Sensible:
Taking a wild guess I'd say his license is still restricted & he wants it to "look" legal but have more power.
That said, a gradual increase in power seems emminently sensible compared to 2 years on 33bhp & bang! straight up to 100+.
Kawasaki:
Yes - larger holes will give less restriction. Roughly the power should increase with the hole area, i.e. with the square of the diameter. So if you make the hole twice as large, the power will be four times higher. If you want say, 66bhp instead of 33, the hole needs to be about 1.41 times larger.
You'll need to keep the hole very circular & very concentric, and also need to
Do us a favour & upload a good quality picture of the washer - particularly noting if the hole has been "sharpened". Measure its diameter before & after, & note the difference in top speed.
It would be much more sensible to make up a 2nd set of restrictors - that way if you cock up making the holes you can have another go & still ride your bike in the mean time.
I do have a lathe & if you give me enough information I could possibly make you some - tho' not for a week or two as I'm recovering from a shoulder operation.
A point of caution:
If the police suspect your bike is illegal & inspect it, they will have seen more than enough restricted bikes to spot that the holes are larger than usual, will dyno test it, & plonk you into a world of fines & bans. And I suspect that because it would invalidate your insurance they would also have the right to seize your bike anyway.
Personally I'm in favour of a gradual power increase but the law is the law.
arrrf.
