Topic: Exhaust flange/clamp -- how to clean 'em up? Paint? Treat?

[Oddjob]

How odd, that's the colour of my crankcases. The colour you want if you want the chrome look is called CermaKrome

https://techlinecoatings.com/cermakrome/

[MauiK3]

Sounds simple, worth a test try

[jonda500]

I checked the part numbers:
500&550F both have 18231-323-000
550K has 18231-333-010 (edited- corrected from 323 to 333)
400 has 18231-333-010
One of the second hand pairs I purchased from ebay were from a 400 four, they were the shorter fin type - I still have no idea which type came earlier?
John
btw Fantastic detailing work Oddjob, I know what a long time that would have taken! Thanks for sharing that.

[Oddjob]

The 550f, has a 333 middle part number, or has in the UK. Which means you were correct as that’s a 400-4 part. The CMS pic shows the narrow rear wall.

[newday777]

The 550f, has a 333 middle part number, or has in the UK. Which means you were correct as that’s a 400-4 part. The CMS pic shows the narrow rear wall.

The 333 was the 350four

[newday777]

The 550f, has a 333 middle part number, or has in the UK. Which means you were correct as that’s a 400-4 part. The CMS pic shows the narrow rear wall.

550F Supersport is 390

[Oddjob]

Oh yeah, 377 was 400-4. We didn't get the 350-4 in the UK, there are some about but they were never imported by Honda UK to my knowledge. I just equate the 350 and the 400 as essentially the same bike, they share so many parts.

550F2 has an awful lot of 404 parts fitted as well, shares a lot with the 550K3.

My post was to inform Jonda500 that he must have misread the 323 middle number for the 550F, easy to do, they look the same at first glance especially if you're expecting to see 323.

[jonda500]

Actually I mistyped in my previous post (mixed up the K and F numbers) - to be clear I will copy from Honda parts lists the finned JOINT part number and the COLLAR part number:

CB500  18231-323-000  JOINT 
             18233-107-000  COLLAR

CB550F 18231-323-000  JOINT
              18233-107-000  COLLAR

CB550K 18231-333-010  JOINT
&500K3 18233-107-000  COLLAR

CB400    18231-333-010  JOINT
               18233-303-010  COLLAR

well that is still pretty unclear, but I am going to go out on a limb and say that they are ALL interchangeable on all of the smaller SOHC/4 Hondas, John
p.s. I checked with my strong glasses on - the 500K3/550K definitely has 333 model code number???

[Oddjob]

Actually we are both right and both wrong. I have this annoying habit of always selecting the CB550F2 whenever I go to look up parts for the 550f, mainly because that’s the one I owned, however after your post I thought, did I misread the parts book? But no I didn’t and neither did you. The 550f and 550f1 did indeed carry on using the old 500 exhaust clamp, the 323 middle number, however that changed for the 550f2, not only did they change to the 350f part, 333 middle part number but they ditched the spring washer and went to a flanged 6mm nut.

No idea why Honda suddenly changed the clamp, maybe they ran out of the 500 clamps and were scratching around looking for an alternative. Or maybe it’s 2 grams lighter and as they say “ every little helps”

[Ozzybud]

Likely the 333 collars that were designed for the 350F and also used on the 400F's which never used spring washers were a little thinner and gave the flex/tension required to eliminate the Washers.  Honda Engineering was on point!

[Oddjob]

That’s entirely possible. Plus Honda really did like to save money whenever possible 😁😁😁

[HondaMan]

Or maybe it’s 2 grams lighter and as they say “ every little helps”

...was that maybe where the performance increase of the later model came from?