AndyCW

The increase in speed available from the L motors is evident and the increase in power from the newer receiver is awesome. I worry that we will be able to make models that are faster than the IR link. It becomes hard to keep a fast model within IR range and limits how fast you can go without having to upgrade to the RC controller and receiver. Congrats on 100 posts and the chasis looks like a good starting point for something great.

Seems interesting. I like to see WIP threads. I have to agree about the geometry of the front axle though. A four link or angled torque arm would correct it. The other thing I see is that as the front axles tries to compress it travels forward. This will inhibit its movement over bumps at speed. Looking forward to seeing the finished project. Keep us posted please. School starts for me soon too. Full time school. Full time job. Full time parent. Where does my lego addiction fit into this?

This means that the price premium that is being charged on bricklink will be less severe as the supply increases.

Just reduced the axle ratio to 3:1 and lubricated the drivetrain. Wow!!! There is still enough torque. It can still carry a wheel and spin its tires. The increased speed is causing the 8448 spindles and wheels to separate and the gear train is starting to pop. The next step will be to reduce to 2.78:1. This may also correct the popping in the portal hubs. I may have to go to the newer front spindle design to retain the wheels at speed. When it accelerates forward, it really "plants" the tires. It only is popping going forward and not when going backward. You can see the rear of the ATV rise up as the geometry of the rear swingarm tries to push the tires into the ground. Without porportional control, some steering imputs can cause the vehicle to roll over becasue of the soft springs. This MOC needs some serious work. Version one of this vehicle had the old receivers and 4.2:1 reduction. This configuration was weak. It was not worth posting. The new receivers really do wake up the RC Buggy motors. Can't wait for someone with some electrical engineering background to quantify the improvement these new receivers are providing.

The brushless motors that I am familiar with from RC planes are three phase. This means that they have three wires going to them and they require a different kind of speed controller than brushed motors. It seems possible to gut the PF chasis and install all custom pieces inside, but it is not likely to be a simple "sodder on this new motor" kind of swap. IMOH There may be another kind or style of brushless motor out there that would better facilitate this kind of "shananigans", but I am unaware of any such thing.

I don't know about less friction, but they allow a narrower track width and put the pivot point more towards the center of the wheel. The downsides are that they are rarer and do not have as secure of a connection to the wheel.

Having trouble embedding pics link to pic front suspension without wheel I used the spindles from 8448.

Thinking about reducing the gear reduction and seeing if it still has enough torque. I now see the use of the new axles on 9398. The axles I am using try to back out of the reduction hubs and there is not enough room for some retainers with the wheels I am using. The train controller may be in my future to control this with a little more finesse.

2 RC Buggy Motors 2 Rechargeable Batteries 2 V2 IR receivers 1 PF servo Independant front suspension Live axle rear suspension 5:1 Rear wheel drive(no differential) Better bodywork than my previous submissions. The front battle bumper is the key. The performance is outstanding. It can carry a tire and spin its tires on pavement. This is version two. The first one was an abject failure. Popping gears and not enough power. Redesigned drivetrain and the new receivers changed all that. Will take it out tonight for some offroad action and another video to demonstrate performance. This combination of parts will be going into another trial truck soon. Hopeully, the new receivers and servo will improve the performance I was able to get on earlier submissions.

I mocked up something like this earlier this year and was left unimpressed with the dimensions that resulted. The wishbones are 5 studs long, the center section is 5 studs wide, and the reduction hubs add significant wheel track width. Overall with the unimog tires it looked out of proportion. It looked too wide. I thought about sacrificing the reduction hubs and going with the 8880 wheels, hubs, and unimog tires. This would allow easier configuration of suspension geometry. Using non standard wishnbones may be the way to get the features desired within the scale desired. Couple this with a non standard differential configuration that allows the center section to be narrower. I remember someone using the unimog suspension pieces as lower control arms sometime in the past on here and this solution seemes quite well suited to Hummer suspension design, but it looses the reduction hub. To maintain scale with the unimog tires the track width may need to resemble the width of the 9398 crawler. Wow

Thank You Dluders. That makes everything pretty clear for me and hopefully the OP.

