Does this mean i cant race?

[HPI_freak]

i am thinking a bout racing in the HPI Challenge in Ohio, depending on where its gonna be at. anyway, i was looking in the rules for the Micro Pro class and i found this:

BATTERIES
- Any 2/3AA (the type provided in HPI option Micro battery packs) or standard AA or AAA batteries are allowed, a maximum of SIX batteries may be used
- Batteries must be alkaline, nickel-cadmium or nickel-metal hydride
- Batteries may be mounted as desired

does this mean i cant use this?:

[SteveK]

I looked it up on Tower, and that should be OK: 6 cells/7.2 volts, NiMH, right size.

What makes you think it wouldn't be legal?

[TimisTim]

If you really want to you could use AA alkalines which produce 1.5v per cell. Which would be 9v versus your NIMH's 7.2v. Im not sure on the runtime or power output of these cells, but they have 2000+mAh cells out there (Im not sure if they are alkaline). But this is just something I thought up spur of the moment. It may be good to look into it.

[SteveK]

Only alkalines put out 1.5 volts per cell, and they actually have less power because of their higher internal resistance. 6 NiMH or NiCad cells are 7.2 volts. Plus you lose out because of the added weight of the full AA cell.

[Grizzbob]

Quite right, I race my micro locally in a kind of stock class we came up with(we run stock motors like Orion's, Elite Stock, HPI's kit motor or XRay's stock motor & 6 cell packs), & some of my friends hav tried using alkaline AA's instead of a 6 cell rechargable pack, & their cars were always slow with the AA's compared to the rechargable 6 cell packs, because of the weight & lower resistance of the rechargables. And about capacity, even with mild mod motors, a 110-1200mah pack will have all the capacity you'll ever need for racing(we used to do 10 minute mains in our stock micro class, & most times, we could finish it & keep running another 5 minutes or more afterwards, quite fun).... :cool:

[HPI_freak]

yes, this battery pack was the first thing i bought for my micro and i could tell, it was WAY faster with rechargeables versus alkiline batteries with my stock motor. when i bought the HPI mod motor, the power only went up slightly. i thing the batteries made it go faster than the new motor.

[SteveK]

Yeah, there was a speed comparison in a magazine with the Mini-T, with alkalines, an aftermarket pack, and stock and modified motors. The batteries meant about a 50% speed increase, the modified motor only meant about a 10% increase. I think it was like 10mph up to 15mph with the stock motor, and 12 to 17 with the modified.