Hi,

Is it worth getting a crank balanced with pistons and rods if oversize pistons are used?

Does a lightened and knife edged crank make any difference?

thanks
Carnut

Simple reply is if it's a high reving motor YES, otherwise not really.

Shouldn't be too expensive anyway.

its a bird i see, well worth gerrin did of the balancer, drop "holeshot" a line there your way, ask there advice on the crank, but if you get rid of the balancer there's a great lump that can come off the crank too, then of course it would need balancing.

Yes ! I have seen an engine vibrate itself to peices at 9000 rpm because the fly wheel was swapped

How about knife edged and lightened crank?

I assume its dry sumped? If not then I wouldnt spend anything on a longitudinally mounted 'bird personally, especially if its for track use.

I dunno how much that kinda work would cost on the crank but including rebuild costs it could get up to £1k+, and if so it might be worth considering the other options such as dropping in a ZX12 or Busa instead?

Im going to stick with the 'bird engine as its not so unreliable when its dry sumped.

If I were to change to a busa i would also need to change all following

Busa engine circa £3k
Dry sump kit £1k
exhaust £400
power commander £250
Gauges
Prop flange
engine mounts
new pipe work etc etc

Ill also make the bird more reliable by removing the balancers to get better oil feed to the crank.

Yep its OK when dry sumped, just wasnt sure if yours was or not
Obviously if you did swap engines you could offset the costs with the sale of the other engine etc, Im doing it at the moment and its working out quite well having sold the blade and bought the R1 package.

Chris

[Edited on 3/3/05 by ChrisGamlin]

thanks for the advice, it was something I had thought long and hard about.

Ive also thought about selling the car and building a new one, maybe in a few years time

Carnut

Yup me too, but somehow I get more pleasure out of upgrading, especially with the thought of going through SVA etc

Thats what put me off.

If I were to build another I think it would be a track only car.