The Best Track has a more abrupt transition than the feedom. Do you alter your COG depending on the track?
Is a .5 to .625 COG to aggressive for the Best Track?
COG - Best Track VS Freedom
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Ickabod Crane
- Journeyman
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- Joined: Mon Jan 28, 2013 9:24 am
- Location: Bloomer, Wisconsin
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Shawn Stebleton
- Master Pine Head
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- Location: Monroeville, PA
Re: COG - Best Track VS Freedom
If the COG is too small (under 1/2" or so) and the weights too spread out longitudinally (front-to-back), you will pop a wheelie on the Best Track during the transition. The likelihood is greater on the old sharp curve and less on the newer not-so-sharp curve. I've seen that happen at our district races. I didn't know exactly what the COG's were of the various cars that did pop one, but it looked like they were extremely rear-weighted. The weights need to be very concentrated longitudinally for an aggressive COM.
The Freedom track is similar in shape to our pack's Piantedosi Classic (wood) track and I've never heard of COM issues with it. It has a gentle curve. You'd run into alignment difficulties long before popping wheelies due to the curve.
My son has a 1/2" COG on his current car and will race tomorrow at districts. We don't know definitively that it will be another Best Track, so I can't say for certain that I can give results on one, but last year he also had a 1/2" COG and didn't pop a wheelie on the old-style sharp curve Best Track. However, please note that about 4.03oz of tungsten plus about 0.1oz of lead tape were within a space of less than 1" longitudinally. Since it was right around the rear axle, add in the weight of the two wheels and axles, plus a machine screw to hold things together, and I think over 4.5oz is within a 1" longitudinal area right around the rear axle. Now that is concentrated!
For the Best Track, I would also cant the DFW down (and forward for railrider) so the wheel rides on the inside edge of the rail instead of scuffing along it. When the car is going onto another section at a transition, if the rail of the section the car is going onto just a little out of alignment (i.e. sticking out) the car can easily pop a wheelie or get pushed outward quickly. You will hear the plastic hit the aluminum clearly. It's not a good sound to hear. If the wheel can roll on the edge at a slight angle, it will likely just roll over the bad joint.
The Freedom track is similar in shape to our pack's Piantedosi Classic (wood) track and I've never heard of COM issues with it. It has a gentle curve. You'd run into alignment difficulties long before popping wheelies due to the curve.
My son has a 1/2" COG on his current car and will race tomorrow at districts. We don't know definitively that it will be another Best Track, so I can't say for certain that I can give results on one, but last year he also had a 1/2" COG and didn't pop a wheelie on the old-style sharp curve Best Track. However, please note that about 4.03oz of tungsten plus about 0.1oz of lead tape were within a space of less than 1" longitudinally. Since it was right around the rear axle, add in the weight of the two wheels and axles, plus a machine screw to hold things together, and I think over 4.5oz is within a 1" longitudinal area right around the rear axle. Now that is concentrated!
For the Best Track, I would also cant the DFW down (and forward for railrider) so the wheel rides on the inside edge of the rail instead of scuffing along it. When the car is going onto another section at a transition, if the rail of the section the car is going onto just a little out of alignment (i.e. sticking out) the car can easily pop a wheelie or get pushed outward quickly. You will hear the plastic hit the aluminum clearly. It's not a good sound to hear. If the wheel can roll on the edge at a slight angle, it will likely just roll over the bad joint.
Shawn
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Ickabod Crane
- Journeyman
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- Joined: Mon Jan 28, 2013 9:24 am
- Location: Bloomer, Wisconsin
Re: COG - Best Track VS Freedom
Beautiful! I'll be sure to cant the DFW down on our cars. There were issues with the sections of the track not lining up. I did see several cars pop wheelies last year, including ours. Last year we did not build RR cars. This year, all will be.
