The BSA A7-A10 Forum

Bikes, Pictures, Stories & more => Other BSAs, Other Bikes, Cars, Machinery & Tools => Topic started by: Greybeard on 14.07. 2019 12:10

Title: A10 powered Sunbeam
Post by: Greybeard on 14.07. 2019 12:10
One of the comments on Facebook:
"BSA twin put in sideways !! What a job ! Dnepr twin leading shoe front brake... a marvellous piece of engineering!"
And:
"It's using a Dnepr rear wheel and drive"
Title: Re: A10 powered Sunbeam
Post by: RichardL on 14.07. 2019 13:39
I hate to think about what's involved if you want to make a little tweak to the clutch.

Richard L.
Title: Re: A10 powered Sunbeam
Post by: morris on 14.07. 2019 13:44
That rearward facing cylinder will be difficult to keep cool  *smiley4*
Title: Re: A10 powered Sunbeam
Post by: JulianS on 14.07. 2019 13:59
Seen at the BSAOC Open Day 2016 at Market Harborough.
Title: Re: A10 powered Sunbeam
Post by: Triton Thrasher on 14.07. 2019 14:19
That rearward facing cylinder will be difficult to keep cool  *smiley4

He seems to have got there.
Title: Re: A10 powered Sunbeam
Post by: Swarfcut on 14.07. 2019 16:11
Well I'm well impressed.
 Must have built the bike around the engine and gearbox unit.
 How any access to the timing cover is obtained does not look easy, but I have to admire the clever sandwich plate for that front engine mount.. also the adaptor plate between engine and box.

 Shows attention to detail, finely executed, and on the subject of a recent topic, the breather arrangement takes a starring role....

 Well done.

 Swarfy.

 Additional...The non standard rear drive gear may be a bit more rugged than BSA's original worm gear.
Title: Re: A10 powered Sunbeam
Post by: RDfella on 14.07. 2019 16:25
Great job, but how long will the transmmission last? BSA de-tuned the Sunbeam's meagre output to help make that last.
Title: Re: A10 powered Sunbeam
Post by: Triton Thrasher on 14.07. 2019 17:41
Great job, but how long will the transmmission last? BSA de-tuned the Sunbeam's meagre output to help make that last.


Are you worried about the original worm final drive that’s not on it?
Title: Re: A10 powered Sunbeam
Post by: lawnmowerman on 14.07. 2019 19:02
Bit of a myth about the fragile rear drives on Sunbeams. Martyn Bratby has built a "Fourbeam" and it is coping fine with the staggering power from two Sunbeam engines https://www.youtube.com/watch?v=eB8zRa1SdU0
The problem was that Sunbeam recommended Hypoid gear oil in the rear drive which rots the bronze worm wheel. Castrol D or even Castrol R is much more suitable.

Jim

PS the last time I spoke to Martyn he is planning to upgrade to a "Sixbeam" but it will have a Guzzi rear drive.