1961 CB72 Project

G-Man · Post by **G-Man** » Sat Apr 18, 2015 2:46 pm

Steve

They come from Japan. Two types, the early riveted one and the later self adhesive one. They come up occasionally so you have to keep looking.

http://buyee.jp/item/yahoo/auction/189309762

You have to sign up for a buyee account and they add on some money for their services but so far I have been very pleased...

G

sarals · Post by **sarals** » Tue Apr 21, 2015 12:10 am

I too like to work alone! I loved your writeup on assembling the pistons into the barrel. Exactly as I did it. There was something very soothing about that, almost like, well, baking. You're right, too, the sound of those pistons gliding up and down in that old barrel was something else - and mine is also STD bore. Getting there, Graham!!

G-Man · Post by **G-Man** » Tue Apr 21, 2015 12:17 am

Sara

Thanks! After my work on the crank it was just comforting to see it together and rotating smoothly. In my early, impatient years, I could pull an engine apart, fix things and have it together in a matter of hours.

Now, I don't need the bike to ride to work on a Monday it's special just to take time and enjoy the ride, so to speak.

How is your 'old girl'? Coming out to play this spring?

G

Steverino · Post by **Steverino** » Tue Apr 21, 2015 1:57 am

It's interesting to see you are inserting the pistons while they are close to parallel to each other. Though they are headed in opposite directions. This may seem a mundane observation but all I've ever done are 360 motors and the pistons have to go in simultaneously and there is no other choice. I also use my fingers to compress the rings. I've broken rings trying to use purpose built tools but I've never broke any by hand.

G-Man · Post by **G-Man** » Tue Apr 21, 2015 2:24 am

Steve

Not mundane at all. It's much easier to do these, but even with a 360 motor I find that you can rock the barrel a little and get alternate rings in from each side. British twins are a little harder as there are no long studs to guide the barrels for you and th eiron barrels are quite heavy.

Because Honda studs never seem to be aligned perfectly there is always a bit of friction between barrel and studs which helps take the weight and lets you get on with sorting the rings out.

G

G-Man · Post by **G-Man** » Sat Apr 25, 2015 2:18 pm

Spent an enjoyable day at the Stafford Classic Bike show today. Not many Hondas on show but one or two bits to buy.

I picked up this speedo with a broken glass but good bezel and then Alan W mentioned that one of our suppliers - Sprockets Unlimited - had a supply of the wide CB72 primary chain material. I had two chains made up for me on the spot and all for less than $50 each. The sideplates are lighter than the original chains but, I'm told, that one of their US customers is sucessfully using them in a race bike.

They also supplied me with a length of 530 chain for this project.

I was mesmerised by the workmanship and ingenuity of this amazing 6 cylinder BSA using two sets of rocket-3 barrels and heads on a custom crankcase. Overhead cams are belt driven and the frame is a modified Rob North type. Unfortunately I did not get to hear it run....

G

SMBH · Post by **SMBH** » Sat Apr 25, 2015 3:14 pm

G-Man wrote:Spent an enjoyable day at the Stafford Classic Bike show today. Not many Hondas on show but one or two bits to buy.

I picked up this speedo with a broken glass but good bezel and then Alan W mentioned that one of our suppliers - Sprockets Unlimited - had a supply of the wide CB72 primary chain material. I had two chains made up for me on the spot and all for less than $50 each. The sideplates are lighter than the original chains but, I'm told, that one of their US customers is sucessfully using them in a race bike.

They also supplied me with a length of 530 chain for this project.

I was mesmerised by the workmanship and ingenuity of this amazing 6 cylinder BSA using two sets of rocket-3 barrels and heads on a custom crankcase. Overhead cams are belt driven and the frame is a modified Rob North type. Unfortunately I did not get to hear it run....

G

I was at Satfford show to day saturday and had a chat to Jeff Dale on the Honda racing motorcycle stand he has a CB77 race kitted on his stand he has a web page hondale.co.uk, I was talking about the Honda primary chain and he tells me the Messerchmitt 3 wheeler use the same chain. I had same chain from Sprockets Unlimited and have done some 500 miles with no problem.
Good find that speedo, not much stuff for CB72/77 there today.
But a good show.