Ask Miles, our Setup AI that’s been trained on the SCX.
Setups
Gearing
Stock gearing for the XRAY SCX, with common pinions and their ratios.
| Pinion | Spur ÷ pinion | FDR |
|---|---|---|
| 15T | 5.20 | 13.78 |
| 16T | 4.88 | 12.92 |
| 17T | 4.59 | 12.16 |
| 18T | 4.33 | 11.48 |
| 19T | 4.11 | 10.88 |
| 20T | 3.90 | 10.33 |
| 21T | 3.71 | 9.84 |
| 22T | 3.55 | 9.40 |
| 23T | 3.39 | 8.99 |
| 24T | 3.25 | 8.61 |
| 25T | 3.12 | 8.27 |
| 26T | 3.00 | 7.95 |
| 27T | 2.89 | 7.66 |
| 28T | 2.79 | 7.38 |
| 29T | 2.69 | 7.13 |
| 30T | 2.60 | 6.89 |
Shaded rows are the pinions most 1/10 2WD short course truck setups run on the stock spur.
What pinion should I run?
Tell us your motor and track and get a starting pinion for the XRAY SCX, with the range racers in the class run.
Get a recommendation →Shop pinion gears at AMain →What pinion gear should I use on the XRAY SCX?
It depends on your motor and the track. In the 1/10 2WD short course truck class, racers gear by final drive ratio: 7.5–8.5T near 10.14, 13.5T near 8.94. On the SCX's stock 78T spur that is about 20T for 7.5–8.5T, 23T for 13.5T. Tight tracks gear down, open tracks gear up. For a starting pinion matched to your motor, use the So Dialed Pinion Recommender with the SCX selected.
What is the internal ratio (transmission ratio) of the XRAY SCX?
The SCX has an internal ratio of 2.65:1. Final drive ratio = spur ÷ pinion × 2.65. With the stock 78T spur, a 15T pinion gives an FDR of 13.78 and a 30T gives 6.89.
How many teeth is the stock spur gear on the XRAY SCX?
78 teeth. Changing the spur moves every pinion's ratio at once; most racers leave the spur and tune with the pinion.
Kit setup
Kit shock setup. Part numbers link to AMain.
- Front
- 650 cst
- Rear
- 500 cst
What shock oil does the XRAY SCX come with?
Out of the box the SCX runs 650 cst front, 500 cst rear (XRAY oil), on 2 x 1.6mm (#368031) front, 2 x 1.7mm (#368031) rear pistons. That is the kit setup; you will need to adjust it for your track conditions. The RC Setup App can help dial it in.
What springs does the XRAY SCX come with?
The kit springs are 45mm Linear 4 dot (#368186) front, 60mm Linear 3 dot (#368286) rear. Stiffer springs suit high grip and big jumps; softer springs add grip on slick or bumpy tracks.
Setup Help
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Setup App & Race Log
Your XRAY SCX is in the RC Setup App
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