RC Model Airplanes/Cars/Boats/traxxas slash


QUESTION: hi robin,
ive run nitro for years until i traded for a traxxas slash 4x4 bc theres a local indoor track. i currently have a 4200 & 8000 mah lipo battery that came w/ it. whats the difference bt the two? what do you recommend? i'm eager to race(although never raced before). any tips you could give me? and any info you could prepare for running electric would be appreciated. i'm infatuated w/ rc and want to hit the ground running (and i'm 44 years old-grow up right?)also, what are the most frequent problems w/ electric? eager to hear back and thanks for time

ANSWER: Hi there.
The numbers on the battery are a capacity rating in milliamp hours (mah). The bigger the number the longer your run times as a rule of thumb. You will also find a discharge rating ("c") and a voltage. The higher the "c" rating the more amps the battery can provide, and a higher voltage means more speed. The capacity rating divided by 1000, x the "c"  rating give the output amperage of the pack.
It would be a good idea to Google for a lipo battery care guide which you should be able to find on rcgroups.com
They can be dangerous if mishandled and easily damaged. A 4200mah pack is good for standard bashing and will give reasonable run times. 5000mah is a very common capacity.
As for racing tips, learn to lose because that's how you learn to win. Talk to local racers and get involved on forums online as they are a wealth of knowledge and tips.
All I'll say is get a good charger and a good few batteries. That way you can run your slash and charge other packs at the same time.
The slash 4x4 is a good platform with relatively few weaknesses but don't be afraid about breaking parts as they're readily available and not overpriced.
Hope this helps, do make sure to look up lipo battery care as it's important, rc forums are THE place to get answers and tips these days.

---------- FOLLOW-UP ----------

QUESTION: Hi again,
Would increasing the voltage from 7'4 to say 11 damage the truck? Also, are battery connections universal or do I need to buy traxxas only? Thanks for the previous response

Increasing the voltage to an 11.1v pack won't damage it but crashing will be easier as the truck will be going way way faster. A crash at the speeds you get running 11.1v will do some serious damage.

You can use whatever connectors you like. I recommend sticking with traxxas connectors however as they're decent quality and are readily available for purchase to solder to new batteries etc. For really high power setups you will want better connectors but for the moment you don't need to worry about that :)  

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Robin Bartlett


I Can answer most RC car and boat based questions, whether they be about engine tuning, electronics, making the right choice of equipment/car, mechanical issues, or how to set up a car or truck for different conditions. I can also answer basic boating questions and beginner to intermediate airplane questions.


I have been Driving RC cars since the age of 1. I built my first RC kit at the age of 4 with my father, and the hobby grew from there. I am also an amateur RC plane pilot. I am a seasoned Monster Truck racer, appearing regularly at shows in france and switzerland. I usually compete in 1/8 buggy classes, short course classes and MT classes. But im a basher at heart. I have also been boating for nearly 5 years, running Brushless offshore catamarans and deep-vees mainly, but at a beginner/intermediate level.

"Mini-Monster-Club-Romand" - local swiss forum "Centralemaxx" - large french forum, dedicated to Traxxas's Maxx series of cars

I give advice and tips on RCuniverse, BeatYourTruck, RC-Monster, and several others. I Have been a test driver for RCRacingCars magazine, test drove a "Tamiya TT-01D" in 2005 and a "Traxxas Rustler" in 2006.

I have had private schooling all of my life, currently taking IGCSE's. I have an "A+" in IGCSE French, an "A" in IGCSE English

Awards and Honors
I have won 6 short course races in the last year: Modified and Stock class. I have previously won club races in Electric TC stock class. I came second in a local club's 1/8 buggy class- won a Savage Flux from HPI Racing

Past/Present Clients
I run my own repair service, advertising in 3 of my local hobby shops and online on a small ads website. I usually get around five to six cars per week in the summer for repairs, and one or two during the winter

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