CRT.5 build - would opinions on my setup choices

[MetalMan]

I was just out running my CRT.5 with React, Feigao 8L, Mamba Max, and 2s Lipo geared with a Robinson 14t pinion on the stock steel spur. No problems with glitching . 2.4ghz makes a nice difference from 75mhz.

[lincpimp]

Metal Man, what size tire are you using? With the stockers your crt.5 would be doing 22mph. I am guessing you are using a bigger tire?

[MetalMan]

It's at roughly 22mph with stock tires on 2s Lipo. That's why I bought a 3s Lipo today :). If I wanted to, I could throw an 18t pinion on it and get 40+mph.

[lincpimp]

Yeah, that sounds about right I had mine geared with a 20tooth pinion with the 10l on 3s and it did near 40. I did have jato wheels/tires on it thought. I have since converted to 4s and now use a 14t pinion, so much better that way.

[jnev]

lincpimp - any pictures of the 4s battery installed? If I remember correctly, people were having trouble fitting a 3s battery pack onto the truck. I can't imagine how a 4s pack would fit with so little room...

[lincpimp]

I am using a 4s 4000 maxamps pack. Basically took the emaxx chassis and cut out one battery tray. Made a plate to go across the top off the CD and stood the tray on its side. The stock hold down can be used with 3s but I used longer screws with 4s. Heres a few pics, works fine for me. I have the same setup in a LS10, slightly larger truck, but slightly lighter than the crt.5!? The pics show a 20 tooth pinion, that is what I ran with the 3s setup.

[jnev]

Very nice job on it. I really like that top plate. I hope you can make replica's since I'll want one similar in the future. Where do you get that antenna mount also? I have seen it before, but couldn't find it. Let me know.

Thanks.

[lincpimp]

The antenna mt is an integy mount, can't rmember the number but it came from tower hobbies! I am sure that I can replicate the top plate, and thread it to mount the tray. In fact I could do the whole thing with the tray too, if anyone wants one. Pm if interested for a price.

[VintageMA]

Originally Posted by lincpimp

The antenna mt is an integy mount, can't rmember the number but it came from tower hobbies! I am sure that I can replicate the top plate, and thread it to mount the tray. In fact I could do the whole thing with the tray too, if anyone wants one. Pm if interested for a price.

It's the same mount I am using too - very easy to install and convenient for anywhere on the chassis:

http://www2.towerhobbies.com/cgi-bin...+antenna+mount

[jnev]

Thanks for the link Vintage.

[BrianG]

I use that mount on a couple of vehicles and it works surprisingly well. Go figure: something that Integy actually makes well!

Of course, it would be difficult to poorly make something that simple unless you tried to...

[VintageMA]

Almost done!

Just got the React in the mail today. This radio is really cool.
Installed the transceiver in the buggy with the temperature sensor.
I've got the basics configured for the system and the difference is amazing.

The steering response with the digital servo is so smooth and instant. The motor response is smoother as well. I'll get the chance to run it outside tomorrow, but just running around the house there is no signs of glitching at all.

[VintageMA]

OMG - I love the React!!!!!

Took the buggy out to the park after work today. Ran the car pretty hard in grass through 2 of the 3S 5000 mAh packs and a 2S A123 pack.

Goodbye glitching - and goodbye heat. Seems the glitching was causing some pretty high current surges and heating everything up.

Running temp of the motor is now 110-120* and the ESC is warm to the touch. Batteries only just warm as well.

The range on this radio is really awesome, as is the feel driving with it. I am absolutely loving the telemetry - the heat sensor is just awesome. Hooked up the voltage sensor as well when i got home. I love the ability to change the alerting settings on the fly right from the menus.

I think I can consider this build complete.

[Thomas P]

I just ordred the Motormount, and some Mod1 pinions 12-13T..

Motor will be a Sintred 7.5r from Novak(will race this one indoor) ESC a GTB.

Now the LHS have some Serious outsale on Lipos here in Swe, so i was planning on 3600mah Lipo (2s) 20-30C do we think they can handle this?

info

3600 mAh - 20-30C - 2 celler - 7,4V
3600 mAh - 20-30C - 2 celler - 7,4V

7,4V

3600mAh

72-108A (20-30C)

2s2p

75x34x43 mm

190g

Kontakt: nej

Balanskontakt: ja - Typ APACHE/Polyquest

[VintageMA]

The Novak 7.5r is a small can motor rated at 340 watts output for 6 minutes. Because you are using a lower gearing I want to say that you might be okay, but I would have to digress to someone who has used this motor a bit more.

I think the lipos will be fine in this application, but I am concerned about the level of current draw for such a small motor with that high a kv rating. You will have to monitor the motor temp very closely for your first few runs to make sure it doesn't get too hot.

Personally I would prefer a lower kv motor on 3S lipo in a larger can size. If I were to go for a Novak for the CRT application (it's a much heavier 1/12 scale than most 1/10 scale on-roads) I would go in the direction of one of the HV motors myself - I like the torque that a larger motor can produce to get the car moving.