Matt, i have no problem with folk that have limited knowledge, however i do have a problem with people that just dont listen, particularly when the answer i give is not the one that they want to hear.
In answer to your question, yes it is possible to re-balance the crank for the new flywheel, i do this all the time, but its one hell of a job as it involves a complete motor strip to get the crank out. this as you can imagine is way above most budgets. the cost of a balance will be around £400 if weight needs to come off but can be more if weight needs to be added.
the good part of having this done is any energy that is being wasted in the imbalance then comes out in the form of power, the figures i usually see on engines is between 1-2% not much i agree for the road but a lot when racing.
As for adding weight to the cranks, this is done by adding heavy metal. basically, drill a hole (calculated) then fill the hole with tungsten, the tungsten being heavier than steel adds weight and gives a corect balance. to remove weight just drill a hole in the crank web (again calculated). this is all done on a machine that dynamically balances the crankshaft at about 4000 rpm, a bit like a dynamic wheel balance machine.
incedentally, on a crank for a ducati that i recently had balanced it needed metal adding, the cost of the tungsten which was 20mm bar about 30mm long was £400 trade! then the cost of the balance. all well worth it as i had my best results yet with this on the dyno.
I hope this allows more understanding of the subject,
Spike.
In answer to your question, yes it is possible to re-balance the crank for the new flywheel, i do this all the time, but its one hell of a job as it involves a complete motor strip to get the crank out. this as you can imagine is way above most budgets. the cost of a balance will be around £400 if weight needs to come off but can be more if weight needs to be added.
the good part of having this done is any energy that is being wasted in the imbalance then comes out in the form of power, the figures i usually see on engines is between 1-2% not much i agree for the road but a lot when racing.
As for adding weight to the cranks, this is done by adding heavy metal. basically, drill a hole (calculated) then fill the hole with tungsten, the tungsten being heavier than steel adds weight and gives a corect balance. to remove weight just drill a hole in the crank web (again calculated). this is all done on a machine that dynamically balances the crankshaft at about 4000 rpm, a bit like a dynamic wheel balance machine.
incedentally, on a crank for a ducati that i recently had balanced it needed metal adding, the cost of the tungsten which was 20mm bar about 30mm long was £400 trade! then the cost of the balance. all well worth it as i had my best results yet with this on the dyno.
I hope this allows more understanding of the subject,
Spike.
