Hello all,

Just joined the pre65 brigade after purchasing an otter framed B40. Is there a service manual available that could give me information such as oil types/quantities, servicing tips etc?

The bike is in good condition but needs a few sessions in the 'Cosmetic department' and a good checking over...any help would be appreciated.

Thanks in advance, Mark.

I use monograde 30 or 40 depending on time of year. Fill it up to the brim, they don't hold much, and even more importantly change the oil regularly. I learnt my lesson the hard way. I had an engine seizure on a road trial and got stranded in the middle of nowhere.

Decent bikes though.

Hi Guys

I would fit an after market oil filter kit,which increases oil capacity and helps with oil cooling, and filtration,

Try Trialsbits.co.uk

Regards Charlie.

Edited February 9, 200719 yr by charlie prescott

FWIW i havent got an additional filter fitted. I use Tesco 20/50 and change it after every 3rd trial along with the gearbox oil and primary case oil. Oils cheap and i have always found that fresh oil is more important than old oil however well filtered.

As you dont know the history of your bike i would flush out the frame as best you can to ensure there is no sludge. Change the oil as regularly as you can afford. Supermarket oil is fine as you will be changeing it regularly. I've fitted a magnetic drain plug in the frame tube bottom drain behind the gearbox along with a magnetic drain plug in the gearbox.

No problems over twelve months of trialing but what you do is up to you. If you do fit a filter make sure it can not restrict the oil feed to the engine as this would cause probable bearing failure as the oil feed on these engines is not the best.

Saying that one of my mates has not got a filter fitted and his engine has not been apart since he built it 15 years ago. He just changes the oil regularly same as me.

There will be some who swear by oil filters and others who swear at them. Same as some swear by monogrades and others swear by multigrades.

As for a manual? Well Rupert Ratios book "Unit single engine manual for BSA C15, B40, B25 & B50" is a bible i swear by. As for the cycle parts well thats just common sense and depends what forks are fitted etc.

They seem to be fairly bullet proof. The only achillies heel as well as with Tiger Cubs is road work as the engine on trials gearing tends to get thrashed for long periods and the oil overheats. Tiger Cub riders were encouraged to ride through every puddle to try to conserve the big end in the good ole days

Enjoy your bike they are great fun but the B40 will never grip as well as the C15. If only it would

Cheers lads....Thanks for all the replies, I'll keep you informed how everything goes.

Thanks again, Mark.