2 stroke question

[willy_01]

Hey just a quick question. I own a RG250 which is two stroke, I have read on the specks sheet that there compression is a mear 7.4:1 standard. Anyway my question is, is there a difference between 4 and 2 stroke compression ratio's because 7.4:1 on a car is insanely low, and therefore extremely inefficient (bar the exception of running huge amounts of boost I guess). Basically I’m wondering if I can shave the head and up the compression cause I’m fully over the whopping 45hp this bad boy puts out standard.

[stanko]

Yes there are 2 kinds of way to measure compression. The normal way is to take the capacity of the bore x stroke etc and express it as a ratio over the combustion chamber volume at TDC. The other way is the corrected method which is for 2 strokes you dont start measuring the cylinder volume till after the exhaust port closes (until then there is no compression) so the value you get is going to be lower than a 4 stroke of similar bore stroke. If you need more power buy a different bike.

[willy_01]

cheers for that mate, I thought that there must be something to it like that, right, now i just need to sell my bike haha.
This 250cc max licence thingy really kills biking for a big fella like me, sure my bike would probally go well with a little person on it but i aint little.
Sorry about that wine, another question tho. What about pod filters, will this really help by being added to the standard set up or without re-jetting would i hit flat spots (in rev range) and in effect run a far higher risk of blowing the dam thing up?

[curious george]

Pod filters are a pain in the arse, and don't work as well as a well thought out airbox.
Better with a new bike for more power.
best thing for power is better pipes and a dyno run, nothing else really makes as easy HP.