Show us your Pipe!

[Greg58]

I finally got to work on a pipe, lve been doing a little reading on the best length of the head pipe for bottom end torque. What I came up with is about 16 inches, 3/4 emt bent as tight as I could get it with a conduit bender. I made the chamber section out of a conveyor roller and salvage parts. I'll post pictures when I get it all dressed up, now it in untouched form while testing. Its good on the bottom end and even better on the top.

 

[grizadams]

This is what I did today, not quite done but close. It's just a 35.00 dollar exhaust I bought off of ebay.

 

[GearNut]

That looks pretty good, griz!
I hope that you won't need to wear Nomex pants with it though.
Are you going to keep it as it is, add a heat shield, or wrap it with exhaust header wrap?

 

[grizadams]

I'm thinking heat shield.

 

[Greg58]

I was wondering about certain parts of the anatomy getting hot sitting right over the chamber. Looks like a good pipe, how does it run?

 

[grizadams]

I've got a CDI or a magnito problem so it's not running right now. I will find out about heat and then I will address if it's a problem.

 

[Greg58]

I still haven't had a chance to clean up the welds but thought i show what i have so far, everything was scrap except the emt used for the head pipe.

http://motorbicycling.com/album.php?albumid=259&pictureid=4883

 

[frogbiscuit]

EMT conduit. Stock exhaust cap fell off so I welded a 2" washer and a piece of pipe on the end.

 

[borntofli]

BGF expansion chamber

Just put this on today.... Had to bend the pipe just a little to clear the peddles...
I'm still working on the bracing....

Anyone have an easy idea for a leg guard??

Have only rode it for about 2 miles, but it gets the exhaust noise behind me, so all I hear now is the noisy engine....I think it is quieter than stock...

It seems to run a bit smoother and a small increase in low end torque....

I dont know how top end is, I generally only run to half or 3/4 throttle....

This pipe was 50$ shipped......

 

[KCvale]

Yes, wear long pants ;-}

 

[moonerdizzle]

If looks don't matter aluminum foil makes a good heat wrap.

 

[Harold_B]

I always wear long pants when I ride. Burned my leg on the jug fins. Once was enough. Anyway, back on topic! Had a SBP expansion chamber and muffler on the bike but just could not get the clearance I wanted to the pedals and kickstand so off it came. I now have one inch copper tubing bent so that the cheap muffler that comes with a kit could be hacked off and used. Aluminum bar was bent, drilled and tapped for clamps and the pipe wrapped in header wrap. That black stuff is filthy to work with.

I don't have a tubing bender so I used my knee, or my foot, or whatever was at hand to shape the pipe. For the sharp bends I put the pipe in a bench vise between two pieces of hard maple to keep it from collapsing. Worked well for the most part although at one point I was making a bend to the short end where the pipe meets the jug with the long end sticking up and the grip on the boards let go. Pipe smacked me right in the forehead. I couldn't help but laugh.

 

[borntofli]

I solved the leg burning issue.... Dont touch the pipe......

I live in s. texas and dont own pants......I dont own a pair of shoes either.....Flip flops...... No flintstone stops for me.....

 

[Harold_B]

Flip flops in Texas?

 

[KCvale]

I always wear long pants when I ride. Burned my leg on the jug fins. Once was enough. Anyway, back on topic! Had a SBP expansion chamber and muffler on the bike but just could not get the clearance I wanted to the pedals and kickstand so off it came.

The beauty of the SBP pipe is you can plumb it however you want like I did with Bad Mojo.

Borntofli
I solved the leg burning issue.... Don't touch the pipe......

I live in s. texas and dont own pants......I dont own a pair of shoes either.....Flip flops...... No flintstone stops for me.....

Hahaha, good one, riding in flip-flops.

Though long ago a friend (Drew Durvoy) and I actually rode our real motorcycles late at night butt ass naked but we still wore shoes. Ya, the cops came by after we were home (we caused quite stir in our apartment complex) but the bikes were inside and they just said 'No more of that OK?' We polity agreed but it's amazing we both lived considering the stupid things we did on that ride but that's another story ;-}

Seriously though, here in Phoenix I don't wear long pants until winter but I ALWAYS wear real shoes to ride but so many people here just wear flip-flops I have have gotten into the habit of telling anyone coming to the shop to put real shoes on or they can't ride.

Riding a motorized bike in flip-flops, hahaha, good one.

 

[Harold_B]

"...beauty of the SBP pipe is you can plumb it however you want like I did with Bad Mojo." True, to an extent. The pipe from the exhaust port to the chamber is supposed to be a certain length depending on a bunch of calculations that I'm not likely to bother with. I just tried to keep it close to the pipe length supplied by SBP. Between clearing the pedals, clearing the standard, and making so that it did not point at a fuel line or my crotch I had to compromise something (and the last two on the list were not going to be compromised). The 1903 has some pretty fat tires as well making it so that the engine is offset a bit. I know a few with welding skills have made the Felts / SBP chamber work and look great but that wasn't me!

 

[pocdragon]

sounds real good 12" header lotsa torque

 

[scotto-]

Re: BGF expansion chamber

Asbestos pants perhaps.

Just put this on today.... Had to bend the pipe just a little to clear the peddles...
I'm still working on the bracing....

Anyone have an easy idea for a leg guard??

Have only rode it for about 2 miles, but it gets the exhaust noise behind me, so all I hear now is the noisy engine....I think it is quieter than stock...

It seems to run a bit smoother and a small increase in low end torque....

I dont know how top end is, I generally only run to half or 3/4 throttle....

This pipe was 50$ shipped......

 

[klapool]

My 13 year old son wanted dual exhaust on his bike....

We came up with this...

pretty cool to see dual shots of smoke shooting out!!!

 

[MeniacleMechanic]

I just fabricated up this pipe today.
Messed with it all night. Before i put the pipe on today, i went to run errands this morning, and having 850 miles in a chinabay engine, low compression, couldnt get above 30 all day.

Making this expansion chamber made my acceleration 40% faster and top speed 20%. Huge difference. Pullin 35-37 on flat and uphill torque is much better.

its not finished yet tho. gonna grind all the welds down, sandblast and powdercoat it in high temp black.