Super Jet Stroker in OEM 701

I know someone on here has done this. Or someone has feed back for me. Can I buy a stroker crank, trench the cases, and add a spacer with reasonable performance gains? Or will it be a nightmare. Motor is a 701 Group K ported and b piped, 195 psi, stuffers, reed spacer, mod carbs,flywheel, cdi.......
 

550/440

Maybe I'll get it all the way around NEXT time....
Location
Arizona!
I have no personal experience with this, but that is basically how stroker cranks started, way back in the dirt bike days (and 440 / 550 days). I don't see any issue with it, as long as it's done properly.
 

550/440

Maybe I'll get it all the way around NEXT time....
Location
Arizona!
Early dirt bike days. I'm sure the stroker crank history goes far beyond that...
 
Thanks Blue. ...I appreciate your helpful input. Youve answered my questions in the past also.

Buzzard......Its already fast, just inquiring. Go "licorice" yourself.
 
i wouldnt recomend going that way
if you want a stroker then start from ground and build up
not all strokers req trenching or spacers
like said ya cant just add perf parts and it all work ... you need to find a good combo for it all to work togather
 
Yeah. I figured it couldn't be that easy. Lol. Looks like ill be spending the money on a new pump setup. Just wanted to throw it out there. Always get great input from quality guys. Thanks
 

schicks

Karma Enforcer
Location
West Michigan
what makes it not that easy? on a 62T 701 with stock length rods? 2-6mm should be doable without to much headache
you need to check clearances in the case to crank ( on 4mm+)
you need to determine piston squish which will determine what size spacer you need.
how do you handle port height?

this topic seems to be a very common reoccurring dumb question, that nobody wants to answer.
 
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Blue

Judging your cheapness
Location
St Cloud Florida
Anything over 4mm requires trenching the problem lies in port timing and duration the squish is simple to adjust. Stroker cranks change port duration drastically with ever mm of stroke.
 

schicks

Karma Enforcer
Location
West Michigan
what is the best way to compensate and keep a low port timing? is this done by dropping the sleeve? or custom sleeve? or custom porting to lower? or combination of all?
 

Blue

Judging your cheapness
Location
St Cloud Florida
Combiation of all. 1 change affects another when it comes to port timing. If it was a four stroke u can manipulate the cam to open the valves when u want but in a 2 stroke the valve is the piston as it passes the port window. Thats why it takes a confident engine builder to build a great 2 stroke engine especially a stroker. Stroker cranks not only cause the piston to go up and down farther they also move the piston farther and faster in the cylinder bore with ever degree of crank rotation. This is where the original timing and port duration gets out of wack. The bigger the stroke the worse it gets..
 

Blue

Judging your cheapness
Location
St Cloud Florida
Ur welcome. I wish i could go into more depth but theres more to it than i can text with my phone. Thxz i will clear out some room.
 
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