Often what is advertised on the box is not 100% true/easy to achieve. That top speed may have been measured going downhill or with strong tailwinds. Traxxas will do anything to get that high mph on the box so that it can advertise to the people who are new to the hobby. It's all in the marketing of the product. So yes the slash 4x4 may be able to go 35mph out of the box but i guarantee that it will not be easy for you to achieve
ive had my 4x4 slash up to 73 MPH with a 3s 8000 mah lipo 13.5v
Well I think I found out what the problem was. Apparently I was not charging the battery at a high enough amp setting. I set my 4500mah to charge at 5 amps and took it out for a run and gps hit 34.5 MPH and when I installed the speed pinion i hit 41.7 MPH. This is more to my liking. So now I will charge as high as I can. The only thing I will do now is recharge my stock 3000 mah batteries at 5 amps to see if I get any faster. On the box it says to use at least 4000 mah battery to achieve those speeds.
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