Topic: 550K/550F Differences

[TheHulk]

Hey all. I built up a '77 CB550F a few years ago. The VIN Badge on the frame indicated that is is indeed an "F".

I just ordered a set of pipes from a relatively well known vendor, and they don't come close to fitting. Not only were the distances between exhaust ports too large, but the OD of the headers were too large to slip past the engine casting that holds the header studs.

For example, my old OEM pipes have an OD of approx 37.4mm, while the pipes I ordered have an OD of about 41.7mm.

Upon looking at Delkevic's site, the list two different 4 into 1 models. One for CB550k, and one for CB550F.

Are there any differences between the F and K frames or engines? I was under the impression there weren't.

The stamp on my engine is CB550E-1147556

Thanks!

[bryanj]

All heads, including 500 are the same, the difference in model is where the rear footrests are so different silencer mounting points, i suspect the system you have is for a different model, maybe later twin cam

[TheHulk]

Got it! Thanks.

[kerryb]

To assist your research, these are diameters of the headpipes on a hm 390 pipes for a cb550f  they are:  37.54, 37.62, 37.73, 37.71.  The measurements on an aftermaket 4:1 that came off a 77cb550f were all under 36mm.

[TheHulk]

To assist your research, these are diameters of the headpipes on a hm 390 pipes for a cb550f  they are:  37.54, 37.62, 37.73, 37.71.  The measurements on an aftermaket 4:1 that came off a 77cb550f were all under 36mm.

Awesome! That is incredibly helpful.

[Tracksnblades1]

Was you able to figure out what pipe was actually sent to you..?.

[TheHulk]

Was you able to figure out what pipe was actually sent to you..?.

I ordered the 4 into 1 "Yoshi Style" CB550 pipes from Carpy's. That appears to be what I received, but... they don't fit.

[kerryb]

Do you have any pics of what you received from Carpy’s?

[Stev-o]

Was you able to figure out what pipe was actually sent to you..?.

I ordered the 4 into 1 "Yoshi Style" CB550 pipes from Carpy's. That appears to be what I received, but... they don't fit.

This?
https://carpyscaferacers.com/shop/shop-our-store/motorcycle-parts-accessories/honda-cb500-cb550-cb750-parts-upgrades/stainless-steel-4-into-1-exhausts-for-cb500-cb550/

[TheHulk]

This?
https://carpyscaferacers.com/shop/shop-our-store/motorcycle-parts-accessories/honda-cb500-cb550-cb750-parts-upgrades/stainless-steel-4-into-1-exhausts-for-cb500-cb550/

Yup that's the one