85 super stroker

[2 strokes for life]

Wouls it be possible to take the conecting rod out of a 125 into a 85 and then make a spacer plate that would support the change. If it was any what so possible this would make for one fun woods bike. Also is you used a 125 or 250 head, jug, piston, rings, and connecting rod would i be able to machine the the jug to fit the 85 bottom end. I am just pondering on these. Tell me what you think.

 

[jason33]

jug/ head- no not likely
good luck finding a rod with the same pin diameter on the crank-also the bottom dead center of the rod might hit the cases
but yea its possible-
aka--- banshee- and a few others have been done-
basically the timing would be the same-,or you might need a shorter/ taller piston height-
but the crank stroke will remane the same unless the crank is re drilled (stroked crank)

its not as hard as a 4 stroker with a timing gear syncronisation =longer timing chain
different cam gear to keep it in time through the strokes
--
mabe you could have machine work done to the flyweights on the crank- to add weight- then put in a big bore to even out the vibration- this would be easier

 

[hot125mod]

thats not a stroker it is a long rod no it wont work. dont waste your time

 

[95xr250]

ya the rod would smack the clinder and the jug is to short and you would have to be one heck of a machinest to make that jug

 

[2 strokes for life]

I was thinking of making a spacer plate for it.

 

[derek the 2 stroke]

your stroke would be the same lenth because the crankshaft would still make have the same space to rotate,you would have to mess with the crank to not just the rod and the head wouldnt work either its probly too wide

 

[2 strokes for life]

derek the 2 stroke, you would be suprised what you can do with your mind set to it. I think i am going to try it.

 

[derek the 2 stroke]

you probably can im just sayin that aint gonna be easy but you do have to machine the crank for a longer stroke.
good luck


Let us know how it goes.

 

[2 strokes for life]

derek the 2 stroke, i will keep you posted. This is going to be my winter project this year.

 

[OldTimer]

Seems to me if you're going to take on a project like that, you should try just sticking an entire 125 motor in an 85 frame because sticking a 125 connecting rod in won't do anything to increase stroke and you would basically spend the winter working to accomplish zilche.
BTW - Honda has a 250Jr which squeezes a 250 4T motor into an 85 frame. I would love to have one of those!!!!

 

[derek the 2 stroke]

it says in motocrosss action magazine,"stroking involves moving the crank pin location."SO you have to get that done but making the 125 head fit will be hard to do.Ill try to come up with some ideas.I think you should probly just bore a 85s cylinder over to 124CCs

 

[2 strokes for life]

derek the 2 stroke, i found a 1978 Yamaha YZ100 today for $25. It needs an engine and my IT175 should almost slip right in it. So, i might but another IT175 engine and through that in the bike and have a mini racing machine that is vintage.

 

[SteveinSpringHill]

Moving the cylinder would call for relocation of the pipe, would the mounts still line up? Would the pipe fit in the frame?

 

[2 strokes for life]

SteveinSpringHill, it looks almost like the 79 Yamaha IT175 frame is the same as the YZ10o but with bigger tires and suspension. I might be able to bolt it stright in. As for the pipe i do not know yet.