Hello wise group. I have been popping in and out of this informative group over the past year and I thought I'd finally ask for some sound advice. I just purchased a Kerker 4-1 exhaust for my '78 550k. One it warms up here in Minnesota (if it ever does) I'll want to switch the stock exhaust with the replacement system. I've switched pipes out of my 350 twins before but not on a sohc4.

What suggestions do you have for the proper steps in regards to install and tuning after they are installed? Should I have any concerns going from a 4 into 4 system to the 4 into 1?

Thanks in advance for your response.

- Mike

-- Mike Hoyt (hapa9@bitstream.net), February 28, 2002

Answers

Its one of the easier tasks you can do. The Kerkers were well designed and meant to be easy to install. However, don't forget to replace the exhaust gaskets. You can get Honda replacements, or Vesrah makes these gaskets. The Vesrah's cost about the same, but I have a feeling that they are of better quality. You'll definitely need to rejet, especially if the jetting is stock. I've gone from 95s to 107.5 on my bike with the stock pipes, so you can probably expect to use about 110-115 main jets. Thats just a starting point, you may need to more or less, depending on your bike. Also, if you're replacing the exhaust for performance more than styling points, you'll want to think about removing the airbox, and replacing it with (most likely) individual filters K&N, uni, etc. Doing all this will be the only way you'll really see the gains from this exhaust system. BTW, where did you come across a Kerker, is it a swap meet part or (please,please, please) is there some company that has a few to sell. I would like to replace the stock pipes, but can't find anything on the aftermarket except MAC pipes. I made a mistake with MAC once and am not willing to waste the time or the money on them again. Best luck

Jeremy

P.S. If you decide to stick with the stockers I'd be more than willing to take the Kerker off you hands, I'll match whatever you paid for it, plus pay shipping. Think about it

-- Jeremy Farlow (jermosirus@hotmail.com), March 03, 2002.

Hey Jeremy, Thanks for the response and advice. I emailed a response re:pipes. Thanks -Mike

-- Mike (hapa9@bitstream.net), March 06, 2002.

Mike,

Hey, I'm up here in Minne"snow"ta, too, with a '78 550k. I'm waiting for the warm-up too, but this is the first "winter" in recent memory that I've gotten in at least one good ride each month. Very strange winter...

I installed a 4-into-1 a few years ago, and it was very easy. While I agree with Jeremy that you probably should pick up a set of the copper exhaust gaskets, (I went with Vesrah's)I don't think you need to rejet. I sure didn't feel like I needed to.

You'll probably need to rebalance your carbs, though, now that your back pressure will be all nice and even.

I just picked up a set of mercury-sticks to rebalance mine. Are you in the Mpls area? I'd be happy to help you get 'em balanced once it warms up.

Matt

-- matt reinert (mjreinert@prodigy.net), March 07, 2002.

Thanks Matt, I emailed you a response. -Mike

-- -Mike (hapa9@bitstream.net), March 12, 2002.

Matt, I forgot to ask you one thing. Did you buy your gaskets locally or online? If you know of a good cheap place to get parts let me know. I generally go to Honda Town (Super pricey) or Midwest Cycle Supply (can be ok). Anyhow, Thanks! -Mike

-- - Mike (hapa9@bitstream.net), March 12, 2002.

I have just picked up a super clean 75 550K and would also like to put on an aftermarket 4 into 1 exhaust. Since I'll probably try to get these used, does anyone know what other bikes these could have come off, i.e. 350 / 650 / 750.

P.S. I'm reliving my childhood as my 1st street bike ever was a 77 550K (it was only 3 years old then).

Thanks

-- Kevin Shanks (kevin.s.shanks@marsh.com), May 14, 2002.