1:18 Ruckus Differential Problems and Upgrades Discussion

I finally made it! Thanks everyone for inspiration, especially Mike81 for making this possible!
I put a caliper and the ball diff in my pocket and went to a local hobby store measuring some 1/10 scale dogbones. I was surprised that nearly every 1/10 dogbone they sell had the right ball/pin size, so i got the cheapest made from metal.
https://www.conrad.de/de/reely-10465-ersatzteil-zentrale-kardanwelle-1365357.html

So here is what i did:

Tools needed:
IMAG2583.jpg
- Installed 3 Racing Ball Diff for Mini Inferno or equivalent like Mike81 did.
- Dremel with cutting disc (or a metal saw and a rasp)
- 5mm dia. shrink tube (or other centering helper depending on shaft dia.)
- Epoxy glue
- 1 Dogbone (ball dia. 6mm, pin dia. 2mm, shaft dia. <=4mm)
- Some 4x5x0.5mm shims
- Caliper for exact length adjustment during gluing may help

IMAG2579.jpg
1. Switch the outer telescopic axle part from diff-side to hub-side like Mike81 did.
2. Cut the dogbone in half. Mine had 74mm length (pin2pin) which made 2 exact fitting bones.
3. Flatten out the center part of the shaft between the shrink tube on opposite sides like in the picture. Dont flatten where the centering shrink tube parts rest.
4. Slide 2 small rings of shrink tube over the shaft like in the picture. This is for a 3.3mm shaft. It may vary for your dogbone. Target dia. is about 4mm since this gives a snug fit in the telescopic part of the axle. This makes centering and adjusting length easy.
5. Epoxy the dogbone into the outer telescopic part of the original diffs outdrive. Pay attention that there is no air left so the whole axle is filled with expoy.
Target length of the assembly should be 42mm measured like in the next picture. Be sure to measure your ideal length before you glue it in since my bone got a flat head so you probably need a bit more or less length.
IMAG2584.jpg
6. Install the axle and put some 4x5mm shims between the outer hub bearing and the little wheel pin to remove the in/out play. This is important for maintaining the right ball position in the diffs outdrive.

DONE - F.Yeah! :)

Btw: i put Losi Mini 8ight Wheels on, which fit perfectly. They are nicely soft, a little bigger, provide excellent traction and look damn cool. Now my Roost looks and feels like a real Buggy. It feels rock solid and very responsive. Soon i will change the front diff too but first i will beat the hell out of it now. Hmm.. lets have a look for a nice brushless system...
 
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Awesome man. Glad you got your parts and it went together well. Careful shimming the hubs, if you get it too tight the weak brushed motor will melt in minutes. And if/when you go brushless make sure your slipper is on the loose side. Mine was tightened fully and I let my son drive because his amp esc melted. He pinned the ruckus under a log and before I could yell "no wait" he floored the throttle and I heard the loud bvvvvvvvt of the gear stripping...:(
 
First thanks for this great thread.
Reading this thread and trying out some, i want to let you know my solution for the diff problem.
I took the following parts and all things fits:
  • 3racing Ball diff 3R-MIF-048/BU
  • Bearings for diff taken from the original
  • HPI A557 wheel Axles
  • Bearing for the wheel axles 5x8x2.5 mm
  • Traxxas 1985 fiber washers 5x8x0.5 mm , it fits now the original width of the 4x8x3 mm bearing
  • Original 7x11x3 mm bearing
  • Tube 5x7 from OBI (DIY market) used as spacer between axle and original 7x11x3 bearing
  • Dogbone from ZD racing 1/16 partnumber KR646040 or 646040 or ZDR-6040 or ZD-6040
The part number depends on your country but ends always with 6040. This dogbone fits perfect with the axle and the 3racing diff, no additional work is needed

You also need some new wheel nut M4 and 12mm wheel hex, which fits the 5 mm diameter of the HPI axle.

best,
Guido
 
Gidien said:
First thanks for this great thread.
Reading this thread and trying out some, i want to let you know my solution for the diff problem.
I took the following parts and all things fits:
  • 3racing Ball diff 3R-MIF-048/BU
  • Bearings for diff taken from the original
  • HPI A557 wheel Axles
  • Bearing for the wheel axles 5x8x2.5 mm
  • Traxxas 1985 fiber washers 5x8x0.5 mm , it fits now the original width of the 4x8x3 mm bearing
  • Original 7x11x3 mm bearing
  • Tube 5x7 from OBI (DIY market) used as spacer between axle and original 7x11x3 bearing
  • Dogbone from ZD racing 1/16 partnumber KR646040 or 646040 or ZDR-6040 or ZD-6040
The part number depends on your country but ends always with 6040. This dogbone fits perfect with the axle and the 3racing diff, no additional work is needed

You also need some new wheel nut M4 and 12mm wheel hex, which fits the 5 mm diameter of the HPI axle.

best,
Guido
Click to expand...

Thanks for the parts list. Any chance you could post up a new thread with how you did it and pictures?
 
