SCX10II Kit Trans Issues...

[JSterrett]

So... I recently managed to find an SCX10 II kit. Just got it finished up, and I'm experiencing some drag/binding in the transmission. Every few revolutions of the spur, there's noticeable drag, you can hear it slow down the motor briefly as it passes whatever area is binding. When assembling the trans the first time, it was really rough and there was a ton of binding, but that was resolved by flipping one of the gears inside...

It's definitely in the transmission/transfer case, disconnected both axles and it was still there...

Anyone else have a similar issue and have a solution?

[chiefmasterbeast]

I just did the gear flip in my transmission and it solved the concern I was having. Some have said there is some extra flashing from the molding process that can screw with the transmission. Make sure all the bearing are rolling smooth. Hopefully your motor isn't going bad.

[88gmchog]

Mine was rough but smoothed out, but I did notice when I put it together the first time I over tightened things and it caused a binding issue.

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[Shawns303]

Did you check the wobble on the spur? It's bad enough to change the mesh throughout the rotation.

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[JSterrett]

I was able to get it resolved, the gear on the output shaft (of the transmission, not the transfer case) was still binding up in the shoulder of the input gear. I was able to put a small shim (.5mm) between the output gear and the forward bearing and it cleared right up. Smooth as butter now, lol.

They really need to work on their clearances....

[JSterrett]

Originally Posted by Shawns303

Did you check the wobble on the spur? It's bad enough to change the mesh throughout the rotation.

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Spur was fine (other than the in/out play these all seem to have without mods), but while I had it apart, I added another bearing to the input shaft just under the shoulder for the slipper. There's a pocket in the front of the trans that's perfect for a 2nd bearing, just makes assembly slightly more complicated....

So I now have 3 bearings on the input shaft, one in the back and 2 in the front.

[MattySlimz1987]

Heres a video of my maiden run kit version. Sounds like same exact issues.. Going to take it apart tommorow and try a few suggestions some of these other guys on here have mentioned.. sorry for the dark lighting, just couldnt wait until morning to see if I had the issue as well. When assembling my Ax2 trans, I did not check any forum or video or anything as what to look out for such as little peices of flash that may or may not be in the case...

Did yours end up being like this? Im gonna tear it apart in the am.

[JSterrett]

Originally Posted by MattySlimz1987

Heres a video of my maiden run kit version. Sounds like same exact issues.. Going to take it apart tommorow and try a few suggestions some of these other guys on here have mentioned.. sorry for the dark lighting, just couldnt wait until morning to see if I had the issue as well. When assembling my Ax2 trans, I did not check any forum or video or anything as what to look out for such as little peices of flash that may or may not be in the case...

Did yours end up being like this? Im gonna tear it apart in the am.

Couldn't turn the sound up too high, but I don't think so...

Mine was more smooth for a second or so then brief drag/lug. Hard to describe, probably should have taken some video...

[MattySlimz1987]

Originally Posted by JSterrett

Couldn't turn the sound up too high, but I don't think so...

Mine was more smooth for a second or so then brief drag/lug. Hard to describe, probably should have taken some video...

Thats kinda what I'm dealing with, if you watch towards then end of the video around 1:00 minute or so with your volume at a reasonable level it really gives you a good idea.

[MattySlimz1987]

So.. after trying the gear flip that could not have been it... if anybody had that wrong the first time, I'm surprised they even went forward with the rest of assembly its so bad. That top part is going to give the spur some play no matter what, which seems to be just fine as long as you get your preferred-perfect mesh


What it does NOT tell you is on the parts tree is that little shim on number 6 I believe it was, SHOULD be used.

Put that on between that orignal spacer and sand/cut it down just a very little bit. If you put that shim on with the existing spacer and do not trim it down just a little, your not going to be able to seal the case.
I put it in there, put a little more of the CowRc grease in there and the issue is gone. The free spool of it is a little tighter, but I like it that way as it will add to more of the drag brake affect. Do not over tighten it or it will not have any play and it will be too tight for you to even spin the gears by hand.
Hope this helps.