MAC 2:1 exhaust for 1980+ GS450 - will it fit 77-79 GS400/425's?

[Chuck78]

Any idea if the 1980+ GS450 exhaust made by MAC is at all adaptable to fit the first gen GS400/425 engines? I see no aftermarket exhausts listed anywhere for the first gens. They are a totally different bore and stroke, so I assume there is a slight difference in engine height, but not sure how much different and if it has much affect on the cornering clearance or oil pan/frame clearance.

Contemplating my next build with these and many thoughts on mods.

[vitaliy.grzh]

12 years later, but yeah they should fit, id buy a Japanese 2 into 1 or maybe a European Marving style 2 into 1, removable baffle and all

[Chuck78]

12 years later, but yeah they should fit, id buy a Japanese 2 into 1 or maybe a European Marving style 2 into 1, removable baffle and all

Yeah I actually picked up one of those used as well as another junkyard exhaust of unknown manufacturer that was on I believe a GS 250 twin, which also works. It had some generic universal muffler welded to it that I'd cut off to graft a kirker mid-pipe and muffler can onto


I've been eyeing up all of those cool Japanese exhausts on Japan.WeBike.net for ages, I wish I had bought one when I first started looking at them because the exchange rates were considerably in our favor back then, and now the exchange rates and tariffs are considerably against USA buyers...

I wasn't aware of Marving making one, but I always really loved their flat collector 4 into one pipes. If they were stainless or titanium, I would have been jumping through hoops to get one of those for my GS750 big bore, but I've been really happy with Delkevic offerings, being all stainless and good quality. The flat collector 4:1 Marving design is definitely my favorite on the market.
A few of those Japanese GS400 pipes are similar although you don't have to worry about double stacked header tubes on a twin cylinder bike so they're nearly all like the Marving in that regard...