1961 CB72 Project

sixtiescycle · Post by **sixtiescycle** » Sun May 10, 2015 2:08 pm

Graham,

Very nice!

Back in '92 when I had to have another CL77, the one I ended up with needed a shock cover. No ebay, no computer, you were searching classifieds, boneyards, and word of mouth for parts. I took a piece of 2" exhaust pipe cut to the length of the cover and welded a big ass washer at the top. Ground up the weld, painted it and it's still on the bike today. No one knew the difference. Nice to know the Girlings work as replacements..

Thanks for the offer of help with the shocks. If I have questions I'll let you know. Would like to get that bike done sometime soon!

G-Man · Post by **G-Man** » Sun May 10, 2015 2:25 pm

Dick

That's fantastic! There's nothing better than a neat ingenious solution to a problem. I saw a Moto Guzzi project where the speedo and revcounter mountings were made from stainless steel cream jugs. I love stuff like that.

My CB400F ran for years with the rectifier from a Lucas car alternator soldered on to the original Honda connector. It was a fraction of the price of a Honda part with a better spec.....

I'm going to make some more durable covers for my early CB72 shocks out of some lengths of aluminum tube...

G

sixtiescycle wrote:Graham,

Very nice!

Back in '92 when I had to have another CL77, the one I ended up with needed a shock cover. No ebay, no computer, you were searching classifieds, boneyards, and word of mouth for parts. I took a piece of 2" exhaust pipe cut to the length of the cover and welded a big ass washer at the top. Ground up the weld, painted it and it's still on the bike today. No one knew the difference. Nice to know the Girlings work as replacements..

Thanks for the offer of help with the shocks. If I have questions I'll let you know. Would like to get that bike done sometime soon!

sixtiescycle · Post by **sixtiescycle** » Sun May 10, 2015 3:22 pm

Looking at those aluminum covers on the '61 CB72 Kevin got at the swapmeet they look like they could be a little thicker. On the drive side of that bike it looks like it lost a chain at some point and with the size of that sprocket it got the covers and ripped them. That's another thing I wanted for years and recently acquired, a tig welder. My Company closed one of it's subsidiaries where I worked for years, auctioned off the equipment and I was able to get it very reasonably. Very low hrs on it and works great!

G-Man · Post by **G-Man** » Sun May 10, 2015 3:41 pm

You're making me jealous now..... :-)

Is that an AC machine? Incredibly expensive unless you take a gamble on eBay.

Yes the lower covers are ridiculously thin, for no good reason. If the chain doesn't get them the spring wears through in no time.

The weight saving is cancelled out by the fact that the preload adjusters and top collets are steel. It was just a stupid piece of design. At least Honda realised it very quickly.

G

sixtiescycle wrote:Looking at those aluminum covers on the '61 CB72 Kevin got at the swapmeet they look like they could be a little thicker. On the drive side of that bike it looks like it lost a chain at some point and with the size of that sprocket it got the covers and ripped them. That's another thing I wanted for years and recently acquired, a tig welder. My Company closed one of it's subsidiaries where I worked for years, auctioned off the equipment and I was able to get it very reasonably. Very low hrs on it and works great!

sixtiescycle · Post by **sixtiescycle** » Sun May 10, 2015 4:04 pm

Yes, AC/DC, I can do aluminum, stainless etc. Also doubles as a stick machine, 175 amp Lincoln. Small but should do anything I need. The nice thing about it was I knew it's history. We had a 275 amp machine which was used all the time so this one just sat unused. It hasn't paid for itself yet but close! : )

G-Man · Post by **G-Man** » Sat May 16, 2015 5:48 am

I Just unpacked this NOS early crankcase cover and it seems a little unusual compared with the ones I have seen for '61 engines. This one is un-numbered.

It has the breather tower at the back.

It has oil drillings at the right hand main bearing location to accommodate both ball and roller type bearings. (on the left in this picture)

And the barrel mounting face is designed for the later type barrel, with lube feeds for both options.

It seems almost like some kind of universal replacement but perhaps just the last type of breather tower crankcase? Does anyone else have anything like this? I'm tempted to use it in my CYB72 engine unless there's something special about it.

G

G-Man · Post by **G-Man** » Sat May 16, 2015 8:00 am

It's like Christmas morning here in my hotel. I've been opening my eBay 'presents'. So much nicer than Christmas as the surprises are all good ones....... :-)

A fresh set of spare tank badges from Ray Byrne. The '61 CB72 got the badges intended for my 1960 Dream so these are going in the spares box for that project.

After all my crank work, I thought I would try out some better oil filtration.

I've already built up a good oil pump for this project but couldn't resist this early style NOS pump. Later ones had the engine mount built in as per CL72/77. This one had a CL72 partnumber on it so was probably supplied in error back in teh day and put back in th ewrong bag.....

Here are the pristine insides with all those nasty sharp corners to cause cavitation and disrupt the oil flow...... :-)

I get a second 'Christmas' later this weekend when I pick up some more parts from my friend's house.

G