Sports Mufflers

[vanzen]

...
I agree, factory specs are the best... for everyday use. It was how the bike was designed.

40 some years ago, BMW designed a well engineered general purpose MC, the Type-247.
Since that time, it has been my goal to change the program to suit my peculiar needs ...
Simply put, to mess with about every detail that the factory determined would be the best course of action
to provide a MC that would appeal to the largest common denominator as a marketable product.
Factory specs cater to that market, but the principles of physics will yield to no one's desire.
Messing with stuff might be the best of it ... But then, I am funny that way, such as it is.

[George Ryals]

Some have discovered that straight pipes on a street bike make it very difficult it have a rideable motorcycle from idle to cruising speed. Rather than adding baffles, it is possible to make the engine tunable and rideable by simply putting a 1/4" bolt through the straight pipe a couple of inches from the end. The theory is that this simple solution sends a pulse back up the pipe to the exhaust port. Fine tuning is finding the distance from the exhaust port for the bolt according to the intended usage of the bike.

[boxertwinjeff]

Some have discovered that straight pipes on a street bike make it very difficult it have a rideable motorcycle from idle to cruising speed. Rather than adding baffles, it is possible to make the engine tunable and rideable by simply putting a 1/4" bolt through the straight pipe a couple of inches from the end. The theory is that this simple solution sends a pulse back up the pipe to the exhaust port. Fine tuning is finding the distance from the exhaust port for the bolt according to the intended usage of the bike.

George, I take it your talking of the bolt, for instance on the end of the Hoskes
I'm waiting on, that allows removing of the Baffles yes?

[George Ryals]

If the Hoshes have a diameter reduction at the end it will send a pulse back to the exhaust port. I'm talking about straight pipes not mufflers with the baffles removed.

[vanzen]

According to Dr. Curve,
What works for air-head RR,
Megaphone specs: 6º taper, 2" reverse at 45º, outlet 50% of inlet diameter.

Team Incomplete built an excellent 2-into-1 engineered specifically for the TI boxer engine
using specs provided by Craig Hanson (Hanson Racing Technology).
The design has been much copied ...
While in NY a few years back, I had the opportunity to measure the TI bike exhaust system:
Primary 29", Y 3.25", collector 18", Universal (& tunable) Supertrapp 17.5"

[r90s]

That brazed-in rod at the exit of the Hoske muffler is a wave splitter. It parts the exiting pulse from the exhaust system for better extraction action.




You can get exhaust cones made to your specs - here are some made for my next project, from Apollo Cone at
http://www.akama.com/company/Apollo_Con ... 47037.html:




Hanson Racing calcualtes the lengths of headers and intermediate pipe based on your engine build.
http://www.eurospares.com/hrt.htm


Unless you duplicated Gregor's engine, I'm afraid your dimensions won't give optimum results. Craig calculated my runs, sent me a kit of tubing, and built a muffler for me with a special angle cut for ease in changing out the wheel:




Cheers,
Jon-Lars

[vanzen]

While in NY and talking to Gregor Halenda, he told me of an MC built to replicate the TI Boxer.
His thought, if not his words, ' I haven't decided whether to be flattered or upset.'
I will think that he was "flattered" ... if not compensated.

[r90s]

Let's make it clear that you aren't referring to my red R80G/S, right?

Jon-Lars

[r90s]

I got my answer from Gregor; thanks anyway, Vanzen.

He was talking about a duplicate built in Germany. As I said in this interview by Linda Wilsmore, my inspiration was the Dunstall catalog I pored over in the early '70's.

To see the images below in full size, right click on the picture and then pick on "view image".






An aluminum tank and 2 into 1 exhaust does not make my bike a copy of Gregor's fabulous machine.

Cheers,

Jon-Lars

[mattcfish]

According to Dr. Curve,
What works for air-head RR,
Megaphone specs: 6º taper, 2" reverse at 45º, outlet 50% of inlet diameter.

Team Incomplete built an excellent 2-into-1 engineered specifically for the TI boxer engine
using specs provided by Craig Hanson (Hanson Racing Technology).
The design has been much copied ...
While in NY a few years back, I had the opportunity to measure the TI bike exhaust system:
Primary 29", Y 3.25", collector 18", Universal (& tunable) Supertrapp 17.5"

Vanzen, Do you have a photo of that 2 into 1 exhaust system?