Exhaust Mod

[mossy1200]

By my original idea , I take it you mean the suggestion from Mossy to build a collector box ?

If thats the way , does anyone know a collector box from another bike that can be modded ?
Something maybe like FJ1200 or the likes ?

Cheers

Most of the work is in welding the green sections off the diagram which is necessary with whatever you do unless you have gaps between each pipe(gaps will make it to wide for your underside).the wrap around is the easy bit once you have exit and entry prepaired.I have asumed you want cheep and to use stock headers as a starting point.
other option is a yoshi style 4into 1 (already complete) then weld a one into two outlet onto that then away.

Can you give us photo of your existing headers so I can see how the 4pipes meet on the genesis.Its been 15years since i owned 1000t model.

[Nemo]

This lil baby seems to solve my problems ( dependant on size) !

If its narrow enough to not stick out the sides of my bike I can have 4 inlets and 2 outlets as per 4-1-2

http://cgi.ebay.co.uk/FJ1100-FJ-1100-FJ ... 7C294%3A50

How do I upload pics by the way !!!!!

[yamaha_george]

Back to the main plot.............

Is this my only option ? Building a collector box to accept the 4 downpipes and then having twin exits from that ?

An old vf500 I owned had an aftermarket exhaust on it, that had a cylindrical collector on it with a side exit for the mid pipe and end can. A cylinder would be easier to make , any views on this one ???

Remember its a pre exup !!!

whether you go 4-1-2 depends on where that side exit is & how long that blanked off cylinder is if the memory of the theory is correct

[mossy1200]

It quite dear and could be to long.The system is just two two into ones with a large balance tube.This could be replicated with two y intersections and a hollow tube welded in between them.
You will need to reduce the mid pipes size smaller than the original single to keep the harmonics up or you will end up unable to tune the midrange.

[yamaha_george]

It quite dear and could be to long.The system is just two two into ones with a large balance tube.This could be replicated with two y intersections and a hollow tube welded in between them.
You will need to reduce the mid pipes size smaller than the original single to keep the harmonics up or you will end up unable to tune the midrange.

That sizing of the mid pipe is what worries me it is some weird equation to get it right.
The last time I did it as a mental thing was way back but i have no doubt the science has grown up and that calculators are far better than then. but I remember thinking that 66% OR 75% DIAM Would have been nice instead of some freaky number