honda305 Home honda305 Auctions honda305 Gallery honda305 Forum


honda305.com Forum

Login
□ Search
□ FAQ 
□ 
Vintage Honda Owners,
Restorers, Riders and
Admirers

66 CA77 Kick start seems to slip.

Clutch, Transmission, Drive Chain, Sprockets
Aussieken272
honda305.com Member
Posts: 4
Joined: Thu Nov 22, 2018 4:59 am
Location: Griffith NSW Australia

66 CA77 Kick start seems to slip.

Post by Aussieken272 » Thu Nov 22, 2018 5:19 am

Just purchased this bike from apparently a very diligent person of vast experience. Bike hasnt gone for a few years. has a genuine 10,000 miles on it and all original with panniers.
clutch is not disengaging and im fine to deal with with a rolling start and accelerate decelerate with clutch in to fix. Just running standard motor oil of 20 50 i think.
concern is when i use kick starter, it seems to not be direct to crankshaft and has slippage. It feels to me that the effort of the kick start passes through the clutch and the slippage is occurring in clutch. However from my experience, i feel it does not pass drive through the clutch. Im a former car mechanic but not a bike mechanic.

Any help for this new member

garage of bikes
1928 J 1000 harley outfit
2 Honda 1979 XL500s
CA77 Honda 1966
1981 Honda XR 500
harley 1938 WLDR
Norton commando 1071 850
triumph T150 1971
Harley 1994 FXDWG
Harley FXR 1995
Suzuki GS 750
Honda 7/70 CB750 (genuine 5000 miles)
Kawasaki 1977 Z1000
KTM 525
Various others to clog garage
Wanted Bridgestone 90 deluxe or similar

e3steve
h305 Moderator
Posts: 2601
Joined: Fri Oct 31, 2003 1:38 pm
Location: Mallorca, Spain & Warsash, UK

Post by e3steve » Thu Nov 22, 2018 8:56 am

Is the slippage sudden? Or is it like it’s, as you say, ‘slipping’.

These bikes do suffer badly from k/s pawl wear...

DJM
honda305.com Member
Posts: 553
Joined: Thu Oct 09, 2003 1:54 pm
Location: Chesterfield UK

Kickstart / clutch slippage

Post by DJM » Thu Nov 22, 2018 9:30 am

The 'drive' from the kickstart lever to the crankshaft DOES pass through the clutch on this bike (and most others) so what you are describing could well be like clutch slip, even if drives OK while on the road.

They do also suffer from wear in the pawls but this would be a sudden collapse of the pedal rather than a gradual slippage if the problem is in the clutch. At 10,000 miles I wouldn't expect the pawls to be badly worn.

Changing to an old fashioned straight SAE 30 grade oil (if you find some) might help but I wouldn't count on it. maybe you should just give the clutch a quick strip and give the plates a good clean and see if this helps, not a difficult job. Could just be a warped plate which may be obvious when you get it stripped down.

User avatar
G-Man
honda305.com Member
Posts: 5678
Joined: Wed Mar 25, 2009 5:17 pm
Location: Derby, UK
Contact:

Re: Kickstart / clutch slippage

Post by G-Man » Thu Nov 22, 2018 11:38 am

If the clutch doesn't disengage (and won't free up) it is unlikely that is is causing the kickstart to slip.

The kickstart knuckle that connects the kickstart lever to the splined kickstart shaft (inside the right cover) has a bit of a design flaw wher the square end of a slot concides with the "V" grooves of the spline. This causes it to crack and split open. This means that the knuckle slips on the spline. Pretty much every CA72/77 and CL72/77 will have a crack in this part by now and some have actually spung open, causing it to slip.

Image

I drll a hole at the end of the crack to stop the crack then weld it up.

Image

This is the welded crack before re-machining.


G
Image

G

DJM wrote:The 'drive' from the kickstart lever to the crankshaft DOES pass through the clutch on this bike (and most others) so what you are describing could well be like clutch slip, even if drives OK while on the road.

They do also suffer from wear in the pawls but this would be a sudden collapse of the pedal rather than a gradual slippage if the problem is in the clutch. At 10,000 miles I wouldn't expect the pawls to be badly worn.

Changing to an old fashioned straight SAE 30 grade oil (if you find some) might help but I wouldn't count on it. maybe you should just give the clutch a quick strip and give the plates a good clean and see if this helps, not a difficult job. Could just be a warped plate which may be obvious when you get it stripped down.
'60 C77 '60 C72 '62 C72 Dream '63 CL72
'61 CB72 '64 CB77 '65 CB160
'66 Matchless 350 '67 CL77
'67 S90 '77 CB400F

Aussieken272
honda305.com Member
Posts: 4
Joined: Thu Nov 22, 2018 4:59 am
Location: Griffith NSW Australia

Re: Kickstart / clutch slippage

Post by Aussieken272 » Thu Nov 22, 2018 8:12 pm

DJM wrote:The 'drive' from the kickstart lever to the crankshaft DOES pass through the clutch on this bike (and most others) so what you are describing could well be like clutch slip, even if drives OK while on the road.

