CB72-77 Racer

G-Man · Post by **G-Man** » Sat Jun 20, 2015 10:30 am

Dave

Well, I count 5 gears so not a standard CB77 'box. Not sure if that woud be a Honda CYB set or a Nova without checking it against the ones I have. Nice to have, though. Most likely Nova if its been used in anger.

G

lloydy1 · Post by **lloydy1** » Sat Jun 20, 2015 10:35 am

G-Man wrote:Dave

Well, I count 5 gears so not a standard CB77 'box. Not sure if that woud be a Honda CYB set or a Nova without checking it against the ones I have. Nice to have, though. Most likely Nova if its been used in anger.

G

Hi G

What do you think the mechanism is on the gear change? Been made up by someone.

Thanks Dave

G-Man · Post by **G-Man** » Sat Jun 20, 2015 11:04 am

Dave

Not seen anything like that. The main part looks CB77 but all those other bits and bobs are custom made or off some other bike.

G

lloydy1 · Post by **lloydy1** » Sun Jun 21, 2015 1:36 am

G-Man wrote:Dave

Not seen anything like that. The main part looks CB77 but all those other bits and bobs are custom made or off some other bike.

G

They are custom made without a doubt. Cant seem to make out what it is doing. It moves a little when changing gear which seemed very stiff to be honest.

Dave

Waveblaster · Post by **Waveblaster** » Sun Jun 21, 2015 10:07 am

I was looking back at the pics of the cam lobes in the top of the head. They seem to be sharp indicating short duration. Not what I would have expected. Perhaps it is just the camera angle.

lloydy1 · Post by **lloydy1** » Sun Jun 21, 2015 12:27 pm

Waveblaster wrote:I was looking back at the pics of the cam lobes in the top of the head. They seem to be sharp indicating short duration. Not what I would have expected. Perhaps it is just the camera angle.

Better pic of the cams.

Talking of cams....Being a novice concerning this engine..How do the cams come out??

The manual I have is pretty feeble concerning in-depth description.

Cheers Dave

G-Man · Post by **G-Man** » Sun Jun 21, 2015 2:50 pm

Lock the cam sprocket (I use a soft aluminium wedge between sprocket and case), then undo that big nut with a flat drift. Usually they are left hand thread....

That releases a taper and allows the cam to be separated from the sprocket. The other half is held with a taper headed drawbar a little like a bicycle steering stem fixing. Slacken the nut at the end of the cam and tap the bolt and you will feel the taper loosen.

With the sprocket released, each cam half is drifted outwards using a soft drift against the cam lobes. Heat the head first to slacken the interference fit on the bearings.

The inner bearing has to be driven out through the outer bearing aperture.

You'll get the hang of it.....

G

lloydy1 wrote:
Waveblaster wrote: Talking of cams....Being a novice concerning this engine..How do the cams come out??

The manual I have is pretty feeble concerning in-depth description.

Cheers Dave