gearing help

[tallyram]

i tightened it all the way, no difference. i think eveything is ok. on grass it doesn't get the same traction, just seemed like the slipper was loose. i guess the tires were breaking loose with less traction. thanks, carl.

[coolhandcountry]

You can take if off make sure the grease from bearing did not come out and get all over the plates. That will cause it to slip. Make sure you didn't shear the pin off in the plate to. While you got it apart you can see if it was slipping or not to.

[tallyram]

will try coolhand.

[tallyram]

everything looks ok to squee and myself. check my "burnt slipper pads" thread in brushless, it has a pic. thanks, tally.

[BrianG]

After running it for a while, feel the slipper plate. If it is slipping a bit, it will be quite hot (be careful not to burn yourself like I did once!).

As to the rc speed calculator: the speed calculations were made based on the various gearing (which IS correct BTW), motor kv, battery voltage, and tire diameter. Factors such as weight, rolling resistance, drag, real battery voltage, and actual kv can have a significant impact on the real-world result, especially at higher speeds.

For instance, in the RCM store, the Wanderer motors there are listed with loaded kv values. However, if your model is quite light and you are running at top speed, maybe the actual kv approaches the unloaded value instead? Or the actual kv value of your motor may be slightly higher than specified. The battery voltages listed are based on 1.2v for NiMH/NiCD, and 3.7v for Lithiums. NiMHs can be higher, like 1.3v under a light load, and Lithiums can be higher as well. This can also make a difference.

There are so many factors to take into consideration that it is difficult to come up with something very accurate. Even in my experience, my Revo seems to go faster than I calculated. But, I can't simply add a "fudge factor" to compensate because of the vastly different vehicles and it would be inaccurate at best. Unfortunately, I realized all this after I finished it.

[tallyram]

its still a good baseline. at least you'll be in the ballpark by using the calculator. a useful tool!

[BrianG]

Thanks! Glad you like it.

To get a baseline range, enter values like you have been. Then, enter optimistic values like unloaded motor kv and a battery voltage that uses 1.3v per cell (or 4v for Lithium) to get the maximum possible speed. Your real speed should be somewhere in between.

[tallyram]

thanks, i'll try it.

[squeeforever]

I found it pretty accurate for my 10XL in my Revo but not so with my XL3100. With my XL3100 it was doing over 50mph easy on 12 cells but the calculator said 32....20mph off is a big difference. Whereas, it said 42 for my 10XL which is about right. Why was it off so much on the Lehner motor but not the Feigao?