Rear drive belt issue

Dubbs_

Member
I know this has been beat to death but I haven't been able to find the answer I'm looking for...

I've had the bike a few months and only rode it a dozen times or so... The last time I rode it I gave it a good flogging and developed a rattle sound... Sounded kinda like a loose heat shield... But the only way to replicate it was to drive the bike... Kinda sounded like the drive chain was rubbing on something... So I took the cover off to inspect everything... Everything looked ok and the chain was adjusted to spec... Filled with new oil and test rode the bike to find the noise still there... While looking everything over I found that the top motor mount bolt was missing... Installed a new bolt but the noise was still there... Continued to look everything over and found that the belt was way too loose... This was strange to me because I'd checked it before and it was a tad on the loose side but still plenty tight... Well I just figured I must of rode it harder than the previous owner and put a good stretch on it... Tightened the belt but the noise was still there... Under further inspection I found my noise... The belt was rubbing on one of the bolts that hold the front belt guard... Where my thumb is...image.jpeg

Removed the cover to make sure the bolt was tight and it was... But with the cover off I noticed that the belt was running in a new location...
image.jpeg

It's about a 1/4" away from the motor from where it was...
And the belt is actually off the gear/pulley an 1/8" or so...
image.jpeg

So I thought I could correct it by fudging the back tire... If I get the back tire way out of whack I can get it better but not where it was running... So I measured and got the wheel alignment correct to start over and the belt went back to where it is pictured above...

FYI This is how I aligned the rear wheel...
image.jpeg
image.jpeg

Something has changed and I can't find it... All of the transmission bolts are ok and nothing looks like it has/can move but it's almost like the transmission has shifted... I don't think I stretched the belt... I think I have a larger problem... How crazy am I??? What am I missing???

Thanks guys!!!
 

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Brew

Troop Supporter
So one question? You should have a set screw (long) that adjusts the rear wheel and a set screw (short) that locks the adjustment screw in place. Do you have both on each side? If you do then your good to go. After you have it adjusted, I would put a dab of red lock tight on the set screw so it wont vibrate loose. The only reason I ask is because I worked on a friends K-9 and he was missing the set screw on one side. Don't know if the last shop that worked on his scoot forgot to install it or not, but it wasn't there. I went to Lowes and got one there.
 

Dubbs_

Member
Yeah I had all 4... Kicked one of the short ones across the shop never to be seen again... Grabbed a set off the bench and had the correct one to replace it...:whoop:
 

Brew

Troop Supporter
So if the alignment doesn't fix your issue see below comment.

So, what you just explained that sounds like a heat shield vibrating could be the vent tube inside your gas tank. A lot of us have had the weld on that tube bust loose and rattle like crazy while romping on it. There's a thread on here about it. On here it is, check it out and see if this could be the issue... http://www.bigdogbiker.com/threads/remove-vent-pipe-from-gas-tank.21485/
 

Dubbs_

Member
Thanks Brew, I'm positive the noise was the ribs of the belt rubbing on the belt guard bolt... But if it continues after I figure out how to get my belt running in the correct spot I will take a look at that...
 
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Th3InfamousI

Administrator
Staff member
Did you measure the alignment before you made the adjustment? Could have been a combination of misaligned rear tire and a little stretch. I would ride if and check it later If it moves.

Sent from my 831C using Tapatalk
 

dingo

First 50
When I changed my drive belt, I seem to recall reading that belts can be somewhat directional due to the nature of belt construction - sort of like a directional tire - if all else fails, it might be worth try reversing the belt to see if it tracks better. Keep us posted.
 

Dubbs_

Member
Did you measure the alignment before you made the adjustment? Could have been a combination of misaligned rear tire and a little stretch. I would ride if and check it later If it moves.

Sent from my 831C using Tapatalk
Yeah I was kid of thinking about riding it without the front belt guard (because the mounting bolts we're rubbing the belt) to see how the belt tracks after a ride and not just spinning the wheel with the bike off the ground...

