58 vs 60 mm crank
right can anyone tell me the difference between a 58 & 60 crank (yeah yeah I know 2).I'm in the market for a new crank,so was wondering as I've only ever used a standard type crank (58 and 107 rod) is it smoother and do you need anything done to the engine casing/mag housing? or is there no noticeable difference
I am playing all the right notes, but not necessarily in the right order.
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rosscla
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It will alter your port timings and squish, you'll gain a few cc and you might need to fit a packer at the base or a different head gasket to get the settings where you want them. It might also be advantageous to consider one with a different rod length and quality, this would give more flexibility, but again you'd need to think about what you're trying to achieve.
Some of them need a groove machining in the casing as the big end of the rod might catch, your piston may touch the casing at BDC.
In relation to vibration, this will depend on the quality and balance of the crank you're considering, again there is a school of thought that says the rod length should be twice the stroke, so 58 / 116 , 60 /120 ought to give less vibration, I think this is something to do with piston acceleration or velocity but that's getting a bit technical for me...someone who knows what they're talking about will surely be along in a minute...
The key thing would be thinking about why you're considering changing and what you expect from your motor and how much your expecting to spend as top quality cranks can get expensive quickly
Some of them need a groove machining in the casing as the big end of the rod might catch, your piston may touch the casing at BDC.
In relation to vibration, this will depend on the quality and balance of the crank you're considering, again there is a school of thought that says the rod length should be twice the stroke, so 58 / 116 , 60 /120 ought to give less vibration, I think this is something to do with piston acceleration or velocity but that's getting a bit technical for me...someone who knows what they're talking about will surely be along in a minute...
The key thing would be thinking about why you're considering changing and what you expect from your motor and how much your expecting to spend as top quality cranks can get expensive quickly
"Our dilemma is that we hate change and love it at the same time; what we really want is for things to remain the same but get better."