Losi motor / pinion-spur upgrade
 

I got me a Losi xxx-s...and i want to run it at a stock class race at the local r/c shop. The car comes with a 19 turn trinity, but i want to drop in a stock Trinity CO27. With that being said, i am at a lost as far as figuring out my internal drive. I know the car is stock with a 88 tooth, 48-pitch spur gear. Internal ratio is 1.83 as well. Now the book i got here says for a stock motor to run a recommended Pinion - 26 Spur - 88. Does that sound about right? I am new to touring car gearing, and i am hoping i can get an idea so i can set something up in the car that will give me better corner speed and more punch on the straights. Thanks guys for the help!

p.s.....if that motor sucks, please tell me lol :lol: iam lookin for the best stock motor i can get my hands on, iam a need all the help i can get! :batman:

Update: Losi has some upgrades for my car i found. They make different spur gears, and the list is as follows
88T 48P Spur, 90T 48P Spur, 86T 48P Spur, 128T 64P Kevlar Spur, 128T 64P Spur, 108T 64P Spur, 118T 64P Spur.

So those are the options, but just don't know what each one will do for me, more acceleration, torque, top end, etc. thanks for any help!

For a Co27, around a 25t pinion will be a reasonable start for rubber tires on a medium to large indoor track... (I'm assuming INDOOR and RUBBER tires?)... 26 might be too "tall" for indoors...

Don't worry about playing with different spur sizes unless you just can't get the pinion you need... I don't think I've ever changed spur sizes on my XXX-S other than to replace a worn or damaged gear -- gearing is gearing -- only the ratio matters...

I've been racing my XXX-S's (yes I have more than one), and the car is a very "drivable" one -- maybe a bit heavy, but I run full graphite and I am able to compete with XRay's and Yokomo's, etc...

PS: The Co27 is a good motor -- don't get too hung up on brand. ALL the blue can Co27 based motors come from the same factory, they just get "tuned" by different people. Locally, the Co27's are THE motor of choice for sedans -- very good combination of torque and RPM... If you want a "tuned" motor, I actually prefer Putnam or EA Motorsports, but I normally tune my own since I have dyno and lathe, etc. Trinity "Pro" motors have upgraded springs and brushes, but I don't consider them to REALLY be "tuned", as they are factory built in mass production. Putnam and EA Motorsports (and Brood, etc.) are true "tuners" -- they actually take the time to tune each motor. NOTE: You do pay more, for these motors, but you get what you pay for. On the other hand, there is nothing that says you can't get a good Trinity Pro motor, just that you safest bet is with a well known "tuner"...

I got ya, so what would be the affects of putting a spur on the car with more teeth than the stock 88? more accel? top end? and yes...carpet / rubber.

Assuming the pinion does NOT change, then going to a larger spur gear would result in less top speed, but faster accelleration. Similarly, going to a smaller spur gear would give more top speed, but reduced accelleration. Of course, small changes (like from an 88 to a 90) can be so small as to be hard to notice...

Does that help...?

i got ya. The club i race at has a rollout of about 27..and to obtain that, i have to keep my pin at 22, and spur at 88, that gives me a perfect 27. After i get a nice stock motor, i think it will be faster as well, oh yea and some match packs....