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Reverse gearbox (again)
Smooth Torquer - 19/4/04 at 12:33 PM

Hi all,

Im sure that this has been discussed before, but now that BEC are becoming more commanly built i was wondering which reverse box solution people had found worked best?

Thanks in advance

Sam


ChrisGamlin - 19/4/04 at 02:22 PM

You might want to have a hunt via search, as Im sure there have been a few lengthy threads on them before.
Basically though, for a Locost type car you have 3 choices

1, Mechanical reverse box situated in the middle of the prop
2, Electric version which either drives a gear off the sprocket or off the diff at the back
3, SWMBO power (aka the helpful passenger pushing technique)

Option 1 is more widely used but most designs seem to be weak. Some people get away without any problems, but Id say the failure rate is too high considering the investment required.

Option 2 is used when reverse is a necessity (racing for example), but you dont want the single point of (some would say likely) failure. An electric reverse isnt as powerful as a mechanical one, and you need to put up with a car sounding like a milkfloat in reverse, but the benefits are that you dont get the additional vibration etc usually associated with having a mech reverse box in the middle of the transmission tunnel.

Personally Ive opted for option 3, in 2 years of track days and driving on the road (approx 2-3k a year on road) I can only recall once where I really wished I had reverse. On some other occasions I guess it would have been nice, but rolling the car around is really easy so its no hardship and a small price to pay for a more reliable (and cheaper) drivetrain.

HTH

Chris


Smooth Torquer - 19/4/04 at 04:43 PM

HEHEHE Option 3 sounds good to me

I dont really like the idea of having a weak point in my transmition just to backwards occationally

I'll do some more searching and see what i can find

Thanks very much

Sam


Lightning - 19/4/04 at 10:59 PM

I was considering cutting the floor out of the passangers side and having an inducator light on the dash saying REVERSE. When lit the passanger pushes back on the ground with her feet AKA Flintstone style.
Should work


thekafer - 19/4/04 at 11:23 PM

...... with her feet......



I suspect you'll experience a severe whinning sound.........It's brilliant!!!

Fletch.