They do also suffer from wear in the pawls but this would be a sudden collapse of the pedal rather than a gradual slippage if the problem is in the clutch. At 10,000 miles I wouldn't expect the pawls to be badly worn.

Changing to an old fashioned straight SAE 30 grade oil (if you find some) might help but I wouldn't count on it. maybe you should just give the clutch a quick strip and give the plates a good clean and see if this helps, not a difficult job. Could just be a warped plate which may be obvious when you get it stripped down.
you guys are amazing and thanks to G man too. such quality responses of knowledge. I have a good supply of older type oils but most are still a multi-grade. Back in the 70's and 80's I was in charge of all machinery service on our farms and we used sae30 grade for everything. I will get the bike registered today or tomorrow and go for a ride tomorrow and see if I can find a more conclusive issue. It does feel like the clutch is slipping when kicking and it is intermittent. So each kick will differ from no slip to some. I feel G man response would provide a constant slip and I trust it is not so serious. But if its slipping a little on kicking then it may easily slip under load and fail? I am hearing calls to slip the clutch out and wash it. Kero or petrol?

User avatar
G-Man
honda305.com Member
Posts: 5678
Joined: Wed Mar 25, 2009 5:17 pm
Location: Derby, UK
Contact:

Re: Kickstart / clutch slippage

Post by G-Man » Fri Nov 23, 2018 3:07 am

If it is intermittent then it may be the pawl inside the kickstart ratchet.

Can you hear anything when it slips?

Any solvent would do on the clutch plates. I usually put them in an ultrasonic bath which reall pulls the crud out of them.

G
Aussieken272 wrote:
DJM wrote:The 'drive' from the kickstart lever to the crankshaft DOES pass through the clutch on this bike (and most others) so what you are describing could well be like clutch slip, even if drives OK while on the road.

They do also suffer from wear in the pawls but this would be a sudden collapse of the pedal rather than a gradual slippage if the problem is in the clutch. At 10,000 miles I wouldn't expect the pawls to be badly worn.

Changing to an old fashioned straight SAE 30 grade oil (if you find some) might help but I wouldn't count on it. maybe you should just give the clutch a quick strip and give the plates a good clean and see if this helps, not a difficult job. Could just be a warped plate which may be obvious when you get it stripped down.
you guys are amazing and thanks to G man too. such quality responses of knowledge. I have a good supply of older type oils but most are still a multi-grade. Back in the 70's and 80's I was in charge of all machinery service on our farms and we used sae30 grade for everything. I will get the bike registered today or tomorrow and go for a ride tomorrow and see if I can find a more conclusive issue. It does feel like the clutch is slipping when kicking and it is intermittent. So each kick will differ from no slip to some. I feel G man response would provide a constant slip and I trust it is not so serious. But if its slipping a little on kicking then it may easily slip under load and fail? I am hearing calls to slip the clutch out and wash it. Kero or petrol?
'60 C77 '60 C72 '62 C72 Dream '63 CL72
'61 CB72 '64 CB77 '65 CB160
'66 Matchless 350 '67 CL77
'67 S90 '77 CB400F

Aussieken272
honda305.com Member
Posts: 4
Joined: Thu Nov 22, 2018 4:59 am
Location: Griffith NSW Australia

Re: Kickstart / clutch slippage

Post by Aussieken272 » Fri Nov 23, 2018 4:03 am

G-Man wrote:If it is intermittent then it may be the pawl inside the kickstart ratchet.

Can you hear anything when it slips?

Any solvent would do on the clutch plates. I usually put them in an ultrasonic bath which reall pulls the crud out of them.

G
Well i got her registered on club plates and will try her tomorrow. the slipping as you force down on kick starter reveals no feed back indicating a pawl slipping. no noise. it feels to me as if the clutch is slipping. Maybe i had my lever in at the time? But all bikes ive ever experienced dont have a difference on kicking with clutch either in or out. Indicating to me there is no transmission of effort through the plates. My 28 harley however does need the clutch engaged as the kick start is direct to gearbox. Some one did say above that its common that the effort goes through the clutch. but in this bike and not looking at diagrams, i feel the effort does transmit through the clutch. in which case i need to be careful not allow much slippage in trying to get it going tomorrow and last resort is pull it apart and clean. thank you for your help gentleman.

Post Reply




 

CB-77 | CYP-77 | Road Test | Riding Log | Literature | Zen | Marketplace | VJ Survey | Links | Home