I'm totally new to RC Helicopters. Bought my 16 year old a U810 for Christmas to see if he had interest. Unit worked well for a spell, but after a ceiling strike (among other crashes) unit won't fly. It wont lift and spins the entire unit on the floor. Looking it over, it appears the top rotor is spinning slower than the lower rotor. Tore it down, but apart from a slight misalignment in the gears, nothing obvious. Thought I felt some binding, but that is cleared up now. Thought we had it figured out, but no joy.
Other Ideas? I'm not thinking it would be too smart to jump straight into lubricating as this unit hasn't flown much yet, but not sure what else to pursue. No obvious bent parts.
Hi Robert and welcome to WF. I never had one of those heli's but I can throw out an idea or 2, I guess.
Does it use 1 motor or 2 for the coaxial rotors? (I would assume 2, if it has yaw control.) If it's 2, inspect that the motors turn free. Just a hair wrapped on the shaft can mess things up at these sizes. Maybe even try to swap motors if possible.
Stupid question, how about yaw trim on the transmitter?
I don't know if this one has it, but one of the hobby-grade co-ax helis I have has a yaw sensitivity adjustment on it's circuit board.
Thinking about it, this might not be a mechanical problem. When first spinning up, the upper rotor may not spool up as fast since it has that flybar with weights to sling around as well as the rotor. (Did you check the flybar is not bent and still has it's weights?)
Just throwing some ideas out there. Are there spares available for that one? There are a lot of toy-grade helis out there, and unfortunately, they are kinda throwaway items when they malfunction. You have to step up to the hobby grade stuff at some point in order to be able to repair it and keep it flying. If the bug has bitten, maybe it's that time?
Hope something works out for you. Good luck and let us know how it goes.
Thanks for the ideas. Going to tear down again. It is a cheap unit. "Throw away" is an appropriate description, but learning opportunity could be too
He thinks its cool, but I can't really say the bug has bitten unless he's willing to do what it takes to stay with a repair (spare parts are available) - or at least I can't afford for that bug to bite lol. I definately could get into this hobby, but I have so many already I don't want to pick up another unless it provides a joint effort with my son.
The gear for the upper blade was slipping on the shaft. A carefully placed drop of super glue and he's back in business. Thanks for the reply and this forum. If he gets serious, this will be a great resource.