This a question that has been rolling through my head recently. We know how much current the motors draw because of Philo's research and we know the rule of thumb given us by lego, but do we know what the current limits are on the recievers and batteries. It seems that torque is a function of current draw and knowing available current draw before encountering the safety mechanisms will alow us to determine available torque in any given motor application. Prime example, we all know that the RC buggy motors are hobbled by utilizing PF architechture. The question is by how much. I aplogize if this is viewed as a highjack, but these questions may shed some illumination on the OPs questions. v/r Andy

In a fullsize car, you hold the brakes on while you are doing a burnout to "hold the car in place". In the annual motorcycle rally in Sturgis ND, they use chock block to "hold the motorcycle in place" during the burnout competition. Drag Cars have something called a line lock that allowes them to only actuate the front brakes to facilitate a burnout amongst other things. v/r Andy

You used to be able to get a v-10 in the Dodge Ram. It was based on the v-10 architechture of the Dodge Viper v-10, but tuned for truck duty. It turned out to be less suited to truck duty than the tried and trusted I6 cummins. The sound of those older 12 valve Cummins is unique. They even put a full viper motor in a street version of the ram. The relevant spots are at 5:18 and at 12:30.

Looks inspired by Caterham. Caterham Website Saw one IRL two weeks ago at a SCCA event. They're tiny. v/r Andy

I drive a 2005 6sp cummins dodge ram at work. It's nice and the funny thing is that it gets better mileage than you would expect. Down here in Texas, they drag race them. They can be surprisingly fast. v/r Andy

Good one. That made the neighbors a little sore. Best way to use up old tires I have ever come across.

dodge ram 2500 "There's a practical-and-it-feels-that-way 3.9-liter V6 that makes 175 horsepower, and at the other extreme, heavy-duty 2500 and 3500 pickups can growl with an 8.0-liter V10, good for 310 horsepower (305 for California). Tucked in between for good measure is a 245-horse, 5.9-liter V8 and a 5.2-liter V8 worth 230 horsepower. A macho 5.9-liter, 24-valve inline-six turbodiesel is available if you like loads of torque (450 pound-feet), low-maintenance and the overly loud purr of a diesel, plus have about an extra five grand to spend." Edmunds.com Can't wait to see it in action.

I used some of his design characteristics for inspiration. I tried laying the motors down to lower the center of gravity, but it raised too many other complications. It seems that there sometimes there are only so many ways one can invent a wheel. I also prefer my four links to the unimog suspension style utilized in the "panther". Yes, the bodywork is mostly an afterthought. Much more time spent on axles, geometry, and the chassis. I do not think that I am that good with body work so I copied Zblj's crawler body and modified it to work for my chassis. It is mostly "tippy" because of the location of the RC buggy motors. I have tried softer shocks and they would not stop it from rolling over. I also tried firmer shocks and they inhibited wheel articulation. It is a compromise. My last vehicle used PP tires and the weight of them helps to stabilize the chassis. Maybe the next iteration will be scaled to make it work with PP tires without looking cartoonish. It probably could use a grill. I could also stuff other lego tires into the unimog tires to try to improve traction. Thanks for an honest critique. v/r Andrew

Just finished putting together a video of my latest creation. It turns out that the Unimog tires don't have the best grip. Any input on ways to improve it? Thinking about doing a rally car kind of trial vehicle next. Any thoughts on that? v/r Andy

When I'm stuck, I take a break and will cruise the interwebs for sometime. The input of new ideas combined with the absense from building usually help me solve the problem or to figure out a work around. Sometimes I end up rebuilding in another manner so the original problem doesn't even come into play. Either way without an idea of your specific problems (pictures) we will be of little help. v/r Andrew

I've been working on a similiar concept. -4 links front and rear -PP tires -2 RC motors -geared 20:1 I keep stalling the motors.

brickshelf link Not public yet and they are big pics. Next phase will be to convert to RC buggy motors for propulsion and try to keep the same outward appearance. v/r Andy

The placement of the rear axle drive motor is one of the things that I like the most. It is comparable in height to the motor that is in the chasis. I have tried a version of the front axle that has the drive motor mounted in a similiar fashion and the steering motor mounted in the chasis. It has not worked out so well. Maybe the next iteration will be better. I'm most unhappy with the front steering mechanism. As far as I know, I am the only AFOL in town. There is a Lego discovery center in Dallas which is a 2 hour drive and they have an AFOL night once a month. I have shared my lego with some coworkers and the response was curiosity. I purchaced the 8043 when we were on travel and built it in my hotel room. They really liked it. The overwhelming comment was, "That's not the way Lego looked when I was a kid." Most people around here are more likely to build a fullscale truggy and go down to the dry river bed. I'll post everything to brickshelf before the day is out. v/r Andy

Taking what I have learned here and trying to put my own spin on it. -Powered by 2 PF XL motors geared down 5:1 -Steering by 1 PF M motor geared down 24:1 with 8t gear on rack -Rechargable Battery -Live Axles with portal hubs -Suspended with triangulated four links front and rear -Rear Axle has drive motor mounted on axle -Front Axle has drive motor mounted in chasis and steering motor mounted on axle -Power Puller Wheels -10 studs ground clearance -Works pretty good with Unimog wheels