Would it be wise for me to use the M20 workshop manual as a reference when working on the gearbox on my 1936 Bsa R4, externally it looks identical to my friends M20 ?.
Another question, which of these model series B,or M would my bike come under ?,
service sheets for this bike are just not available.

Vaughan

email (option): vaughanmiles@btinternet.com

Yes to the first bit and you will even find the gears are swappable as shat sizes are the same.

And neither to the second bit, an R is an R.
B & M were designed under the supervision of Val page to rationalize the range thus consigning the R to the dust bins of history.

What is it in ?

email (option): bsansw1@tpg.com.au

Hi Vaughan,

This little green book has quite some useful information on the prewar model including the R-type.

ISBN 0 9502412 7 X , Bruce Main-Smith



Good luck!, Michiel

email (option): vaughanmiles@btinternet.com

What is the best publication to use as a reference on the gearbox, I have got a dissasembled gearbox, not sure if its complete or not.
I should say I cannot find a copy of the BMS book, at a fair price anyway !

Vaughan

email (option): vaughanmiles@btinternet.com

Mercian Motorcycle Manuals are doing reprints of all of the old BSA stuff, right back to the original "book of the BSA "by Waysider

Didn't the R series replace the L series back in the early 30's then got run out by tarting it up as the 1936 Empire Star, along with the also superceded Q which was also run out tarted up as an Empire star to get rid of all of the old engines before replacement with the new design B & M series engines in 1938

email (option): bsansw1@tpg.com.au

The R4 1936, isn't that half an Y13 ?
The foot change gear box is about the same as any M20, so you can check the exploded view on Draganfly motorcycles list don't you think ?

Thanks for the replies guys I,ll follow the lead for Mercian and yes the R4 top end was certainly the same as a Y13.

Vaughan

email (option): vaughanmiles@btinternet.com

The thing that all BSA's engineers openly bitched about is in fact our saviour.
Management would never allow a brand new part to be made where an existing part can be used or modified to do the job which usually meant an engineering compremise.
Add to that the ordenance mentality that all upgraded parts had to be backwards compatiable with the previous parts, we are truely blessed.

And in most cases we can drop the numbers.
They were nothing more then the position of the bike on that years catalogue.
Pre B & M series it was only the letters that were important .
So a Y 12, Y 13 & Y 14 are all the same bike.
As is anything with a G in front of it or a J .


You have a few options
The Book of the BSA volume 7 - 1930 to 1935
The Book of the BSA volume 8 - 1936 to 1939 .
Volumes 1 through 6 all start from 1914 then have extra chapters tacked onto the end.

The BMS "BSA Motorcycles 1935 to 1940" is a reprint of
MotorCycling - Maintenance Series - BSA Motorcycles 1935 to 1940 ( Temple Press)
And this book turns up regularly on evilbay at a reasonable price as their print run dewarfed the BMS print run.
The BMS version has a slightly better index and is printed on thicker glossy paper but the text is identical as is the diagrams & photos.

Both of these are almost direct copies of the Book of the BSA vol 7
So there is no point in chasing up all 4.

Same story for the yearly instruction books .
If there is one for your year, there will be no more detail in it than the books listed above as basically they are all just compilations of the instruction books for the period mentioned in the title.

email (option): bsansw1@tpg.com.au

Trevor,
Thanks for all this information, it certainly points me in the right direction.
Vaughan.

email (option): vaughanmiles@btinternet.com

If you are anywhere near a trade school where they teach motorcycle mechanics, there is a better than average chance the book you need will be in their library.
Most likely only 1 copy now in the reserve section so you will have to photo copy it bey there are only about 10 pages you will need
Although for £ 8 you can have this one
http://www.abebooks.co.uk/servlet/BookDetailsPL?bi=19683495038&searchurl=sortby%3D17%26tn%3DThe%2Bbook%2Bof%2Bthe%2BBSA%26n%3D100121503
Another copy for £ 9
http://www.abebooks.co.uk/servlet/BookDetailsPL?bi=18471789984&searchurl=sortby%3D17%26tn%3DThe%2Bbook%2Bof%2Bthe%2BBSA%26n%3D100121503
or this one for for a tenner
http://www.abebooks.co.uk/servlet/BookDetailsPL?bi=14200384183&searchurl=sortby%3D17%26tn%3DThe%2Bbook%2Bof%2Bthe%2BBSA%26n%3D100121503
or this one if you want the 36 models

There are more if you can be bothered sorting past all the BoyScoutsAmercia stuff that comes up with a BSA search

No more now or I will ruin my reputation of being a grumpy objectionable old bugger

email (option): bsansw1@tpg.com.au