SirSpeedy
05-01-2001, 01:02 AM
Someone asked me to help them with some tweak/weight distribution info. This is from my friend Adrian Martinez of Team Shumacher. Hopefully you can use it.
"....Tweaking your car means getting the left to right weight distribution equal on each end of your car. There are a few things you need to do to your car before you tweak it:
1. Remove your wheels and shocks and place the car on a smooth FLAT surface. Use your grub screws to set the a-arms heights. I use a ride height gauge to set the tips of each a-arm 3mm (for my base setup) from the flat surface the chassis is resting against.
2. All Schumacher Sedan have a pivot ball that threads into the bottom of the hub carrier. If all four pivot balls aren't screwed into the hubs to the exact same depth your car will seem tweaked. After you have set the a-arm heights. Use a ruler or the depth measuring part of a set of calipers (the part that sticks out of the bottom of the caliper as you open it) to measure the height of the L and R front axles. Thread the pivot balls in our out until they are the same. Then do the same to the rear. Front and rear axle heights don't have to match up. If you use different a-arm height settings they won't and that OK.
Once you have done the preceding steps your car should be mechanically tweak free and any tweak should be due to electronics choice and placement. An LRP Quantum is lighter than a Novak Cyclone and my favorite servo (Airtronics 737) is tons lighter than Paul Wynn's favorite metal gear, high speed stump puller (Airtronics 257).
Put the wheels back on the car. If you have stock shocks put them back on. If you have Threaded shocks you have to equalize them. To do this tighten the threaded collar of the shock down until it stops then use a permanent marker to put an index mark on the top of the collar in the same place on all you shocks. Now loosen all of you threaded collars the same number of turns (10 turns is a good starting point). Put you shocks back on the car. Set your ride height being carful to turn the L and R collars on the front and L and R collars on the rear the same # of turns. Note that you will have to have a different # of turn front to rear to achieve the correct ride height, that's OK, just make sure each end of the car is = L to R. Now you can check the tweak of your car.
One of the cheapest and best ways I've found to do this is with an MIP tweak station. When you car is ready to run with motor, electronics and batts in place put your car on the tweak station and adjust preload on your shocks until the bubble level on the balance beam is right in the center. I try to spread adjustment across all 4 corners of the car. If I need 1/2 turn of a threaded shock more preload on my left front wheel to make my car flat I will give it 1/4 turn and do the same to the right rear thus balancing the car. Its a good idea to recheck ride height now.
I find that if there is a difference in ride height L to R then most of the time the axle heights are not =. Sometimes the left front part of the chassis is ~.25mm lower than the other corners of the car. This is usually due to the weight of a monster metal gear servo. However, as long as the car is level on the Tweak station this will have no effect on how that car handles on the track.
FYI, generally we at Schumacher USA don't get this crazy into setting a car up unless we are at a National/Large race. For club racing and most state series races we just check camber, ride height, toe , a super quick check on the tweak station then just run it. Remember, this is supposed to be fun!"
See ya...
"....Tweaking your car means getting the left to right weight distribution equal on each end of your car. There are a few things you need to do to your car before you tweak it:
1. Remove your wheels and shocks and place the car on a smooth FLAT surface. Use your grub screws to set the a-arms heights. I use a ride height gauge to set the tips of each a-arm 3mm (for my base setup) from the flat surface the chassis is resting against.
2. All Schumacher Sedan have a pivot ball that threads into the bottom of the hub carrier. If all four pivot balls aren't screwed into the hubs to the exact same depth your car will seem tweaked. After you have set the a-arm heights. Use a ruler or the depth measuring part of a set of calipers (the part that sticks out of the bottom of the caliper as you open it) to measure the height of the L and R front axles. Thread the pivot balls in our out until they are the same. Then do the same to the rear. Front and rear axle heights don't have to match up. If you use different a-arm height settings they won't and that OK.
Once you have done the preceding steps your car should be mechanically tweak free and any tweak should be due to electronics choice and placement. An LRP Quantum is lighter than a Novak Cyclone and my favorite servo (Airtronics 737) is tons lighter than Paul Wynn's favorite metal gear, high speed stump puller (Airtronics 257).
Put the wheels back on the car. If you have stock shocks put them back on. If you have Threaded shocks you have to equalize them. To do this tighten the threaded collar of the shock down until it stops then use a permanent marker to put an index mark on the top of the collar in the same place on all you shocks. Now loosen all of you threaded collars the same number of turns (10 turns is a good starting point). Put you shocks back on the car. Set your ride height being carful to turn the L and R collars on the front and L and R collars on the rear the same # of turns. Note that you will have to have a different # of turn front to rear to achieve the correct ride height, that's OK, just make sure each end of the car is = L to R. Now you can check the tweak of your car.
One of the cheapest and best ways I've found to do this is with an MIP tweak station. When you car is ready to run with motor, electronics and batts in place put your car on the tweak station and adjust preload on your shocks until the bubble level on the balance beam is right in the center. I try to spread adjustment across all 4 corners of the car. If I need 1/2 turn of a threaded shock more preload on my left front wheel to make my car flat I will give it 1/4 turn and do the same to the right rear thus balancing the car. Its a good idea to recheck ride height now.
I find that if there is a difference in ride height L to R then most of the time the axle heights are not =. Sometimes the left front part of the chassis is ~.25mm lower than the other corners of the car. This is usually due to the weight of a monster metal gear servo. However, as long as the car is level on the Tweak station this will have no effect on how that car handles on the track.
FYI, generally we at Schumacher USA don't get this crazy into setting a car up unless we are at a National/Large race. For club racing and most state series races we just check camber, ride height, toe , a super quick check on the tweak station then just run it. Remember, this is supposed to be fun!"
See ya...