Help Needed - Tamiya Frog ReRe - Rear Wheels Amount of Free Spin?

[jjsparx 3]

I am nearly finished on my Frog build and am checking everything over before I add the ESC and battery for a quick indoor test.

Not sure what the technical term is, but the amount of free spin you should have in the rear wheels on the Frog has me questioning if I have assembled the gearbox correctly. I have chosen the "speed" gear ratio if this makes a difference.

So, if I hand spin the wheels (no power connected, motor in place), they have no free play in them - the wheels move in opposite directions as expected, but they don't spin. I am comparing the amount of free spin in my rear Hornet wheels, which if you spin them by hand, just keep spinning nicely on their own (no power, motor in place).

Is this correct? Free hand spin on Hornet wheels last at least 20 seconds, same force used to hand spin Frog wheels lasts not even 1 second, if at all.

Many thanks in advance.

[Hobbimaster 200]

The drive shaft angles do not allow for the diff to free spin. It should spin by hand as you have said, but it will not just keep spinning by itself unless you compress the rear arms so that the drive shafts are straight. This is all normal for the Frog.

[jjsparx 3]

Excellent - many thanks for the fast response! Just what I needed to hear - I've looked at so many assembly videos on YouTube to check and no one seemed to mention it. I guess if I hadn't done a Hornet the week before, I wouldn't have questioned it. I can now add some power and see if all is working.

[rwordenjr 1891]

10 minutes ago, jjsparx said:

Excellent - many thanks for the fast response! Just what I needed to hear - I've looked at so many assembly videos on YouTube to check and no one seemed to mention it. I guess if I hadn't done a Hornet the week before, I wouldn't have questioned it. I can now add some power and see if all is working.

never had a frog! what are the gear ratios besides speed?

[Hobbimaster 200]

7 minutes ago, jjsparx said:

Excellent - many thanks for the fast response! Just what I needed to hear - I've looked at so many assembly videos on YouTube to check and no one seemed to mention it. I guess if I hadn't done a Hornet the week before, I wouldn't have questioned it. I can now add some power and see if all is working.

I'm running a Tamiya Torque Tuned motor in mine, with standard gearing, stock Tamiya ESC. If your running the stock silver can motor with high speed gear set, you may be limited to smooth surfaces, there's a possibility of over heating the esc.....Just have to try it. Also, I highly recommend the Frog universal drive shaft set, it helps smooth out the rear drive train.

[jjsparx 3]

1 hour ago, rwordenjr said:

never had a frog! what are the gear ratios besides speed?

From the manual, it offers:

Standard: 7.3:1 - 50T x 18T
High Speed: 6.7:1 - 49T x 19T
Torque: 8.5:1 - 52T x 16T

Not sure what any of that means, but sounds cool.

[jjsparx 3]

1 hour ago, Hobbimaster said:

I highly recommend the Frog universal drive shaft set, it helps smooth out the rear drive train.

Thanks for the tip, I will have a look and see if it's worth an investment. I want to get used to it as close to stock as possible and then see how much money I can waste on tiny imperceptible improvements.