed when in 6th gear not the belt. When I felt it on mine I down shifted out of 6th gear and the vibration was gone.

Did the engine RPM change when you downshifted ??