Thump @ clutch side...driver issue?

[Q. Arrius]

I've checked out the "thumping," threads previously posted....I just can't figure out which issue I actually have: a worn belt @ 1700 miles, worn jack shaft bearing, or driver teeth either skipping or binding.

Sled: Apex SE '12, 128 track, 144 (iirc?) studs...one double, one single per line, center only. Bought at zero miles....myself as only owner. Studs installed 1000 miles ago.

At the tail end of my last ride of the year, a metallic thump or popping could be felt from the clutch side, in my foot. It would pop once or twice...then once moving, it would go away. It wouldn't matter if I tried to ease into take-off or hammer down...it would be there. Again....it's more of a popping vs thump.

I cannot replicate it with the track in the air, and I tried to drive it across my shop floor. Other than tearing up my concrete...I could not get it to duplicate itself. When I had it in the air, I noticed my driver teeth have an odd wear to them.

Could the drivers be skipping and pulling out, as I accelerate? Ive seen many pictures posted here and in the Viper section, of drivers with far more mileage, but in new condition.

My next step will be to check my jack shaft bearing, and change belt. Could my wear be from the track being too tight?

Any help or thoughts would be appreciated. I will attach a photo of the teeth.

Q. Arrius

 

[MrSled]

I had a noise I looked for for 2 seasons.. found it was warn extrovert drivers hanging on to the track. I could only hear it at slow speeds. I would replace your belt first.. easiest check.

 

[Winderallday!]

Just a suggestion, not sure how many miles are on your sled, but a buddy of mine with an 11 SE Apex lost a few track clips at the end of the season and it made the same noise/thumping that you are describing.
Pull drive axle/speedo side bearing and check it over to rule it out as well.

 

[STAIN]

Also check the tightness of the bearing collar on the left drive bearing. I have seen 2 sleds with this identical noise created by this collar being loose.

 

[RTX]

My first check would be your belt.
Dont look at it in place. Remove it from the sled and check it over very well for any damage.
My next check would be the studs make sure all the heads on the studs are down flush with the track.
Any stud head exposed above the rubber are going to make noise when they run over the wheels and drivers.
Next inspect the entire track for missing or damaged track clips. Hang the rear of the sled in the air and look at how the drivers mesh with the track holes and clips while turning the entire track over the drivers.
Lastly i would check your bearings.
Not sure what you have for miles on them, but they could be due for a change.
Remember the sled is a 2012, even if it does not have lots of miles, water can get into the bearings while your riding it, then that water sits all summer and rust them up which will destroy them once they start spinning again.
Good luck

 

[Sasquatch]

Check your driveshaft bearing as well.

 

[Q. Arrius]

I believe I found and fixed the problem!

I replaced the belt, (1700 miles) and ran the track suspended.....but still could visually see and hear the thump. The belt guard plate below the secondary would show the vibration. Obviously, the plate isn't the problem....but it seemed to amplify the thump.

I made the mistake of not loosening the track and testing again, before I replaced the drive shaft bearing.....but once the bearing was replaced, and I re tightened the track, the thump is gone!

I did NOT tighten the defection in the track as much as I previously had. I have a scale on order, as my previous method was to just wing it. The bearing looked good....but for $40 it was a no-brainier to replace it.

Until snow arrives, and I can test it again, I'm going to assume it was the bearing. The thump developed at the END of a two day saddle bag trip....so I think the track tension would have shown up earlier. I can't imagine I had it so tight it damaged the bearing? I absolutely noticed a lot of drag and reduced gas mileage though.

Side note: I opened the bearing covers on the mini wheels I bought from Pioneer. His quality is fine, and I'm NOT knocking the products he sold....but after 1000 miles, the bearing seal let in so much grit and sand, the wheels would have failed in the next few hundred miles. I was able to clean them and re pack though...but they obviously must be watched much more closely than Yamaha wheels. At 17000.... The rest of my wheels are perfectly clean and greased inside.

Thank you to everyone, for the help!

Q. Arrius

 

[MrSled]

I believe I found and fixed the problem!

I replaced the belt, (1700 miles) and ran the track suspended.....but still could visually see and hear the thump. The belt guard plate below the secondary would show the vibration. Obviously, the plate isn't the problem....but it seemed to amplify the thump.

I made the mistake of not loosening the track and testing again, before I replaced the drive shaft bearing.....but once the bearing was replaced, and I re tightened the track, the thump is gone!

I did NOT tighten the defection in the track as much as I previously had. I have a scale on order, as my previous method was to just wing it. The bearing looked good....but for $40 it was a no-brainier to replace it.

Until snow arrives, and I can test it again, I'm going to assume it was the bearing. The thump developed at the END of a two day saddle bag trip....so I think the track tension would have shown up earlier. I can't imagine I had it so tight it damaged the bearing? I absolutely noticed a lot of drag and reduced gas mileage though.

Side note: I opened the bearing covers on the mini wheels I bought from Pioneer. His quality is fine, and I'm NOT knocking the products he sold....but after 1000 miles, the bearing seal let in so much grit and sand, the wheels would have failed in the next few hundred miles. I was able to clean them and re pack though...but they obviously must be watched much more closely than Yamaha wheels. At 17000.... The rest of my wheels are perfectly clean and greased inside.

Thank you to everyone, for the help!

Q. Arrius

Glad you found the problem. The small wheel bearings on those kits are hard to keep in them.

 

[Nugget19]

Arrius was that the problem? Did the popping go away after? I have the same sound in my RS Venture and it's driving me nuts. I had the track replaced and the popping/thumping went away for 200 Kim's then returned the same as before. Any comments are welcomed. Thanks

 

[Q. Arrius]

Yes, the thump / twang / popping went away.

I believe the track was simply too tight. I'm not sure though, if the track would get hung up on a driver, or even get the bearing out of sorts.....but once I ran the track looser, the problem stopped.

I would still replace the bearing....maybe even every two years. As a buddy says, it's cheap insurance.

Between a friend and myself, it got about 1500 miles this past season. So I'm certain the issue is gone.

I seem to recall I wanted the track tight, expecting stretch from the studs. Probably not the smartest move. It's not like I'm doing 120 mph and ballooning the track. Oh well....live and learn.

Q. Arrius