This NES game is missing from almost all lists for people looking for a complete NES collection. It is unlicensed but was available
for sale in the USA. The cart is now somewhat rare and the full system is much more rare. A complete system includes the cart,
interface box to the controller ports, manual, bike trainer, and handlebar display. A NES console with the lockout chip disabled
may also have been available but no pictures of one have been seen. The cart has no lockout chip or lockout defeating circuits so
it must be used on a top loader or a system with the lockout chip disabled. Electrical power is used to put more resistance
in the flywheel in the trainer. The speed and power output is transmitted to the NES through the controller ports where the RacerMate
Challenge II game reads it and displays it on screen.
The game itself is slightly more entertaining than watching TV while biking. It mostly displays the usual stats like speed and power
output. It also displays the graphics of another rider you are racing against. You can set his speed then try to keep up. Courses
like sets of mountains can be selected for more challenging races. I havent found a way to crash the bike or the other rider yet...
Without the interface box, handlebar display, and trainer this game is pretty much unplayable.
The cart itself has a unique case shape and a custom mapper. To make removing the cart from front loader easier the cart has a "handle".
The cart also has four screws with hex nuts to hold it together. There may have been a Tengen style case for some of the earlier carts.
Inside is 64KB prg rom and 64KB chr ram. The saved games are stored in the chr ram and backed up with a standard battery. Program data
is not erased when the battery dies. Bank selection is done by latching data bits on writes to $8000. D0-2 select the prg bank (8 banks
of 16KB) and D3 D6 D7 select the chr bank (8 banks of 8KB).
Download the CopyNES plugin to dump the prg and chr to a .nes file. Mapper is number 168.
The prg data is arranged exactly like it is on the rom chip, so it can be burned to a new chip and put on the cart. The chr data may not
be arranged the same as it is physically. Tile data is copied from prg to chr, so the saved chr data is not needed. I can write a
quick program to rewrite the chr ram if anyone has valuable saved games.
The known versions from a digitpress thread are:
Bike trainer mount.
Handlebar mounted display with control buttons.
Interface box, has two ports for multiplayer.
In game screenshot.
RacerMate cart front.
RacerMate cart back.
In game graphics.