Topic: CB550 clutch plate thickness mystery

[scottly]

Nobody can answer that question as we don't know the enginenumber of yours. In other words: is that the right part list for your specific model?

The first sentence of the first post reads:
"In question is a 1975 CB550K1 motor, engine# CB550E - 1034406"

[Deltarider]

so, is this right, or wrong. Supposedly a European export.

Nobody can answer that question as we don't know the enginenumber of yours. In other words: is that the right part list for your specific model?

[bryanj]

The picture of the clutch basket from the bike in question DOES NOT have the wider slots at the outer end, this is suposedly the original.
The CMSNL parts fiche for the CB 550 K0 shows plates with the outer one having wider tangs, therefore if the bike has not been touched the parts list is wrong.

Now as the first UK 550 was the F1 followed by F2 and K3 so i have not PERSONALLY stripped an early 550 clutch so i will bow to Marks knowledge who HAS worked on these and specifically states that he knows Honda dealers regularly got it wrong and if dealers got it wrong the aftermarket people are bound to follow suit.
As to the 500 transmission i have yet to find one with 4 selectors but i have several parts books that say so

[jonda500]

   Maybe the old clutch friction discs encountered some friction modified oil at some point? When I used a friction modified oil (castrol GTX) in my 400-4 in the eighties, the clutch started to slip. No amount of changing the oil and thoroughly cleaning/sanding the original discs could fix them! I had to replace them.
   I have the same parts list as jlh3rd for my '75 550F. Like in the parts list, my 550F has no dual steel "slipper?" plate in the middle, just 6 steel plates all the same, 6 friction discs all the same and 1 outer friction disc with wider fingers. The friction discs all have straight cuts, none are slanted.
   My CB500 K, K1, K2 parts list has 3 different part numbers for the 7 friction discs, and the picture shows straight cut discs? (My 500 has slant cut!)
John

[HondaMan]

   Maybe the old clutch friction discs encountered some friction modified oil at some point? When I used a friction modified oil (castrol GTX) in my 400-4 in the eighties, the clutch started to slip. No amount of changing the oil and thoroughly cleaning/sanding the original discs could fix them! I had to replace them.
   I have the same parts list as jlh3rd for my '75 550F. Like in the parts list, my 550F has no dual steel "slipper?" plate in the middle, just 6 steel plates all the same, 6 friction discs all the same and 1 outer friction disc with wider fingers. The friction discs all have straight cuts, none are slanted.
   My CB500 K, K1, K2 parts list has 3 different part numbers for the 7 friction discs, and the picture shows straight cut discs? (My 500 has slant cut!)
John

I encountered a 550 that had the same problem following the use of the GTX oil (it's for car engines), but the guy was about flat broke. So, in a last-ditch attempt to 'save' the plates I soaked them in gasoline for 2 days, shaking up the pan a couple of times per day. Afterward I washed them off (soap and water) and then dipped them in Castrol XLR (boy, I miss that oil!) and changed the bike's oil to that type, too. After about 100 miles the plates gripped much better, and I don't think he ever changed them again after that? I'm supposing they worked fine, it was his daily rider to work, and although I saw him riding from time to time I never talked with him again.

That was a LONG time ago, in the other century.

[bryanj]

John, if you look at the pic showing the OP clutch basket(NOT the first pic) it does not have the wider slots at end.
The "slipper" steel plate or twin steel plate was only in the later models and is a GL 1000 part

[Deltarider]

[...]
The "slipper" steel plate or twin steel plate was only in the later models [...]

Correct, that steel plate is first mentioned in p.17 of the CB550F2 parts list. https://www.honda4fun.com/dwnload/Part-List/CB550/CB550-F2-Parts-List.pdf That plate was fit from engine serial number 1139189 on.
Good someone took the effort of scanning and then uploading his paper CB550F2 Parts List, so all the world can consult it... and find out how important it is to have the appropiate parts list.