Off Road Hybrid Buggy
 

I am in need of an off road vehicle similar to a Yamaha Rhino, but lighter, smaller, and preferably Electric. I've looked at Electric Golf Carts, but they are too big and heavy. I have narrowed it down to taking a couple of small dirt bikes, remove the engines, tank, seat, upper frame, lengthen and attach them together, and put a couple of seats in it and electric power. For the final vehicle, I'm thinking Golf cart motor, and Smart Battery Lithium Ion batteries. The prototype can be done with a couple of Razor MX 650 kids electric Motocross bikes, as they are prevalent and fairly cheap. Using those, the whole thing could be done for around $1,000. If that proves out my idea, I can build the good one with a big motor and Smart Battery Lithium Ion batteries, and add a Yamaha EF2,000iS Generator, for battery charging. Your thoughts please!
Thanks...

sounds like a good project.nare you going to lower it or leave it taller.

Yes I will lower the seat height. Cut the top tubes off that hold the tank and seat, basically make it like the "Project 100" in the Motorcycle and Scooter page. Seat height will be maybe a foot higher than the bottom tube under the original engine, room for the batteries. There will have to be either added bottom rails, or a top tube-tubes (more likely) to add structural stiffness.

Here is where I am at on my Off road electric buggy so far. It will lean into the turns by way of the chassis hingeing in the middle when the front wheels are turned. I'm hoping for as good as or better handling than the current UTV's, like the Polaris Razor or Yamaha Rhino. The frame will be made from aluminum square tubing. I welcome all thoughts on this. Thanks!

http://ecomodder.com/forum/attachmen...2&d=1440716459

http://ecomodder.com/forum/attachmen...3&d=1440716621

Sounds like there isn't much of the original motorbikes left. And you have to sort out the steering. Consider this (the pictures date from 2004, in Glenwood Oregon):

http://ecomodder.com/forum/member-fr...ectric-t-1.jpg

http://ecomodder.com/forum/member-fr...ectric-t-3.jpg

Golf-cart rear axle, side-by-side seating and the well-proven street rod style four-bars and solid axles.

That IS cute! My goal however is; light weight, good ride off road, fit in the back of our truck with the tailgate up, and good off roading capability. Not too much to ask, huh? I know where there are a few machines just sitting around unused, asking to be repurposed, but I have no way to get to the moon and back! The Moon Buggy was an actual inspiration for this.

OK, I've taken my project back to my page I started a while ago, I had been distracted by Number 21's page where I had been posting, but I'm back here now. The latest is, I have done some adjusting to the drawing based on more accurate measurements of the bike chassis parts, I have purchased a Yamaha generator which will served double duty for our camp trailer and as the "Hybrid" part of my electric buggy, I have measured the electric drive train from the golf cart and added it to the drawing, and am bidding on a battery from a Chevy Volt, which I also drew up and added a pair to the drawing. I have obtained some 6061 aluminum bar stock to make upper fork, steering brackets out of, they will have to go to the machine shop to get the fork tube holes milled out. When it warms up some, I can get to the golf cart for disassembly. To be continued...

.

Warmer...???

Lol...

:)

http://i536.photobucket.com/albums/f...psyzhztq8u.png

>

Ha Ha Ha ...Well, the Weather Channel, really does not pay much attention to the Southwest, unless we have a disaster, typical of the Major News Networks based in the East. Today barely got in the 50's, with no sun, wind, and the mountains surrounding town are topped with snow, and more came down this morning. My workspace is a metal storage shed with no electric or heat, it's 43 right now with a breeze, 62% humidity...Brrrr.

nvm

nvm?

