NC30 Exhaust System sealing

[rossman_999]

Im am having difficulty getting the rear left hand head to downpipe to seal.

Im now on my 3rd new exhaust seal and Ive checked that there is not an old copper washer in the port!

Ive tried everything, but I just cant get it to seal -any suggestions?

[Old Painless]

The exhaust itself may be leaky due to a warp or dint in the metal. You could refinish the end of the pipe with a grinder and then by hand file if its not square and flat. Depends if thats your problem or not, as long as everything is spotlessly clean it should all go back together properly, carbon not packed in the exhaust outlet port ?

[rossman_999]

The system uses a collar and plate arrangement and it is flush. Unfortunately its the rear left which is almost totally inaccessible on the NC30 and you need to strip down half the bike to gain access to it!

Because of the angle that the downpipe are at, you cant tighten the collar up until the downpipe is fitted. I have not used any exhaust sealant.

Help I am at my wits end!

[micpec]

The system uses a collar and plate arrangement and it is flush. Unfortunately its the rear left which is almost totally inaccessible on the NC30 and you need to strip down half the bike to gain access to it!

Because of the angle that the downpipe are at, you cant tighten the collar up until the downpipe is fitted. I have not used any exhaust sealant.

Help I am at my wits end!

I've done this on my NC35 earlier this week due to a broken stud on the manifold that holds the rear left down pipes.
To get the manifold out of the back of the V-engine, I had to strip half the rear end.

Do you have a suitable bike stand (abba stand?). You may find it easier to strip the rear undertray and also the rear suspension unit so you have a bit more play to manouvre your hands and tools. The rear manifold is a tight fit on the rear cylinders. Use good/new copper exhaust seals. First get it fit right, slightly fit one by one the nuts on the studs and when all it clear, tight them to specific torque as per manual. Overtight them may result in bad/broken studs!

[rossman_999]

I use a bikelift which is a great bit of kit so you are working at a decent height. Ive found by removing the battery, you can with care rotate the rear subframe (ive emptied the expansion tank and will change the brake fluid) and using a 1/4 drive with a UJ and 2 x wobbily bits you can gain access without removing the rear shock. Importantly you can start the bike to test it without taking an hour to reassemble everything

As its a full system it doesn't use the rear exhaust manifold, ive used fresh gaskets each time but I am surprised how little they are compressing compared to the ones I removed.

Arg!

[micpec]

I use a bikelift which is a great bit of kit so you are working at a decent height. Ive found by removing the battery, you can with care rotate the rear subframe (ive emptied the expansion tank and will change the brake fluid) and using a 1/4 drive with a UJ and 2 x wobbily bits you can gain access without removing the rear shock. Importantly you can start the bike to test it without taking an hour to reassemble everything

As its a full system it doesn't use the rear exhaust manifold, ive used fresh gaskets each time but I am surprised how little they are compressing compared to the ones I removed.

Arg!

Is it a full system that comprises of usage with these sort of rear manifold collars and clamps (shown samples are from tyga)...??

[rossman_999]

[quote="micpec

Is it a full system that comprises of usage with these sort of rear manifold collars and clamps (shown samples are from tyga)...??][/quote]

It is indeed, they look identical to the tyga but there is no markings on any of the downpipes

[LUCAS]

I have used some high temperature sealant before on my NC29 and motocross bike and it's worked brilliantly. Just make sure the surfaces are clean and jobs a goodun :)

[Polisher]

Use a bead of clear silicone around it. That will cure the problem instantly

[Old Painless]

Are you using the correct amount of torque on the fixing nuts ?

If so and its still leaking try going a 1/8th turn tighter.