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Re: Runner Yokomo Build

Posted: Tue Mar 01, 2011 8:00 pm
by Justjoe
To answer the Brake question...The one way main pulley only eliminates the braking on the front wheels. The pulley does not freewheel the rear as the belt is still directly driven by the spur gear.

Re: Runner Yokomo Build

Posted: Thu Mar 03, 2011 8:41 am
by slapshot1979
Maybe I didnt type it properly, The robinson spur gears I have with the smaller pulley fixed to it have a 1 way bearing installed so... when the motor is driven it drives the spur which is connected to the shaft and 2 pulleys for diffs. when you put in reverse the spur freewheels and nothing is driven down the line shaft.

I think I just awnsered my own question. Why would they make something like this.

Re: Runner Yokomo Build

Posted: Thu Mar 03, 2011 8:50 am
by scr8p
because when you "race" you're not allowed to use reverse. one-ways and all that fancy stuff were designed for racers, not backyard bashers.

Re: Runner Yokomo Build

Posted: Thu Mar 03, 2011 8:52 am
by slapshot1979
OK, maybe reverse was the wrong word, how do you brake,slowdown.

Re: Runner Yokomo Build

Posted: Thu Mar 03, 2011 8:57 am
by jwscab
as far as I can tell from your pics, the rear sprocket is still hard attached to the robinson gears, and the one way bearing rides on the mid-shaft. This means that no matter what, the rear wheels are driven in both directions from the motor. So even if the front wheels free-wheel during braking, the rear wheels should be braking as needed.

is that how the gears are built? the sprockets are fixed to the spur and don't spin independently right?

Re: Runner Yokomo Build

Posted: Thu Mar 03, 2011 8:58 am
by scr8p
the rear has nothing to do with the one-way, just not the front. you should still have brakes at the back.

Re: Runner Yokomo Build

Posted: Thu Mar 03, 2011 9:09 am
by slapshot1979
Sorry guys this seems to be a lack of info on my part, the spurs I refer too are the 3 white unmounted ones in a pic on page 2 I was told they are robinson.
What is mounted on the car now IS fixed and yes it would brake but is 2mm pitch and worn and I plan on running 3mm pitch gears, which these white spurs have a 3mm pulley attached

Re: Runner Yokomo Build

Posted: Thu Mar 03, 2011 9:14 am
by slapshot1979
Yes JWSCAB the spur and rear pulley are attached on all pictured.
Thats why I think on the 3 new ones pictured you would have no braking as the rear would freewheel with the spur on the internally mounted oneway.

Re: Runner Yokomo Build

Posted: Thu Mar 03, 2011 9:27 am
by RC10Eh
Just build the damn thing , how hard can it be ?















:lol:

Better you than be buddy , as i read and try and keep track i get dizzy and i have to sit down . I even saw twostick poking around this am , he had to sit down too . Great work dude ! Really !

Re: Runner Yokomo Build

Posted: Thu Mar 03, 2011 9:30 am
by slapshot1979
You stay out of this RC10 , your the one who got me into this mess :)



Thanks I needed a good laugh this morning

Re: Runner Yokomo Build

Posted: Thu Mar 03, 2011 9:33 am
by scr8p
the pulley is still mounted to the spur. the belt from the pulley goes back to the diff. the pinion on the motor turns the spur gear. the esc tells your motor to start and stop. no matter what, you will alway have brakes in the back because the one-way and center shaft (other than holding the spur gear) has nothing to do with the rear.

Re: Runner Yokomo Build

Posted: Thu Mar 03, 2011 9:42 am
by slapshot1979
OK now what if the main spur was mounted on a 1 way bearing how would that work.

Re: Runner Yokomo Build

Posted: Thu Mar 03, 2011 10:04 am
by slapshot1979
I just cant understand why you would want to unload both belts off throttle, the front for sure I can understand, but both belts dunno....
Here is a picture of a NIP on the bay right now. this assembly contains a oneway
Image

Re: Runner Yokomo Build

Posted: Thu Mar 03, 2011 10:19 am
by adam lancia
The shaft spins in the one way, there is a hard, constant connection between the spur gear/rear pulley and the rear diff. The spur doesn't freewheel.

Re: Runner Yokomo Build

Posted: Thu Mar 03, 2011 10:22 am
by jwscab
OK. I'll try ONE more time, but then that is it..... :shock:

the one way bearing doesn't DO ANYTHING to the rear wheels. it's simply a nice close tolerance hub to locate the gear on the mid shaft. It could be solid and not change how the rear wheels operate. forward, reverse, brake all work as you would expect BECAUSE the spur gear is fixed to the rear belt sprocket. This would be IDENTICAL to a 2wd car.

the one way allows the MIDSHAFT to freewheel, thus allowing the belt that drives the front wheels to freewheel, thus allowing the front wheels to freewheel.

so in normal operation accelerating, the front wheels drive forward, along with the rear wheels, and upon braking, or no acceleration, they freewheel just like a 2wd car's front wheels. So you get characteristics of both.

if you put one of the gears on the car, and move the car and spur around by hand, you will see what we are talking about.