Topic: Any better year of 550 than another?

[GroovieGhoulie]

I have read on the forum that the later 750s were more bloated and fat and due to federal emissions laws, got less powerful.

Did the 550 suffer a similar fate?  I prefer the 4-into-1 F models, but Ks are much more common and among the Ks I prefer the later straighter 77-78 exhausts.  However, if the later bikes were slower or fatter/heavier than the early 550s, I wouldn't want that.

Is there a particular year of 550 that is better than the others?

I'm on record as wanting a 75-76 400F, but they're rare as hell right now, so since I'm going to wind up with one each anyway, I may as well jump on a 550 if I find it.

[TwoTired]

I like the F models best.  77 would be most desireable, though there are minimal changes through the three years they made them; fork gaiters, mainly.
 The 77-78 K models had the lean burn carbs as they got closer to emission standards, and have more limited interchangeability with chassis parts from earlier models.
The exhaust system is where the weight differences occur.  4 into 4s are heavier than 4 into 1s.

Having said that, the condition of a 25-30 year old bike is gong to dominate any purchase decision.

I guess I really don't understand any ultimate performance comparrisons with these old bikes.  Any modern bike in the class will out accelerate and out maneuver the CB550 given equally experienced riders.  Does a few tenths in the quarter mile make that much difference?  Or, and extra 5 MPH top end?

The fun and charm of these bikes is the balance and behavior, not ultimate performance.
IMHO
Cheers,

[GroovieGhoulie]

The ONLY reason I prefer the F to the K is the swoopy, angled 4-into-1 exhaust.  I just like that header better than the 4-into-4 ones.  I like the 400's header better, with it's flat collector as opposed to the 550's box, which tends to group the pipes a bit too close for my tastes, but the 550F exhaust is nearly as good looking.

Performance is NOT an issue, but that artistic sculpture of an exhaust is.  I have NEVER seen a feature on a motorcycle that I found so drop-dead SEXY as that 400F/550F exhaust.

However, people seem to agree with me and 550Fs and 400Fs are hard to find, so I'm thinking of "settling" for a K, and then later "convert" it to F specs with NOS parts.

[grumburg]

Condition and price mean more than year. I lucked out finding a filthy, but solid 75 with near perfect exhaust and paint and rebuilt carbs for $200. Probably never happen again. You are better of spending the money for a decent bike rather thatn trying to bring back a pig. The parts  will easily exceed what the finished bike will be worth, or the price of a good one. They are not that hard to find.

[GeoffT]

The more I read on this site the more I appreciate getting my 550 F1 when I did. £350, plus about another £100 to get it on the road and through MOT looks more like a great bargain every day. After not owning a bike for 15 years (occasionally riding other peoples) it is a great bike for getting used to riding again. Now all I've got to do is persuade the mrs that I need another one to ride when I'm working on this one. 

[TwoTired]

However, people seem to agree with me and 550Fs and 400Fs are hard to find, so I'm thinking of "settling" for a K, and then later "convert" it to F specs with NOS parts.

I recommend you hold out for the F.  When I only owned a 74 Cb550K, I bought a 75 CB550F for spares.  Then proceeded to learn that very few assemblies are interchangeable.  They have different frames and many attach points and spacings for the bits that hang on the frame were different enough that they wouldn't swap.  Sidecover, tank, seat, even the rear wheel wouldn't swap as an assembly.
Further, the right footpeg and brake lever are different to accomodate the bulk of all the exhaust on that side.  It also possible that the exhaust hanger/rear footpeg may be in a slightly different location, as well.
The F carbs are jetted for the 4 into 1 and are different than those on the K, though the K's can be modified.

Another thing to consider is availability of the stock exhaust system.  I was told years ago by Honda that these were discontinued and no longer made.  Maybe David Silver Spares still have some left.  But, if you find a whole system, better glom on to it.

Cheers,