My bike was built under contract S1048. However, I'm using the Parts book dated 1940.

The length of the clutch pushrod PN# 66-3790 is listed as 12.435 inches long.

Another parts book lists 15-4261 as the pushrod part number.

I have 2 clutch pushrods, one measuring just about 12.75 inches long. The other is just a shade over 13" long. Both are 1/4 inch diameter.

So........ What's what here? Another weeeze by BSA?

Thanks in advance for your help.

email (option): britool51@hotmail.com

Hi Robb,

The repop sold by Russell are 12 3/4 inches.

Hi Robb..I make each pushrod up individually to suit the individual bike and find slight variations in length are the result...A standard length of silver steel, in the UK at least, is 13" long...so finding anything longer than that would be unusual.(and not usually required)
The standard length for the pushrod as detailed in the standards for the M20 is 12.740"~12.750"...Ian

email (option): ian@wright52.plus.com

SPLENDID! Thanks to both of you.

Ian, over here we do not have "silver" steel. So,
what would be a substitute? We do have drill rod
that is called O1 (oil hard). That's Oh One.

I do believe this part must be hardened as it takes a lot of use. It really would be easy to make.

email (option): britool51@hotmail.com

Hi Robb... 'Drill rod' is the American equivalent. Cut the rod to length and then heat each end slowly to red and quench in cold water. Clean off the ends with some emery cloth until they are shiny and then heat until the colour is 'pale straw'..a pale yellow..quench immediately again in cold water.
If the material goes too dark at the tempering stage it can be reheated and the whole process repeated.
It does NOT need to be quenched in oil...At small cross sections the material is hardened and tempered using a water quench.
It is when the material is in larger sections that an oil quench is used..the problem then is that a water quench will cool the outside surfaces more quickly than the core resulting in cracking or 'spalling' of the surface. Oil slows down the initial cooling of the surface...Ian

email (option): ian@wright52.plus.com