Raising the stock mufflers?

I recently posted about swapping out the stock mufflers on my '82 KZ750H3 for something similar but smaller, and was told that the stock 'megaphone' type mufflers were the best for the bike (that with others the engine might not run as well).

Okay, that makes sense. Here's the problem; I recently lowered the rear end 3" with struts and installed a springed solo seat (I'm slowly bobbing this thing). It actually rides nicely and not too harshly, but the stock mufflers are scraping the ground on tighter turns, hence my reason for wanting smaller ones. The exhaust system is all welded, no clamps. Is there a way I can bend them up a bit without damaging the header pipes where they connect? Perhaps cut them off and clamp in a short, slightly curved piece of tubing?

Pics of where you need them bent. Im thinking a muffler shop could do on a madrel bender.

polkat wrote:

I recently posted about swapping out the stock mufflers on my '82 KZ750H3 for something similar but smaller, and was told that the stock 'megaphone' type mufflers were the best for the bike (that with others the engine might not run as well).

You should have no problems running a different exhaust system. Just make sure you rejet your carburetors and you'll be fine.

Later, Doug

I'll try to get a pic, but I need to bend them up a bit where the front of the muffler connects to the header pipe, so that the back end of the mufflers comes up about 3".

StreetfighterKz, I'd like to run some slip-ons if I can find them, but my knowledge of motorcycle fuel systems is not yet up enough to match jets with specific mufflers. If I could find something with roughly the same back pressure, I'd be better off.

If you are still running the stock air box you should be able to get away with not rejetting with an exhaust change provided you don't run an unbaffled pipe. If you do have to rejet it would likely just need an increase of one size on the main jets, but I'd be surprised if it ran poorly without rejetting. I ran a mac 4-1 on my first kz650 and didn't have to change jetting until I switched to pod filters instead of the airbox.

polkat wrote:

I'll try to get a pic, but I need to bend them up a bit where the front of the muffler connects to the header pipe, so that the back end of the mufflers comes up about 3".

I might think the solution would be to cut the pipe about 1" ahead of the muffler and weld in some kind of a flanging connector to put in the bend you need. You might also do a "angle cut" on the pipe piece on the muffler side to angle it up and then just weld the original pipes back together and grind the welds flush.

polkat wrote:

I'd like to run some slip-ons if I can find them, but my knowledge of motorcycle fuel systems is not yet up enough to match jets with specific mufflers. If I could find something with roughly the same back pressure, I'd be better off.

Earlier you said that you had a 1-piece exhaust system. If that's the case you'll only find aftermarket full systems for your bike.

Also if you have the capability to clean a set of carbs you can rejet. I'm sure others on here have rejetted their bikes and can offer jetting suggestions.

Later, Doug