Pocket bike idles, but doesn't rev under load

[racefactory]

21 mm is overkill for these bikes you will lose all your bottom end.

19mm is what the mass say is the best carb for B1 water cooled, 17 and 18 and nice too bit more bottom end. i run a banshee carb which is 17.5mm

[Gadgit]

I know of one GP3 running a 21mm He shows up to Mt Welly track now and then and dominats... It's still all in set up and what you want the bike to do... throw a 19mm on a std day2 and I don't think it will preform any better... I do also recall the hillbillies running a 22mm carb on Kens Day1 mod and it was a real screamer but there was alot of custom bits in there to.. Still comes to what the engine flows like and ya riding style.. some like it easy some like it with a bit of restriction lol

[racefactory]

yeah that is true nice post

[orange]

just because it's running it doesn't mean it's running at it's best.

[Junkers]

Well.. back to the topic. Got my new engine and it goes, unbelievably I struck more problems but solved them with a little time ( fuel filter started to leak etc). Happy as larry now. Although.. that new dellorto style carb seems to be misbehaving, but I'm going to leave it alone.

Fixed my friends one at the same time, his is identical except he has a "race" clutch (has grey clutch material instead of brown). His seems to pull much harder than mine. Are they really that much better or could it be something else?

[daytona 2]

if you want real clutch push get a BZM

[BigAl]

Are they really that much better or could it be something else?

More likely the difference in performance is the clutch setup. Try measuring his spring length and applying it to yours.