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Rebuilding after a sieze and i can't seem to seal the connection between the U bend and exhaust box. The camp just will not seal 100%, even with some 3 bond and i can see small leak of exhaust fumes. Is this dangerous or will it effect the jetting and do i need to ensure a 100% seal? Thanks for the input. -- G.

Yes, you do need to fix it. Your exhaust is not functioning as it should. It sounds like when the silencer is fitted, it is pulling at the u-bend. Usually, the remedy is to take a cylindrical file or dremel to where the silencer fits to the engine casing.

What cylinder do you have?

Storkfoot wrote:Yes, you do need to fix it. Your exhaust is not functioning as it should. It sounds like when the silencer is fitted, it is pulling at the u-bend. Usually, the remedy is to take a cylindrical file or dremel to where the silencer fits to the engine casing.

What cylinder do you have?

Hi -- it's a standard 200 barrel .... i'll get into it and fettle a bit -- G

I don’t see where it fits the body of the block would cause this, ?

L111amo wrote:I don’t see where it fits the body of the block would cause this, ?

I am not saying that the engine casing is at fault.

If either the silencer or the ubend, or both, have not been made to correct tolerances, they won’t marry together correctly. You can’t adjust the ubend, without great difficulty, but you can adjust the silencer fit to the engine casing. It’s not ideal but you haven’t got much choice, other than sending it back.

I have an AF 42mm Clubman fitted to a standard Jet 200 barrel. It only needed the slightest of adjustment to the silencer to be a very good fit. But, that was probably more by luck than by design.

Doesn’t say it’s a new exhaust

… You can’t adjust the ubend, without great difficulty, but you can adjust the silencer fit to the engine casing. It’s not ideal but you haven’t got much choice, other than sending it back….

On reflection, if you assess that the silencer would need major “adjustment,” you may need to look at adjusting the ubend. If you adjust the slots where it attaches to the cylinder, you need to be very careful that you don’t do too much so that you then get an air leak there. If you bend the pipe slightly, you need a means to get the bend to red hot.

Good luck with whatever you decide.

Generally some decent exhaust paste should fill slight gaps at the joint, just let it go off before starting it up or it will blow out

L111amo wrote:Generally some decent exhaust paste should fill slight gaps at the joint, just let it go off before starting it up or it will blow out

Thanks for all the input guys, it's not a new pipe, it's a bend & box off another bike. I'll try a blend of filing out the tailpipe hole and the chain casing hole to make it a slip on/in fit and get the paste into it & see what happens. If all fails then a new pipe. Main question was does this need fixed and the resounding answer is yes it does, so onwards.

Thanks again & I'll keep you posted - G