Author Topic: LSR BSA  (Read 2662 times)

Offline chaterlea25

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LSR BSA
« on: 05.03. 2025 19:17 »
HI All
This photo of an A7/10 popped up on facebook last evening from the current event at Lake Gairdner in South Australia.
Does anyone know the owner / rider ? Are they members here?
I'm sure we would all love to know how it went on the salt

John
1961 Super Rocket
1963 RGS (ongoing)

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Re: LSR BSA
« Reply #1 on: 05.03. 2025 19:49 »
G'day John.
Looked up the results so far.
Thomas Weitacher 1655 1954 BSA A10 650 M-VG 114.943
Some interesting times set. https://dlra.org.au/2025.htm
Two of my mates are there both around the 170MPH mark.
Cheers
'51 A7 plunger, '57 A7SS racer now a A10CR,  '83 CB1100F, 88 HD FXST, 2000 CBR929RR ex Honda Australia Superbike .
Australia
Muskys Plunger A7

Offline olev

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Re: LSR BSA
« Reply #2 on: 06.03. 2025 07:18 »
The Afflicks seem a wild mob.
129mph on 100cc and 96mph on a 50.
I'll bet that wasn't on pump petrol.
cheers

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Re: LSR BSA
« Reply #3 on: 06.03. 2025 18:23 »
G'day Fellas.
A little more on Thomas. https://www.dlra.org.au/profiles/1655.htm
I never knew what all the classes were for speed trials. Some interesting reading here. https://www.dlra.org.au/class-bike.htm
Cheers
'51 A7 plunger, '57 A7SS racer now a A10CR,  '83 CB1100F, 88 HD FXST, 2000 CBR929RR ex Honda Australia Superbike .
Australia
Muskys Plunger A7

Offline Beeza

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Re: LSR BSA
« Reply #4 on: 06.03. 2025 21:41 »
No hiding from you guys, we’ve been aiming for 120mph and are slowly edging towards it.
For this year we made a huge amount of changes, in weight reduction and wind force reduction, also some carburettor changes, just to name a few.
The bike ran awesome up the salt with everything working very well, soon as I passed through the exit trap and backed it off we had an instant seize/lock up, quite interesting to see how fast you can grab the clutch while it’s sliding/weaving along the salt at 114MPH.
Back home now (Victoria) and after taking off the timing and primary my assessment is piston seizure, the bike won’t be pulled down until I get back to our new home in Queensland.
Our first outing in 2021 ended with a timing side bush unscheduled deconstruction, the second outing to the salt 2023 gave us some good data, but the track was terrible and we went back to the drawing board with a list of changes to make.
Looking forward to next year, I’ll try to keep anyone who’s interested up to date, and may be asking around about how to remove some pistons pretty soon.
The bike is a 1954 road rocket, 201st one built.
Thomas.
62 A10 BVSR, 62 A10 RGS, 53 SFS, 57 G/Flash-black one

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Re: LSR BSA
« Reply #5 on: 07.03. 2025 07:21 »
That's quite some beast. And I see you managed to get hold of some thick flange barrels too!
2 twins, 2 singles, lots of sheep

Offline Beeza

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Re: LSR BSA
« Reply #6 on: 07.03. 2025 10:50 »
Yes Black Sheep, those A10 7fin barrels are rare, the machining for the base studs on that barrel is unique too, it allowed me to open out the barrel stud hole to use 3/8 studs and 12 point 3/8 UNF ARP nuts with high comp washers that matched perfectly, of course the cases were also drilled and tapped to maximum depth 3/8 witworth.
Beast is a pretty good description too, very hard to stop in small test areas, but will accelerate very fast to the rev ceiling of 6500, except in 4th gear, every calculation is for 6500 in top gear to get our target, at the moment we are about 200 RPM short.

62 A10 BVSR, 62 A10 RGS, 53 SFS, 57 G/Flash-black one

Offline chaterlea25

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Re: LSR BSA
« Reply #7 on: 07.03. 2025 11:06 »
Hi Thomas,
It's great to see your BSA competing in LSR *smile*.
What crank and rods are fitted ? Cam and pistons?
Are you running Methanol?

I saw another BSA on the time sheets, a 500
Do you know what model it is?

Apologies for all the questions
John
1961 Super Rocket
1963 RGS (ongoing)

Offline Beeza

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Re: LSR BSA
« Reply #8 on: 07.03. 2025 16:38 »
Hi John, LJ crank heat treated and polished, H beam Map rods, forged 10.5-1 pistons, megacycle 357 cam, gas class so no fuel (methanol).
There was 3 other BSAs, a 500 Goldy, a M20 and a bantam, I know 2 of them and I did meet the young feller that was riding the bantam, great week of racing, just not as good for us this year.
Thomas
62 A10 BVSR, 62 A10 RGS, 53 SFS, 57 G/Flash-black one

Offline chaterlea25

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Re: LSR BSA
« Reply #9 on: 13.03. 2025 22:27 »
Cheers Thomas,
Your BSA is (was) going really well without any exotic modifications
It probably ran lean at the end of the run ? I'm wondering if it has a good enough fuel flow and tank vent?

John
1961 Super Rocket
1963 RGS (ongoing)