GEBE exhaust / muffler mod

[bamabikeguy]

Jemma-

To edit, go to the top of the thread, post #1, (and the only one that can edit TITLE), add some specific words, and save. Whoola.

Note I put a blue MB.edit, that is kind of a MBtradition, meaning you found the answer, answered your own question, or made a possibly bogus claim in that post. Usually we leave the bogus part intact, the "blue" signifies we realized our error.

If you make a bogus claim, and don't correct it, a moddy may put a "red" MB.edit.

Tools-mimimum to "framemount" a hacksaw, drill and 2 sizes of bits. Don't bother with all my doo-dads, I'm trying to streamline quick installations.

Curved handlebars, with foam grips and "cruise control" to free up thumb on the throttle, for wide open 10-20 minute spurts, is the key to preventing MB.elbow.

 

[JemmaUK]

Exhaust modification part 2.

Hey,

I was relaxing this afternoon and got to thinking... I wonder if the size at the end of the exhaust modification (see picture) would fit the end of one of those beer cans I kept ....

So I had a look. It fit perfectly with just a small gap at the exhaust end that was easily plugged with Polymorph (meltable moldable plastic)

So I now have a jerrybuild muffler at the end of the exhaust - I'll just need to test it..

Pics attached.

Jemma xx

 

[gone_fishin]

no WAY! does that work ok?

hey guys, to everyone: the new board comes with some new procedure: you have one full day to edit your content...after that, you are free to PM the moderator to request changes...talking about it in the thread is not always gonna catch our eye, we can barely just barely read all the new content even when split up into zones. pitch in wherever and whenever you can, pm the forum moddy and help us keep things neat and tidy. thank you.

jemma...i'd love to hear what that sounds like.

 

[BTB Wild]

Yes.....PLEASE report back. I hear the theme to 'Sanford and Son' playing in my head and an image of you and the cops standing beside your bike administering a sobriety test.

 

[Alaskavan]

Do they still make Carling?

 

[JemmaUK]

Do they still make Carling?

lol, yes they do - it might be that they dont export it.

As to the muffler it seems to work as a proof of product as it were. The trouble is that I need to make a few changes because the rubber sheared at the top mount because of vibration along the edge of the cable tie.

I have made a couple of changes to the muffler itself. I've made what is basically a double length single baffle muffler with flare. Its amazing what you can do with a pair of scissors, pliers and sellotape (and yes, I will use heavy duty tape when I can get hold of some).

It does seem to make a difference, but until I use it on the road I wont be able to tell...

I am planning to mount the muffler horizontally on the engine side underneath the engine using the upright of the GEBE mount and link to the engine using silicone exhaust pipe..

Jemma xx

 

[Alaskavan]

Jemma,
Don't use duct tape. It's good for a quick, temporary fix, but it can't stand exposure to the elements or changes in temperature. It is no good for ducts. From Wikipedia: "The name "duct tape" came from its use on heating and air conditioning ducts, a purpose for which it, ironically, has been deemed ineffective."
That said, I wish I had an alternative to recommend.
On my bike (43cc Mitsu, Staton friction drive), I attached copper pipe and used an improvised bracket and JB Weld. So far it seems to require regular attention, but it does make a difference in sound level. Over time I hope to resolve the problem of it shaking loose.

 

[JemmaUK]

New Pics

 

[bamabikeguy]

HIVE,

Why don't you post those pix you deleted on your experiment?

I would try to describe to Jemma how you drilled that hole in the plastic engine cover, but your pix would tell a thousand words.

That way this thread can be the place to look for exhaust questions, INCLUDING (one day) step by step instructions in scraping away carbon buildup on the cylinder walls, which is another source of hiccuping after about 1,500 miles or so.

 

[JemmaUK]

UPDATE:

I have secured the muffler as shown above to the metal protection framing around the fuel tank. I left the elastic support around it (see there are uses for spare hair bands) as a just in case. Attachment method is two large cable ties.

I have also slowed down the idle on the motor - it seemed that the backpressure was causing the engine to run faster than it otherwise would at idle - and it does sound better at a slow idle.

I would get at this point about 30-something miles per tankful, does this sound about right - and is a slight blue haze on first starting (from cold) normal?

UPDATE: Just took Anita out for a run - she purrs - literally - with the throttle off the engine is very very quiet and sounds like a much larger bike. I dont know the effect the adjustment of the idle will have on cold starting...

Jemma