pipes

[guzzi john]

 Anyone tried using exhaust bits from twins,triples, or fours? With the huge variety of bikes built over the last 30-40 years one would think such an adaption is possible. Half a 4 cylinder's 4 into 2 perhaps. A two pipe setup like the Moto 3 bikes have is interesting. The Thumper pipe is nice but a $200+ pipe on a $500 bike is a bit much for me. GJ

[scottly]

Now that you mention it, I've been busy lately fabricating a system from pipes cut from an aftermarket (?) header from a Kawasaki 550. (I have more time and bits laying around than money. )

[J6G1Z]

How much is your time worth? The Thumperstuff header is a very nice pipe & bolts right up! You will also need a new muffling section to go with the Thumperstuff pipe. Rumor has it that there are only 4 of the Thumperstuff headers left in stock. Once those last pipes are sold, I'd be surprised if there is another run.

J.

[J6G1Z]

I have heard of attempts to use an XR or XL pipe from the same era.

J.

[guzzi john]

Thanks Scotty,that's what I figured someone had done. Some years ago I built a system for an XV920R that consisted of proper skinny equal length pipes going to a small collector ending with a pair of Supertrapps. Fabbing from scratch is pricey so junk pile sourcing is where I'm looking(of course I scrapped a couple of Kawi 750 headers last year ). Thought about XL/XR but they run where stuff exists on the FT right? GJ

[scottly]

The XL/XR pipes have a smaller OD where they meet the head than the FT, with 32mm copper gaskets vs 37mm. On the '82 XR, the pipe tucks inside the frame where the FT battery is located. I don't know about the XL, or the earlier twin-shock XR.

[J6G1Z]

I'm not sure how the various years XR/XL pipes run. Some are mid pipes.


Scottly, that exhaust looks like it will flow well. How does it run so far?

[scottly]

So far, it seems to run OK, but I was only able to ride a short distance yesterday before a fierce thunderstorm blew in. The collector isn't welded in, and leaks badly, so when I get it on the dyno I probably won't get reliable sniffer results. Since I have two head-pipes left over, I may build another setup with the short pipes merging together in front of the frame like the HRC pipe. Also, the ID of the Kawi pipes are a little larger than the Thumperstuff at 1.270", which may not be a good thing?

[scottly]

Here are some pics of what lurks inside the stock exhaust system.