Front Sprocket Again!!

[fatboy]

down shifting to brake could potentially loosen the bolt holding sprocket then working pulley back and forth

[Mikey]

I think if down shifting is a cause, there would be a boat load of all years and makes with this problem!! My 2 cents!! I think and still think, that it's a case of ether bad parts or some one's having rough mornings and not installing the things right from the start! Monday's and Friday's are hard for some people.

[Mikey]

down shifting to brake could potentially loosen the bolt holding sprocket then working pulley back and forth

On a spline shaft!?!?

[fatboy]

yes mikey not everybody use the trans for a brake

[Spyderjuice]

Is it possible the motor mounts are off just a tiny bit making the pressure on the sprocket a little off to one side and causing undue wear?

Juice

[Snoking1127]

the only diff in the two sprockets is the white coating

You did a metallurgy test on an old one and a new one, and found them the same?

[Chasinsparks]

down shifting to brake could potentially loosen the bolt holding sprocket then working pulley back and forth

I guess maybe. If that is the case it need to be addressed in the engineering department no way their parts should be failing at 5175 miles with mild downshifting.

[bmccaffrey]

Quality Control Issue!!

[bikerchris1270]

the only diff in the two sprockets is the white coating

The white pulley(updated version) has a slightly different tooth profile to eliminate the whining sound from, believe it or not, air being trapped between cog and belt. The Smoaks You Tube video discusses this……..mines quieter.

[Snoking1127]

The white pulley(updated version) has a slightly different tooth profile to eliminate the whining sound from, believe it or not, air being trapped between cog and belt. The Smoaks You Tube video discusses this……..mines quieter.

But that has little to do with the spline wear on the earlier pulleys. Unless they changed something in the casing material the spline stripping out may still be present. (It is only a different color? I think not!)

[IdahoMtnSpyder]

the only diff in the two sprockets is the white coating

Correct that. The only visible difference is the white coating. My guess is they either changed the steel that is used for them, or the heat treat process after the splines are cut. Or, maybe the supplier did not heat treat the earlier ones correctly, or had a batch not properly heat treated. There may have been no way to know for certain what sprockets were or were not properly heat treated. Maybe the splines are now cut for a tighter fit.

[fatboy]

you do not want the metal in the pulley hardened enough to wear the splines on the crank then you have a big problem believe it or not the spyder knows down shifts that wont hurt its self

[Mikey]

Now we are getting to the bottom of it!!

[IdahoMtnSpyder]

you do not want the metal in the pulley hardened enough to wear the splines on the crank then you have a big problem believe it or not the spyder knows down shifts that wont hurt its self

That's the balancing game the designers have to play. The pulley needs to be soft enough to be the sacrificial piece and hard enough not to wear down.

[fatboy]

if the bolt backs of from the torque of using the trans as a brake it does not matter how hard it is

[EdMat]

if the bolt backs of from the torque of using the trans as a brake it does not matter how hard it is

Looks like it would do the same thing when it auto downshifted then.

[fatboy]

the auto downshift is not using the compression of the engine as a brake

[IdahoMtnSpyder]

if the bolt backs of from the torque of using the trans as a brake it does not matter how hard it is

The only way downshifting will loosen the bolt is for the sprocket to have rotational movement with respect to the shaft. The red dust is the result of fretting. Industrial installations contend with the same issue. The two most common causes of fretting, from what I read, is misalignment of the mating splines, or rotational vibration. In applications where there isn't a flywheel to counteract changes in rotational speed there is a good possibility of rotational vibration. That may be what is causing the Spyder sprockets to wear. Or, maybe the sprocket tooth configuration that was causing the belt whine may have been inducing rotational vibration in the sprocket.

In any case fretting is not subject to an easy solution, and has been the focus of many engineers in industry. It's far to complicated for us mere Spyder riding mortals to solve. I'm an engineer and I had difficulty understanding some of the discussions about spline fretting.

[BLUEKNIGHT911]

The only way downshifting will loosen the bolt is for the sprocket to have rotational movement with respect to the shaft. The red dust is the result of fretting. Industrial installations contend with the same issue. The two most common causes of fretting, from what I read, is misalignment of the mating splines, or rotational vibration. In applications where there isn't a flywheel to counteract changes in rotational speed there is a good possibility of rotational vibration. That may be what is causing the Spyder sprockets to wear. Or, maybe the sprocket tooth configuration that was causing the belt whine may have been inducing rotational vibration in the sprocket.

In any case fretting is not subject to an easy solution, and has been the focus of many engineers in industry. It's far to complicated for us mere Spyder riding mortals to solve. I'm an engineer and I had difficulty understanding some of the discussions about spline fretting.

.... To the best of my knowledge ( I read every Red Dust issue post ) this problem has only showed up in the models made after 2013 ans mostly to the F-3 .... I think BRP may have changed the main supplier of these parts, or the specs for them ..... BRP has done this with tires and DESS modules .... jmho .... Mike

[PMK]

The only way downshifting will loosen the bolt is for the sprocket to have rotational movement with respect to the shaft. The red dust is the result of fretting. Industrial installations contend with the same issue. The two most common causes of fretting, from what I read, is misalignment of the mating splines, or rotational vibration. In applications where there isn't a flywheel to counteract changes in rotational speed there is a good possibility of rotational vibration. That may be what is causing the Spyder sprockets to wear. Or, maybe the sprocket tooth configuration that was causing the belt whine may have been inducing rotational vibration in the sprocket.

In any case fretting is not subject to an easy solution, and has been the focus of many engineers in industry. It's far to complicated for us mere Spyder riding mortals to solve. I'm an engineer and I had difficulty understanding some of the discussions about spline fretting.

Fretting corrosion is not that difficult to contend with. You either redesign the interface of the joint to prevent movement, or you apply a lubricant and accomplish maintenance events to clean and inspect the splines for wear, if no wear is indicated, relubricate the splines and correctly reassemble.

As I have mentioned previously, the pulley is a wear item, same as sprockets with a chain. Can Am should not recall, but rather publish a service bulletin advising the service intervals for inspecting the splines.

[Snoking1127]

Fretting corrosion is not that difficult to contend with. You either redesign the interface of the joint to prevent movement, or you apply a lubricant and accomplish maintenance events to clean and inspect the splines for wear, if no wear is indicated, relubricate the splines and correctly reassemble.

As I have mentioned previously, the pulley is a wear item, same as sprockets with a chain. Can Am should not recall, but rather publish a service bulletin advising the service intervals for inspecting the splines.

I just inspected mine and re-lubed it at 10K miles, appear as good as new with lube apparent when I took it apart.

[Chasinsparks]

We shall see

[Freddy]

.... To the best of my knowledge ( I read every Red Dust issue post ) this problem has only showed up in the models made after 2013 ans mostly to the F-3 .... I think BRP may have changed the main supplier of these parts, or the specs for them ..... BRP has done this with tires and DESS modules .... jmho .... Mike

https://www.spyderlovers.com/forums/...Bulletin/page3

[BLUEKNIGHT911]

https://www.spyderlovers.com/forums/...Bulletin/page3

OK I read that .... it says NOTHING about " fretting " .... and I think that is the major issue .... Mike

[EdMat]

the auto downshift is not using the compression of the engine as a brake

You need to tell my RTL that, when I am coasting to a red light I sure feel every change and the associated speed decrease.