cutting flatspot help.....
 

I've got a lehner Basic XL motor. Could you please tell me, is it really neccessary to cut a flatspot, the pinion seems to stick on the spindle quite well anyway. My problem is I don't have a dremel, I've tried to file the shaft, but because the lehner shafts are hardened steel it doesn't work.....any help would be welcome....

yes 99.9% of the time u need a flat spot go to the hardware store and get a grinding stone 4 a drill less than 4 bucks and start looking 4 a good price on a dremel

There is no need for the flat spot, I have had zero problems with the pinion coming loose thus far.

If the set screw is big enough to allow ample torque, the flat spot isn't necessary.

I have roughened up the shaft slightly with some sandpapers. Gonna use a bit of loctite (blue stuff), hopefully should be fine. Thanks for the help guys. I'll report on how it performs.

Don't glue the pinion on the shaft.. It can be a pita to get it off, when you dropped too much LT on it..

That's happened to me once already.....got a 16t pinion permenently fixed on one of my titans. I meant just glueing the grub screw to the pinion. Thanks for the help though

well, I tried numerous times, but it seemed no matter what I did the pinion gear kept coming loose! I'm using a robinson pinion (the one's mike sells) - anyone know why this is happening. Or should I just give in and make a flatspot. If so, is this the kind of thing I should be using? http://cgi.ebay.co.uk/ws/eBayISAPI.d...980323021&rd=1
The only thing I'm slightly concerned about is, brushless motors don't offer much resistance (basically none), so won't the motor spindle just spin around with the grinding stone...?

again thanks for your help guys! :)

Thats really odd, I haven't even used loctite, and I'm running robinson pinions also and they stick just fine, I haven't even noticed a difference between my brushed ones with flat spots. Are you using a hex tool to tighten that thing down or just the flimsy L looking tool?

The best way to put a flat spot on the shaft in my opinion is to take a pair of needel nose pliers put a peice of a rag around the shaft against the end of the can grip it with the pliers. Then take your dremal and make your flat spot. The flat spot only needs to be about 1/16 -1/8 wide and about half the lentgh of the shaft.

that's how I do it, too.

GREAT MINDS THINK A LIKE:eek:

:)

I stripped the set screw on a pinion cause I put a little too much muscle into it...I had to cut it off....with a Dremel. Dont know where I would be without my trusty Dremel...you dont have to get a Dremel brand either, you can get cheap rotary tools almost anywhere now...

stripped thread or a stripped head?

When I grind the shaft I cover the screw-holes and bearings with tape, to keep shavings out.
Putting the motor in a plastic-bag and sticking the shaft thru it works as well.

Remember: Metal-shavings plus Magnet equals Headache!

I bought this one. Pricing them, I was looking at Home Depot and they sell the flex shaft for $30 alone. The case it comes with is nice too.


Guide Gear Rotary Tool

Yeah, dremel (clones) can't imagine my life without them.. It enriches your life.. it's allmost as famous as 'googling'...

Those hints Dafni posted are very good to keep in mind indeed.

thanks for the help and tips guys. I brought an aluminium oxide griding wheel - meant for the dremel. Gonna use it in a drill (I don't have a dremel). Hopefully I'll be able to buy some kind of rotary hand tool at some point, they seem so useful. But after shedding out lots of money on my brushless system, I'm taking a bit of time out....;)

The drill will work fine. It will just take a little longer (less rpms).

cool, thanks. I'm definately gonna take into account dafni's suggestion, about covering bearings and holes.

just to report to you guys. Ground the shaft, works absolutely fine and holds the pinion nicely.

Just ran my bl maxx for the first time (2000XL/7018/18cells)...All I can say is wow!!! I was cruising along on asphalt in 2nd gear at about 10mph, jammed on the throttle (not all the way), and the truck just lit up. The front end rose off the ground, and the rear twisted round as the tires began to baloon, and I must have been doing over 30mph within a couple or seconds.

After a 5 run the batts were still cold (indicating they have hardly had to chuck out any current and still have loads of charge left), the 7018 was barely even warm, and the motor was fairly warm. From listening to the truck accelarating hard in 2nd gear, I think I can hear the slipper clutch slipping a bit. I'm running a stock slipper with 12pegs, but I'm going to tighten it all the way down - I don't do much jumping, so it shouldn't matter.

Thanks for all your help guys, and special thanks to mike for helping me out with choosing the right set-up and organising shipping direct from bk - cheers!! :D

YEAH! those large amount of cells do rock!!!

can you shoot a vid of it in action?

I will try to get a vid of it in action. Only problem is the only thing I can use to take vid's is a digital camera. The quality is very low, and there's no sound. I'll still try to take one, and post it up here.;)

I have never seen an XL2000 on 18 cells, so i am happy with a poor quality movie...

Just got back from a run. The temps outside are about 30degrees celcius....so hot. After no more than 4-5minutes running the motor was very very hot. I couldn't keep my hand on it for longer than 3 seconds. I noticed that one tooth had been stripped off the spur gear. Could this have caused the motor to overheat, or is it likely due to the high outdoor temps. I have it geared 16/72 on a 10lb-ish maxx, is this geared to high? Or is it quite normal for brushless motors to have much higher temps than brushed motors?

Gonna try again later with 15/72, and the outdoor temps should have dropped by then - 24degrees ish.

Thanks

You are most likely undergeared, actually. I would gear up a few teeth (try 20/72 or 22/72 even). On a hot day, the motor will run pretty warm, especially if you are accelerating hard often. Make sure you get some air flow over the motor as well to help keep things cool.

Sorry to drag this post up again. I got an IR temp gun today. My set-up is 2000xl/7018/18cells geared 18/72 in a 10 1/2 (ish) maxx.T he outside temp was about 80*F

After 15 minutes of some hard running in a parking lot (lots of high speed runs), the motor was 175*F, the batts were about 100*F and I don't know if the 7018 was even working, it felt so cool, about 90*F......:cool: . Mike, you reccomended looking at a 20,22/72 ratio, with this data, would you still reccomend it?

cheers

Great news, man. Glad to hear.

How can you fit an 18t pinion and a 72t spur? (no stock plate, I guess?)

I'm looking forward to try my sparkling brand new XL2400 on 14 cells.

Enter the dremel...... :D

Enjoy the lehner btw...;)

Yeah! able to shoot a vid of your monster in action?

With 18 cells, you have got plenty of power available for that motor!

yeh I will definately get round to it. I still havn't quite got the guts to let my finger drop all the way down and stay there. :p I need to lower the truck a little, at the moment it likes to go veering off course at about 3/4 throttle......

It simple screams for a g-maxx chassis!!

It's 2nd on the to do list, after cvd's (and maybe idlers...) I'd also like to get my hands on a pro-line suspension kit, it lowers the chassis quite a bit

175F after 15 minutes on a hot day is a pretty reasonable temp. A 20 or 22 pinion would be something to try and see what happens. Depending on the running conditions, it could cool things off or heat them up.

why so high?

20 or 22 tooth pinion is really high for that setup, correct?

20/72 or 22/72 is a little on the high side, depending on how/where it is driven. 18/72 should be a pretty happy place for the motor in most conditions.

what would you recommend for a e-maxx with a lehner xl3100, warrior 9920, 12 cells, 40 series bowties, with a 66 tooth spur?

i have a 14 on it now