OK, I have finally been able to get back to my Off Road Electric-Hybrid Buggy project. Most of my thoughts and comments about it in the past were at Number 1's, "I want a Hybrid Side BY Side" page, which I had mistakenly taken over...sorry Number1!
Anyway, I have the golf cart stripped down and need to sell or junk the carcass. It's an older Club Car with a good aluminum frame and a decent body, with front and rear suspension, tires, and seats. I take $100 for it if anyone is interested OBO, and will be heading to the Jackson MISS area around the end of May, from Tucson, so I could bring it. As soon as the cart is gone I will start bolting the bike frames together.
Just to recap, I am taking two Yamaha YZ 400 chassis and will weld or bolt them together to make a two seat buggy, 4' wide at the widest part ( the front forks). I am then going to narrow the golf cart rear axle and install it where the bike front sprockets were, driving the rear wheels with the stock chains. The front forks will be connected with a tie-rod and use the golf cart rack and pinion box for steering. I will power it with "a" 48 volt Chevy Volt battery section, which I have. After the bugs are worked out with the drivetrain and the buggy is driving, I will get a another few section of the Volt Batteries to extend the range, and I'll get the motor hopped up for more speed. The Goal is 45-50 MPH Max, and 50 mile range. Anyway, enough for now, like Arnold says...I'll Be Back! Thoughts and comments are always welcome...BYE!

Here are the latest photos of the project and he golf cart frame I'm getting rid of.

As an engineer, I can see a couple of places where the tubular frame design needs some adjusting. You need to make sure that you have enough reinforcing tubes in the load bearing areas so that any two tubes have a third tube connecting the ends to make a triangle. Triangles are the most rigid shape possible with thin wall tubing. Pay special attention to under the seats through the rear suspension supports. The rear presently looks cantilevered, which will be a weak spot in the design.

Bill the Engineer

Yes Bill, thanks. This was a very early "Sketch" that I did and by no means refined. It has a pivoting frame which leaned into the turns which has since been down away with, in favor of having a Cambering Rear Suspension, if I want it that complicated.

http://www.autospeed.com/cms/article.html?&title=Zero-Cost-Modelling-of-SpaceFrames&A=112924

• Bungee cords?
• Coil-over shocks?
• Elastomeric snubbers?

Front, the factory Yamaha MX forks, in the rear I'll probable start with the factory Bike coil overs, though they are heay and designed for way more action than I am planning. I've looked at Midget race car torsion bars, and would prefer air bags for weight reduction? The last two methods would require separate shock absorbers.
Thanks for the ideas!

Repurposing both motorcycle frames seem kinda unsuitable if you want a conventional seating position.

Bungee cords are good enough for light planes on grass fields. It'll weigh less than a Piper Cub, right?

On the MX Bike frames, the top tube will be done away with, and diagonal tubes added on each side, seats about where the rear coilover is mounted now. As far as the bungee cord idea, I like the weight saving idea, but the linkages involved would add complexity. I'm really looking at an airbag mounted to the bike swing arm, but I'll figure that out when I get the two frames connected. Here is a more recent drawing of the buggy, with the forks, batteries, swing arms, and golf cart drive rear axle to scale.

BASF Polyurethanes North America :: Cellasto^®

The snubbers I need for my Westfalia trailer come in 400kg and 800kg ratings.

I kinda like the snubber idea but I am going for long travel suspension and a soft ride, which I think will be easier with the existing suspension design. I got rid of the golf cart parts I didn't need and have the bike chassis's back about where they will be when connected.

This Sat, I started getting the two bike chassis connected, these are temporary obviously, but it will allow me to get all the dimensions set and the frames plumb and square. I can also start on the steering bracket fab. It is quite amazing how stiff these simple attachments made the buggy. Once the frames are exactly where they will be located, I will be able to cut down the golf cart differential, and get the axles shortened. The diff is in the basic location that it will be in when finished, except raised up to the centerline of the swing arm pivots. Baby steps, but progress none the less. The storage building is very hot as it's about 103 here, so long days working is not feasible yet.

