What year CB77 and other questions

Waveblaster · Post by **Waveblaster** » Sun Jan 04, 2015 5:17 am

regarding the fuel cap. That is not standard so I am not sure if it is allowing the air to occupy the tank as the fuel drains. It may be off of a tank that had an external breather. One way to try if you have the time would be to take the bike for the 20 minute spin until it occurs and when it plays up open the fuel cap. If this is the cause it should allow the external pressure to equalise. You could by a reproduction original . https://www.davidsilverspares.com/CB77-305/part_36893/

Regarding the seating position. Given that you are running a single seat perhaps it would be best to move the foot pegs to the back position on the adjustment plate. This would probably offer a more comfortable riding position. I have the standard seat and occasionally move my feet to the passengers pegs for a change as I sometimes feel that my feet are too far forward with the low bars. The brake side should move straight up, the left side will require an extended rod for the gear change. You could get someone to fabricate fairly easily I imagine.

cleg · Post by **cleg** » Sun Jan 04, 2015 9:45 am

What you have there is a 1961 CB72 frame with a 1962 CB77 engine.
The production for CB72's in 1961 were from 10001 through 13443. CB77 frame #'s were 10001 through 11249.
I really like the seat, by the way.

Hoosier Tom · Post by **Hoosier Tom** » Sun Jan 04, 2015 11:27 am

Yes, you have a 1961 CB72 frame titled as a CB77. It's unfortunate you have a CB77 title with a CB72 frame number since it may cause problems if ever inspected for a sale/registration.

HT

sixtiescycle · Post by **sixtiescycle** » Sun Jan 04, 2015 12:09 pm

Hoosier Tom wrote:Yes, you have a 1961 CB72 frame titled as a CB77. It's unfortunate you have a CB77 title with a CB72 frame number since it may cause problems if ever inspected for a sale/registration.

HT

I've encountered this before, DMV is pretty good about one number being off and correcting this. They always seem to have a rough time seeing the numbers when inspecting.

I really like the looks of this bike and it looks like it's a bitsa bike tastefully done with period accessories, Webco pipes (haven't seen those in ages!), CYB seat, New Top A/M chrome front fender that was probably rusty and now painted (been there done that).

There are 6 oil seals under that cover (shift drum, clutch rod, mainshaft, kickstart shaft, crankshaft, and starter sprocket) and anyone of them could cause your leak. I can't tell from the pictures how the breather hose is routed, if it's routed like a later model into the valley under the carbs and the engine has blowby it can also be the "leak".

adangvu1972 · Post by **adangvu1972** » Sun Jan 04, 2015 10:35 pm

Wow! Thanks everyone for the input.

Waveblaster:
Thanks for the link to the replacement cap. I've ordered a replacement gas cap. Meanwhile, I'll go out tomorrow and ride around for 20 mins and see if I run into the same problem and try out your suggestion of opening the gas cap and see if that helps. Also, when I purchased the bike, the previous owner pointed out specifically this tube on the side of the tank that shows the amount of fuel I have in the tank, I'm not sure if that's on everyone's tank but made it sound as though it was special. I took a picture of it here:

gas-tube by adangvu1972, on Flickr

I forgot to mention that the key to the ignition is the same key I use to unlock the gas cap. Not sure if that means anything, but thought I'd mention it.

As for the seating position, I do like the seat, so instead of changing that out, I was thinking maybe a different handle bar that wouldn't be so short and possible come back a little so I don't have to hunch over the tank as much. I like the overall look/stance of the bike now so it's a toss up on changing the seat or handlebars for a more comfortable riding position.

Cleg, Hoosier Tom, Sixtiescycle:
Thanks for figuring out what's going on with my bike. I really like the motorcycle and will go to the DMV an get the title correct. I don't see myself selling it anytime soon or ever, but my only concern would be if having a frame built for a 250cc engine and now carrying a 305cc engine if I'll run into any problems in strength or safety?

Sixtiescycle:
Thanks for the info on the seals, as I'm so new to this world of motorcycles and motorcylce repair, I'll probably leave the seal repair to a professional, but I'll definitely tell the mechanic what you have pointed out. Also, you mention the Webco pipes, I was looking for what type of pipes they were and particularly the heat shields, as one of the heat shield is bent and was wondering if they are custom made or if I can get a replacement. Would you know?

Hoosier Tom · Post by **Hoosier Tom** » Sun Jan 04, 2015 11:28 pm

adangvu1972 wrote:my only concern would be if having a frame built for a 250cc engine and now carrying a 305cc engine if I'll run into any problems in strength or safety?

There will be no problems, they both use the same frame.

HT

G-Man · Post by **G-Man** » Mon Jan 05, 2015 6:22 am

The rear seat mounts and simple cross member (where the rectifier mounts) make it look like a '61. Here is mine....

G