new to micros

[the mad1]

hi guys i have just got myself an rc18b and i got myself a orion vortex brushless 7500kv system but i am having some issues i was told its cogging but i havnt got a clue what to do about it can some one advise me what i can do to help this please

[frogger]

There really isn't that much you can do about cogging on a sensorless system. You need to make sure your battery delivers good power and that your transmitter throttle profile is linear. Also make sure that if your ESC can have it's firmware updated that it's running on the latest version.

Then you need to experiment a little. Brushless motors send pulses to only 2 of the wires and then looks for EMF feedback on the 3rd to try and determine motor state. It could be that you might be able to improve the motor's responses by moving the motor wire connectors on in series. For example, if it's currently connected like this:

Red White Black
Red White Black

then more all 3 of them forward 1 position like this:

Red White Black
Black Red White

And if that is no better then try:

Red White Black
White Black Red

You will never get rid of cogging on a sensorless system completely but the above might reduce it.

[rocketrob]

also if you're trying to run stock-style standard NiMH batteries, and haven't updated to LiPOs, that could be making it cog too.

[Timee80]

Try going down 1 tooth on the pinion. This could help mate

[the mad1]

cheers guys i am running 1400 nimh's at the moment the other problem i have is all the wires that come from the speedo to the motor are all black lol and there is no colour coding on the speedo either so i cant tell what wires are what lol
i will try and move them around and see if that helps

[rocketrob]

Originally Posted by the mad1

cheers guys i am running 1400 nimh's at the moment the other problem i have is all the wires that come from the speedo to the motor are all black lol and there is no colour coding on the speedo either so i cant tell what wires are what lol
i will try and move them around and see if that helps

Moving the order of the wires might help, could make it change direction too, but IMHO you'd be best served by stepping up to LiPO packs and ditching your NiMHs. That will make a huge difference in performance as well as getting rid of most cogging concerns.

[the mad1]

ok nice one buddy i will get some lipos very soon then i have also been offered a mamba max for it with a 9000kv motor so il have that at the end of the month hopefully

[rocketrob]

Originally Posted by the mad1

ok nice one buddy i will get some lipos very soon then i have also been offered a mamba max for it with a 9000kv motor so il have that at the end of the month hopefully

I have no idea why you'd want a 9000kv motor, but unless you're just making parking lot speed runs I think you would find it pretty much useless. The higher the kv rating, the greater the chance of cogging - too.

good luck

[the mad1]

Originally Posted by rocketrob

I have no idea why you'd want a 9000kv motor, but unless you're just making parking lot speed runs I think you would find it pretty much useless. The higher the kv rating, the greater the chance of cogging - too.

good luck

i dont really want the motor i just want the speed controller really il use my 7500kv vortex motor on it and its coming at a reasonable price so cant complain

[mk2kompressor]

ive just fitted the orion speedo in mine and its awesome, the soft start on the mamba speedo took too long to turn off

[the mad1]

thanks for all your help guys but after some thought i have decided to give up with rc in general thanks alot though

[mk2kompressor]

thats a shame
let us know how much you want for the rc18

[the mad1]

i have already sold it buddy unfortunately and all the spares i had for it aswell

[OneKiwi]

Thought Id hop on this one or I could start a new one

Im new and have just got a LRP Shark 18

Nice little car driving round the section etc. Haven't yet gotten to a track but intend to soon.

I got a few questions:

I have it with a 7.2v 1100mAh Ni-MH battery, now I see talk about lipo batterys are they better/ last longer/ more power?

Will the battery charger I have to charge the NI-MH work for them?

Where can I get another battery Ni-NM or Lipo with the connection I need? Its a jungle out there...

Tyres, the ones that were with it are worn down so I would like to get some more off road tyres/wheels. I also have a pair of slicks that are a little bigger.
Again where from?

I ask where from cos there is nothing that says buy LRP Shark 18 parts here, or this will fit your LRP....

Are there other makes/models like rc18b etc that have the same dimensions that their parts will fit mine?

[sldmodels]

Ok, lipos are better than nimhs as they generally have more power, requires less maintenance, are lighter, and you don't need as many sets so work out cheaper - make sure you familiarise yourself with any rules regarding lipos that your local club (or where-ever you want to race) has. Some, like mine, say they have to be on the BRCA list (of which, there are currently NO micro lipos on that list), others simply state they have to be hardcased, others go by the micro section rules, and other clubs are "rules, what's them?".

The two easiest ways to tell if your charger will do lipos, are 1. it'll say somewhere on the charger / instructions. 2. it's age. If in doubt, do a google search or ask here with the make and model of your charger.

Parts, the shark has lots of different names, as lots of companies do their own copies, and I say copies, as literally, that's what they tend to be. Without tooting my own horn, check on LRP's website for shop details, but better still for the UK, check out SMD's website (remember to support your local model shop kids!). Failing that, try the bay.

Depending on what your running and where will determine tyre choice, but most people are going for Schumacher Rally blocks in white and yellow at the mo', which mount on standard size 1/10th touring car wheels.

[peetbee]

Lipos are great, but they mustn't be discharged below 3v per cell so a 'cutoff' on your speed controller is receommended. In terms of connectors, the majority use 'deans' style connectors as they are the most reliable, could you describe the connectors your's currently has?

What's the make and model of the charger you have? Someone will be able to let you know what it's capable of.

Tyres, as SLD says the majority of people running Sharks in the UK (where are you?!) use touring car wheels (12mm hex) and schumacher rally blocks or some run foams. If you are just bashing then some hardwearing tyres would be better, you need to find out what works at your local club before buying some though! Also, you may need to check your gearing if you increase the diameter of the wheels/tyres.

For more information on the Shark (and the Blaze, Vendetta, MB4) check out www.uk-microrc.co.uk It is uk based so if you're not then the setups etc may not be so suitable.

Apologies if it's a lot of info, but have fun!!

[OneKiwi]

can never have too much info..
my chargerPro Peak EX from RC system same as the battery

connection


At the mo it will just be a little bashing but I have started doing my own off road track and will have a look at an onroad one just paint some lines make a few small jumps etc

Are there any guide lines for jumps for the 1/18 size how high how far apart etc just so I don't go out and make them too high/big for the car

Im going to have a look at the local hobby store tomorrow for tyres and in the weekend there are the nordic masters here in gothenburg, sweden

[sldmodels]

Don't think that charger will work with Lipos. A good all round charger is the Anmsann one (round about the £50 mark). Those connections are standard micro connections, and what you might find is that they will melt, as they're not very good at all.

As Peetbee has said, the most common micro connector is the deans connector, as most micro lipos are soft cased. The most common connections on hard-cased lipos, are corally bullets.

Jumps, surprising to me at least, is how high and how far micros can actually jump. One thing I would say, is make your jumps wide enough, and then just experiment with various other things. You can buy pre-maid jumps, but to be honest, pop down B&Q or where-ever, and knock something up yourself for a fraction of the price. The jump I made for Dudley's national last year cost me about £150 in total, but that was my first attempt at anything like that, and if I we're to do it again, I'd have a better idea of how to do it.