CB72 Vintage Racer

[jerry]

Dear Jensen, I wonder what became of the bikes he built. Are they still involved in racing? All the best Jerry

[jensey]

Hi jerry,

The 5 speed primary gear driven bike was for sale a few years ago,
I saw it (and touched it), and saw how the engines were build.

I also noticed that he build and used his own designed and made cam followers with a bearing were it touches the cam. I don't know if he made his own cams.

I think he used cranks, build up from CB450 and CB72, I saw he did change the stroke by having and off axis big end pin.

He never took notes of what he was doing, no drawings, no nothing.

It's said that all that knowledge is gone,

jensen

[jerry]

Dear Jensen, I suppose all things come to an end eventually. Even I sold the 2 race Bikes in June. All the best Jerry

[GORDON BROWN]

Hello everyone

Jensey, I think it was George Flick's bike that had a extra lever on the L/H bar to engage gear, it was back in the old push start days and he just pushed the bike in neutral ( a lot less drag) then just "dropped" it into gear once moving, simple but clever !

The pictures below are,
1) The cam chain tensioner setup I had used, steel centre roller made by a friend and a toothed type tensioner ( CB450 or Kawasaki ? cant remember )
2) A gear drive setup from a article in Clubman magazine.
I think I should give the slipper idea another try as it looks a lot simpler than the above.

Back to the workshop then.

Gordon
SAFOJ

[G-Man]

Gordon

Thanks for posting those. The gear drive looks good. Are those oil pump gears top and bottom or specials?

G

[GORDON BROWN]

Hello

G-Man, the gears are a conversion to replace the filter drive chain, it was supplied by Dennis Murfin / Peter Maddox who ran M&M racing. They also supplied the vernier cam sprocket in the picture along with the ASSO 350 pistons, O.S. valves and other parts.
Dennis still advertises in the VJMC magazine but I dont know what he still has available.
I dont know if the filter chains had given any problems but it does mean you can get the filter in and out easier.

Stan, finaly got a look at your photobucket stuff, great workshop and racing shots. Hope you enjoy getting the 72 back out on track, what are the cut off dates for the class you will run it in and are they generaly competive in the class ?

Gordon

SAFOJ

[Airmun]

Hello Gordon. Was Dennis also the maker of the gear cam drive?