REPAIRS & MAINTENANCE
Kart Bearings
Rear axle bearings should be inspected after every run. Spin axle and listen for any grinding noise or clicking.
Bearings should be replaced if they are noisy.
For bearings that exhibit no noise problems, remove the seal/shield and add a good quality bearing lubricant. Replace seal/shield and run.
A good trick to use is to polish the surface of the axle that runs in the bearing race. Remember the chassis flexes and anything that helps the frame flex is good. Trust us, do this to your axle.
Spindle bearings should be checked very frequently. If the spindle exhibits any slack, you probably have a bad bearing. Always use bearings that have metal retainers, don't forget to put in the spacer when replacing bearings.
Cleaning Your Kart
To clean your kart you should have a lot of rags, Brake Cleaner, WD-40, Simple Green, and a Silicone Cleaner.
First you should take off your side pods and tires. Next start at one end of the kart and spray with a light coat of WD-40 to loosen grease and rubber. Wipe off completely. Make sure not to spray brakes or rotors with WD-40 In heavy grease build up areas repeat process as necessary.
After this you should clean your brakes wit Brake Cleaner don't be afraid of soaking brake pads because Brake Cleaner dries leaving no residue.
Next use simple green to clean side pods and driver fairings. For rubber marks use Brake Cleaner, but make sure not to get it on your stickers! Also to clean off rubber marks use razor blade or Scotch-Brite pads.
After you have cleaned everything spray silicone cleaner on a rag and wipe over everything but brakes, this will make everything shiny and create a surface that will be easier to clean next time.
Cooling System
Make sure all hoses are free of kinks, are properly attached and are not rubbing on the ground or on some part of the kart.
Fill the system with water that has been treated with Water Wetter or some other brand of water coolant treatment.
Make sure you purge the system of any air pockets. Do this by lifting the radiator side of the kart above the highest point of the engine.
Start engine, remove radiator cap and make sure water is circulating.
Silencer Care
Always make sure our silencer is not crushed or has leaks. It is
common for silencers to have their rivets beat out. You should re-rivet them as needed.It is also necessary to repack your silencer with new packing. To do this you might have to drill out the rivets and then buy new packing at your local motorcycle or kart shop.
When you repack the silencer make sure to wrap it very tightly. Try and get as much packing as possible in the silencer.
Drive System
Sprockets should be checked regularly for undue wear. Pointed teeth or stretched chains are signs of a bad sprocket.
Make sure that sprockets are properly aligned and tightened.
When changing ratios or moving engine make sure when the engine mount is retightened that the chain has a minimum of 1/2" of slack at the midway point between the sprockets.
Oil or lube the chain with a high-quality chain lubricant. The Trackmagic Racing Team recommends Torco Power Slide Titanium Series chain lube.
Lube the chain before every run.
Exhaust System
Take care of your tuned expansion chamber. Because expansion
chambers are tuned with their shape and size it is critical not to dent or bend them in any way. Also, it is crucial to prevent exhaust leaks.Make sure your expansion chamber fits snugly on the exhaust header and has strong springs. If you can pull the expansion chamber off the header with the springs on it, then you need stronger springs.
Make sure your silencer fits snugly as well.
After each race you should spray your pipe with WD-40 and keep in a dry warm place to prevent rusting.
Gearbox Oil
Use a high quality motorcycle transmission oil.
The Trackmagic Racing Team uses and recommends Torco MTF.
The recommended amount is 525cc for a Honda CR 125cc and CR 80cc.
Check with product manufacturer for other engine types and sizes.
Oil should be changed frequently, we recommend a change every half hour of running
Wheels
Inspect your wheels when you mount new tires. Be very vigilant of cracks or dents. Discard rims if they are damaged due to impact with curb or crash.
Do not use soapy solutions when mounting tires. Use proper tire
mounting lubes, this will prevent moisture build up in your tire and
prevent tire slip on your rim.Mount rims to hubs carefully. Do not tighten unevenly. Use nuts
that are in good condition. Final torque setting for wheel nuts is 24
foot lbs.
Breaking-In New Tires
Tires have a slick surface on them when they are new. This surface is a seal to keep the oils and other ingredients in the rubber fresh. A coating of mold release is also on the outer surface of the tire and
this, as you might imagine, is also very slick. Because of this the first few turns on your new tires will be very slick. Try not to slide the kart much the first lap or so. This may sound backwards, but every heat
cycle on your tires makes them harder, so you want to bring them up to temperature slowly the first time so that your tires will be at their best for the race.It is also necessary to repack your silencer with new packing. To do this you might have to drill out the rivets and then buy new packing at your local motorcycle or kart shop.
When you repack the silencer make sure to wrap it very tightly. Try and get as much packing as possible in the silencer.
Setting Your Tire Pressures
Once you have scrubbed your tires and brought them up to temperature, pull into the hot pits and check your tire pressures HOT.
Set the pressures to your desired setting when they are hot. We set the tire pressure hot because this is where the tires operate on the track. (Cold pressures are only a starting point).
When the tires cool, take note of the pressure, this will be a good starting point next trip to this same track.
Different tracks will work the tires differently so the hot pressure you will set to your optimum, but you will see a big difference in the cold pressures.
Tires - Qualify & Race
When its time to qualify put a little extra pressure in your tires, this will build heat quicker creating more grip for the short qualifying session. Don't try to race with these pressures or your tires will overheat and slow down.
You should know your race pressure from practice, the pressure that lets you run at your optimum for enough laps to last the race. (Too high and your tires will slow down after several laps. Too low and your tires won't have enough grip in the beginning of the race).
Run mock races in practice to find this pressure and make sure you check it hot.
Check the pressures when the tires have cooled down and make a note of both hot and cold pressures in your log.
Tires - Off the Track
Tire care off the track is important and very often overlooked. Once you have run your tires you break the outer seal that we talked about earlier. This seal was to keep the ingredients in the tire fresh and therefore at their optimum. Now there is nothing to protect your tires against getting stale.
Wrap your tires in a plastic wrap like Saran Wrap and put them in a dark bag like a Trackmagic tire bag. This will keep the atmosphere and light from drying and hardening the rubber on your tire. This is especially true in regions that race on hard compound tires that can be raced on more than once, but even one race compounds can be used for practice if you store them properly.
Tires have the biggest effect on handling and lap times and can also be the biggest expense to go racing.
Keeping this in mind you should learn how to use them to their fullest. If you can do this, you should be in the hunt at every race.