The selection of 1/24-1/25 scale motorcycle models is rather thin. There are some prebuilt diecasts available from Onyx and Two Wheels, but they tend to be hard to find and somewhat expensive.
Hasegawa, a Japanese model company, released 2 of the Onyx diecasts as model kits a few years ago. These bikes were 500cc Grand Prix racing bikes, a Honda NSR500 and a Yamaha YZR500. There are 3 versions of the NSR that I am aware of, 3 different riders representing 2 teams. The Yamaha is the Team Rainey bike ridden by Norrick Abe. All seem to represent the bikes ridden in the 1998 racing season.
The Hasegawa kits are highlighted by photoetched parts for the brake rotors and chain and sprockets. The tank and rear bodywork on these kits are diecast metal. They have a plastic frame, forks, seat, exhaust system, wheels etc. The slicks are nicely textured, looking more like a scuffed race tire than a brand new one.
Airfix has released 3 500cc GP bikes of their own. The NSR500, the Yamaha YRT500 and the Suzuki RGV500, representing bikes ridden in to 2000 and/or 2001 racing season. They have also released another bike, but, to my knowledge, it isn't based on a 1:1 bike. When I get my hands on one, I'll let you know!
These are all plastic kits, not a mix of diecast and plastic like the Hasegawa kits. I read an assumption that the Airfix bikes were modified reissues of the Hasegawa bikes. I took pictures to prove that this is not the case! The Airfix bikes represent new tooling but, unfortunately, do not include the wonderful photoetched pieces either. The Airfix tires are smoother and a bit softer than the Hasegawa version, representing a brand new, unused tire.
Here is a side by side shot of the Hasegawa Honda (in blue) and Yamaha (as cast).
Here is a similar shot of the Airfix kits.
Now for the comparison shots. I'll start with the Honda NSR500. The Hasegawa Honda is shown in blue, the Airfix in bare white plastic.
From this top view you can see that the Hasegawa version is noticeably larger than Airfix's rendition.
From the side, there are noticeable differences in the profile, particularly the shape of the gas tank.
The rear shot is, perhaps, the most telling. Notice the completely different look of the Airfix bike, which represents a newer version of Honda's NSR500 racebike.
On to the Yamaha's. Here, Hasegawa's diecast bike is shown in an as cast finish (almost. There is still a bit of residue from where I removed the bike's first paint job - I wasn't satisfied with my work.). The Airfix kit is, again, shown in bare white plastic.
Again, the Hasegawa version is noticeably larger. The tail section also has a different shape, representing changes to the 1:1 bike.
The profile shot reveals the same changes to the rear bodywork.
The rear shot further illustrates the changes to the rear bodywork, as well as the size difference.
The wheels are unique to each of the bikes, both from Hasegawa and from Airfix.
Right to left: Hasegawa YamahaYZR, Airfix NSR500, Revell Harley Davidson Dyna-Glide (shown for comparison). The Hasegawa wheel is, again, visibly larger than the Airfix wheel. You can also see the differences in texture, with the Hasegawa tire having a "used" look. Note the valve stem detail on the Airfix wheel
The frames are also quite similar, though the Hasegawa is, of course, larger. As a side note, the Hasegawa kit's platic parts are molded in a much softer plastic than Airfix uses. It is also black, in case you couldn't already see that. The footpegs are molded into each frame.
Here is the shining star of Hasegawa's racebike kits! The parts are common to all of the 1/24 GP bike kits, but they look incredible! The rear brake rotor is shown face down, mostly because I couldn't get it to turn over without opening the bag it is in. The equivalent parts in the Airfix kits are molded in plastic, hence they are thicker; not to mention the fact that nothing looks more like metal than metal.
Pictures of the fairings and etc. are coming soon, along with building impressions and, hopefully, ideas for improving the detail level. I am also investigating the possibility of converting some of these bikes into their street going brethren.........STAY TUNED!!!!