Stroker Crank Displacement Information

All information on this page based on calculation using stock piston sizes. Connecting rod length information may vary slightly for some types of custom stroker crankshafts that use custom, rather than off-the-shelf, pistons. Stroker calculations on this page based on using 89mm Norton donor crankshaft except where noted.

BSA A65 Stroker

Stock 650cc barrels

SRM 750cc barrels

Rod Length

Displacements:

730cc

830cc

Custom


BSA A10 Stroker

Stock 650cc barrels

No other options

Rod Length

Displacement:

730cc

...

Custom


Norton +4mm Stroke

750cc barrels

850cc barrels

Rod Length

Displacements:

730cc

830cc

stock


Triumph T120/T140

650cc barrels

750cc barrels

830cc barrels

Displacements:

830cc

920cc

6.300-6.050" (see A)


Triumph T100

500cc barrels

No Other Options

No Other Options

Displacement

575cc (see B)

...

5.500" (stock)


(A) 9-bolt barrels made for T120 engines, with a Norton 89mm stroke crankshaft, use 6.300" long connecting rods (centre-to-centre distance). 10-bolt barrels made for T140 engines, with a Norton 89mm stroke crankshaft, use 6.050" long connecting rods. If a 93mm stroke crankshaft is used connecting rod length does not change but position of wrist pin is raised by 2mm.

(B) T100 engines using a modified T120 crankshaft.


Standard Offset Crankshafts

Stroker Crankshafts

Ed G Cranks Home