Topic: Can a 500 performance cam, be used on a 550?

[L.A. Nomad........]

I picked up a 72 CB500k, with tons of aftermarket parts on it. Probably built in the early 70's, the original owner went to a lot of trouble seting up a dual disc brake. You'd think he would have used a later 550 right side fork, instead he made a special bracket or bought one! The bike has borrini alloy rims, S&W air shocks, rear sets, gas tank has gas gauge!, temp gauge, oil pressure gauge, Magura dog levers, fork brace and some other junk. The motor had a rusted out Kerker exhaust with a cone at the end, oil cooler, finned tapets, velocity stacks, some aftermarket ignition coil and finned covers everywhere.

Now I'm thinking, someone spent a lot of money on this Cb500, with lots of cool parts. So I'm thinking there might be a performance cam in this motor!

1-Can a performance cam from a CB500 work on a Cb550? (I just answered my own question, they're the same)
2-How can I tell the differance between stock and performance cam?
3-Can I just use a performace cam on a stock motor? (4-4 exhaust, stock ignition, etc)

Nomad...

[bryanj]

(1) Yes
(2) Measure the lobes
(3) not unless you want to ride a three legged multi-humped camel

[isred]

First off nice find.  in the Old Clymer manuals that have the hop up section they say you must put heavy  duty valve springs in or run the risk of valve float, which is not good. But if the 500 has a hot cam then it probable has springs also. For that matter look at the head and see if it been breathed on. anyways good luck, Brent

[L.A. Nomad........]

Lets say The Cb500 has a performance cam, then what should I do to my CB550 motor? Like I said it's all stock, with a 4-4 exhaust.

And yes I'm going to check the Cb500 head for porting and probably use the springs off the valves etc, if they are performance.

Nomad

[chung]

I would look into swapping the entire topend as a unit. Even the jugs and pistons. I don't do the 500/550 but I think they will be a simple bolt on swap.