Topic: 1975 CB550K questions

[cbnewb]

Greetings,

I've been fortunate to stumble upon a low-mileage barn-find 1975 CB550K recently.  To my knowledge, this bike was only offered with a 4-into-4 exhaust from the factory.  This bike, however, is running a 4-into-2.  Normally I would just assume this was a typical after-market modification made at some point in its past, but it certainly has a factory look to it.

My questions:  The 550s were only offered with 2 exhausts - 4-into-4 for the K model, and 4-into-1 for the F model, correct?  Also, other purchasing a 4-into-4 on Ebay which has been scavenged off another bike, and may be of questionable quality, has anyone found a decent source of 550K 4-into-4 replicas, or any luck with NOS parts?

Currently the exhaust from cylinder #4 isn't getting warm, I've have had to maneuver my way past the seat lock and will be removing the tank this weekend.  Cables are the most obvious source of problems, but I'll be rebuilding the carbs after removing them.  Any recommendations from the group regarding good quality kits?  (The plugs have all been replaced, points have been adjusted, and it has been timed)  It's very possible #4 simply isn't getting any fuel at this point.

It's surprisingly clean, though has obviously suffered its share of weathering.  I can't see modifying it in any way as I have other bikes to play with for that - would like to get it back to "better than factory" condition with everything similar to how it was back in 1975.

Thanks for your time and suggestions,

CBN

[cbnewb]

I'll attach a picture.  I believe I had a typo above.  I meant "wiring" rather than "cables". 

[Gordon]

Nice find!  You're correct in that the only stock exhaust for the 550K is a 4-4.  The 4-2 that's on your bike is an after market item.  If you want the stock exhaust and don't want to get a used set Honda still has them.  Check with your dealer or you can order them from David Silver Spares.  I installed a brand new set for a friend last year that she purchased from DSS and they look great. 

[bryanj]

The difficult bit is thebrackets that are seperate from the exhausts. Dave Silver has had these re-manufactured and you can get everything including connecter rubbers with clamps and stand rubber from him in one hit

[bender01]

You can still buy 550k pipes from honda. I did last fall. It will be somwhere @ $850 with the bits that go with them. If you click the signature to my bikes you can see the old pipes i replaced. Functional and patched undersides. They are boxed and ready to sell if your interested. I have many pictures if youd like. Thats a great bike. It took me three times to get my carbs clean so go easy. Be careful and you can reuse the floatbowll gaskets and avoid buying rebuid kits. Use Simple green if you can and it wont eat the rubber off the jets. Search carb cleaning and simple green. Yull find alot of info.

[TwoTired]

It's pretty hard to imagine that original orings from 1975, hardened with age, will reseal after being disturbed.  Honda still sells a kit with all the rubber bits for replacement.  I suppose you could give old ones a try, though if you don't mind going through the rebuild process more than once.

All the K models were 4 into 4 from factory, according to the Honda motorcycle identification guide, published by Honda.