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LMaxwell
08-10-2013, 02:24 PM
Hi All,

I'm building my first trike from bits and pieces. It works well enough but I've been trying to free up the pedals from moving backwards when it has to be pushed in reverse and have yet to find a solution.

That's why I'm here. If you can help me, perhaps I too can one day contribute to resolving problems for others through my own experience.

Cheers

Lucas

darnthedog
08-10-2013, 06:12 PM
Welcome to the Group Lucas
As I replied before, all bicycles will have the pedals go backwards if you roll the bicycle backwards. It is due to how the freewheels and cassettes work. It has nothing to do with the AZ plans and there generally is no clutch as the bicycles cannot be pedalled backwards for power. Only forwards. Hope to see pictures of your project soon.

Tradetek
08-11-2013, 12:00 AM
Ditto to what DTD said. If there is nothing resisting the reverse rotation of the cranks/pedals when pushing the trike backwards, the pedals/cranks will also rotate backwards.

If you meant to say something different, please describe in more detail, or better yet... shoot a youtube video and share it here so that we have a better understanding of what you are trying to describe.

Also, in the future it would be useful if you indicated what plan you are building from because it could make a difference in the responses you get back.

Bill

pete
08-11-2013, 06:04 AM
welcome to the site.

Ticktock
08-11-2013, 08:19 AM
Hi Lucas,
as I said before, we are having a problem understanding why this is a problem. Bikes have been this way for over 100 years. There may be a way round it, but it really does depend on why its a problem, and what trike/ transmission you have.
So without more info, I can't offer any meaningfull suggestions.
Steve G,
beijing

LMaxwell
08-12-2013, 03:04 AM
Hi Gents,

Many Thanks for the welcome and replies.

It's not really a problem that I have as you've all pointed out, it's a challenge. Disengaging the crank will allow a brushless motor to reverse the trike without interference to the feet. We have a 1000 watt 48 volt Magic Pie ready to roll. I'm guessing there's no trike clutch anywhere on the market. Please do correct if you know of such a thing or I'll have to invent it, somehow ;-)

Ticktock
08-12-2013, 07:27 AM
Now I have an idea as to what you want to do, it makes more sense.
If you can post some pics of the transmission/ frame set up you have, I may have an idea on that one.
Steve G
PS If you have a rear derailer on the back wheel, you cannot drive in reverse.

darnthedog
08-12-2013, 09:21 AM
Lucas
If your not doing anything special while going backwards other than to back out of a parking spot. Your max reversing will only be a length and a bit more before having to go forward again. Seems like a lot of brain power for the small period of time. However if you have something special in mind going backwards feel free to research it. A couple ways to do it would be 1) disengage the chain from the rear gearing. Or 2) jack the rear wheels off the ground while backing up.
If your build based off one of Atomic Zombie Delta trikes, you might consider using lawn tractor clutch mounted to the axle. Or that of a motorcycle. But then your sort of going to have to piece it together as I have not see any of this done. Just a couple ideas that popped into my head once I read your intentions. Good luck and please post some photos of your trike.

Ticktock
08-12-2013, 10:47 AM
Hi,
I may have jumped the gun with the PS comment!!! If you have a hub motor it will drive backwards ok if you can make it go backwards.. just that you can't use the bike chain to drive in reverse with a derailer.
Hope that sounds better. I knew what I meant! Just did not say it right.
As I said, more details will help try to find a simple solution.
Steve G

Tradetek
08-12-2013, 08:18 PM
Ummm... guys, unless I missing something because I haven't done anything with hub motors, this isn't a problem.

The backwards pedal action Lucas sees when pushing the trike backwards is simply friction in the frewheel/hub. Any resistance on the pedals will cause the freewheel/hub to engage and simply prevent the pedals from going "backwards".

Bill

Ticktock
08-12-2013, 09:13 PM
I think I may have upset things with my quick, but not accurate answer! Its two separate issues here-or even three if you make my mistake.
The peddles turn back, as you rightly say, because they are being driven by the freewheel doing its job. A hub motor can be made to drive in reverse (don't ask me how--not my department).
And when it drives backwards, the peddles turn backwards, unless there is a means of separating the drive train somewhere. On a Celta this may be possible--much harder on Tadpole.
I slipped up because I forgot Lucas is using a hub motor, assumed the chain was doing the driving, and , in those circumstances, said it won't work with a rear derailer--which it won't.
But it did tend to confuse the issue until I realised what I had really said did not fit the plot. The bile will roll backwards with a rear derailer, but not be driven backwards by the chain.
Hope that clears it up more than it confuses.
Steve G,
Beijing