CL / CB / CA Crankshafts - differences

G-Man · Post by **G-Man** » Fri May 28, 2010 5:21 pm

Apart from the obvious 360 / 180 layouts I am interested in which cranks have the little hole in the rotor end of the crank to lube the starter clutch (?).

I have a couple of CL77 cranks with no hole but I also have a NOS C72 crank with no oil hole. My rusty CB77 crank has the hole and I need to source a new crank for that motor. I cannot see where the oil comes from for this hole and wonder why it is not there on the C72 crank. Am I missing something?

G

Wilf · Post by **Wilf** » Fri May 28, 2010 7:03 pm

Oil comes from the right front stud. There is a depression in the block casting that leads to a drilled passage down to behind the starter clutch. The passage is visible when you lift off the cylinder base gasket.

Wilf

teazer · Post by **teazer** » Fri May 28, 2010 10:21 pm

We used to use a CL crank oil seal on our CB racers when we threw out the starter gears etc. And we had to block the hole. My favorite was to use a carb needle - shortened of course. I can't remember how the heck I managed to peen it over like a rivet so it wouldn't fly out.

G-Man · Post by **G-Man** » Sat May 29, 2010 12:12 am

Wilf & Teazer

Thanks for that. I'm still curious why my NOS C72 crank doesn't have the hole. It has an electric starter but no hole. The box is clearly marked with a 259 part number...

G

LOUD MOUSE · Post by **LOUD MOUSE** » Sat May 29, 2010 7:33 am

The oil for that hole comes through the middle of the tapered shaft.
The area ya describe lubes the right side crank bearing.
Could it be the crank the feller has is for the TYPE2 CL72?. ............lm

Wilf wrote:Oil comes from the right front stud. There is a depression in the block casting that leads to a drilled passage down to behind the starter clutch. The passage is visible when you lift off the cylinder base gasket.

Wilf

G-Man · Post by **G-Man** » Sat May 29, 2010 7:37 am

LM

I wondered that but the crank is in a C72 marked box. Maybe some one thought it was C72 and dropped it in there. I'll have to get the diamond burrs out and put a hole in there.

Thanks for the help.

G

LOUD MOUSE · Post by **LOUD MOUSE** » Sat May 29, 2010 8:17 am

Do ya know how to tell the 250 cranks from the 305 cranks?. ............lm

G-Man wrote:LM

I wondered that but the crank is in a C72 marked box. Maybe some one thought it was C72 and dropped it in there. I'll have to get the diamond burrs out and put a hole in there.

Thanks for the help.

G