Author Topic: fourth time lucky (Read 3381 times)

neil 126 · « **on:** June 19, 2006, 11:14:54 PM »

i have picked up my fourth exhaust for my bis, the last three have all split after doing no more than 2000 miles, each time the auto factor has replaced it under warranty.
i have checked the mountings in the cylinder head they all seem fine, no stripped threads.
i will be fitting shims where there are gaps between exhaust and mounting brackets so as not to cause stress, new lock washers, threadlock and new manifold studs and nuts.
am i missing anything?
i dont want to have to take this one back, the guy is getting fed up with me.
p.s. bis13 is that sporty exaust still going well? if this one of mine still fails i'm going to get something simillar.

126dave · « **Reply #1 on:** June 20, 2006, 06:20:18 PM »

neil,i think you have it covered,how do you fit it tho?......not trying to tell what to do but,i always bolt up to head/manifolds, then shim the brackets off the block(if needed) so they dont load the exhaust........i guess you are doing this already,i cannot think of anything else tho,so its over to the other guys.............

Chris Lakin · « **Reply #2 on:** June 20, 2006, 06:55:46 PM »

this is odd, laugh at me here but is it not down to a poor quality exhaust?
its not the hardest thing in the world to do, and by the sound of it Neil you sound clued up, im just thinking could it be this company you are getting exhausts from?

mine have always bolted on fine without probs.

regards

Chris

Darrell · « **Reply #3 on:** June 21, 2006, 11:10:22 PM »

I had a similar problem with the exhaust on my old XS1100 motorbike.

I would weld the exhaust up and fit the exhaust, being as careful as possible to make sure there was little stress but it was impossible as the engine is rubber mounted on the XS and the rear hangers are rubber.

Of course the engine being heavier moves quite a bit and the rubber hangers at the back didn't.

In the end a new exhaust system solved the problem and havn't had the hint of an exhaust leak since!

I'd say something is resinating/moving.

If all is tight etc and no stresses in the mounting department it has to be the pipe is resinating which will cause it to crack time and time again!

I comntmplated placing that matting they have in some silencers inside the old XS silencer to try stop the resinating but never got around to it.

It was amazing, you could feel the pipe resinating if you put your boot on it (coldish pipe of course).

I have done over 2000 miles in my BIS now without the hint of an problem with the exhaust, and I found out ont of the mounting bolts is missing!

I shall be on to it to replace it however this emphasise the diference between exhausts.

I doubt I have come-up with any genius in the tuning department thus is must be your pipe?

bis13 · « **Reply #4 on:** June 22, 2006, 10:23:48 PM »

sorry chaps but i have already brokem my sports box! its broke in the same place as my standard system at the connection of downpipe and manifold lug(?) i will get them both welded up and try again i cant see why they are breaking as i am not stressing them up by forcing the brackets which is a normal error. either way i dont realy care much as its noisy anyway and i am deaf....

neil 126 · « **Reply #5 on:** June 26, 2006, 07:21:40 PM »

thanks guys, i have to replace the cylinder head gasket, then will be ftting the exhaust and turning the engine over this weekend, hopefuly, for the first time in months. who would have thought a bit of welding and generall tidy up would take so long? i wont be driving it as i still need some bits from our pollish friend.
re your question about the suplier chris, its a reputable motor factors, the exhaust is new, ie not been sat for years o the shelf, and made in italy.