I've got an engine rebuild coming soon. I know that the difference between the 6m and 7m crankshaft is the extra counterweight. I was wondering if it was worth the trouble of finding one and replacing my 6m.
6m and 7m crank
- Thread starter casper35404
- Start date
Agreed. If you are really worried about it, get your engine balanced - likely cheaper and faster than trying to find a 7M crank.Jeff Lange said:
If you have a good condition 6m crank by all means use it if it's trashed you can try to find a 7m one, not sure about there but they're not all that common here.
I went with a 7m crank for the new motor as from a structual point of view it makes more sense to me being an even construction along it's length.
I think/feel being so long the 6m crank may be subject to end to end "whip" (this is what the balancer on the front attempts to cancel out) with the cranks throws without the extra counterweights being a focal point as there isn't as much material there.
I hope this rambling makes sense as to why I went 7m.
I went with a 7m crank for the new motor as from a structual point of view it makes more sense to me being an even construction along it's length.
I think/feel being so long the 6m crank may be subject to end to end "whip" (this is what the balancer on the front attempts to cancel out) with the cranks throws without the extra counterweights being a focal point as there isn't as much material there.
I hope this rambling makes sense as to why I went 7m.