BSA A10 oil

[Brown975]

Hi all,

I'm new to this forum but have owned my lovely 1960 A10 golden flash matching numbers bike for a few years now.
Im looking to give it a dam good freshen up and service.

What engine and gearbox oil should i use? Also, what oil filter maintenance is needed? Ie. Are they gauze washable items?

Will be visiting the amal website for a carb rebuild kit too as my jets are a bit iffy.

Any help would be appreciated.

Regards,

Adam.

[Bess]

Hi,

   Engine - if you have a preference for synthetic 15W-50 part synthetic although 20W-50 traditional will be fine for long term use. (BSA have a service sheet discussing changing to detergent oils)
   Gearbox - 90 hydraulic oil although SAE 50 traditional will be fine.
   Forks and primary - SAE 20 fork oil (better for anti foam) or you may get away with a 46/68 hydraulic oil at a push.

Worth a read:

http://www.realclassic.co.uk/techfiles/oil030319.html

Best wishes...

[JulianS]

I use Morris 20/50 in the engine, Morris 20 in the primary chaincase and forks and Halfords 80/90 EP GL4 gear oil in the gearbox.

I also use a return line after market  filter.

There is a mesh filter in the oil tank, there should be a mesh filter in the sump and another on the pressure relief valve. These are metal and should be cleaned when oil changed, in petrol or parafin or whatever you use to clean engine parts.

[Bess]

Hi,
     The BSA service sheet mentioning the use of detergent oils.

Best wishes...

[Brown975]

Hi all,

In my hayned BSA owners manual, it suggests to use castrol 20/50 for engine, gearbox and primary chain case. Is this suitable?

I was a bit iffy on using the 20/50 in the gearbox!

Regards, Adam

[Bess]

Hi Brown975,
                       This is worth a read:

http://www.realclassic.co.uk/techfiles/oil030319.html

20W-50 traditional will be fine for the engine.

With modern advances, a gear oil for the gearbox say a 90 hydraulic oil or as Julian says 80/90 EP GL4 gear oil (gear oil between 80-90 is fine). Primary a SAE 20 seems to be the consensuses, you can use SAE 20 fork oil for its anti foaming properties.

Best wishes...

[JulianS]

Haynes was written in 1973 and the oil recommendations have not been updated in that manual.

In the past 44 years oils have advance significantly, as has owner experience.

 If you read all the various older books you would see, from BSA itself, that engine oil was the stuff to use in the primary chaincase and that 20 was the stuff to use in the primary chaincase, and that they did not recommend multigrade in either the gearbox or the primary chaincase, then later with the B50 which breathed intothe primary case and shared the common multigrade oil.

Read too much older info and it gets confusing.

It is worth viewing the Morris oils wedsite on classic engine and gearbox oils.

https://www.morrislubricants.co.uk/products/classsteam/classic-engine-oils.html

Read the recent information and make your choice is my advice.