Friday, October 24, 2008

New Dog Cart

My goal with this project was to build a training/tour cart for an eight to ten dog team which could carry two passengers. I wanted to have good braking ability and a decent suspension. I started by researching parts for small motorcycles or pit bikes since the wheels for those are similar to what I have on my existing carts. I couldn’t find much for parts that wouldn’t run me more than $1,000.00 just for the wheels and brakes. That would still leave me needing a solution for the suspension. At that point I started thinking about an ATV. I thought if I could find one for $200 - $300 dollars I would be way ahead of the game. I would already have disk brakes and a suspension. I placed a wanted ad on Craig’s List and received a few responses for dead ATV s.

This is the one I ended up purchasing for $300.00. It’s a older Yamaha Banshee 350. I was told the motor did a few years ago but smoked. Even though I was tempted to try and start it I didn’t and went right into tearing it apart.



Here is a picture of the frame with all of the stuff I didn’t need removed. It only took me about two hours to pull the motor, plastic and wiring off and get down to the bare frame. At this point I was able to see exactly what I had to work with. At this point I could still turn back; once I began to cut the frame apart with the hack saw there was no turning back.



Once I had the frame cut in half at the center I did a mock up to help visualize what the final product might look like. Being a woodworker by trade I found wood to be the quickest medium to accomplish this. Basically I was trying to determine what I would need for an overall length and still have reasonable space for passengers. My existing tour cart had an overall length of nine feet so that was my target. This cart is exactly nine feet long; however it looks longer because the nine feet if from wheel to wheel. The other cart is nine feet including a foot rest with the actually wheel to wheel measurement being about a foot shorter or around eight feet.



After determining the length I bought some square metal tube and started to weld the new middle section of the cart. I used 2” tube for the flat floor part of the frame and 1” square tube for the upper parts. It’s quite possible that it is over built but being a complete novice with metal working I would prefer that over having something that might break. I set up saw horses and level beams to construct the floor frame to try and keep it as flat as possible.




Once I had the center frame welded I tacked it in place between the two halves of the ATV. Everything seemed to work well so I continued to weld. As you can see in these pictures I also added bracing to strengthen the connection of new frame to the ATV halves.





Things were going well, the suspension and brakes seemed like they were going to work fine but the steering… That was a big hurtle. How do we get from a handle bar in the rear of the cart to the tie rods at the front? It took me a few hours of scouring the internet before I came up with a source for small rack and pinions. There is a company in Arizona called Desert Karts http://www.desertkarts.com and they carry a wide assortment of sand rail/ cart parts including steering components. The owner Greg was very helpful with explaining what I would need to accomplish my goal. He had a great understanding of the product as well as the ability to comprehend what the heck I was talking about. No small feat as even I didn’t have any idea what I was talking about. What we ended up with was a nine inch rack and pinion which runs off of a straight 5/8” tube to the rear of the cart where it connects with two universal joints allowing the steering to angle up 60 degrees for the steering column/handle bars. The only issue at that point was the fact that this set up didn’t turn the wheels a full turn unless I rotated the handle bar all the way around backwards. Greg suggested shortening the steering arms which I did and this greatly increased the turn amount at the front. He also sells a steering quickener which creates a 2 to 1 ratio in steering. That was plan B for me and it doesn’t look like it is necessary at this point.



This is a shot of the completed cart. I modified some of the original plastic so I would have fenders. Some of our roads/trails become pretty wet in the fall so I wanted to have something to keep water from spraying up on the cart. I made the seats myself. My neighbor does furniture upholstery and had some foam and fake leather scraps. They have a plywood core. That pretty much did it other than a little tweaking here and there such as suspension, steering and brake adjustment. She’s pretty well dialed in now and goes great. It rolls along well and came in at less than $1,000.00 if I don't include my time. Not bad for a full suspension, disk brake cart.. I’ve been running a ten dog team with a minimum of 300 pound loads and the dogs don’t have any trouble pulling it up our hills. I do have the tire pressure up around five pounds which decreases the rolling resistance. The finished cart probably weighs around 250 to 300 lbs. I am able to completely stop a ten dog team with it; the brakes are fantastic. To hold the team I just made some low tech clips on the handle bars which hold in the brake levers. I think part of the braking ability is due to the large contact patch achieved with the ATV tires. They are much wider than the pit bike or motorcycle tires. Feel free to email me at: ken@peacepupsdogsledding.com if you would like any further information.

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