Exhaust question
rm0rgan - 30/9/15 at 07:16 PM
Hello. I've replaced the bike can I had on my MK Indy with a Wunoff exhaust can and have a question...
As the new can is longer by a few inches do I need to cut the excess exhaust pipe down so it just enters the new exhaust chamber or can I simply slide
the excess into the exhaust.
Description
For now I've slid the excess in and it seems fine and revs ok etc - it's quite a bit quieter and deeper in tone than the bike can but
wondered if I should cut the pipe down in case I'm restricting it at all.
Thoughts appreciated :-)
[Edited on 30/9/15 by rm0rgan]
[Edited on 30/9/15 by rm0rgan]
[Edited on 30/9/15 by rm0rgan]
bi22le - 30/9/15 at 09:36 PM
A quick calculation assuming you have a 50mm dia exhaust going towards the silencer, and that all wall thicknesses are 1mm says that the reduction in
area is around 8%.
It may rev fine but its when the engine is under strain you will notice the difference. Give it a whirl and see what happens. I know that most
silences slide over the collector tube.
snapper - 1/10/15 at 05:44 AM
The only thing it will do is increase the noise as you will be blocking some of the perforated price inside the can
907 - 1/10/15 at 06:26 AM
It's a bit like buying an eight bedroom mansion and only living in two of the rooms.
Paul: ^^^ What's a "perforated price inside a can"? 
Just wondered if I should be fitting them. 
Paul G
rm0rgan - 1/10/15 at 06:47 AM
quote:
Originally posted by bi22le
A quick calculation assuming you have a 50mm dia exhaust going towards the silencer, and that all wall thicknesses are 1mm says that the reduction in
area is around 8%.
It may rev fine but its when the engine is under strain you will notice the difference. Give it a whirl and see what happens. I know that most
silences slide over the collector tube.
Thanks. Bi22ie I did have a look at other people's silencers and it seems hit and miss as to whether they slid over or under the collector and in
some ways it makes sense for it slide in as the design looks like it's wider at the start so as to 'receive' the pipe and then the
bracket clamps it down to seal it. It's also how it was on the car when I bought it and the same set up as was on my other cars.
That said, it's the excess I'm most interested in as I thought like 907 suggests, would I be losing some noise reduction (but I actually
find it quieter than what I had previously so either I'm already deaf or the bike can was madly loud which it did feel a tad too loud to me).
I'll give it a bit of time to see whether I notice any change in performance. A quick blast yesterday didn't seem to register any drop in
performance but I only went for a quick blast.
I might cut the excess pipe off but leave it mounted the way it is as just to make it easier to remove when I want to repack it.
