• Make sure you rotate the front and rear pair from side-to-side after one or at the most two runs on the track. This will allow them to wear evenly
throughout their life as most tracks cause one side to wear more than the other. Uneven wear is common since most tracks have either a high
speed sweeper or more turns in one direction.
• Use a micrometer to measure the diameter of your tires before and after each run. Taking measurements will help you to make sure that any
handling problems are not caused by unequal tire diameters. Taking measurements of the inside and outside edges of each tire after a run will
also help you to diagnose setup problems, such as improper or unequal camber or camber rise settings.
• Mark each tire with its original position (LF, RF, LR & RR) on the car with a permanent marker. Include its compound if there is more than one
compound being used at any given time and they are not already marked. This will help you to keep track of what is happening with each tire
concerning the tips below and also minimize mounting the wrong compound on the front or rear.
FOaM TIRES - TRUING/SIZING TIPS
• Use the #1000 HUDY Tire Truer to trim all new sets of four tires down to 0mm to start with, and use them for practice only (if possible) until
the smallest one of the set reaches 8mm.
• Then lightly skim the other three tires down with the tire truer until they are all exactly 8mm and use them for qualifiers until the smallest one
reaches mm.
• Then even them out again with the truer and use them for main races only, until they reach the legal minimum diameter as stated by the rules at
the race. If there is not a minimum diameter rule, usually anything under mm at the start of a race is not recommended.
NOTE:
If your setup causes your rear tires to wear faster than the front tires, then add .mm to .mm of diameter to the rear tires when truing them down.
This will make sure that they do not wear down to a smaller diameter during a race and cause the rear end to abruptly lose traction. Maintaining
even diameters on all four tires throughout an entire run is the goal. However, larger rear tires are always better than smaller ones.
FOaM TIRES - TIPS FOR PREvENTING cHUNKING
• Aside from hitting things, your tires will chunk more often if there is not enough negative camber in the middle of the turns at full chassis roll to
keep them from riding on their outer edges. This happens more often on the rear tires than on the front.
• Check the diameters of the inner and outer edges of each tire after each run. Pay particular attention to the side of the car that wears the
tires down the fastest as this side will shoulder the greatest amount of cornering forces for any given track. Treat both front and rear tire pairs
separately, even if they are the same compound. If either tires outer edges within a front or rear pair have a smaller diameter than their inner
edges, then increase the static camber in 0.° increments, rotate the tires from left to right and track test them again. Keep increasing the static
camber until the tires wear evenly flat on the front, and one or both of the rear tires wear just a little bit more on their inside edges (no more than
0.1mm after two or more runs). If you follow these steps and reach -.0° camber on a set and one or both of them are still wearing the outside
edge, then you need to increase the amount of negative camber rise on the outside wheel as the suspension compresses during cornering. This
is accomplished through shortening the camber links by moving the inner pivot point to an outer position using the XRAY Quick Roll Centers™
adjustment. If you are already using the outer holes, then you can use shims between the outer pivot ball joints and the hubs to raise them up
so that the camber link rods slant downward from the outside in towards the center of the car. Slanting the camber links also increases negative
camber rise. However, increasing the slant angle of the camber links will raise the roll center at that end of the car as well.
• Place a semi-thick coat of CA glue on the entire outer sidewall of the tire, from the edge of the rim to the top of the sidewall and let it dry
sufficiently (0-0 minutes). You can speed up the drying process by wrapping the outer/bottom surface of the tire with a paper towel, and
spraying instant cure onto the wet CA glue. Wrapping the surface keeps the instant cure spray off the tires contact patch and possibly minimizing
grip. Mount the tire on a tire truer and use a file or sandpaper to round off the inner and outer edges of each tire and remove approximately
1mm of the CA glue from the top edge of the outer sidewall. This will allow the outer sidewall of the tire to flex some while cornering and keep
the CA from cracking. You will need to round off the edges every two to three runs as well.
FOAM TIRES & BEARINGS
FOaM TIRES - GENERaL TIPS
BEaRING MaINTENaNcE
The following procedures are recommended to clean all of the bearings in your T. For high-competition racing, we recommended doing this every
- weeks, or before a major race.
1. Remove the blue seals on both sides of the bearing by inserting the tip of a hobby knife into the inner seam and prying the seal up and out.
. If the seal bends a little and you can see a kink, carefully flatten the kink out by hand.
. Spray the seals with motor cleaner and blow dry with compressed air.
. Spray the bearing on both sides with motor cleaner.
. Spin the bearing while it is still wet to dislodge any particles with the cleaner.
. Spray the bearing on both sides again.
7. Blow both sides of the bearing dry with compressed air to make sure particles come out.
8. Hold the inner part of the bearing with my left thumb/forefinger and spin it to make sure it spins free without any abnormal vibrations or sounds.
. Place one drop of bearing oil into each side of the bearing.
10. Replace both seals at the same time by lining them up on each side of the bearing and lightly pressing them in all the way around the bearings
circumference with your thumb and forefinger. Do not press too hard or use any type of tool, such as a wrench tip, to push the blue seals in as
they will push in too far, bend and cause drag.
If you spin test the bearing after you have re-oiled and sealed it, it will not spin freely for an extended period of time. The lightest of oils may allow
it to spin for 1- seconds. This is normal and once you have mounted the bearings in the car again, the drive train will spin freely.
Make sure you use a motor cleaner that does not leave a residue after it dries as this may cause drag and wear in the bearings.
