Custom Exhaust for Gumby

[Mad RS]

Now I have pulled all the fairings off the Gumby (Known as B2) I have started looking around at what I want to customise. One of the big things I want is a customised exhaust. Ever since picking the bike up I have loved the look of the Bozbros Moira exhaust but they don't make them anymore and I think it would be just too loud for riding. What I have been thinking about is some how keeping the stock catalytic converters and making the shorty exit where the red dot is....

Moira exhaust.jpg (44.37 KiB) Viewed 1024 times

It still would be loud but would it muffle the noise enough to be ridable?? I know it won't be legal but what are your thoughts??

[hoffy]

Ask Glen about wher he got his HP Corse gumby pipe... Its radical!

[Mad RS]

Who Glen???

[timmyrocks]

Glen,,,,,, Glen

seriously his ksrc login is Glen

[hoffy]

Glen as in 'glen'

[Wattie]

there is a reason the stock pipes are up the back.

Thats where they make the best power. the length is better suited to the engines characteristics.

[hoffy]

I think dave calls it 'tuned length'

[zxsixr03]

Add a short pipe and u will loose all mid range

Hours and hours of R&D go into what it is and how it is, don't change it, replace it with something fancy but don't change the design...

[Mad RS]

Can a lack of mid range be tuned out?? I'm looking at adding a PCV with an auto tuner. Is this

I was mucking around just before and got to thinking that I may be able to make a simple silencer to replace the 'cats' without destroying the standard system (so if it all goes arse up I can still fit a set slip ons and have it tuned with the auto tuner). Maybe by adding some restriction in the pipe it will increase the back pressure to somewhere near stock or a little less. I have until the end of September to do everything that I want. Anyone recomend a custom motorcycle exhaust shop that I should talk to?? I'll get some advise from a tuning shop as well.

The design I have thought of will have a replacable center tube so I can do some R&D on different packing material, differnet perforations and different baffleing. Just a pipe dream at the moment (pun intended)

[zxsixr03]

Short answer NO

Buy a cheapish slip on from the US, Leo Vince go for around $300 get your PCV if it runs on your year model with auto tune and it will be sweet..
Seriously don't go attempting a home made exhaust it doesn't work

[Wattie]

Fueling won't help it.

It's cam grinds, firing order, timing and port sizing that needs to be tuned for a short pipe.

[Wattie]

for an example...

side exit exhausts are all that they seem...