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Radio Control Motorcycles Club of California R.C.M.C.C.

X-Rider BX4003 1/4 Dirt Bike
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The box looks like it came directly packaged from X-Rider and fit snugly inside the matching shipping box. Carefully cut cardboard shapes keep the bike centered and there is a separate bag for the instructions, spare axle, e-clips, and 6mm crash bars. The transmitter is in one of the included boxes and the lipo is already mounted inside the bike.

Body and Rider:
Body comes clear but already trimmed and mounted. The overspray film has come off in some areas so make sure those are covered before painting. The hollow molded rider has a light red (almost fluorescent) colorway. There are supposed to be holes on the bottoms of the feet to clip onto the foot pegs but only the right foot was done, so some foot hole reaming needed. The head looks down at an awkward angle, I wish it was tilted 5-10 degrees upwards.

The servo is premounted but looks very weak. It is very light so most likely plastic gears. I quickly replaced it with a Futaba metal gear high torque servo, luckily it had the same spline pattern.
The ESC is rated for 50A and connected to a sensorless 540 sized brushless motor. There is an ESC fan and another set of wires which are individually connected to each half of the metal swingarm which provide electrical connection to the rear e-gyro. This wire can be disconnected via JST plug. There is no speed control for the e-gyro, just fully on at all times. (+) and (-) terminals are set screwed onto both halves of the swingarm and electrical connection to the gyro is done via a very tight axle connection to both sides of the rear wheel. This means that no wires need to be routed into the rear wheel through the swingarm which is nice and clean.
Cube type lipo comes with the bike and has deans connectors preinstalled which is very convenient for me.
The transmitter is in a separate box and is plain jane in every regard, but has all the basic trims, reverse, and dual rate for both channels. There is a 3rd channel thumb switch but it has no use since nothing is plugged into the Rx 3rd channel. I ended up installing my own Rx and transmitter.

The chassis plates are black anodized aluminum and the updated versions with mounting provisions for a front brake servo and a slot so stick battery packs can be used in addition to the cube type.
The steering sadly is not the direct steering type but the Ricky type with two pivot points, luckily with ball bearings.
The front forks are spring damped only but very smooth. Springs are of the med-hard variety. (Note that the fork bottoms have "AR RACING" molded into them.) The rear shock is big bore with a fairly light spring, I was able to bottom out the rear tire on the chassis easily.
As for the wheels they run true but the double stick tape mounting the tire is not very strong, it feels like I can rip it off without much effort (but I didn't).
The larger 32P spur and pinion mean a very loud drive train but very robust. There is about 1mm of play in the spur drive shaft which can be easily eliminated with shims. The chain tension is on the tight side from the factory, I tried loosening the tension but added too much droop on one link of the chain to the point where it rubbed on the swingarm, so went back to stock tension which is probably correct to begin with.
The rear has a thin plastic molded tail fin as a wheelie bar which will most likely break off upon impact. I have since designed my own 3mm plates on shapeways which use the existing bolts to mount a rear airplane wheel.

Turning it on:
After turning it on I had to reverse my steering servo and recenter it, and lower dual rate to 65% to prevent going too far past the end stops. The ESC fan and e-gyro turns on immediately and takes 30 seconds to spin up to full power. It must have been centered well because I hear no friction in the rear wheel. On throttle the drivetrain is loud from the 32P gears but able to accelerate fairly quickly. On a 2S lipo I'm not expecting much but upgrading to a 3S might be too unwieldly for some throttle fingers.

Bottom line:
In the mid to high $300's price range it is a very good deal considering it is fully built up (fairly well, too), based on a proven chassis design, and you $100+ of electronics and lipo to run with (of which the ESC is highly specialized to handle the e-gyro, so not many places to buy something like this). The stock aluminum parts look good and there is always the opportunity of buying ARX option parts and installing them onto the bike since they are the same fit. First choices would be direct steering, front brake kit and a make it yourself steering damper.

The gyro is very powerful, picking up the bike to re-position it is a real chore because it is tough to rotate with your bare hands, which really shows how stable it is.

With the stock 3200mah 2S lipo it was able to wheelie with ease. The run time was at least 10-12 minutes, don't remember. On a flat speed run it was surprisingly fast.

1) Steering response is really slow. You cannot turn at full speed, you have to slow down significantly in order for the bike to turn. I did not try tightening up the steering springs but that would be the first thing to try. I do have the ARX direct steering upgrade ready to install so looking forward to that for comparison.
2) A steering damper would be nice, but not necessary. It still tracks straight even though little bits of grass and dirt shake the head a bit. Tightening up the steering springs would also help with this.
3) The rear suspension was very springy, seemed like the shock body needed thicker oil. Not too much thicker or else it wouldn't have been able to track straight on the bumpy grass. I have yet to disassemble mine to see what is actually in there.

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WEBMASTER: Ian Francisco ( - "grymg" on rcgroups, yahoo groups, yahoo messenger, etc... WEBMASTER: 2nd Kevin Hicks ( "Kev71H" on many forums: