Topic: Replacement muffler for Kerker 4 into 1

[fatmatt650]

I know this is hardly a new topic but I can't seem to find what I'm looking for. I have a 77cb750f that I got from the original owner who worked at the dealership back in the day. The plan is to restore it keeping her original upgrades. The pipes are very sweet but the muffler is rotted almost completely through. Can anyone recommend a similar looking replacement while I continue to scour e-bay for an exact replacement?

I know it looks good in the photo but that shiny bit right at the bend is the only thing holding it together.

[Jerry Rxman Griffin aka MuthaF'er]

Mac USED to make a slip on which I bought for my stock header. No more however. Check with Buzz at Dynoman and see if he can get you a new Kerker muffler. I just bought a competition baffle from him for my Kerker.

[mick750F]

   FWIW...That isn't a stock muffler. Head pipes might not be original either, can't say fore sure.

Mike

Oooops...Just reread the post. Obviously you know what I stated above. I bought a NOS Kerker muffler on ebay a couple of years ago for around $40/50, so they can be had. You just have to keep looking and be lucky. You might find something that works for you here...
http://www.jcwhitney.com/jcwhitney/textsearch_result.jcw?sku=muffler&shopid=100003&_requestid=465149

[fatmatt650]

I'm about to order this - http://cgi.ebay.com/ebaymotors/Honda-CB750-F-Chrome-MAC-Megaphone-Muffler-1977-1978-_W0QQcmdZViewItemQQhashZitem27b69962e0QQitemZ170567230176QQptZMotorcyclesQ5fPartsQ5fAccessories

I assume it's the same as this - http://www.oldbikebarn.com/Chrome-Megaphone-Muffler-CB-750-F2?sc=2&category=37

It seems like it should bolt right up. Any have any experience w/ this set-up? I talked to Kerker and it's about $500 for a replcement, not really trying to spend that right now.

[RSchaefer]

I too am looking for a replacement muffler for my '75 F as my stocker has several rust holes, some significant.  I was trying to keep the stock look as much as possible and although the MAC looks OK and has a replacement baffle, its not nearly as look as the original and, to me, detracts somewhat from the "F" lines.  My original is 36" long!

I see where there are some Dunstall like options available (27") but they having smaller openings i.e. 1 5/8" or 1 3/4".  Are there adapters that would reduce the 2 1/2" 4-into-1 header pipe down to 1 3/4" and what effect on performance would this have, if any?

[Jerry Rxman Griffin aka MuthaF'er]

Looks like the Mac is once again available. Kinda pricey but cheaper than a new system. I liked the way it looked on my 75 F. Shorter and angles upward a little. It has good chrome and is heavy duty. The baffle is removeable. It is not a direct through baffle but rather 2 seperate pieces side by side that will restrict flow somewhat to achieve the baffling (no packing). I have thought about removing one half of the baffle. Not too loud but louder than stock. Bolts right up. I believe the 75/76 and 77/78 just have different mounting points. I never found anything else that was a simple bolt on and go.

[Skunk Stripe]

Another option might be a cyclexchange.net system. You can get their sidewinder pipe for a fair price. No idea how well they work though.

[fatmatt650]

The Mac was the wrong diameter for the Kerker. If anyone wants to buy it , let me know. I was thinking about trying this - http://inventorspot.com/articles/your_tailpipe_10416 - but I'm not sure how it would affect performance. Ultimately I did this -




I swapped the Kerker onto my 76f since it's more of a Cafe anyway and put it's stock headers onto the 77 in the photo at the top. They bolted up just fine despite having different part numbers for the 2 years. I did have to use a different bracket to bolt the muffler to the passenger peg. I just used a small length of that metal plumbing strap stuff and drilled the holes a bit larger.
The muffler solution on the Kerker was to simply tear off the rotten part at the muffler bend, hammer a disassembled bicycle hub into the end of the pipe, secure it w/ a screw, drill a bunch of holes and clean it up on the grinder. So far, so good.