quite interesting..

http://uk.youtube.com/watch?v=EeppBwzdgBI&...feature=related

Yip, he put the worn old Bing 84 back on and it's running like a heap of ****!

Big John

I think it would have been good to take the bend out of the top frame tube while it was apart.

Interesting that he seems to have sprayed the plastic tank, assume that won't stick for long.

i suppose he was trying to get it to run as smooth as this. http://uk.youtube.com/watch?v=tIJmQGmSoQc&...feature=related

as BJ has intimated though the carby MAY be at fault..

Exhaust needs repacking by sound of it.

Exhaust needs repacking by sound of it.

Yep, makes a heck of a difference to a Sherpa, once it has either blown its packing out or clogged up the perforated tube the performance is badly affected and can give symptoms similar to a worn carb. My Sherpa wouldn't rev out at all and wasn't smooth off idle, even with a new Mikuni on it. I tried several carbs, including one from a bike that ran well before succumbing to the inevitable and splitting open the silencers to clean and repack them. The middle one had no packing left at all, the rear was pretty clogged. Difference was very noticeable when done.

Did you split the clubfoot? Is that then a welding job to put back together?

Yes, as is the middle box. It's a ****ty job but needs to be done. The Sherpa should purr quieltly if the exhaust is in good order, if it doesn't, chances are a repack is required.

On the clubfoot the perforated tube only goes as far as where the silencer passes behind the shock. From there onwards and into the clubfoot itself there are a series of baffles and there is no point splitting the silencer open in this area unless the baffles have come loose. If you shake the silencer and can hear movement inside it doesn't necessarily mean baffles are loose. The perforated tube could have come loose or it could be big lumps of carbon welded wadding rattling around the tube.

I split mine by grinding down the flanges on either side where it is roll or spot welded until you can see the split appear between the two sides. On the inside (tyre facing) side of the silencer I cut accross at the top and the bottom and lifted the section off to reveal the inside. The tube was that badly clogged I also had to cut that through at each end and remove it to clean it up. After removing any carbon/old wadding from the inside I then placed a bunch of packing (silent sport wool) in the silencer, replaced the tube on top of that and tacked it back in. I then replaced the removed section and tack welded it back on but on one side only. This let me lever it open like a door using the tack welds as hinges if you see what I mean. I then finished of putting more pcking in before 'closing the door' and welding it back up again. I did the same for the middle box. Bike ran so much better after that.

Where to cut it exactly is difficult to explain and I can't post pictures. If you got hold of a scrap used one from ebay or somewhere you could cut that open and then you could see where to cut your own, that's what I did, tried it first on one that didn't matter.