LRP X11 Brushless - TRF501x - pinion wobbles & mesh hard to get right!

[Fiddybux]

Right, this is a bit strange and I have actually fixed it, although it's not a perfect solution and quite sloppy.

Because on the 501x there is quite a distance between bulkheads, the pinion needs to be right on the tip of the motor arms bevelled-edge in order for it to reach the spur.

If you put it right over, so that it is fully (not 3/4 or 1/2) in contact with the spur then when you tighten the pinion it moves off centre, and because it is not perfectly true it wobbles when the motor is running because it is offset from perfect centre. This causes it to mesh perfectly for part of the radius of the pinion and to either be very tight or barely in contact with the spur for the rest of the rotation. This equals scary noises and probably a wrecked spur in the end (and undue motor stresses).

The only way to get the pinion to sit true is to set it back slightly at about 2/3 on the spur gear, but this is also problematic because too far back and it grinds on the belt - too far forward and were back in wobbly land! This is a very very fine line for me and takes ages to get right.

I'm using Losi pinions for this, size 16, because it's all I have. Size 15 does the same, as does 17, because they're right on the end of the bevelled edge on the motor arm and so aren't as tight a fit as they could be (if you slide the pinion back it feels physically tighter and more secure than on the end).

Does anyone have the same problem and is there a known solution, like maybe some different pinions? Are Tamiya or another make of spurs longer / different and solve this problem??

The problem would be solved if the X11 bevelled-edge motor arm was longer, or the spur gear was set closer to the motor, but it isn't and can't be, so that's a dead end I suppose (unless someone knows otherwise).

I'm running the 87T associated spur and not the stock 96T....although I'm pretty sure there would be little difference...unless the 96T spur is thicker.

I have considered grinding the bulkhead down to allow the motor to be closer to the spur, but this seems a bit extreme and a lot of work.

Any ideas, comments, questions welcome.

Thanks.

[Doomanic]

Sounds like you need some Long Boss Pinions.
Try RWRacing.

[veecee]

I've found this on my brushed motors running with Robinson pinions. So I don't run a full mesh. I would think the Tamiya pinions (there's one included with the kit) are ok but I've never tried it because it is undergeared for what I'm running. I'm sure there are pinions out there that would solve your problem.

BTW, post this in the Tamiya area and you might get a better response. It will also be handy for other 501X owners in future.

[TRF_Tastic]

Well, you are the first I've heard of running an 81t spur. I think that you will find most guys are running with an 87t. If you run the larger spurs you will take the pinion/spur mesh further away from the belts eliminating this problem you have of the pinion touching the belt.

I run the stock tamiya pinions on the 501 and for the sizes that I dont have I use the RW long boss pinions, I have never had any troubles with these on either brushed or brushless motors.

[gramey]

This going to sound really stupid but I bought my son a Nosram Storm 6.5 brushless and at the same time I bought myself the LRP X11 6.5 as my LHS didn't have two of the Nosram's.
No problem I thought, same motor different wrapper, until I came to use it and found the motor shaft on the LRP is shorter than on the Nosram motor. I had to buy the long boss pinions to get a good mesh when using it in my Predator, although I've now moved to a Cyclone D4 and don't have the same problem with that.

[jimmy]

the 81t is very small. I am not sure how you are rubbing the belt - I use RW pinions 15/16t with the 87 AE spur (which is thicker than the 96t kit spur) and the only time I had a problem with meshing was with my LRP motor which was faulty (the motor shaft actually moved inside the can)

I currently use a 5.5 Nosram X11 brushless motor and have no problem, the motor shaft is long enough to get a good fit with the pinion. I've never had a need to use a long boss pinion but I can see that some people might need to as not all motors are the same - but the long boss might be the solution.

[mobilow]

I ve the same problem, I have a long pinion 17T and at the end its totally polished from the front belt. I tryed to install a 16T one the last weekend but the screw was a little bit to long, and will hurt the belt so cause having no time to search for a shorter screw i leave the old ling one. But its horrible to change it cause you have to reinstall the motor.

[Fiddybux]

Originally Posted by gramey

This going to sound really stupid but I bought my son a Nosram Storm 6.5 brushless and at the same time I bought myself the LRP X11 6.5 as my LHS didn't have two of the Nosram's.
No problem I thought, same motor different wrapper, until I came to use it and found the motor shaft on the LRP is shorter than on the Nosram motor. I had to buy the long boss pinions to get a good mesh when using it in my Predator, although I've now moved to a Cyclone D4 and don't have the same problem with that.

This is very interesting that the LRP X11 rotor is physically shorter than the Nosram. This explains everything! But why?

I've bought a few more pinions now...the Long Boss will certainly do the job, but if you get it just right the Tamiya stock ones work well...but it's tricky.

P.S. You're all right...I said 81T and it was a mistake...I actually meant 87T and I have corrected this now.

[jimmy]

The LRP X11 is different to the Nosram Storm - which is the older X9 design.. Not to be confused with the Nosram Storm EVOLUTION which is the newer X11 design.

[_sleigh_]

Also not to be confused with the NOSRAM DRAGON brushless motors, which are the pressed can version, released earlier last month. They come in 9.5t, 10.5t, 13.5t & 15.5t versions.