Top critical review
16 people found this helpful
A great idea! Executed poorly. i won't let my kid ride it until I've finished engineering it.
on June 3, 2015
It's okay. With all of the over-the top reviews, I guess I was expecting more. However, there are some inherent engineering failures on this machine, and I was missing some parts.
1. I only got two bolts for 3 extension rods. Not such a big deal, but the threads were metric, and I was putting it together at 11 PM. Luckily, I found the right size from an adapter kit for my weed eater that I had just installed earlier that day.
2. As this machine is made to wiggle back and forth, I was surprised that there were no lock rings for the bolts. If you've had yours for a while, make sure to check them, I'm sure they aren't as tight as you put them on.
3. What did you put in the bearings? They barely turn. My advice: flush them out with acetone and dry, then add a light lubricant from a skate shop. It's not a car, it doesn't need this heavy duty grease. A wheel that barely makes it around with the same force as one that keeps spinning for a full minute - which do you think will be faster on the road?
4. So... the axles are bolts, which thread into the end of the rear pipe. Both normal threaded, but with a good amount of locktite added to each side. So if you change the tires in back, unless you add more locktite to the bolts, one will eventually fall off. Guess which one? The left one, of course, as the wheel spins round, counter clockwise, it will be gradually loosening the bolt. Again, with the back and forth motion of this vehicle, you are putting pressure against the flange of that bolt while trying to unscrew it. This is basic mechanical engineering, people.
And while there is a washer (aka "speed ring" ) on one side of the bearing, on the other side, the flange of the bolt is mashing down on the bearing. You use skateboard bearings, but it seems nobody on the design team has ever seen one before?
The axles are fixed on a skateboard, and there are speed rings on each side of the wheel to pin the center of the bearing and allow the outer ring with the wheel to spin on it.
5. Seems to me the wheels are a bit on the small side - this thing could go faster with some bigger wheels, or perhaps just one in the front.
This is something I haven't tested, but I feel right in this.
6. No foam padding for the bars where your legs and butt rest? I guess we could be thankful that we got anything, there was one piece on the back bar, which is fine to prevent chafing or brusing while you ... pedal. But the weight of your body is constantly on the bottom bars.
This is what I'll do with mine - fix the axles by threading, then welding them into place, leaving enough space for a wheel to be attached along with it's nut. Cutting off the head of the bolt, I'll then cut threads into the end, so that a locking nut can be attached along with a speed ring. That is how you make an axle on something that goes any faster than a slow crawl with a human in it. Then I'm going to put some foam padding over the bars I'm sitting on. Find it at any homestore, water pipe insulation is what it's called.
The machine is pretty beefy, if it wasn't, I'd simply send it back. So it seems like the initial thought was engineered correctly, but then there were some shortcuts taken, or some engineers replaced before getting to the final draft.