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Old 07-27-2010, 12:06 PM
gazsouthgate gazsouthgate is offline
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Kyosho Landmax - Wheels rotating in opposite directions (***?!)

Hey all,

After 8 years, I am revisiting my Kyosho Landmax after I mothballed it when the wierdest problem occurred....please help!

Here is the background: Back in the day, I gave the car a strip down (not touching any preassembled components) to clean it. When I reassembled it (as I have done many times before) I found that when I started her up, the spur gear was making the rear wheels rotate in one direction, and the front wheels rotate in an opposite direction. So the car went nowhere! This was very strange, as I would (of course - duh) expect the wheels to turn in the same direction when the car is held off the ground.

I have disassembled the central diff 5-6 times in the past and rebuilt it successfully. I have never touched the front or rear diffs. (And I don't believe myself to be a total muppet with these cars!)

Can anyone explain what I have done wrong here - it is such an odd problem and I'm sure its something fundamental, and very obvious I am missing.

If you can help, or need more info, let me know. I am desperate to fix this thing!
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Old 07-27-2010, 12:26 PM
tadium54 tadium54 is offline
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i had the same problem with my e-maxx after installing new bulkheads. all you need to do is flip the diff casing 180 degrees. thatll fix the problem
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Old 07-27-2010, 12:49 PM
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terrible-t terrible-t is offline
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Mixed up the rear to front, switch the diff around.
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Old 07-27-2010, 02:35 PM
gazsouthgate gazsouthgate is offline
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Guys - thanks for the speedy replies. I'll take a look and report back.
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Old 07-28-2010, 08:54 AM
gazsouthgate gazsouthgate is offline
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Hey guys,

Following your advice I took a look at the diff casing, but I just can't seem to work it out. Here is what I did, and where I am now at:

- The Landmax diff casing only works one way around. If you try and flip it 180 degrees then the spur gear ends up in the wrong place, so that seems a no-go.

- Therefore, I took a closer look at the two bevel gears (and the gear in between them) INSIDE the diff. I flipped the bevel gears around, thinking that would have the same effect, but that didnt work (don't really see why it would?). The car still leaves the wheels rotating in opposite directions.

- As a test, I even tried flipping the whole diff casing around as you advise (even though the spur gear ends up in the wrong place) but still, the same problem.

SO - what I have found is this - AND THIS IS WHAT I DONT GET:

- If I roll the car, it freewheels perfectly well, with the front and rear driveshafts going in opposite directions as they should.

- HOWEVER, once you get the spur gear doing the work (with the wheels off the ground), the driveshafts rotate in the SAME direction, so the wheels go in Opposite directions.

- From looking very closely (and for literally hours) at the very simple(!) diff, what I can't see is how I would ensure when the spur gear turns, the driveshafts turn in opposite directions.

Guys - what am I missing? Happy to try and take pictures if that helps anyone and emailing them to you.

Gotta be honest - am desperate for help, this seems to simple, but I just can't make it work!
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Old 07-28-2010, 10:42 AM
Lille Buller Lille Buller is offline
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To me it sounds like the gears within the diff are too tight somehow so the diff dont rotate as freely as it should.
Too heavy grease or a grain of debrie or something locking it up.
I know zip about these cars tho..

I might be stating the obvies here, i donno..
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Old 07-28-2010, 02:21 PM
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Old_School_RC_1 Old_School_RC_1 is offline
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- If I roll the car, it freewheels perfectly well, with the front and rear driveshafts going in opposite directions as they should.

When you roll the car, the center driveshafts should be turning in the SAME direction, not opposite. Been doing this for 20 years, There is no car that I know of where the center shafts turn opposite. There is a differential in there that allows power transfer to proportion f/r as needed, but those center shafts should ALWAYS be spinning in the same direction.


- HOWEVER, once you get the spur gear doing the work (with the wheels off the ground), the driveshafts rotate in the SAME direction, so the wheels go in Opposite directions.


this is as it should be.

I believe you misread the above advice - the are telling you to flip either the front or rear diff, not the center....and they are correct. turning the center diff by hand spins true, but once you set it on the ground, power is now being applied by the wheels, and one of the f/r ring gears is on incorrectly causing the center shafts to go opposite. You have a center diff which is allowing this to happen, if it was a spool in the center, it wouldn't roll anywhere.

Forget the center diff, it's not your problem. Take a look at the front and rear diffs. When looking at the car from the top, you should see the front diff's ring gear on 1 side, and the rear diff's ring gear on the opposite side. If they are both on the right or both on the left, the axles will indeed spin in the opposite direction. You'll need to flip either the front or rear ring gear. One of them is on the wrong way. Turn the spur gear in the direction the motor would spin it and see which axle is going backwards - that's the one you need to flip.

Might even be easier than that: depending on the year, the landmax chassis should have dimples or recesses in it for the diffs to sit lower.The ring gear should be where the recess is. Check to see which diff is not installed correctly.

(you can see the gear dimple in the front between the 4 diff bulkhead screws..if you look real close, the rear is on the opposite side)


EDIT: Better pic


I know you've said you have not touched the f/r diffs, but I see no other answer. I've almost folded my T-maxx in 1/2 by putting the rear gear in the wrong way.

Check it out and let us know how you make out!

Last edited by Old_School_RC_1; 07-28-2010 at 02:34 PM.
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