The reason is, that yank-eliminator (what you use to start it with the drill) comes with an incredibly low quality one-way bearing. This bearing will quickly tear up. I have had 2 and the are POSs. My first broke the second day out. I called Tower to return it and they said no-can-do. I would have to take it up with HGI, the manufacturer. I left 8 phone messages and sent over 10 emails. They have number you can call to talk to anyone. They never returned a call or email. I have heard many others say the same thing. Just a few heard back from HGI, who told them that they did not hold it perfectly parallel and it was their fault it broke. The problem is, it is IMPOSSIBLE to ALWAYS keep the drill parallel, as the truck tends to twist a bit on the compression stroke.

For the same price as the yank eliminator, I got a hand-starter with a rubber donut adapter and it works GREAT. Hook it up to a battery, I use my car, and bump the flywheel through the chassis. It works like a starter box for less than 1/4 of the price!

http://www2.towerhobbies.com/cgi-bin...&I=LXJC35&P=ML - Hand starter, 19 bucks!
http://www2.towerhobbies.com/cgi-bin...?&I=LXL402&P=V - Donut starter adapter, 4.50!

One P.O.S. Yank-elim. costs 25 bucks!!