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I'm putting together a Trailfinder2 with a Castle SCT Sidewinder 3800KV with a 14T pinion and a Futaba 4PL.

First, this is my first brushless system. When I start to pull on the trigger, the motor goes from not turning to lots of RPM's (IDK, maybe 5000 - guessing from sound). There is variable speed from that point to max but not like "I can see the shaft turning" speed I get with brushed motors. You, know - pull the trigger and you hear the HF musical tones first then the motor turns. Is this how brushless are or do I have settings incorrect?

Have you adjusted the esc using the CastleLink. You can set initial power and max power and many other things with it. I have a 4600kv system in my daughters T4 and I have it so it will do about 5mph wot.

I don't have Castle link.

You have am unsuitable system for the Trailfinder, for a number of reasons.

First the motor is way too fast if you want to crawl slowly, you only need a 1000-1500kV motor so you have plenty of torque for low speed control. The 3800kv doesn't have the same amount of low speed torque to keep turning over at very slow speeds. Faster motors also have a higher minimum speed before they start turning, so you won't get a slow speed crawl from them.

Which leads on to the fact the Castle system is sensorless.This means there is no sensor in the motor to tell the ESC what position the rotor is in, so the ESC just sends power to the motor until the motor starts turning. This means trying to run the motor slow enough to see the driveshaft turning will mean the power will be switching between the correct poles to the incorrect poles in the motor, leading to the motor jerking back and forwards. This is known as cogging. This just how sensorless systems are. In a short course truck the system is designed for, under normal use it will never be running at slow speeds so being sensorless in those situations isn't a problem.

You can reprogram the ESC on a computer with the Castlelink to lower the speed and change the throttle curve. That's the cheap option as the Castlelink doesn't cost much and worth a try to see if it improves things.

Long term I would suggest a slower motor for that truck and ESC, maybe even a Holmes Hobbies outrunner. The Sidewinder is also one of the best ESCs to run a brushed motor in scalers. If you go for a full sensored system, you will notice a big improvement in low speed control with it.

Personally all my crawlers still use brushed with Mamba Max ESCs.

You can download it free from their site. I'm not sure if you still need a special plug or just a mini usb. It's been a long time since I've messed with any of mine and they are old anyway. they may have updated their escs.

THEYTOOKMYTHUMB wrote:You can download it free from their site. I'm not sure if you still need a special plug or just a mini usb. It's been a long time since I've messed with any of mine and they are old anyway. they may have updated their escs.

The Sidewinder needs the Castlelink adapter, it doesn't have the standard USB port the Mamba has.

Great, I knew I should have stayed away from mondern technology. Many on a RC Crawler forum recommended that setup, that's why I purchased it. So keep the ESC and use a brushed motor? 55T?

You also need the Castle Link to switch the esc to brushed mode. The plug is very cheap though. Probably find it for $5-10. Can you gear any lower for now? I'm not all that familiar with it.

esaresky75 wrote:Great, I knew I should have stayed away from mondern technology. Many on a RC Crawler forum recommended that setup, that's why I purchased it. So keep the ESC and use a brushed motor? 55T?

The problem isn't the modernness of technology, it's that you've chosen a setup that's not ideal for your application. You're on the right track though, a high-T brushed motor with lower kV rating would be better suited to a crawler. You can adjust some basic settings with the Castle ESC but to really play around with the throttle curve (commonly called "punch" these days), you'll need their proprietary interface cable (Castle Link). Most of the current crop of ESCs allow you to program those various settings with a program card; you just connect your ESC's throttle connector into the card instead of the receiver and with a button and a bunch of indicator LEDs, you can really customize all the various settings.

Purchased the Castle Link and a brushed motor, thanks.

Seems that you have decided on a course of action, but I'll pitch in my $0.02

Is this how brushless are or do I have settings incorrect?

As has been explained, brushless is no different from brushed in regards to how turn rating affects min/max RPM. Having said that, I have never even entertained a Castle system because they are notoriously jerky & coggy at low speed operation. They also like to eat capacitors.

For your application, a sensored 21.5T BL motor (1,500-1,900 KV) would be far better, coupled with any decent ESC. I've personally had very good luck with the Dynamite Fuze 3780 and Hobbywing Xerun ESCs on the budget end of sensored controllers ($50-$80).

If you want mega torque and aren't at all concerned with speed, you can even go with 30+ turn BL motors:

http://www.ebay.com/itm/1100kv-brushless-motor-RC-rock-crawler-2-2-1-10-1-8-Axial-AX10-WRAITH-XR10-EXO-/161187706218?pt=Radio_Control_Parts_Accessories&hash=item258789356a

Remember, though; you will definitely want a sensored system for smooth low speed operation.

I was going to mention the same thing and going sensored is the way to go. I run all Novak crawler systems in mine.

If you wanted to stick with your castle brushless set up, you could get a GRU (Gear Reduction Unit) from RC4WD to tame it down but you went the brushed route so it should be more drivable and better for water runs.

I did pick-up a Castle Link cable kit and a RC4WD 35T motor, haven't had time to sit down with it. I'll try it with the Castle SCT ESC and see if it's what I was expecting. I don't have too much invested in the ESC combo, it was NIB $100 shipped from a ebay New York hobby shop. Kind of funny, the Castle Link cable also came from them, they were the lowest priced. Don't misunderstand what I said earlier, I knew unsensored BL motors were coggy. I just though with the gear reduction of a crawler, it wouldn't happen compared to say an RC10. It was my mistake for misreading on the crawler forums, they use just the SCT ESC.

I think you'll like the Castle link, this is the customizable throttle curve option. I "ramped up" the curve with only one of an unlimited number of points - just a quick example of what you can do with it, it's very cool stuff After messing with it, you may consider swapping the castle motor back in