I’ve noticed a lot of newer members having problems with speed or asking questions about their cars, so here’s my tutorial on how to clean, lube and weight them. This guide is very basic, with things that a lot of the experienced members probably already know about, but most of the newer members don’t.
I’ll break this up in a few sections,
1) Separate the good cars from the bad
2) Cleaning
a) Taking apart
Leaving them together3) Lubing
4) Weighting
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1) Separate the Good Cars from the Bad
Just about everyone here buys their sets from Ebay, where the cars in the sets have been run before, at sometimes more than one house. Now you have these cars, which have probably built up a lot of stuff in the wheels. Some cars are newer and run better than others, so here’s how to get the best cars in your train.
There are two ways to test which cars are best for your train; the first is spinning the wheels individually with your fingers, and seeing which cars have the wheels that spin the longest. Make sure you spin the wheels at the same speed, or the results could be wrong. The other option will only work if you have something built, or are willing to build a test hill. Always use the same front car if you are testing middle/back cars, and always use the same back car if you test the front cars. Drop the train, and mark where each train with a different test car makes it. Obviously, the train that makes it the highest has the best cars, which are the ones you want in your train. Do this until you have narrowed down enough cars for your train. Try to get atleast 4 to 5 good cars in the train, too many or too few cars lose speed fast. If you need more cars, call or email Knex.com and they will sell you them.
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2) Cleaning
Without clean cars, lubing and weighting will do very little to help. Most likely, your cars axles are covered in built up dust and other things that could get on them through shipping. There are two ways to get this off, one is taking the cars completely apart and wiping the axles, and the other is using a toothpick to try to get it off.
2) (Part 1) Taking the Cars Apart
I’ve never taken my cars completely apart, and they run perfectly, but I have taken them this far apart.
Start off by unscrewing the orange top of the cars from the wheel part. Once you get it off, the running wheels will come off. That’s as far as I’m going to take them apart, but you probably could get the wheels fully apart if you unscrewed all of the screws.
Next you want to wipe off the axles of however many wheels you took out of your cars, and clean out the part where the axles go. If you’ve never done this before, there should be a lot in there. Rinse the black wheel base out in a sink, put the running wheels back in, and screw it back to the cars. Do not lube your cars yet; it will just make them worse.
2) (Part 2) Cleaning Without taking Apart
This can be done much easier and faster than taking them apart, and works almost just as well. First, get a few toothpicks and start pulling at anything wrapped around the wheel’s axles. Depending on if you’ve done this before, and how long you’ve had the cars, there might be a lot, or nothing on the axles. Rinse the wheels out in a sink to get anything that fell into the wheels out, and let them dry. Using soap can also help, but make sure it’s rinsed out well.
Some cars might have more or less than others, but inside the red box is what you want to get out.
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3) Lubing
Do not lube your cars until you have something built to run the cars on. Once the cars are lubed they must be thrown through the track several times to break it in. Also, do not lube the track, it will cause the wheels to slip and lose speed.
Lubing your cars is very important to keeping speed. I use a silicone-based spray, which can be found for only a few dollars at probably any hobby store. Spray every wheel of every car on your train and wipe them down a little to get the lube off the outside of the wheels. Then, try not to let your cars sit for more than a few minutes before taking them to a pre built track. Throw them through the track several times to break the lube it. You should notice an improvement in the cars after a few runs. The cars will get lube on the rails, which can slow your cars down, so wipe this off if you notice a lot. If you don't notice improvement in the cars, add a little more lube, or wash it out and try it again. If everything was done right, it should work.
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4) Weighting
Weighting your cars can most of the time double your speed, unless the supports can’t take it. Weights will cause more force on the supports, and if they aren’t strong enough, will cause movement in the track, killing your speed.
The weights I use on my cars are 4 stacks of 4 pennies, with a stack of 5 in the middle. More weights will cause more work for the motor, so be careful weighting your cars if you don’t have enough motors for the lift.
The stack of 5 in the middle was super glued to the 4 bottom stacks, but it can be taped if you don't have any.
Make sure the weights are tightly taped to the cars, or the weights will be able to move, killing speed.
For the front car, spread the stacks of weights out more, and cut a hole in the tape, so the chain dog can move.
I think I covered everything that's needed, but I can add things to the tutorial if there are any questions.
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