gearing`

[rumblebee147]

im running a orion 12 double nd am looking for alittle different gearing. its fast but id like to change it up alittle bit and maybe give it alittle more bottom end .. im running a 20 pinion .. what do you think i could put in it to make it do that

[dalejrfan8]

It would help if you mentioned the car that you are driving, but if you want more acceleration just drop your pinion one or two teeth.

[rumblebee147]

im running a rc 10 t4

[highroller]

If you are looking to change the way it accelerates there are several things than can be done. First mark the position of can using a permanate marker, mark one endbell retaining screw and put a corresponding mark on the motor can to help orienate it back to correct timing position or invest in a motor timing guage.
1. Gearing - find the pinion size that works best for the track layout you may need to purchase an assortment 16 to 21 or 17-25 depending on spur gear. Try altering the pinion in one tooth ranges to see which gets the best results - good acceleration, speed and runtime.
2. Spur- generally the stock spur works fine for stock racing and bashing, but with actual racing changing it to a large 87-90 with modified motors allows the motor to reach it's power better. So just switching to a bigger spur but using the same numeric gear ratio may help some.
3. Timing advancing the timing increases the rpm ranges motor makes - to a point this increases the acceleration - but to see any noticeable difference you may need to drop a tooth or two on the pinion. Or you can retard timing if acceleration is too much (powerful) for track conditions and increase the pinion by one tooth to maintain some speed and still maintain runtime.

First try to find the numeric gear ratio (quoted as final drive ratio) that works best then use the other methods to achieve the final results. If you switch to different turns like a 10 turn again compensate by gearing 1-2 teeth lower than you did with the 12 turn, and hgher in turns gear up. Associated has a list of gearing suggestions for vehicles and motors found through the tuning guide link. Or look for information and postings for the T4.