Boring worn/old engines

[Jamiyjames]

Ok I'm looking at getting an old bike to start doing some track days here and there, and for the price in looking I know I'll probably see some shocking bikes,, however if I see one I like and the engine needs some work I might consider it, so my question is if I needed to overhaul an engine and decided to bore it out 1) would it be expensive? Or would it be cheaper to buy a near new bike? 2) if it was bored out I would assume it would need a new sized piston to create a proper seal? 3) is there any things to consider if I went ahead with boring the engine, like bore stroke ratio, insurance (as is be riding it to the track most likely) eligibility to get on the track, higher torque /top end power etc?

And if you have any Experience with this please could you share?

Thanks :-)

[Jamiyjames]

well if that's because its a lot of hassle then that doesn't bother me its the financial cost that bothers me the most.