BMI Racing "Copperhead 12" discussion and support
#1217
Tech Adept
I think using the carbonfiber sidelinks will help match up the front and rear better. With the 12RR car, there was a marked improvement when we all changed from the white fiberglass "hockeysticks" to the carbonfiber part instead. With that car (and the fiberglass sidelinks) it would loop pretty easy if the front and rear weren't coordinated well. I think the fiberglass piece has a more linear spring rate and the carbonfiber is a more progressive spring rate. The carbonfiber pieces on either car should make coordinating with the front setup a much wider target.
As I've gotten older I realize I have learned a lot of this stuff over the years, just have trouble remembering what it was sometimes.
#1218
The problem with running the pink rears is that up front for the first few minutes, it will feel ok but in reality, they grip a lot because they have allot of natural rubber in them and they push the front end through the corners. This is what gums up the fronts. As mentioned, Jaco orange, BSR gray/white or CRC graylow are the ticket.They are all equivalent to each other. They wont push the front on power. I have to say the pinks are about 90% of your problem. From there, you can reduce your camber gain by shimming the hinge pin block up 1mm. That should get you where you want to be.
#1219
It will work. My concern is that the mounting screws are so close together and only on one side of the motor. It looks as if the motor will have an easy time bending the pod in an impact from the leverage. I could be wrong but time will tell. Everyone has different ideas of how cars should be. If we didnt it would be a pretty boring class as we would all be running the same thing. Oh wait, that would make 1/12th just like TC. Oh please no!!
#1220
Heck, I'll take traction rolling right now over what it's doing!
I know it's as much me not driving the car as well as I know I could as it is car setup, I just need a LOT more rear traction throughout 8 minutes, or get rid of a lot of front grip. Once I can make 8 minutes on a relatively clean run, then I'll start looking to free the car up and get faster.
I think using the carbonfiber sidelinks will help match up the front and rear better. With the 12RR car, there was a marked improvement when we all changed from the white fiberglass "hockeysticks" to the carbonfiber part instead. With that car (and the fiberglass sidelinks) it would loop pretty easy if the front and rear weren't coordinated well. I think the fiberglass piece has a more linear spring rate and the carbonfiber is a more progressive spring rate. The carbonfiber pieces on either car should make coordinating with the front setup a much wider target.
Some of the online setup tips for 1/12 seem a little contradictory. On one of the same guides I read over, it says stiffening the rear generates more side bite and rear traction, and then goes on to say the general rule is stiffening the rear adds steering.
As I've gotten older I realize I have learned a lot of this stuff over the years, just have trouble remembering what it was sometimes.
Last edited by HarryLeach; 11-07-2010 at 06:11 PM.
#1221
The problem with running the pink rears is that up front for the first few minutes, it will feel ok but in reality, they grip a lot because they have allot of natural rubber in them and they push the front end through the corners. This is what gums up the fronts. As mentioned, Jaco orange, BSR gray/white or CRC graylow are the ticket.They are all equivalent to each other. They wont push the front on power. I have to say the pinks are about 90% of your problem. From there, you can reduce your camber gain by shimming the hinge pin block up 1mm. That should get you where you want to be.
#1223
I have the taller standoffs as well, but when I first tested with them, traction was too low to evaluate one way or the other.
I still think the 1.5 front links are too soft for our track, but I'll find out more this week.
I appreciate everyone's input, and I'll report back after testing later this week.
I still think the 1.5 front links are too soft for our track, but I'll find out more this week.
I appreciate everyone's input, and I'll report back after testing later this week.
#1225
#1226
time will tell, but the pod strength may be deceptive, as you know a short load path produces less moment, and its the moment that bends things. the rear pod height adjustment looks convenient for fine tuning, i would expect top to make different bearing holders for coarse adjustments, maybe a carpet and asphalt specific part set? the bearing holder looks to be engaged on 2 sides by the pod sideplate, so this may be better supported than it appears. also the cross tube should bear on the outer race support, and this tube diameter may also be deceptive, because of the additional bending rigidity. the tube wall thickness is probably driven by buckling, and bending rigidity is more than adequete.
note these are just observations, not a firm opinion for or against.
note these are just observations, not a firm opinion for or against.
I am going to be working on a new style of ride height adjustment. This style is not it. It is interesting and i take my hat off to them for trying it out.
#1228
Some of the online setup tips for 1/12 seem a little contradictory. On one of the same guides I read over, it says stiffening the rear generates more side bite and rear traction, and then goes on to say the general rule is stiffening the rear adds steering.
#1229
Not saying my cars are for everyone. Most all of the companies went for the low price tag and let you bring the price overboard in aftermarket parts. I decided to include it all and also go with quality instead of dropping all of the quality and boasting a low price tag. If you price out any of the other cars and then the upgrades needed to make it comparable, you are exceeding the price of our car. We didnt go to molded pods,standoffs,cheap C/F, and steel turnbuckles ect so we can drop the price. I went with making the best possible car i could and this costs more. For those who just want inexpensive, our car is not the one for you. There are cheap cars out there for those people. Just keep in mind,as with anything, you get what you pay for.