Author Topic: Which camshaft & crank do I have?  (Read 730 times)

Offline iansoady

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Which camshaft & crank do I have?
« on: 10.09. 2011 16:40 »
I have the head & barrel off my 1961 Golden Flash as I have a couple of fins to weld and my dodgy knee precludes riding at the moment *sad2*

I know this engine should have the later (big journal?) crank and sports (356?) cam but am not sure what I actually have. I know I do have thin flange barrels which isn't right.....

Just to satisfy my idle curiosity, how can I tell which crank & camshaft I have without further dismantling?
1962 Golden Flash (arrived)
1955 Velo Viper/Venom (departed)
2004 Triumph Tiger 955i (staying)

Online bsa-bill

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Re: Which camshaft & crank do I have?
« Reply #1 on: 10.09. 2011 17:32 »
I'd be interested to know how you can identify them without a partial strip down.
Not too big a job to lift head and barrels and peer down onto the crank though.
For the cam, if someone could measure the lift on the cams, you could mark a pushrod and determine it's travel. I have a 356 cam spare I'll see what I can do tomorrow
All the best - Bill
1961 Flash - stock, reliable, steady, fantastic for shopping
1959 Rocket Gold Flash - blinged and tarted up  would have seizure if taken to  Tesco

Online RichardL

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Re: Which camshaft & crank do I have?
« Reply #2 on: 10.09. 2011 22:11 »
Cam profiles available somewhere here as a graph. 

As for the crank,  maybe best to satisfy your curiosity when the need comes to get in there.  To my recollection there is no view to the journals through the sump plate,  but maybe someone will know if one could ID the crank from any markings or details on the outside of the flywheel.

Richard L.
Plan on signing up for the world-wide 2020 DISTINGUISHED GENTLEMAN'S RIDEon September 27, 2020. This year it's a solo or pillion ride in dapper attire. Watch website at for details.

Offline KiwiGF

  • Last had an A10 in 1976, in 2011 it was time for my 2nd one. It was the project from HELL (but I learned a lot....)
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Re: Which camshaft & crank do I have?
« Reply #3 on: 11.09. 2011 02:17 »
I think the LJ crank flywheel has bolts on the circumference ie radially and SJ are bolted axially ie inside the flywheel difficult to describe in words

Heres an LJ

No doubt someone will correct me if I've got that wrong

New Zealand

1956 A10 Golden Flash  (1st finished project)
1949 B31 rigid “400cc”  (2nd finished project)
1968 B44 Victor Special (3rd finished project)
2001 GL1800 Goldwing, well, the wife likes it
2007 KTM 950 Adventure, cos it’s 100% nuts

Offline terryk

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Re: Which camshaft & crank do I have?
« Reply #4 on: 11.09. 2011 09:12 »
yeh thats right KiwiGF
1950-53 A10 rigid/plungers, 1958-61 A10 super rockets, 1947-50 A7 longstrokes, 1949 Star twin,
1951-54 A7 plungers, 1940s M21, WDM20s,
1948-50s B33s rigid/plunger/swingarm, 1948-50s b31s rigid/plunger/swingarm