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Nickaford

Original Frog Transmission

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Hi all - first post here for me. I rebuilt my 1983 Frog over Christmas having found the spare parts required to do the repairs that have been needed for around 35 years!

The gearbox is original but I did “upgrade” the drive shafts years ago from the metal hex to some form of plastic hex. I gave the car its first run yesterday only to hear horrible grating noises when the diff operated - particularly on one wheel.

The diff is running nice and easy, and the resistance seems to change depending on the position of the rest suspension arms - if fully extended, the noise returns - if the driveshafts are horizontal it runs smooth.

I recall there being problems with the transmission when I first had the car - hence the different shafts. Looking at the spares, there is the dogbone assembly for the rere Frog which requires a pair of gearbox joints, driveshafts and wheel axles.

I have also seen the hop up option for the transmission but that’s £47 which is more than I want to spend.

Is the transmission from the rere compatible with the original frog?

Thanks in advance

Nick

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A common problem .You can restrict the drop of the arms by fitting a 3mm spacer into the damper body under the piston thus reducing the extended length . The noise is from the shaft grinding . You may also experience noise from the gearbox when it is running because of the alu side plates flexing and gears slipping  . You can buy aftermarket 'clamps' made by one of our club members which will cure that too . The original hex drives do work if they don't bottom out as described above . I only use original hex's as the the new dogbone setup tend to drop out - another common issue .

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I found and rebuilt my original Frog several years ago. Eventually, I replaced 95% of it with ReRe parts, as the old ones broke, were worn out, or otherwise needed replacement. It has lost all of it original-ness and I spent a ton of money.  In the end, I would have much happier if I had bought a ReRe Frog and built that, rather than rebuilding my original Frog.

I recommend cleaning and rebuilding your original, and then put it on a shelf. Buy a ReRe and run that.

Terry

 

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Thanks guys - I was 99% sure that it was the shafts and not the gearbox - although the clamps sound like a good idea - is there a link?

I’m not planning to run it too intensively - it was more of a dismantle and rebuild project but I would rather not risk damaging anything in the limited use that it will get.

Interesting that the rere shafts fall out - I think I have read that somewhere else - perhaps that’s the reason for the expensive hop up option!

if it is the shaft of the driveshaft catching, I might have a go at sanding it down a little near the ends so see if that increases the clearance - without weakening them too much

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The shaft ends grind within the drive cups not on the plastic arms. The dampers need spacing internally as I said before . I'll get a link to the clamps.

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Thanks Kev - I was wondering if the end of the shaft was catching on the hex shape of the hub. I’ll try the spacer in the damper as you suggested. Cheers for looking out the link for the clamp.

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Same thing I just went through with my Blackfoot, and the same solution: dialed in a bit of sag on the rear suspension and everything smoothed right out.

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1 hour ago, Nickaford said:

Thanks Kev - I was wondering if the end of the shaft was catching on the hex shape of the hub. I’ll try the spacer in the damper as you suggested. Cheers for looking out the link for the clamp.

No problem

Link to trans brace  :-

 

 

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I dig that pinion cover--very cool. I did something similar on mine, but not as clean.

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Kev - I’ve done some tinkering and have put spacers in the dampers as suggested - I didn’t have any 3mm spacers and only had 6mm so it’s riding a bit low at the moment but it’s not going to be doing any real off roading. I’ll look out for the smaller spacers. Thanks for the link for the clamp - I’ll have a look. 👍🏻

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27 minutes ago, Nickaford said:

Kev - I’ve done some tinkering and have put spacers in the dampers as suggested - I didn’t have any 3mm spacers and only had 6mm so it’s riding a bit low at the moment but it’s not going to be doing any real off roading. I’ll look out for the smaller spacers. Thanks for the link for the clamp - I’ll have a look. 👍🏻

You could cut the ( plastic ? ) spacer in two if it causes any grief

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1 hour ago, El Gecko said:

I dig that pinion cover--very cool. I did something similar on mine, but not as clean.

Thanks . I bought this from USA as an adjustable pinion kit but only used the cover - I can't claim this as my own work ;)

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4 minutes ago, KEV THE REV said:

You could cut the ( plastic ? ) spacer in two if it causes any grief

Thanks Kev - I actually used a brass tube - like those that go over the screw that holds the dampers in place. I’ll have a rummage to see if I have any plastic spacers 👍🏻

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Ok . Plastic would be better or some rubber tubing to spread any impact inside the damper tube

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I’ve found one side of the output shafts needs a washer behind it to correct the extra float.  I haven’t limited the shock movement on the models I’ve currently got.   The brace around the gearbox definitely helps though 👍 

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I helped design and heavily tested the ORV gearbox brace with a brushless combo and 3s LiPo and it holds up really well :)

@Xeostar did all the actual design work 

I’d defo recommend getting one of the braces just to protect the internals

there was some on eBay but they sell out quickly but ask @Xeostar and he will do a run no doubt 

also as has been said, the over extension of the trailing arms creates locking up and also increases the distance so can cause the dog bones to  pop out (ive painted mine day glow orange)

 

also have a look here 

 

 

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1 hour ago, Frog Jumper said:

Can the OG Frog dampers fit a spacer inside???

Yes , loads of room in there

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