I've got a 64cc ported polini kit on my free spirit. I'm running a phgb 20 through a 4 petal Reed. It's currently geared at 18/45. I'm trying to squeak out of the middle of the pack on the track. Should I change gearing?
What kind of track is it? Long straights, or lots of curves?
18x45 is good all around gearing, but being a polini you may be able to gear down slightly for more torque and just rev out more instead.
> Brandon Weiss (Detective brandon to you) Wrote:
> What kind of track is it? Long straights, or lots of curves?
> 18x45 is good all around gearing, but being a polini you may be able to
> gear down slightly for more torque and just rev out more instead.
Nope but it depends on pipe
18x45 is nothin it’s = to 16x40
I’d Run 16x36 to stay in to the mid upper range power
Believe it or not the max torque and hp on those kits around the low/mid 9000 RPM range I know because I run 4 of them
ReTune clutch to keep in power
It's a circuit track. It's called Grange motor circuit.
This is a great tool for figuring out what gearing you want for a certain speed or rpm.
With as technical as grange is, I'd gear down so that you're in your power more thru the turns and coming out of them. A few years back when I went to grange like the very fastest bikes were barely touching 60 at the end of the straight. With that treat pipe you're probably revving out to around 10 or 11k depending on porti g and other variables. I'd set it up so you're topping out low mid 50s, with the chance to hit upper 50s if ya got a buncha room to stretch out. I'd go with 16*45 or 15*45. Just depends what you want, quicker pull thru the mids or higher top speed.
On the track I've been gearing my polini at 13 or 14*45, but that's with a simonini pipe. Needs that short gearing to pull thru the lows without overheating the clutch, but it revs high enough that it still tops out in a good spot for the track. On the same bike on the street I have it at 16*45 and it's a super fun street blaster.
I also bet lowering your seat would help you feel more comfortable on the track. I'm a shitty racer but posture and being comfortable out there makes a world of difference
My thoughts exactly^^^
Thanks fellow brappers!
I believe i will drop to 16/45, and do a bit more fine tuning on my clutch (currently a braced two shoe). Also gonna buy a pull start to loose that starter clutch weight and nonsense.
The straight on grange is uphill, your gonna want 14x42-45 to be able to top out. I would also recommend a disc brake if you plan on actually racing.
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