F3 Front Sprocket Inspection

[Machinegunner]

Harley uses a compensating sprocket on the crankshaft to eliminate the alternating pulses from their uneven firing order. It is mechanical so should not wear as easily as rubber. It protects their whole drive train.

[eddieshep999]

With all the talk of red rust indicating a possible sign of the early stages of the Front Sprocket failures, it may be worth investigating a substance that may prevent the rust in the first place

One product we can purchase in the UK is ACF-50 Not sure if it’s avaible in the USA
There may be other substances that could do the same job and are available and worth looking at

He is some background on ACF-50

http://www.acf-50.co.uk/motorcycle.htm

[Roadster Renovations]

With all the talk of red rust indicating a possible sign of the early stages of the Front Sprocket failures, it may be worth investigating a substance that may prevent the rust in the first place

One product we can purchase in the UK is ACF-50 Not sure if it’s avaible in the USA
There may be other substances that could do the same job and are available and worth looking at

He is some background on ACF-50

http://www.acf-50.co.uk/motorcycle.htm

Just did a quick check on Amazon. https://www.amazon.com/s/ref=nb_sb_n...ywords=+ACF-50
So it is doable here!! May be better than molly if it does all that is advertised!

[EETHER54]

Just did a quick check on Amazon. https://www.amazon.com/s/ref=nb_sb_n...ywords=+ACF-50
So it is doable here!! May be better than molly if it does all that is advertised!

The red rust isn't the cause of the issue, it's just a byproduct of the spines failing. There is no real sort of coating on the sprocket splines, just bare on bare metal. Our first F3 that had complete spline failure was a manual shift, so I'm not sure how strong the correlation between the SE6 clunk and the issue is. Our shop hasn't seen this specific type of failure on the 1330 RTs at this point.

IMHO I believe there is less bearing surface between the backside of the sprocket and the shaft as compared to the 990 engine. This coupled with improper torque of the bolt likely exacerbated by BRP's somewhat irritating habit of preloading bolts with loctite is what is causing the issue. What I have observed would seem to indicate the design relies heavily on arresting any movement with solely the tension of the bolt. If it isn't torqued properly it eventually allows movement of the splines and it's all downhill from there.

The loctite 660 is designed to arrest any potential for movement, frankly making the clamping force of the bolt much less important. I understand that heat will have to be used to remove the sprocket eventually, but that really isn't something that you should have to replace that often. Replacing the seal behind it would not be that difficult as infrequently as this operation would need to be undertaken. Fwiw, certain years of ZX6s came from the factory with a obscenely tight front sprocket nut. The advice from the kawasaki tech department was to heat the nut red hot and hit it with an impact gun. The seal obviously needed to be replaced but there was never another issue...

While there may be more than one way to fix the issue, I would recommend anyone still under warranty to go the loctite route, or rather, make sure that your dealership does so for you.

[TexasZ]

The red rust isn't the cause of the issue, it's just a byproduct of the spines failing. There is no real sort of coating on the sprocket splines, just bare on bare metal. Our first F3 that had complete spline failure was a manual shift, so I'm not sure how strong the correlation between the SE6 clunk and the issue is. Our shop hasn't seen this specific type of failure on the 1330 RTs at this point.

IMHO I believe there is less bearing surface between the backside of the sprocket and the shaft as compared to the 990 engine. This coupled with improper torque of the bolt likely exacerbated by BRP's somewhat irritating habit of preloading bolts with loctite is what is causing the issue. What I have observed would seem to indicate the design relies heavily on arresting any movement with solely the tension of the bolt. If it isn't torqued properly it eventually allows movement of the splines and it's all downhill from there.

The loctite 660 is designed to arrest any potential for movement, frankly making the clamping force of the bolt much less important. I understand that heat will have to be used to remove the sprocket eventually, but that really isn't something that you should have to replace that often. Replacing the seal behind it would not be that difficult as infrequently as this operation would need to be undertaken. Fwiw, certain years of ZX6s came from the factory with a obscenely tight front sprocket nut. The advice from the kawasaki tech department was to heat the nut red hot and hit it with an impact gun. The seal obviously needed to be replaced but there was never another issue...

While there may be more than one way to fix the issue, I would recommend anyone still under warranty to go the loctite route, or rather, make sure that your dealership does so for you.

Well said, clearly explained. Thanks once again for the info you have provided in your multiple posts, much appreciated!!!
If I was having the dealership do the job I would have a tube of the 660 in my hand to give them when I made the request for it to be used.

Edited to add that I checked the service manual and it appears that if the seal ever needed to be replaced it is no big deal or hassle to do it.

[Peter Aawen]

.....
If I was having the dealership do the job I would have a tube of the 660 in my hand to give them when I made the request for it to be used.

Sadly, it seems that at many dealers, even handing over the stuff you want them to use doesn't necessarily mean it'll end up being used on your (or even any) Spyder!! Unless you actually WATCH them doing the job, you'll never know for sure....

[TexasZ]

Sadly, it seems that at many dealers, even handing over the stuff you want them to use doesn't necessarily mean it'll end up being used on your (or even any) Spyder!! Unless you actually WATCH them doing the job, you'll never know for sure....

So true, that's exactly the reason that I will personally do the job myself.

[Roadster Renovations]

Well said, clearly explained. Thanks once again for the info you have provided in your multiple posts, much appreciated!!!
If I was having the dealership do the job I would have a tube of the 660 in my hand to give them when I made the request for it to be used.

Edited to add that I checked the service manual and it appears that if the seal ever needed to be replaced it is no big deal or hassle to do it.

Didn't check on the seal replacement, so that puts the 660 back up the running for me as a possibility.

[Roadster Renovations]

You all know that BRP is watching this thread closely and that we will all probably figure out which fix works that they will then adopt! With the entire knowledge that everyone has brought to this thread, there is no way that they could even hire that much intellectual wisdom and experience. Sad that it came to that, but glad that it did.