compatible exhaust system

hi, im looking for some advice about which exhaust systems will fit my 1982 xj 750 maxim,
will an xj 550 collector box fit the 75o as mine is now rotten ( just what i need before summer)
I have seen a few systems online (preferably 4 into 2) for the 650 so looking to be pointed in the right direction.

I am in UK and finding it a bit difficult to source a system here,

Thanks, Kenny

 

if you post some measurements I can compare them to an exhaust I have sitting on my bench
pipe input muffler pipe size at out put spacing of inputs

 

The 550 collector will not fit a 750. A 650 Seca collector will, as will one from a 750.

 

The only collector box that will fit properly with the stock header pipes and the stock mufflers is the one from a 1982-83 XJ750 Maxim. The collector boxes differ in their input receiver angles AND. especially, in their output joint pipe angles (up/down and "splay" angles), and without the proper collector, you'll have a very difficult (or impossible) time getting the rest of the exhaust system to "fit" and line up properly.

For example, XJ750 Maxim mufflers are "straight" from their connecting point to the very end, whereas XJ750 Seca mufflers have a pronounced "bend" in the pipe (about 30* or so) a foot or so after it leaves the collector. These differing angles change:

a) the point where the muffler can hangers attach to the muffler mount points on the footpeg brackets, and....
b) change the "cut" of the very rear of the muffler can.

The "bend" in the muffler corresponds to the output angle of the collector outlets, and also somewhat to the input angles of the collector at the front (headpipe) end.

So if you tried to use the "straight" XJ750 Maxim mufflers with a "bent" XJ750 Seca collector, the greater upswept angle of the 750 Seca collector outputs would result in the mufflers pointing skyward to a significant degree, they would rise up at the back end almost to the bottom of the seat, and of course the muffler hanger brackets would be far above their mounting points on the footpeg brackets...........


This is why it's a challenge to swap collectors between different models. Also, be aware that some models used different sized header pipes, the bigger engines tend to get larger diameter pipes (except for the 650 Turbo models, they kept the pipe diameters smaller to speed up the gas flow and keep the turbine spinning even at low engine rpms), and the larger diameter pipes of course won't fit very well in collectors designed to accept smaller OD pipes!

Finally, the above observations are generally also true within any model(s) that had a Maxim vs. Seca model ("bent" muffler cans vs. straight muffler cans). Of course, the XJ650 Maxim system is in a world of it's own, because like the XJ1100 models, it's doesn't use a real "collector"; instead a quasi-collector is built into the front of the (amazingly long) muffler cans and there is a cross-over pipe involved, too. And the XJ650 Turbo models, while still using (a robust and quite beautiful) cast-iron collector, has a single, centrally-located output (rather than dual side outputs like all of the other traditional collector boxes do)..............

 

hi thanks for that, do you know if the 650 exhaust pipes will also fit the 750

thanks kenny

 

See Chacal's post above.

 

I did an exhaust comparo and write-up awhile ago--- I can't find it anymore, but if you search, you might find it. If you do, let me know the link to it..... I just don't know what I called it--- lol

 

Thanks, I will have a good look

Kenny

 

Hello chacal will XJ550 uk model silencers fit onto an XJ650 collector box and footrest mounts , they look quite similar

Thanks

Steve(chips)

 

Hi all,

Anyone know if a XJ 750 Seca (11M) exhaust fit a 41Y XJ 750? I'm having trouble finding an exhaust for my 41Y...

Thanks,
PJ