MOPED ARMY

that simonini thing with the sliding joint was cool, I almost bought one, alas they are gone now

Yeah that simonini pipe was pretty cool, Im not sure if it actually slid or just flexed within a rubber bushing like the vlx exhaust does.

The vlx exhaust style coupling was my first idea, but i came up with a few flaws that i would like to work around.

The bushing that is used to keep the pipe sealed leaves a ledge that in a expansion chamber im afraid would reflect part of the reverse pressure wave back, making the pipe less efficient. also the bushing on my vlx is leaking bad, but it could be because its from 1978...

there a quick drawing of my concern.

I think the ultimate moby pipe would use a flexing joint at the flange, a rotating rear mount, and a sliding tube at the header before the chamber. this way when the motor variates it shortens the header making the power band narrower.

keep in mind im not a pipe builder, and all my ideas could be competly wrong, but im pump to try working out a awesome winter pipe project.

heres a pic of the flexible exhaust tubing.

yeah i've been thinking about this awhile myself. i think by repositioning the joint about 8 inches down the pipe, you could make it a gentler radius to bend, and you could use a braided flex coupler. the only problem would be the vibrations tearing up the braiding. we use something similar to the flex coupler on pumps at the hydraulics lab i work in and they take the high pressure and vibrations well.

looks like a disaster to me.

Ya know, you can order a single ball joint, along with most anything else still being made for the Moby's over at www.la-becanerie.com

It's a little pricey, but the Euro has not been this weak against the dollar in a LONG time so stock up now on your moby performance parts! It's 36 Euro for your basic package sent internationally. The last time I ordered from them, once the order was processed and boxed, it took 4 days to go from the outskirts of Paris to my door.

Nothing is going to touch the real thing.

ah, well that's a good find right there isnt it!.

Maybe ill get one of the real joints, and spend the R&D time working on the sliding joint. Calculator here i come....

And yes, this most likely will result in a disaster, but i have to do something to keep me sane this winter.

no, the mbk51 is the av10, but you can use most of the exhaust parts interchangeably i believe.

https://www.treatland.tv/peugeot-header-exhaust-flange-flexi-mount-p/peugeot-exhaust-flange-stack.htm

The flex exhause pipe does not do well if flexed often, it is bendable so a DIY person can route a fixed exhause on their vehicle without a pipe bender. It is spiraled steel with a channel lock on the spiral so it can come apart with no warning.

Melvin's bike was fast and solid.

I love this design.

(edited)

You could just weld brace at a right angle all the way around the plate to stop it from bending. I did that to my hobbit exhaust mount.

Makes it almost unbendable

Chris from Tomahawk just welded up a bidalot exhuast with a push spring system... this looks like the best long term solution. check it out on his site.