Two- and three-bearing singles crankcases

[will_curry]

A post in the 'For Sale' section set me wondering:

viewtopic.php?t=15160

The bike concerned is a 1934 500 single which seems to have a two-bearing crankcase.
I'd thought that by then Ariels had changed over to three-bearing cases.

When and how did Ariel make the change?

[Paul Slootheer]

As far as I know Ariel did change from model year 1936> on from a two to a three main bearing crankshaft and cases. Due to the extra main bearing on the drive side, the drive shaft did also became longer. I’am quite shure Roger knows the exact diff. in lenght…

[Roger Gwynn]

I though that I answered this already or was I only dreaming?
3 bearing cranks arrived in 1935 but not for all models, yes the shaft was longer and numerous other parts had to change but the chain line is the same.

[will_curry]

Paul and Roger, thanks for the info.