Topic: Will a cb550f header / exhaust work on a cb550?

[bubruins]

This may be a stupid question, but I have found no evidence that it will work or that it will not work. I'm looking for a cheap 4-1 that I can refinish and a well worn cb550f header looks like it just may be the ticket for my cb550 build. If it matters, my bike is a 1975. I figure that I will just buy the header for now and fit an appropriate muffler and pipe to it later in the build so any mounts past the exhaust flange do not matter at this time.

Thanks

[TwoTired]

The F bikes have a brake pedal, kick starter, and foot peg offset (as well as frame mods) to accommodate the extra bulk of four pipes.  The K models do not.

If you do enough work/mods, I suppose you can make it work.  But, it is not going to be a bolt on affair without some change to the collector/position.

There have been posts made about this earlier, btw.

[bubruins]

Thanks for the input. I was planning on rear sets so I'll see what the clearance looks like with those and modify the pipe as needed.

Also, I searched this site for "cb550f exhaust cb550" and a couple similar search terms with no relevant results. I guess I just need to get better with key terms on this website.

When I get the exhaust in I'll post some pics and dimensions.

[NickC]

I did it with some heating/bending. If you can find the splined brake pivot off the F bike, it would make the clearance a little easier, I'm pretty sure it is longer than the K and will bolt up

[TwoTired]

If you already decided to use it, one has to wonder why you posted the question at all?

[bubruins]

I had not purchased it yet. Someone offered it to me and upon the news of hearing that the pipes at the head would fit I decided to go for it. It'll be in the mail Monday and I thought that it might be helpful to some others if I posted some pictures of the fitment and what I think will be the best way to modify it. For poor people like me it may be a good way to pick up a $60 4-1 header (I know it'll be closer to $100 by the time I'm done with it) and make it work instead of dropping $249 for a new Mac pipe. Also, I have a friend with a CBR 929 oem muffler that he needs to get rid of so I'll see what the dimensions are off of it; ideally I could use it.

[NickC]

this is after bending. Before bending you won't be able to bolt it on. I adjusted my rear brake also. At this position I can stand on the brake pedal and it just touches the pipes. The little crappy muffler on there was dragging in right turns, but I have since added an up swept pipe and kerker muffler and now have plenty of clearance.

[TwoTired]

With the stock pipes you can lean over and scrape the foot pegs without hitting any pipe bits.

[fastbroshi]

   From all indications, my bike started as a K and the F exhaust bits and whatnot were added to make it work.  From pics I've seen, the telltale sign, other than the passenger peg supports being of the stamped steel variety and not the tubular ones, is the metal tube that the splines brake shaft doesn't come close to enclosing the shaft.  There's also no provision on this tube for a return spring, so you'll have to go to Home Depot or whatever to figure it out.

http://forums.sohc4.net/index.php?topic=5404.0

[NickC]

With the stock pipes you can lean over and scrape the foot pegs without hitting any pipe bits.

Thats good to know, because the bike with the F pipes yields the same results....

[TwoTired]

With the stock pipes you can lean over and scrape the foot pegs without hitting any pipe bits.

Thats good to know, because the bike with the F pipes yields the same results....

Must have ended up different than what was pictured, then.  Because that thing is gonna drag on the street, particularly with the rear springs compressed from g loads.

[fastbroshi]

Too bad you bent that header Nick, if you'd gotten the brake shaft and pedal for the F I think you woulda been alright.

[NickC]

Too bad you bent that header Nick, if you'd gotten the brake shaft and pedal for the F I think you woulda been alright.

Eh, it can always be bent back, doesn't take too much effort.


And TT, I guess you missed this......

The little crappy muffler on there was dragging in right turns, but I have since added an up swept pipe and kerker muffler and now have plenty of clearance.

[TwoTired]

And TT, I guess you missed this......

The little crappy muffler on there was dragging in right turns, but I have since added an up swept pipe and kerker muffler and now have plenty of clearance.[/quote

I didn't miss it.  I'm just skeptical.
The F model offsets the brake arm to move past the 4 pipe collection on the outside.  This is both a brake arm difference AND a frame difference to create this offset.  If you moved all four pipes to be lower, so that the brake arm travel is not limited by the pipe collection, then I don't see how it could not scrape before the foot peg during extreme lean over.  From the posted pic, even with the muffler completely gone, it sure looks like the header collection is going to scrape before foot peg, even without rear spring compression moving the tire up toward the fender.

Perhaps it is a photography angle illusion.  But, I just can't see the clearance in the plane from tire tread to end of foot peg.

[NickC]

That picture does seem to be misleading. I do believe I bent the pipes closer to the centerline after that pic was taken to help alleviate the problem.
I had some scrap plate steel lying around, so I made 2 pieces to represent the length of a fully compressed suspension. The footpeg will definitely hit before anything else does......

[jonathantaylor86]

Will a 75' CB550 SS header and pipes fit on a 72' CB500?

[TwoTired]

It will fit the engine ports.
You'll have to do some mods to the brake arm, the kick start lever, and maybe the foot peg, as those are all different on the F model bikes.