I will start a new thread in the next few days with a log of my custom build from my son's 1/18 ruckus. He is four years old and liked to drive the car very hard. "No crash , no fun". Hey said: "If I make it broken, then you can fix it yet?" and i answered "Yes i can" (hopefully). We will see how strong the rebuild of the car will be.

Sorry if my english is not quite right. I will do my best.
 
Gidien said:
I will start a new thread in the next few days with a log of my custom build from my son's 1/18 ruckus. He is four years old and liked to drive the car very hard. "No crash , no fun". Hey said: "If I make it broken, then you can fix it yet?" and i answered "Yes i can" (hopefully). We will see how strong the rebuild of the car will be.

Sorry if my english is not quite right. I will do my best.
Click to expand...

You and I have a similar relationship with our sons. Good thing dad is so capable huh? :D

Your English is just fine.
 
Gidien said:
I will start a new thread in the next few days with a log of my custom build from my son's 1/18 ruckus. He is four years old and liked to drive the car very hard. "No crash , no fun". Hey said: "If I make it broken, then you can fix it yet?" and i answered "Yes i can" (hopefully). We will see how strong the rebuild of the car will be.

Sorry if my english is not quite right. I will do my best.
Click to expand...

Glad to see more options to fix the truck are helping get people back on the road. Thanks for posting what worked for you. And feel free to post your diff upgrade pics here too. The more info the better to help people get their trucks fixed.
 
Yesterday i finished the rebuild and my son was so happy to see this little car. It is now a Monster SCT and no longer a ruckus. Self painted dromida body, medialpro tires and some other things.


IMG_20160608_195637_HDR.jpg

It was time to have a test drive after the complete rebuild. But i had only fun for 20 minutes. After 20 minutes on the street (no offroad) i heard some unwanted noise. My hope was that i forgot to fix the screw of the motor and the noise came from the main gear. I was surprised, it was not the main gear , pinion, ball diff, dogbone, axle or any other parts which i have raplaced. It was the original plastic gear of the diff out towwards to the drive shaft.

But a picture is better than words.

IMG_20160609_063433_HDR.jpg IMG_20160609_075536_HDR.jpg

No fun any more with this nice truck. My son will not be happy. "Oh poop".

Any ideas how to repair this, without buying a complete diff from ECX?

I'm so frustrated at the moment. It takes about 2 weeks to rebuild the car and now this happens.
 
:( aww that is what happened to mine about a month ago. Are you on the stock motor? My slipper was wrenched tight and with a brushless motor the truck got wedged under a log and my son was hard on the gas while it was stuck. I don't know of a way to fix that without a new diff but I do have an idea to be able to use a different gear there. I just haven't had time to mess with it.
 
Yes i'm still on stock motor. It's not planed to go brushless. It's fast enough for my son.

This time my luck was ,that i live in the near of the europe central support center of Horizon. Yesterday i was there, and i got a new gear for nothing. I think this will not happen twice, next time i have to pay.
 
Gidien said:
Yes i'm still on stock motor. It's not planed to go brushless. It's fast enough for my son.

This time my luck was ,that i live in the near of the europe central support center of Horizon. Yesterday i was there, and i got a new gear for nothing. I think this will not happen twice, next time i have to pay.
Click to expand...

Nice glad to hear that. I would set the slipper loose. And maybe try to find a way to shim that gear so it makes better contact with the ring gear.
 
Hi mikel81,

your modification looks very nice, I try to get the "3racing ball diffs for a kyosho mini inferno" but no way, may I ask you if you have a link or aparts number (currently I try to search for MIF-048)

thanks
 
I agree with slick. I no longer use the 3racing diff, because the destroyed my outdrive pinion. See my earlier post.

I switched to Vaterra Kalahari diffs. The are full metal and fits. The set also includes the drive shaft pinions. No more plastic in the diffs. Unfortunately you need to buy some additional parts to complete the diffs.

Part numbers are :
2x VTR212003 --- Diff house and pinions
1x VTR212010 --- Diff outdrives , not included in VTR212003
1x VTR215000 --- complete screw set for Vaterra Kalahari, includes the screws for the diff house.

Losi 1/14 Mini Desert Truck and Losi 1/14 Mini Rally using the same diffs.

I still use the HPI A557 wheel Axles. I also switch the dogbones to HPI H72069 6x47mm(from RS4 Sport 2). They fits on the wheel axles site, but need some work at the ball to fits the Vaterra outdrive. But this is not realy a problem.

My son run this setup now for 10 sessions with 2s Lipo with stock motor and it still looks good.
 
Well I ordered the parts and wow...the answer has been there all along. Thanks for posting the parts #'s I still can't believe I took the ruckus off the shelf. I took some quick pics just in case anyone else is in disbelief like I was. Full metal drivetrain, finally.

yBj38qB.jpg

47Kenvi.jpg


And I really tore up this last diff. I have never done this much damage.

xZTC2RG.jpg
 

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