I just got Moto Roader (the first one) and after I worked out the handling, I'm really enjoying it. I'm trying to figure out the balance of upgrading different parts (I feel if I don't win, I've lost).
An interesting thing I found out is that you can go to whole new different tracks by holding button combinations:
http://www.gamefaqs.com/tg16/589037-moto-roader/faqs/38934 - might apply to yours too:
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-= Alternate Race Courses =-
-==========================-
The KEY reason why I'm writing this FAQ - I've been hunting online for
the alternate race courses available in MotoRoader, and haven't found any.
Drat. So while I still remember a few of them, I'm gonna immortalize 'em
on GameFAQs. Each course has 8 heats, and each vary in the number of laps.
These were taught to me by a fellow PC-Engine enthusiast back in the '90s.
* Default Course
Just press Run.
Overview: Very basic course, and the best to run when introducing newbs.
* Suburb
Hold Down I + SEL then press Run.
Overview: Hands down the most challenging and difficult course *ever*.
I do not think I've ever completed this course while using grenade launchers
at every round. The first heat is extremely long, very difficult to
memorize and trap ridden. The other heats vary in length and difficulty
from simply annoying to verily a strain on the senses.
Most of the times, I will purchase a Gas Tank... just in case
* U.S.A
Hold down UP + I then press Run.
Relatively easy course, about the same difficulty as the default course.
* TRAP Course
Hold down I + II then press Run.
Fun! If the whole group of players at least knows how to control the cars
properly and know how to use the gas tank. Heats are average length, but
the placements of traps and layout is very challenging, at times funny,
yet not as annoying as the Suburbs. No warning signs for course obstacles!
* Other courses?
I cannot remember if there are any other courses (Hey it's been more then
a decade!!!!) If you do, please email me?