Crank Question???

[Deesel]

Will an 850 crank case accept a 1000 or 1100 crank shaft?

[Deesel]

Nobody knows if the longer stroke cranks will fit into an 850 crank case?????
Are the bearings a different size, the spacing different or not enough clearance for the stroke??? The 850s, 1000s,and 1100s engines look similar to me(I never really looked close at the 1000 or 1100), are the innards completely different?

[humhead]

This is one of those mods that might seem like a good idea at first, but isn't really practical. There's a 9.6 mm difference in stroke. Even if the crank will fit in the 850 cases, you'll have to change the primary gear the crank or clutch basket (or both). What about connecting rods & pistons? If you use the 1100 crank's rods, you'll have to get custom pistons (larger wrist pin diameter) Next, you'll have to get a spacer for under the block to compensate for the longer stroke.
A better choice would be to look for an 1100 shaftie motor & put it in your 850 frame. Other folks on this forum have done this swap. The only thing that you must change is in the drive shaft area. (I'm not sure what - try the search feature.)

Terry

[Deesel]

Thank you for your input Terry.
I would really like some specifics of exactly what this modification would consist of, if it is even possible.
I understand that swapping cranks is not practical for the average motorcycle enthusiast.

ECR

[Jethro]

You will have to tell us, as I have never seen or heard of this mod in my many years of being on the GSR.