what pinion/spur do all you people on 5.5s have, I think mine may be a bit high as it is not a lot faster than a 19t at the moment.

If you geared it the same as your 19 turn the 5.5 should be much faster. It probably needs gearing with a pinion roughly 3-4 teeth less than the 19, but this will slow it down rather than speed it up. I was running a 18/19 pinion with the standard spur on a 6.5L at the steam fair, the 5.5 would be pretty close to that.

Unless you have an absolutely tiny pinion, with almost any gearing it should be faster than a 19. So I think something may be wrong. There's not much to go wrong with a GTB though, perhaps the one touch setup? As you open the throttle do you get a full throttle indication from the lights on the gtb?

if you lift up the back end and spin the wheels the tyres will baloon, but it just can't seem to get the power on the ground. I am also having reciever problems which I didn't have with the 19, accelration is jerky and the transmiter range has suddenly gone down from the length of the track to about 2 metres

Novak recomend you don't spin up the motor without load, as the higher than normal speeds could potentaly cause the rotor to break apart, you would definatly know if this happend!

i think i run a 20 tooth pinion with either the 4.5 or the 6.5, running too small a pinion can cause overheating too, they don't seem to like being held at full speed for long.

you had problems with radio gear at the onroad meeting too, is it the same transmitter? might be worth checking the batterys are good, obviously, and also that the connection to the arial inside the unit is not corroded or broken.

check you've got a good connection into your reciver, try giving it a wiggle whist running the motor at low speed.

if you swap the reciver from one car to the other, check the ariel wire isn't broken inside the reciver, or along the length with a multi meter.

check all reciver wires are as far away from power cables, especialy the motor wires as this can cause interference.

i've just been helping dean wheeler with his new gtb, he was struggling changing the profile he'd selected and, rather than picking the profile he was going into the mode were you can change the parameters for that mode. connect up, and switch on tx, then speed control, hold the button for about 4 seconds whist the lights flash, leave go of the button and it'll blink a number of times to show what profiles selected, press the button till you get the one you need, probably no.2 wait a few seconds then switch off the speedcontrol to save the setting.

i'm using profile 2, when i'm at neutral i have one red light, at full forwards a green light, and full reverse/brakes an amber light, you might also have another light at neutral to indicate lipo cut off being on or off, as i don't have that on my older gtb. again i only had the trottle at full for a fraction so there wasn't time to get up to excessive speeds.

i though that most of the instructions were good for the gtb, but i couldn't find anything about what lights idicated what in the normal running mode, or how to leave the profile select without going into adjusting the profile


you did have charged batterys didn't you!

I run the 5.5. I think I run 86 spur and a 14 tooth pinion in the xxx. I found that on the tracks we set up outdoors for on and off road we have a small straight and top end was no that important. That said I can't atually go any bigger on the spur or smaller on the pinion with the kit I have. And the top end I have is enought I think, Tom and Glenn may not agree with that though.

Check the end point on the transmitter when you set the ESC up. I had fun where the thing had no real increment between on and off, and behaved like a switch. I ran with profile 1 for ages as I was used to having no reverse. I changed it recently to have reverse and I am still not used to it.

What are your cells like, Rick has a dodgy set of cells of mine and when I used them I was well down on power.

Does anything feel hot after a run? ESC, motor, Cells?

How is the slipper set up like? Is the diff tight?

no wonder it's not fast if you run out of range after 2 meters!!!!

Obviously check the transmitter batteries too. Really sounds like a radio / wiring problem now. I know my Novak HV will stutter when nearing the end of the it's range, so sounds like you may be struggling with the signal. I can't think of anything you could do to your GTB or car that would cause jerkyness, even weak batteries would likely just be slow, but smooth. So like Rick says, check the aerial and receiver wires, probably worth a look at the sensor harness too.

Just a thought, but did you order the whole system? Or get them separately, just that there is also a spread spectrum version of the GTB, it should say on it, which is only suited to 2.4Ghz radios and could behave something like you are describing with a normal radio.

the first thing I did was buy new batteries for my transmitter but it has had no effect. I did buy it as a system and I am using the same transmitter I used on sunday. receiver wires and speed control wires are as far away as they can be from each other slipper is set up as tight as it can be without bending the spring and I took out the gearbox the other day, gave it a good clean out and put it in a new housing, so it is really smooth and tight.

just an idea:
http://www.apexmodels.co.uk/product-sea ... s&id=17119

i'd suggest getting a better quality transmitter, even looking at second hand futaba or ko ones on the bay to me would be a better option. i take it you have checked it's not the spread spectrum one

Ok my turn now:

Check the connection between the transmitter aerial and where it connects inside, as this can break and dramaticly reduce radio distance.

Check the reciever wire for breaks and bare wires

Go through the GTB instructions setting everything as default and all the connections are correct

Try different crystals

Disconnect the servo and try it.

In terms of gearing I was running the 3.5R on the largest spur and a 14t pinion. But I would exect the gearing to run would be something along the lines of a 17/18t pinion. I try and gear my car to reach top speed by about 3/4 the way down the straight.

well if it is the spectrum one it's not obvious. theres nothing on the box or in the instructions.after following all your advice I have taken out on the street a few minutes ago. It is less jerky but it still will go out of range very quickly sometimes. A new problem is that it will get sudden spurts of power which I have no control over, so it goes straight into the hedge. It is now a bit faster aswell. I'm not sure why but it still seems slower than Paul's or Ste's. might just be because it's lower geared though.

PS I am still on 27mhz. would that affect it?

here's a link to a spread spectrum one

http://www.rceasy.com/wp-content/upload ... 4/1711.jpg

no, it hasn't got that written on the side

RESULT so go check your ariel on both tx and rx, and the connections to rx are good, try moving them about whilst running the motor slow, with the tx ariel down see if you get any funny results, there the easiest things to check

I'm sure it's a radio problem, don't even worry about the speed until you've got it driving smoothly.

Do the wire check. I've got a spare pistol 27Mhz radio / receiver from my Savage you can try, I'll bring it on Sunday.

If you're thinking of buying, like Rick said it would probably be worth holding out for a Futaba / KO.