VBB Gears jammed and now this sound
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Ossessionato
73 Rally, 74 Rally, 76 ET3, 80 P200, 63 Li125, 65 Li225 Silver Special, 86 Elite 80, 2015 HD Road Glide Special, 2011 Ural Tourist
Joined: 18 Jan 2012
Posts: 3258
Location: Oceanside/ SF
Thu May 23, 2019 4:26 pm quote
So a friends Non Vietnamese VBB that used to run fine, ended up with the clutch woodruff key jammed in the gears about a month after he changed the clutch. It must have been sitting in there a while but he came to a skidding halt. I got the motor and tore it apart to find out what it was. Rebuilt the motor with a new shift cross, seals, gaskets and fired it up. It had this bang, bang, bang noise coming out of it. Tore it all apart again. Scratched my head a bunch and here's where I'm at.

-Removed and reinstalled the old shift cross. No change in the sound
-inspected all the teeth of the gears. Nothing nicked or broken.
-noticed a small nick on the inside of third gear. He jammed in third and slid to a stop.
-inspected all the teeth on the primary drive. Can't see anything
-Inspected all the teeth on the cush drive. Dont see anything.
-Removed and reinstalled the clutch with a new woodruff key.
-Removed the clutch cover and pressure plate.
-Removed the rear tire and hub
-Removed the head, cylinder and exhaust during initial rebuild. New piston rings only.
-Kickstart cog inspected. Nothing and reinstalled. Makes the noise even if the kickstart lever is engaged.
-side loaded the crank by pushing on it from the flyside.

After all that and probably more that I forgot, it still makes this banging noise. Watch this video and you'll hear it. Its a little faster than once a second. It used to go away in neutral but now its all the time in every gear.

Anyone ever come across this one?
Molto Verboso
PX221 Malossi, O tuned PX200 and some motorbikes
Joined: 14 Jun 2017
Posts: 1461
Location: London UK
Thu May 23, 2019 7:39 pm quote
Sounds like gearbox. Does the tapping noise stop if you pull the clutch in? How about when holding in clutch and in gear?
Ossessionato
73 Rally, 74 Rally, 76 ET3, 80 P200, 63 Li125, 65 Li225 Silver Special, 86 Elite 80, 2015 HD Road Glide Special, 2011 Ural Tourist
Joined: 18 Jan 2012
Posts: 3258
Location: Oceanside/ SF
Fri Jun 21, 2019 6:34 pm quote
So the problem was definitely gears. Jack you nailed it and sorry I didnít respond. I had to leave for 3 weeks for work so the project sat. Once it was in a running stage, I ran it and squeezed the clutch and the noise went away no matter what gear it was in. It didnít have a wheel installed so I couldnít roll rear it.

Interestingly enough though, there were no broken teeth. I had 4 sets of eyes look the gear cluster and the primary and other than a small indent, nothing was broken.

The owner priced out gears and said screw it and decided to spend money on everything else (rear axle, rear seal, rear bearing, selector side axle bearing, new kickstart cog, Cush drive rebuild). Heís going to live with the clicking until something breaks or it goes away.
Hooked
2001 LML 150
Joined: 16 Jul 2017
Posts: 315
Location: Melb, Aus
Fri Jun 21, 2019 10:10 pm quote
19 secs into that video.. is that the g'box drain hole?
Ossessionato
73 Rally, 74 Rally, 76 ET3, 80 P200, 63 Li125, 65 Li225 Silver Special, 86 Elite 80, 2015 HD Road Glide Special, 2011 Ural Tourist
Joined: 18 Jan 2012
Posts: 3258
Location: Oceanside/ SF
Fri Jun 21, 2019 10:14 pm quote
Yes
Hooked
Bodgerific 150 Super, 50s in progress
Joined: 18 Aug 2016
Posts: 256
Location: Melbourne, Way Downunder
Fri Jun 21, 2019 10:17 pm quote
Reckon that's it

Screen Shot 2019-06-22 at 4.15.36 pm.png

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