SlideWRX 760 Posted October 3, 2021 I bought this for my son last Christmas. He was 6 at the time. He has driven it a little, but mostly it sat around as other things kept his attention. Since I got pulled back into RC this summer, I've been driving my buggy, and finally got him out at the same time with this. That showed the deficiencies of the chassis; not just speed, but complete lack of suspension. Literally no suspension, and the tires are rock hard foam with no compression. They are there specifically to let it run in the water; they keep it afloat. I liked better the idea that it would go through deep puddles and snow and such without issue. Anyway, I'm taking it apart to see what can be done! The start of dis-assembly. everything is held together with the same size self tapping screws. EXCEPT for the roll cage. That clips to the chassis. Just have to give it a strong pull and it pops off. The 'wheels' are solid foam, like a styrene cup. They have a rubber strip on the outside, I assume for smooth road traction. This is the chassis. note, no suspension. Also, nice seals around every opening to the electronics. remove these four screws on the chassis first. it allows the geartrain to be pulled off as one piece, and gives easy access to the screws on the backside. Here is the geartrain.no seals around it. You may surmise that the steering is like a tank; one side goes the one speed, and the other side can go a different speed. Slipper gear! One going to each wheel. Here is the outdrive the wheel attaches to. It is a long 7.4mm hex. Does anything out there fit that? I am assuming not. If I want to run rubber tires on wheels, so I get *some* sort of suspension. I'll need to make an adapter to 12mm. The battery and one of the motors. there is one driving each side. It looks like a 280 (2435) size motor. the 11tooth pinion appears to be pressed on. Summary for upgrading: -The only way to get smother running is to go for rubber tires. The wheels here only match up to the foam tires, so they need to be replaced together. I think a 7.4mm hex to 12mm hex could be made. -for more speed, either upgrade the motors, or add another battery. It is a 6.4 LiFe pack; I could theoretically solder in another battery to get it to 9.6 volts and hope the electronics don't otherwise short out. What do ya think? Share this post Link to post Share on other sites
SlideWRX 760 Posted October 20, 2021 Success! I made my first 3d printed shape. This is an adapter for the 7.4mm hex coming out of the gear case, to 12mm for most RC wheels. I learned a couple things - I measured the hex I was sliding the adapter onto (7.4mm), but didn't check the original wheel part to see what size it was to slide *onto* the hex (7.7mm). So I made them 7.4mm and they were exactly too tight. 7.5 or 7.6mm and I wouldn't have needed to file down the inside of these adapters to fit. 20 minutes later, all four adapters fit. Also, I created 1 model of the adapter, and ordered 4 of them. The pricing is automatic, so I'm guessing I was charged for 4 prints, when I should have made 4 parts in the model, and ordered 1 print. Anyway, I installed the new tires/wheels and gave it a quick spin. It didn't tip over, but I'll have to have my son run it during the day to see how it goes. The tires are about the same size (monster truck), very soft, with a foam insert for strength. It gives them ~1/2 inch of compression, where before I had zero. Share this post Link to post Share on other sites
SlideWRX 760 Posted October 23, 2021 It is definitely a LOT better! I got the son out driving it around the house several times, and bouncing off of sticks or roots really didn't upset it much. It bounced, but tended to stay upright. It used to flop over quite a bit, requiring my son or I to run over to it to right it. The problem now, is the the rubber wheels offer too much traction - the tank style turning doesn't work well in the grass when stationary. It will turn about 45 degrees then stall sometimes. If it is moving forward at all it wasn't an issue. I think maybe a couple more outings and the kid will learn some better control and it wont really be a problem. The original wheel, for comparison: 1 Share this post Link to post Share on other sites
Frog Jumper 3605 Posted October 23, 2021 What’s the wheelbase on that shark truck??? Share this post Link to post Share on other sites
Frog Jumper 3605 Posted October 23, 2021 37 minutes ago, SlideWRX said: It is 200 mm. Dang. Too short for the ORV… Share this post Link to post Share on other sites
SlideWRX 760 Posted October 23, 2021 Lookin' for a shark rock- crawler? 1 Share this post Link to post Share on other sites