I Want An Inexpensive RC Dirtbike, Do You?

[Jason Sams]

I've been a motocross and supercross fan for years. I love riding my bike too, and wish someone would come out with an inexpensive RC dirtbike. There are dirtbikes out there, but I think they could be done better and be more affordable. Do you think an affordable ($200-$350) RC Dirtbike would be a hit? I think a bike done right would have Slash like success, especially if a high RPM gyro kept the bike upright at really low speeds.

Check out RC Car Action contributor, Lito Reyes, Ricky Carmichael bike at Hot Rod Hobbies.

http://www.youtube.com/watch?v=AO-BGIoYcgY

[ducati777]

I'm pretty sure gyro's don't actually use spinning wheels anymore. Its all piezo crystals.

But yea, a dirtbike would be a lot of fun. Have it use 8th scale buggy tires, and it's gotta have a chain drive.

[rccardude04]

They use a giant spinning wheel in one of the actual wheels to mechanically keep the thing stabilized. Not a heli gyro that would modulate steering to keep it upright.

-Eric

[ducati777]

thats pretty clever.

[desfjr1300]

I'd buy one in a heartbeat but I don't really see the need for stabilization at low speeds...when was the last time you saw the real thing running at anything less than WOT?:D

Weighted wheels (like the Kyosho HOR's) work well enough to allow running at a little less than walking speed, but if you were really serious you could install one of the flybarless heli systems for multi-axis stabilization, like Mikado's Vbar. Of course that's gonna take it right out of the "affordable" category.

But make it BIG! I'd like to see 1/4 scale or better.

[kwkride]

I think that a hobby grade dirt bike would be awesome!

[Jason Sams]

At some point one will be on the way. It's only a matter of time before one of the larger manufacturers figures everything out. I've said this quite a few times and will say it again. The first manufacturer to get an inexpensive dirtbike right will have a "T-Maxx or Slash" on their hands in terms of success and sales.

I've talked several times to Car Action's contributing editor, Lito Reyes, who is an avid RC motorcycle enthusiast about what a good dirtbike would need. Here is what the two of us have come up with.

- Lightweight lexan rider (keeps CG lower)
- Powerful gyro that allows the bike to stay upright at low speeds (big help in tight turns on tracks)
- Durable, yet mini-pin tires. The larger lug tires are great for grass and high traction surfaces, but on loose dirt they don't hook up.
- Several molded components that are cheap and easy to replace.
- It must look like the real thing!
- Front forks that offer good dampening. Friction bouncers don't cut it!
- A waterproof brushless system would be nice.
- Alternate colored plastic kits to simulate the big five (Honda, Yamaha, Kawi, Suzuki, and KTM)

[kwkride]

So what do you think of the Duratrax dirt bike?
Do you think that this will fill the need?

[andystoybox]

I think once Traxxas makes it, 80% of us will be happy. 10% of us will wish it didn't come with Traxxas radio gear and the other 10% will want it as a kit.

[Racer Rob]

lmao isn't that the truth!

I was checking out the Duratrax dirt bike, very interesting. Would like to see one run first hand.

[Jason Sams]

I was able to rip up an down one of the aisles at the recent IHobby show with the Duratrax DX450. Check out this Friday's Radio Control Show for a clip of me driving the new bike. I have to say that I was thoroughly impressed. The bike was really stable and would even fight to stay vertical when coming to a complete stop. The gyro works well and this bike is much easier to drive than others I had the privilege to run. I am totally into the DX450 because I am a supercross and outdoor national fanatic! I plan on reviewing the DX450 in the February issue of Radio Control Car Action. I will also shoot plenty of video footage at the track so you can check out it's handling capabilities.

[Lito Reyes]

Like Jason said, the DX450 looks to be the real deal. I've been running one for the past month on all sorts of tracks and surfaces, and with some setup, it can totally be raced on even a small, tight track.

Even though I've already had a lot of stick time with it, I'm looking forward to reading what Jason (who is one of the most well-versed off-road guys on the planet) thinks about it and his experiences up in NorCal with the bike.

[Lito Reyes]

desfjr1300: A spinning gyro is an absolute necessity in a dirt bike. Superbikes, like the Thunder Tiger FM-1e or Nitro Ducati Desmocedici can get away with just the gyroscopic effect of the wheels to keep it balanced because of the traction on the tarmac. Dirt is much different; once you break traction, there is nothing that will get you back upright. Now, I have run my road bikes with road tires on hard-pack dirt ovals (think speedway bikes) with great success, but that only works when the dirt is cement-like and practically blue grooved. I was able to do some controlled power-slides, hanging the tail out every now and then, but it was pretty hairy.

Anyway, that video that Jason linked to above was when I was testing a brushless motor-based gyro in an old Radio Shack Ricky bike. I used an old 35A heli brushless ESC controlled by the third channel on my radio to get the rear-wheel gyro working. The great thing about it is that because the gyro ran at a constant speed the whole time (determined by my setting on the radio), I had the same amount of stability at the end of the lap as I did at the beginning of the lap. You might be wondering why that makes a difference. Well, with the stock Ricky, a stock ARX-540, or even the Duratrax DX450, the rear wheel gyro is driven by gears in the wheel. With the Ricky and the ARX-540, the gyro turns at a rate of about 5:1 and 4:1, respectively (I don't know what the ratio on the DX450 is yet). So whenever you are on a straightaway, the gyro is "recharged", so to speak. As you navigate around the track, the gyro slows down, and every time you lean over, it slows even more.

I feel that the key to racing these initially will be running on tracks that aren't so big that the gyro slows down too much. Turnmarshalls will also have to remember to hold the rear wheel up for a few seconds to let the driver recharge the gyro before launching the bike back into the fray. Now, I feel that long-term success might be dependent on getting a constant-rate brushless motor gyro like I have in my video. I'm working on that, I promise you...