Topic: Swingarms: CB550F and CB750K1-K6 comparison.

[HondaMan]

Here's some pix for those of you who have asked me for them: the longer swingarm with the round tube frame is the CB550K and first year "F" arm. The other is a CB750K1-K6 style. (There were some differences on the CB750 K5-K6 arms in the pivot area, but the frame of the arm is the same.)

The arms will fit in each other's frames. The CB550F arm is about 1" longer than the 750 arm. It is also far less torsionally strong, compared with the 750 arm's welded box section, dual-channel construction.

If you want to shorten up a 550 wheelbase, here's one option! I'm not sure I can recommend the opposite approach, though: the stiffer arm is always the better choice for handling. 

[Beans]

I was wondering about making the swing arm stiffer so it wold handle better on my 550f.  I might have to try this in the future.

[Bankerdanny]

HM, what about the 750F arm. I know the F has a longer arm than the K, could you fit a 750F swing arm to the 550 frame and get a basically stock wheel base and gain the rear disk brake?

[sinister902]

HM, what about the 750F arm. I know the F has a longer arm than the K, could you fit a 750F swing arm to the 550 frame and get a basically stock wheel base and gain the rear disk brake?

thats precisely what I have done on my '75 cb550 using a cb750f1 rear swingarm/wheel/brake

[HondaMan]

HM, what about the 750F arm. I know the F has a longer arm than the K, could you fit a 750F swing arm to the 550 frame and get a basically stock wheel base and gain the rear disk brake?

Yes, it's possible, but REAL heavy! I think the 750F rear disk might be one of the heaviest rear discs in the vintage family. You will have to do some fab to mount up the rear master cylinder. You can also get tricky, like a Gold Wing, and make the rear master operate one of the duals up front, if you also add duals up there! Might want to bore the engine, though, to carry all that extra weight around?