Kyosho Raider Restoration (part 2)

Reassembling the Kyosho Raider using the instruction manual was an easy task.  The kit was designed for beginners, so the assembly steps were not complicated at all.  As usual, I replaced all of the bushings with ball bearings.  I used a Futaba R113ip receiver with Novak 3 Amp BEC (#5460), Tamiya TEU-104BK electronic speed control with original Kyosho Le Mans Stock 05 motor and a Futaba S148 servo for steering.

The wheels and tires in these pictures are old Kyosho/Duratrax street tread because I wanted to drive the chassis around for a bit in order to test it out.  I didn't want to use the original wheels and tires because they were still disassembled while I decided how to whiten the wheels which have yellowed with age and UV exposure. 

It's interesting that the battery tray molded into the main chassis is offset to the right in order to compensate for the weight of the motor hanging off the left side. 

The shocks are friction type, not oil filled, which is typical of beginner-class vehicles. 

The steering geometry in the Raider has some quite severe bump steer traits which is also typical of less expensive beginner class vehicles.  Lifting the front end causes very severe toe-in of the front wheels.  In the shot below, the front suspension arms are just above level.  This height is close to where the front end settles during normal driving so I tried to adjust the steering tie rods so toe-in is minimal at this position.  Having some toe-in is normal and desirable in most off road buggies.  Continuing to push down on the front end results in some toe-out, so it is a delicate operation to try to find the right length for the tie rods that allows the front end to perform steering duty without wearing out the tires too quickly or causing strange steering behavior while driving.

The raised mounting position of the steering servo is also very interesting.  This position raises the center of gravity of the vehicle - generally not a good thing in an off-road buggy where stability is important.  

The Le Mans Stock 05 motor cleaned up very well with some motor spray.  The brushes are still in good shape.

The access panel on the side of the gearbox (just behind the antenna tube in the below picture) is for gaining access to the motor mounting screws, inspecting and greasing the pinion and spur and setting the proper mesh.
 

Actually, this access panel came in quite handy.  During the first maiden test run after the rebuild was completed I noticed that the gearbox sounded very noisy.  It sounded like one of the gears was not round or the gear mesh was too tight and then not as tight as a gear turned, sort of like a pulsing grinding noise.  After removing the access panel from the side of the gearbox and looking at the gear mesh between the pinion and spur, I discovered that the pinion gear had a manufacturing defect.  The motor shaft hole was not drilled in the exact center of the pinion, so the gear wobbled as the motor shaft spun it around.  This caused the gear mesh to be too tight against the spur in one spot and too loose 180° in the rotation later.  I replaced it with a Robinson Racing steel 14T 32dp pinion I had in my pit box and test drove the car again.  The gear noise sounded completely normal and smooth.

During the test drives on asphalt, the Raider felt slow compared to other beginner vehicles except maybe the Tamiya RS380-powered Grasshopper.  The Raider has lots of power, but no top end speed.  The Le Mans Stock 05 motor is comparable to the Mabuchi RS540S in terms of basic performance, so I was a little surprised how slow the vehicle was in stock form.  Some of the slow speed could be attributed to the wheels/tires used in testing.  The outside diameter of the tires is slightly smaller than the stock tires.  According to the manual, an optional 15T pinion can be used, but that's all it mentions.  The gearbox motor mount has two sets of holes, one for the 14T pinion (holes A and D) and the other for the 15T pinion (holes B and F).  Although there is a slot in one of the motor mount holes used for the 15T pinion that could possibly give more pinion choices, the manual doesn't mention using it.  Going up one tooth isn't going to make a huge difference in speed.  Going to a faster motor would also help, of course, but for now I will keep the Le Mans Stock 05.

I purchased a reproduction body and wing from Team Bluegroove in Canada.  The wing is actually molded behind the rear of the body instead of being a separate part, so some care has to be taken when trimming both parts.
 

Now that the chassis is complete and operational, all that is left to do is paint and decal the body and wing.