Well...After a long break due to a kidney transplant, I am slowly back to work on my Electric off Road Buggy. I have acquired some steel framing studs and track to use for the frame construction. I chose this material due to its light weight, corrosion resistance and mainly for the fact that I can build it with battery tools at this point, as I have no electricity in the storage unit I am working in. I am using self tapping screws initially and later I'll probably replace the screws with aircraft rivets. It's amazing how with just a few screws connecting the two pieces of track together, the structure gets quite strong, compared to how flimsy it was without connectors.
I got the bike frames on a jig and cut them apart. The photos show the general layout of the front forks and the swing-arms. The golf cart axle will be located in front of the swing-arms and become a frame member. The drive sprockets will be mounted on the axle studs. Here are a few photos of progress. Hopefully I can make updates a Regular thing...!

Here's hoping...

Glad to hear that kidney transplant went well...and you're well.

Thank you sir! It's been a tough haul this last 9 months....! I'm just now starting to have the energy to do semi hard work, with lots of breaks.

I started figuring the seat layout, the supports of which will be the rear spring-shock mounts. I have some AirLift air bags I am going to use for the rear springs, and then use some light weight tube shocks mounted to the swing arms. The factory coil-overs are very high tech, but fairly heavy, and way more than I need. I am not going to be racing this...much. Weight is my number one concern. I am still trying to find another long side golf cart drive axle and housing...Ebay has not been very friendly, nor has Google or Craigslist.

Got an hour and some in today, braced the seat mockup and shortened the wheelbase based on the seat position. Looking for some main frame tubing, guess it's an odd size, 1.5" x 3.5" x .120 wall, as soon as I get it I can take the head tubes off to get the excess material cut off and the new main frame pieces welded on... after building a jig to hold the forks in place. Still trying to find another Long side axle and tube for the golf cart drive axle....

Are you considering some sort of diff locker or eventually a selective rear-wheel braking to emulate manually the effect of a limited-slip diff?

Yes, I have been thinking about that some, from the start of this project. The brakes are independent, so having them selectable would be pretty easy. I have heard talk of a Posi-Locker for GC diffs, but that is not a priority right now, and I'm not real sure I'll need it, on the kinds of roads I envision we'll be on. But, Thanks for the input!

Assuming that you're going to use a regular pedal control for all 4 brakes, when I mentioned the selective braking for the rear wheels I was thinking about the setup used in some dune-buggies and other Volkswagen-based off-road vehicles, which had 2 small levers parallel to the parking brake lever, each one attached to one of the parking brake cables. However, since you're using hydraulic brakes with calipers that don't seem to have a provision for parking brake, you might work around the hydraulic lines...

Yes, cutting brakes, I remember them well! The plan for brake hook up was to mount the two rear master cyclinders next to each other, with Pull cables connecting the MC pedals to the front main brake pedal. It would not take much to add a couple of handles to those cables, id think. This is sort of how our '13 Tundra's limited slip rear axle works, using the anti-skid and anti-lock brake computer to prevent rear wheel spinning. If a wheel starts to spin, it applies some braking to that wheel. Not a Detroit Locker by any means, but very smooth and discreet.

An hydraulic cutting brake uses one push/pull lever for control.

But this project has an individual master-cylinder for each wheel, while it doesn't seem to be the case in most of the vehicles fitted with a single-lever hydraulic cutting brake.

True! I could use a mechanical linkage to hook up to the two rear brake cables, using two levers. Being that the "GC drive axle" is parallel with the rear wheels, there "should" be no torque bias at the drive wheels, as is caused in a std differential, having the driveshaft perpendicular to the axel... so hopefully both rear wheels will drive equally! I'll probably have a harder time balancing the four individual brake systems, so it stops straight!

Just a remind: the J40-series Toyota Land Cruiser had its parking brake at the transmission, with an independent drum at the output shaft of the transfer case. Maybe you could keep the stock brakes of the golf cart axle and use them as parking brakes and also to emulate a diff lock without increasing the load on the service brakes. And it would also become effective as an emergency brake.

That is a good idea, if I was not trying to cut all the weight possible!

There are always some compromises, and concessions to be made...