Trying to figure it out if pinion is bigger for every turn of pinion you go more teeth on spur how can that reduce wheel spin ?

Unfortunately there is no universal answer to the gear up/down effect, espeically with brushless. I find that to a point, most like some amount of load and if under-geared, they seem to lose power everywhere. Best bet, if you have some time, try a tooth up and down, even if you can only test from cold for 3 minutes it should give you an idea of where you'll wind up.

Also, try turning down your current limiter. Start around 65%. I have never run mine higher than 80% on 4s.

This is one of the VERY cool parts about running the current line of Tekin Speedo's is the data logging feature you don't have to guess and feel the changes. You can read data to see if you are undergeared or overgeared and then compare that to lap times and you can learn a lot.

Gearing...
I think of this in terms of a pushbike.....
Big front gear (spur) - Small wheel gear (pinion) = Less torque more top end
Small front gear - Big rear (wheel / pinion) = More torque

Hope this helps....

Is this Fr-Ctr-Rear, or visa-versa..?

Anytime we refer to diff fluids we state the front to rear .

Great.. Now I have to have one..

Thanks Casper. Thanks a lot!..

Kidding. That sounds very cool. I may really have to have one.

Does anyone know if the E parts like battery tray and receiver mount from the 3.0E rtr will directly bolt onto the 3.0 nitro chassis?

I'm not 100% sure, but I doubt it...

OK so I ran my Losi for like 10 packs now and have a problem.
The suspension is not free, when I move it by hand (push) it doesn't come back as it should. The rear especially. It was like that from the begining but I thought it needs a few runs to settle.
I think I read something in this thread about it but now I can't find this... and I still don't understand what should I do.

pinch the rod ends, check for bent hinge pins. Take a pair of pliers and pinch them near the turnbuckle to open them up a little

Thanks for the tip, works great!

Has anyone tried mounting the Proline lexan wing on the 3.0? If so, how did you build up the wing washers to make it fit tight?

Switched it up with the white wing n some new wheels/tires....
One bad a** buggy
I love this thing...

I used a spare piece of lexan. And then small o rings and she fits good. Couldn't. Notice one bit of difference compared to the stock wing. Except the stock wing will last way longer lol.