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Old 06-15-2008, 07:00 PM   #1
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Default Need TC set up help

As you can tell by my handle I am new to TC set up and I could really use some help.

First what are the pros and cons of balancing out my gearing with a larger pinion vs. a smaller spur?

I will start here and get into more ? later.
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Old 06-15-2008, 07:07 PM   #2
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The pros and cons of using a smaller spur vs a bigger pinion is mainly just getting it to mesh on your car. It does not change much performance wise (becides gearing of course). Just use the sizes you need that will mesh and give you your proper gearing.
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Old 06-15-2008, 07:07 PM   #3
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What type of car do you have?
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Old 06-15-2008, 09:55 PM   #4
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My son runs a Schumacher Mi2 and I run a Mi3. I am also looking into getting Pro 10 cars for both of us. But the immediate need is for the Schumacher cars.

As I see it changing the spur should effect the motor condition. I mean if I lower the spur and leave the pinion the same will I get the same motor temps? Is the motor seeing a different load overall? I am very curious as to why there are so many spur gears. They have to do more than just very the ratio., that can be done with pinions, cant it?
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Old 06-16-2008, 05:34 AM   #5
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Well for diffenrt motors there are diffenrt fanil drive ratios that you need to end up with . If you are running a BL motor and it is the 17.5 then most of the time it is hard to get the ratio you need with out going to a smaller spur
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Old 06-16-2008, 07:43 AM   #6
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A car has only certain amount of room to work with on the gearing. What Eflite was explaining was that if you run a 17.5 brushless you will need a small spur to gear it properly, at around 4:1 final drive ratio. If you were to run a 3.5 motor you would have to gear it at lets say 11:1 FDR. The only way to do these drastic changes is by changing the spur gear. Once you deside what motor you will run you start with the spur gear. Then you can fine tune your FDR with simply changing the pinion.

Remember that a brushless motor has way more torque than a brushed motor but less RPMs. A slower motor needs to be geared high to run fast. A fast motor needs small pinions to wind out.

Bottom line is you want your car to top out at around 3/4 down the straightaway for best results.
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Old 06-16-2008, 08:04 AM   #7
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Taking it to extremes, some may feel the larger spur,smaller pinion puts the weight of the motor more to the rear of the car, in turn giving a little more stability (and maybe a little more grip )but you would have to have a lot of racing experience to notice it.

For example, with a mid motor mounted car having the combo above may just help you a little more General rule of thumb though is you probably wont feel the difference.
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