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I apologize up front, this may come across as a rant, but I must own stock in spur gears with all that I have chewed up over the years.

Why, on the RC10 motor plate is the bottom hole fixed and the top hole straight? It is near impossible to properly set and KEEP gear mesh without putting something into a bind. Most times, it ends up in the motor tightening or loosening (usually the latter) and next thing you know, stripped spur.

I would like to hear your 'fixes' for this abomination of geometry, so that we can share with everyone and potentially save the life of a few innocent spur gears.



My Fix:

I have usually made the lower hole 'sloppy', adjusted my gear mesh, leaving the lower screw loose so it has wiggle room. Once my mesh it set, then I tighten the lower screw. It allows the 2 motor mount screws to not get into such a bind that they eventually move the motor and mess up the gear mesh - ending the life of the spur and giving you a DNF!

Hi JK Racing,

Don't make the bottom hole sloppy, that is your pivot point.

I put the bottom screw in reasonably tight, tight enough but so I can still pivot the motor,

Take notice when the top hole in the motor starts to disappear in the slot and mark the point with a

texta, remove the motor then use a dremel to grind that spot in the slot.

Put the motor back in and find where the motor hole starts to disappear again and mark and file

or dremel again.

Put the motor plate in the vice with soft jaws, take your time as the dremel can easily get out

of control, I have filed the slot with a needle type file.

I try to take my time which means putting the motor back in a couple of times so only to make the

slot just wide enough.

I hope this makes sense?

Do you use thin paper between the pinion and spur to set the gap, you should just be able to rock

the teeth of the pinion in the spur.

Cheers, Dave.

Dave, thanks for the advice, my point for this discussion is looking for how each of us has overcome the lack of arc in the upper slot on the AE motor plate.

Sounds like you actually take the time and grind your slot into an arc. Sounds like a solid plan, and like you said, take your time and do it slowly.

Thanks for the input.

No problems,

Cheers, Dave.

i never understood why ae made that a hole instead of a slot.
i have tried both, slotting it and just opening up a bit.
i use washers either way.

yeah, I think a little bit of filing on the slot to make it more of an arc, plus a good heavy washer should give you everything you need.

Your'e right guys, a 3mm washer on both bolts is the go.

Cheers, Dave.

I toasted a spur gear each round at the VONATS with my rere 6 gear. I will try and open up the slot. What motor washers do you guys recommend?

That straight slot raises my blood pressure every time I look it, and every time a spur gear gets toasted. Hell, I even made the slot an arc on my home-made motor plate for my nTC3 e-conversion. If I can do it with a hand drill and some minature files I don't know what AE's excuse is...

I use the JConcepts motor plate with the curved slot, so I can't be of help there.

The washers I use are mil-spec from McMaster - PN 98032A429. I use them on all my RC cars.






This setup held my motor in place for an entire race day a week ago with zero issues.

I made the arc with a small file and also got the JConcepts motor plate. I like the JConcepts one better so I just used that one.

Hi Guys,

3mm washers to suit the 3mm screws that go into the motor.

With the slot mod and using thin paper to set the pinion to spur clearance, I haven't stripped a spur in

years.

Cheers, Dave.

I like these a lot. http://www.lunsfordracing.com/mm5/merchant.mvc?Screen=PROD&Store_Code=LUNS&Product_Code=7931&Category_Code=MOTOR

you could slot the bottom hole parallel to the top one allowing the motor to slide vs pivot. kyosho optima mid is done that way and it is a snap to set mesh. Washers help keep the screw head from creeping and protect the motor plate from getting marred and wallowed out around holes.

I was using the #4 aluminum washers I had left over and thought they were the issue. What about the spacing of the press fit pinion on the diff tube. Is there suck a thing as pushed on too far?