Spur gear problems

[alien13]

About a week ago, I snapped the rear pivot brace on my Speed NT, to replace it, I had to pull the gearbox, to pull the gearbox I had to pull the spur gear. When I put it back together, I checked the gear mesh by putting a piece of paper between the pinion and spur gear. First run I fried the spur, put a new one on yesterday, ran 1/4 tank before the teeth sheared. I'm getting another spur gear today, but before I put it on, I need to know why this is happening.

I did make one other change, and that was to putosi red tires on, which are super sticky compared to the stocks. Could that be the problem?

EDIT Everything is spinning straight like it should

 

[bmoney]

reply

if your mesh is good i would say to loosen the nut (spring) a littlebit, and someone esle might have a better idea or noledge

 

[Metalhead Matt]

Well, your new tires will add to the problem, but not cause it. Your mesh has to be as tight as possible, while still being able to spin freely. A slightly tight spot is common. Better to have a slightly tight spot or two than to be too lose. Spur gears are usually not perfect. You should be able to just barely wiggle the gears, all the way around. It sounds like your setting your mesh a bit too loose. Pics would be very helpful.

 

[alien13]

Well, your new tires will add to the problem, but not cause it. Your mesh has to be as tight as possible, while still being able to spin freely. A slightly tight spot is common. Better to have a slightly tight spot or two than to be too lose. Spur gears are usually not perfect. You should be able to just barely wiggle the gears, all the way around. It sounds like your setting your mesh a bit too loose. Pics would be very helpful.

Matt, I think you just like to look at pictures.
I'm going to my lhs after work, before I bring it in, I'll grab a pic or two and upload them later.

 

[alien13]

I'm pretty annoyed right now, because I'm almost positive I was just fed a load of crap.

Here's the pic:

The guy at the lhs told me that the black collar between the spring and the slipper plate is spinning. Now the black collar is sandwiched between the slipper plate, which can only spin with the shaft, and the nut, which can only spin with the shaft. That's what he's telling me, and maybe I'm the dumb one, but it doesn't add up to me.

Here's a pic of my gear mesh with the new gear on.

 

[Metalhead Matt]

Looks loose.

 

[alien13]

Looks loose.

You can tell that by looking at that pic? How do I know how tight to make it?

 

[Metalhead Matt]

Like I said, as tight as you can get it, while still having play. It should just barely wiggle all the way around the gear, with the exception of a slight-tight spot or too. I don't set mine by looking, but by feeling.

 

[alien13]

Ok, I'll crank it down then. I thought it didn't have to be that tight, since the factory setting was pretty loose

 

[Metalhead Matt]

Crank what down? I'm talking about your mesh. How close the gears are together.

 

[alien13]

Crank what down? I'm talking about your mesh. How close the gears are together.

Is that the reason the spur gear is stripping? And I thought you were talking about the slipper, not the mesh.

 

[Metalhead Matt]

Read post #3. Your slipper should be set to slip 1-2 feet when the throttle is pegged.

 

[Rolex]

Slip a piece of paper between the spur and the pinion, then press them tightly together while locking your adjustment down. Crank out the paper and you'll have the perfect mesh, every time.

 

[alien13]

Ok, thanks. Seems I get alot more support here than I do in the Losi forum.

 

[Metalhead Matt]

Yeah, that's true for most other forums.

 

[Mickstix]

Also make sure you didnt crack or break a motor mount or something, that's letting your pinion (clutchbell) move when ya crack the throttle, and chew the spur.. Just give everything in the driveline a good look-see to make sure nothing is moving upon full throttle.. Good luck!

 

[2revo1maxx]

I almost looks like you have 2 different pitch gears there.

That clutch bell looks like the teeth are too blunt, the spur teeth look pointy.

 

[alien13]

I almost looks like you have 2 different pitch gears there.

That clutch bell looks like the teeth are too blunt, the spur teeth look pointy.

Yea, but that's factory. Though it wouldn't be the first flaw in the design of this pos.

 

[alien13]

I tightened it up, ran about two tanks through it, full stop to WoT and back, runs great! Now I need to do it all over again when I replace the clutch, since I have to start it in the air, and give it a good shove so it doesn't die right away.