PMK, I'm glad you've been able to clarify exactly what is happening to cause these failures - thank you.

However, I disagree with you on the point: Consider, if the splines were removed, would the bolt and washer alone be adequate to propel the Spyder forward. Obviously, no. The splines are responsible for 99.999999% of making the Spyder drive go to the wheel.

In my experience, the splines are not responsible for 'making the Spyder drive go to the wheels.' It is the clamping force of the bolt which does this by locking the component solidly together. This was in fact acknowledged in the TSB which BRP released back in 2009 when the problem first arose. The pulley was not designed to be a wear item but rather a sacrificial item IF adequate clamping force was ever lost, or never initially applied as we now see again.

FWIW, I bought my GS in Dec 2009 soon after this issue first arose and the release of that TSB. I purchased a new OEM bolt, did some minor research on what torque a bolt of that spec could take and found it to be about 10-15% higher (from memory) than what BRP recommended in the TSB, so I applied that higher torque. To this day and 96,000km later, the pulley on my trike shows no sign of red dust.

It seems to me that BRP have a short corporate memory in this regard.

I've suggested that folks apply Loctite 660 and 7471 primer to the splines if they find fretting in the early stage which, when effectively clamped with the bolt, may/should/could eliminate fretting.


PS I have seen a number of other automotive and industrial applications which rely on clamping force to transmit torque to splined components and I've seen a number where one part or the other is sacrificial.