Introduction

[Ricks]

The 2 long tailpipe model was not introduced until the automatic era started.  I've read that the 1949 Model K came with either  the front stubby canister or one like the earlier style, curved head pipe with muffler attached to left side of bike.

[Dominic DiMarko]

This may be a dumb question, but since it's a either/or proposition, would there be any engine performance difference between the longer pipe and the stubby one?

[pd]

I doubt that there would be much difference in performance , if any , as the mufflers are likely the same .

If there was an expansion chamber employed , that would definitely add a level of performance .

[Mike Sal]

Thats a good question.  I know that back in my dirt bike days, having a tuned exhaust system made a big difference in the way a 2 stroke ran.  With our older long stroke 2 cycle motors, I don't know if the rules are the same.

In wollards book, he talks about how the bikes with 2 long pipes ran better when when pipe was plugged and the other had a restricter in it.  (although my pipes are open on the ends).

Many years ago I worked for AMF wheeled goods (the little red tricycles you had when you were a kid) & we made mopeds in the 70's.  We had 2 different horsepower models.  The only difference between the 2 were the size of the intake manifold and the muffler.
Mike Sal  

[admin]

Wayne tried closing off one of the pipes and he said there was no discernible difference.  I meant to cap one of my pipes last summer as a test, but, alas, I forgot.

[Mike Sal]

Achtung alles Simplex Bastler und Sammler!!! 
We've been getting a lot of new people signed up on the site lately!!!!  WELCOME to each of you.  Please send us a little note about yourselves & your bikes so that we can all get to know you.  There is a wealth of information on the site, as well as with several of our members.  Some of us haven't tinkered with a Simplex since we were kids.....others have been playing with them for years.
thanks,
Mike Sal

[kjwiley]

  The cone and chamber have to be in the proper location. Come to think of it.. if I was going to go that far I might just retrofit a comet 125cc go-kart engine as a replacement for the stock engine.  I think I need another bike to build as a modified version? 

Ken