There are also vintage cranks going back to the early 70s that were welded and stroked. Many of these end up getting worn out from racing use, so keep that in mind if shopping around for used stroker cranks. You would also need to deal with the piston to head clearance as the stroker crank will push the otherwise stock piston/rod set up well out of the holes. Most go with shorter rods, but custom pistons and even spacers between the case and cylinders have been used.
Nothing to be taken lightly. The extra power +/- an extra 100 cc offered by stroking can almost always be made more cost effectively through other means. Quality head porting/matching cam, etc.
Once you reached the limit of bore, 73mm (1080cc motor) on the stock crank, does stroking become a tempting deal when searching for even more displacement. A properly built 1080 is one powerful, and expensive, motor. Just something to consider.
For example, it's been a while since I have heard of anyone doing a stroker on anything less than a big bore (69-73mm pistons, 970 -1080 motor)
Bill Benton's new 915 motor doesn't have a stroker crank, but made 101 rear wheel HP on ... well the race gas version of rocket fuel. Basically 95hp on sane high octane fuel, which is around double the real world rear wheel HP of a very well tuned stock cb750. That's pretty strong power for a cb750 based motor and it isn't even a big, big bore motor. It does however have some very high quality components and porting work done by Mike Rieck.
I'm not trying to discourage you, I love stroker motors, just giving you a little food for thought.
George
