I'm a new guy here but I was wondering


just for kicks

Has anyone done a custom frame with the exhaust built into the frame somewhere?

Just a crazy thought most likely brought on from all the cool/custom bikes I've seen here.(truly amazing work)

Anyway in about 2 weeks I should have my kit and then I have to decide on what to put it on.
As a matter of fact I was talking to a buddy of mine about this very thing today. Seems like it would work as long as your head pipe wa flexible.

Welcome to the group!

yeah! like one of those dryer hoses that is a coily thing that bends. I saw one of those on ebay. Go look :cool: tell us what you find
...i'm a former auto-exhaust mechanic...i can't locate it at the moment, but there is a stainless-steel flex tube used in universal pollution repair kits (with nifty crimp clamps) that comes in 5/8" & 3/4" that would be perfect, imo. maybe other sizes too.

our local IMCO distributor had it in the 80's when aftermarket converters & airtubes & checkvalves were new science, but i just can't seem to dig up any info. i'll keep looking.
Thanks for the welcome and I'll try to get into the I.Y.L this weekend.

I was thinking more about this at work today (work gets boring) and it seems like it would take some work but should be doable.
I wonder how much it would heat up that section of the frame.

Anyway I cant hardly wait for my kit to get here and I'm sure I'll just install it like it should be on my old mountain bike until I come up with something better.

I was thinking just cool these bikes look over any moped or scooter.
I hated riding my brothers mopeds (a grown man on a moped just never looks right to me) but I think this engine on my mountian bike will be very nice.
You could connect it with a section of high temp silicone tubing available at most hobby shops. Used for connecting the exhaust header to the expasion chamber of model planes.

My rack mount uses an after muffler with a black rubber hose (see the Gallery) it doesn't get too hot once it's that far down the line.
Just a guess, but I would think the paint would tend to crack or flake off wherever the exaust entered the frame. I bet it would be alot quieter tho.
Welcome to the board... :)

It would be possible but I foresee two problems that would need dealing with...

The first is backpressure, if the exhaust 'line' is too long then it might throttle the engine power.

The second is the strength of the frame might be compromised by both the hole and the heat of the exhaust fumes (only a consideration if the port to the frame is extremely close to the engine port)

However - it would be almost whisper quiet - and indeed its a method used in some of the goped machines for that very reason...

I do have a thought though - some of the people on here make their own frames - given that this is the case why not make a tuned pipe part of the frame itself - which would make the bike very clean visually and help with power as well as running quiet...

My personal opinion is that too much quiet for the sake of it can make a MB more dangerous rather than less - in the animal kingdom its the predator that you cant see/hear coming that eats you... in the same way there seem to be alot of humans that dont see danger unless they can hear it too... *listens to the sound of the gene pool getting slowly shallower* ... I have been buzzing round my town for months and not gotten a peep out of the police...

PS: for all who asked, my bike wasnt covered for being outside my home!! thats $1400 or so down the drain + $120 for **** insurance :.(

Jemma xx
Interesting idea!...I would think that the down tube would be the perfect place to build in a tuned pipe/expansion chambered exhaust.