Author Topic: Clutch plates  (Read 3908 times)

Offline Trigger

  • Grogu
  • *
  • Posts: 8436
  • Engines built on reputation, not advertising.
    • View Profile
Re: Clutch plates
« Reply #15 on: June 29, 2023, 07:51:26 PM »
So you have a K2 clutch that was fitted to the UK K2 from 1972 to 1974 .

Your bike must have been registered in 1975 but, was it manufactured in late 1974 ? If so the clutch components you have in the picture are correct. 

Offline Trigger

  • Grogu
  • *
  • Posts: 8436
  • Engines built on reputation, not advertising.
    • View Profile
Re: Clutch plates
« Reply #16 on: June 29, 2023, 07:59:19 PM »
Now we are getting somewhere. Your springs should be 35.50 mm to 36.00 mm in length and those steel plates need a good clean, if you haven't already done so.  ;) 

Offline Pauarc

  • SOHC Member
  • Posts: 209
    • View Profile
Re: Clutch plates
« Reply #17 on: June 29, 2023, 08:12:43 PM »
Before I fitted new plates I put the steel plates in a ultrasonic cleaner springs are new
Honda 90ss, Cb250k1 supper sport,
Cb400 four, CB750k7, Cb550, Cb750f2n,
Cb750k2

Offline Trigger

  • Grogu
  • *
  • Posts: 8436
  • Engines built on reputation, not advertising.
    • View Profile
Re: Clutch plates
« Reply #18 on: June 29, 2023, 08:41:48 PM »
The steel plates have a covering of dimples, these dimples trap oil and need to be very clean.
Did you put all the steel plates in with the flat side to the engine and the beveled edge facing out ?
Just because the springs fitted are new, there are two types so, you need the correct length ones as mentioned before  ;)

 

Offline Pauarc

  • SOHC Member
  • Posts: 209
    • View Profile
Re: Clutch plates
« Reply #19 on: June 29, 2023, 09:01:02 PM »
I just checked the old ones they are 31.5 mm the new ones are 31.9mm I made a note and yes flat side in and bevelled side out.
this is the length off springs in the manual I have
Honda 90ss, Cb250k1 supper sport,
Cb400 four, CB750k7, Cb550, Cb750f2n,
Cb750k2

Offline Trigger

  • Grogu
  • *
  • Posts: 8436
  • Engines built on reputation, not advertising.
    • View Profile
Re: Clutch plates
« Reply #20 on: June 29, 2023, 11:14:13 PM »
The shorter spring was used in the 750K0, K1, and some early K2's. Then it was superseded to the longer spring with a smaller diameter coil. Early spring at the top later at the bottom in the picture. The longer one just means a smoother clutch. [ Guests cannot view attachments ]

Offline Trigger

  • Grogu
  • *
  • Posts: 8436
  • Engines built on reputation, not advertising.
    • View Profile
Re: Clutch plates
« Reply #21 on: June 29, 2023, 11:22:05 PM »
spend a bit of time putting together a K2 clutch so you can see the stack measurements. Much easier to build the clutch up on the bench and then put it in the engine. You should end up with a stack at 37mm
You can pull the clutch together using washers on the springs and then you can see what is going on.




[ Guests cannot view attachments ]


Offline Trigger

  • Grogu
  • *
  • Posts: 8436
  • Engines built on reputation, not advertising.
    • View Profile
Re: Clutch plates
« Reply #22 on: June 29, 2023, 11:23:50 PM »
[ Guests cannot view attachments ]




[ Guests cannot view attachments ]

Offline Trigger

  • Grogu
  • *
  • Posts: 8436
  • Engines built on reputation, not advertising.
    • View Profile
Re: Clutch plates
« Reply #23 on: June 29, 2023, 11:26:33 PM »
One thing i forgot to ask, what was wrong with your clutch in the first place ?

Do you have a thin washer behind the basket ? and the thick keyed washer in front of the basket ?

Offline Pauarc

  • SOHC Member
  • Posts: 209
    • View Profile
Re: Clutch plates
« Reply #24 on: June 30, 2023, 07:56:11 AM »
The clutch drag a bit before and gear change was clunky old plates were hard not any better with new plates no thin washer that I can remember but there was a thick washer
Honda 90ss, Cb250k1 supper sport,
Cb400 four, CB750k7, Cb550, Cb750f2n,
Cb750k2

Offline Pauarc

  • SOHC Member
  • Posts: 209
    • View Profile
Re: Clutch plates
« Reply #25 on: June 30, 2023, 09:58:58 AM »
I have just set central nut as you suggested have not tried yet as out today
Honda 90ss, Cb250k1 supper sport,
Cb400 four, CB750k7, Cb550, Cb750f2n,
Cb750k2

Online K2-K6

  • Grogu
  • *
  • Posts: 5287
    • View Profile
Re: Clutch plates
« Reply #26 on: June 30, 2023, 11:52:01 AM »
Some good details and specifications there from Graham.

Adjustment looks reasonable from arm position, it's just trying to bring maximum lift that can be attained with the lever/cable etc by adjustment to very small gaps in each stage.

Lever end free movement is in the manual at 10~25 mm, with that set to minimum @ 10mm it should reach the largest lift space possible on the plates/clutch pack and give the least drag in operation.

Offline Trigger

  • Grogu
  • *
  • Posts: 8436
  • Engines built on reputation, not advertising.
    • View Profile
Re: Clutch plates
« Reply #27 on: June 30, 2023, 02:22:36 PM »
Some good details and specifications there from Graham.

Adjustment looks reasonable from arm position, it's just trying to bring maximum lift that can be attained with the lever/cable etc by adjustment to very small gaps in each stage.

Lever end free movement is in the manual at 10~25 mm, with that set to minimum @ 10mm it should reach the largest lift space possible on the plates/clutch pack and give the least drag in operation.


There is something strange going on. I have built a shed full of K2 clutches over the 32 years in the engine  business and it is one of the easiest ones out of the 750 range.  ;)

Offline Pauarc

  • SOHC Member
  • Posts: 209
    • View Profile
Re: Clutch plates
« Reply #28 on: June 30, 2023, 04:57:55 PM »
If the fin washer is missing behind basket could this effect the clutch I can’t remember seeing it
Honda 90ss, Cb250k1 supper sport,
Cb400 four, CB750k7, Cb550, Cb750f2n,
Cb750k2

Offline Trigger

  • Grogu
  • *
  • Posts: 8436
  • Engines built on reputation, not advertising.
    • View Profile
Re: Clutch plates
« Reply #29 on: June 30, 2023, 05:10:16 PM »
I would not know as i have never fitted a clutch without one. It is listed as a thrust washer 90458-506-810  ;)

 

SimplePortal 2.3.5 © 2008-2012, SimplePortal