And no... I didn't do a good measurement... I did a quick measurement before I adjusted it and it looked close enough...:oldbang:
 

Dubbs_

Member
When I changed my drive belt, I seem to recall reading that belts can be somewhat directional due to the nature of belt construction - sort of like a directional tire - if all else fails, it might be worth try reversing the belt to see if it tracks better. Keep us posted.
Yeah I read where there were 3 types of belts... One would track left, one right and one straight... It could have the wrong belt I suppose... But it was fine before the flogging... I may try flipping the belt... I doubt I can get that lucky but it would be an easy fix!!!
 

blacktopper

Active Member
My belt on my 07 K9 has run to the outside for 75,000 miles. I had Gene at Strokers look at it and He said it should run to the outside going forward and to the inside rolling backward so I quit worrying about it and rode it. Original belt still on it.
 

Dubbs_

Member
I don't know if this helps or not but I could get the belt running in the correct spot with the belt loose... But the tighter I got the belt the further it would walk away from the motor... I tightened the belt with a sixth of a turn on each adjuster and gave the tire a good spin or two and the belt would walk out further every time I moved the wheel back... And let me tell you... That belt WILL bite the heck out of the inside of your palm!!! #%?!$&@!!! Learned to pull on the tire and not the pulley/gear quickly!!!
 

Dubbs_

Member
My belt on my 07 K9 has run to the outside for 75,000 miles. I had Gene at Strokers look at it and He said it should run to the outside going forward and to the inside rolling backward so I quit worrying about it and rode it. Original belt still on it.
Thanks blacktopper, that makes me feel a little better about it... Just wish I couldn't see where it "was" riding...
 

Little-Boo

Well-Known Member
Troop Supporter
Have you checked the rear wheel bearings or even the axle to make sure it is not bent. I had a situation a long time ago that my wheel would rub on the belt and made a metal to metal screeching sound when I turned left. I rode like that for the rest of that weekend as I couldn't see anything wrong. When I got home I jacked it up on the lift and my rear wheel had a little movement enough for me to attempt to take wheel off but no luck. The bearing on the left side of the wheel had busted out and got so hot it welded the bearing race to the axle. I had to cut the axle off to get the wheel off. Check or replace the rear bearing, also check your tranny to make sure the bearing on the tranny have not gone south on you.

Carlos :whoop:
 

Dubbs_

Member
Have you checked the rear wheel bearings or even the axle to make sure it is not bent. I had a situation a long time ago that my wheel would rub on the belt and made a metal to metal screeching sound when I turned left. I rode like that for the rest of that weekend as I couldn't see anything wrong. When I got home I jacked it up on the lift and my rear wheel had a little movement enough for me to attempt to take wheel off but no luck. The bearing on the left side of the wheel had busted out and got so hot it welded the bearing race to the axle. I had to cut the axle off to get the wheel off. Check or replace the rear bearing, also check your tranny to make sure the bearing on the tranny have not gone south on you.

Carlos :whoop:
I checked the rear wheel for movement and it felt German (goodntight)... Lol Didn't check the transmission output shaft... I will tomorrow though...
 

Olde Man

Active Member
I could not keep adjust my alignment to keep my rear belt running in the proper place. It ended up being my belt drive pulley on the transmission It had worn out the splines that mate it to the transmission output shaft. Caused by running the belt too tight.
 

Dubbs_

Member
I could not keep adjust my alignment to keep my rear belt running in the proper place. It ended up being my belt drive pulley on the transmission It had worn out the splines that mate it to the transmission output shaft. Caused by running the belt too tight.
How did you end up finding that???
 

Dubbs_

Member
Well I put everything back together except the front belt guard and took the bike to lunch... Good news & bad news...
The good news is that the noise is gone!!! Bad news is that the belt is rubbing on the inside of the clutch adjustment housing...
 
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