Hi all

I was wondering if anyone has experience of running older B25 cams with newer crankshafts.

Camshafts can have up to three timing marks and RR recommends use of the "V" mark if one is present. This mark appears to be two teeth anticlockwise from the straight "I" timing mark with the third "." two teeth clockwise from the "I" mark. I assume that these three marks relate to the different models and years where the same camshaft was used but different amounts of advance/retard was used???

The camshafts I have have the single "I" mark, so my question is, can I retime the camshaft two teeth anticlockwise to coincide with the "V" location on my earlier cam???

Secondly, the engine I am rebuilding has a later crankshaft in ( lefthand flywheel drilled for timing plunger, after 69??), are there any differences between the later and earlier type crankshafts ie was the location of the woodruff key for the timing pinion moved in relation to TDC.

Hope this all makes sense.

Any info would be greatly appreciated.

Regards

Rob

Hello,

I'm new to this forum and I'm considering acquiring an M21 circa 1954 with a plunger frame. Perhaps it's lunacy but it's for nostalgic reasons. My first bike was an M21 which I bought when I was about fourteen and I'm now sixty nine. It had a sidecar frame with a wooden box and cost me £16. For a number of years it was used around our dairy farm as a general workhorse until we broke a valve lifter when doing some overdue maintenance. We didn't know where to get a replacement lifter from and so it was put in the back of the workshop. Various bits and pieces were subsequently robbed from it and eventually it went to the scrap man. How I regret that now!

My question is how available are parts for the M21 please?

My incomplete list is in no particular order:

Carburettor and fuel line
Exhaust
Headlight
Speedometer
Foot rests
Kick start lever
Front brake lever
Front brake cable
Tank badges
Oil tank cap
Battery cover?
Cover from other side to battery?
Primary chain case bolts and inspection cover
Possibly the engine drive sprocket
Rear light
Drive chain
Possible holes in the fuel tank
De-compresser lever and cable
Advance/retard lever and cable
Parts book
Owners hand book and/or workshop manual

I shall be most grateful for info or comments. Thank you.

I made a similar frame with plate for my B44 which picks up on the oil tank and upper toolbox mountings.

Hi
This is my first post on this fantastic forum .
I have read for many years and really enjoyed the post.
I wonder if someone could help me please i have a 1957 Rocket .
It has a stamp on the engine case just above the oil pressure valve which is RS its properly stamped
Also it has the same RS  stamp on the underside of the gearbox ?.
I have tried to fined info but no joy .
Any help would be very much appreciated .
All the very best to you all .

Hi Can somebody tell me the  measurement to adjust the center nut on a single spring clutch on  a 1931 B31-2 . Is it trial and error , or is there a set amount the spring is compressed. Thanks