Need some advise for changing from brushed to brushless
 

Ok, so I know about the different types of brushed motors and esc's out there at the moment but when it comes to brushless I havent got a clue, at the moment im running a 15*3 brushed motor, I do want to change it to brushless, but no idea what the different types are, whats the difference between the number and stuff? what speed controller and lipo would I need for brushless motor, ive seen people talk about 8.5 motors but still no idea what the difference is between an 8.5 and 13.5

If anyone could shed any light on it I would be greatful, and also any suggestions for any cheapish/beginner brushless setups would be great

Very approximately - If you divide the brushed motor wind by 2 - you end up with about the same brushless.

IE 13 turn brushed is approximately a 6.5 brushless.

so a 8.5 is faster than a 13.5?

Yes the lower the number the more powerfull the motor is.

ezrun systems are good value for money from ebay. they usually come with a 8.5T and run well.

That's a bit too generalistic I think as a 6.5 is way quicker than a 13 IMHO, though lipo skews it slightly.

8.5 = 12 or 13 turn
7.5 = 11 turn
6.5 = 10 turn
5.5 = 8 or 9 turn

If you want something the same ish speed as the 13 I'd go with an 8.5.

A 10.5 I think is suppossed to be roughly equivilent of a 19t motor

i got a ezrun 9t in my losi xx and it flys:thumbsup: and i've had no probs with mine

Ginge

what esc would i need with that? and lipo?

it comes with the esc:thumbsup: have a look here http://cgi.ebay.co.uk/eZRun-V2-9T-43...4.c0.m14.l1262

its where mine came from

Ginge

are these BRCA legal

perhaps look in the second hand section and buy a recognised name (lrp/nosram/tekin/novak) then you will get a product that people will be able to help you with as they have more knowledge on those products.

motor wise dan has already said about and if you are running a 15x3 now then a 8.5 will be more than enough for you.

when considering lipos then look at the c rating and mha rating as well. the higher both of these numbers are then the more grunt your car will have. hence most people using a 7.5/6.5 motor in 2wd at a national level but then using monster lipos to get the horsepower they need. with the 8.5 motor perhaps go for a 25c rated 4000-5000 mha lipo so it remains smooth and easy to drive like your current package. motors again use the names mentioned above, they are used by a lot of racers so will be in good supply second hand if needed.

for lipos look at trackpower/orion/vampire (there are loads of makes available). ive tried to remain unbiased to what i feel is best as they are all much of a muchness. some warrentees are better than others on the speedos so make sure that what ever you buy has a good one ;)

Hmm ive now seen some brushless motors with a KV value (eg 8000kv) instead of a turn value? Whats the story with these?

If the motor is showing a Kv value it will be a sensorless motor (and as such needs to be used with a sensorless ESC) - the Castle Creations Mamba/Sidewinder are sensorless motors.

Sensorless tends to be cheaper but can suffer from cogging (stuttering) when starting off or at low speeds which is where the sensored ones are smooth.

so im guessing the higher the kv number the faster the motor?

Yep! The higher the Kv the faster the motor.

You can also find the Kv rating for sensored motors (the instruction booklet will list RPM/Volt or something similar).

kv's
 

the best sensorless to get is either a 5700kv or the 6000kv.
i used a mamba7700kv in my losi and totally destroyed my gear box.:thumbdown:
for me i've drawn the line with a 6000kv as i need reliability these days.
hope this helps. :thumbsup:

Cool, 1 more thing (for now), will a 7.5 or 8.5t be ok for my DF03 Dark Impact? or will it be too fast/slow?

Should be OK, but I'd recommend getting a slipper-clutch for it to save your drive-train from too much damage.

already got 1, it came with pretty much all the hop ups you can get, just need to find a new gear cover and a new shell for it

Will you be running it at the Bury Metro club?

The track there doesn't really need mega motors so something like an 8.5 in a Dark Impact is fine. The Ezruns are the best sensorless option - Mambas are great, but cost nearly as much as a sensored system so aren't worth it in my mind. The Ezrun 8.5 or even 5.5 if you feel bold are ideal for a DF03.
Come along one Sunday, theres a couple of us there can show you one in action....

I was planning on yeah, I have been down to watch you guys once but just for 5 mins. Once I get it changed to brushless ill bring it down cos i live just up the road from the goshen. Is it just sundays its open or are there any other days I can pop down, I often see a few kids riding over the track on their bikes when I walk my dog on the field there :confused:

I've tried various types of speedos and motors and would echo most of what has been said. If you intend to do regional or national events then you would need lipos and motors that are on the BRCA approved list. If just club racing then whatever you like.

Providing the drivetrain is up to it, ie you have a slipper clutch which you've said you have, something in the order of 6.5 sensored or 5500-6000kv sensorless would be about right. I have run mambas sensorless and LRP sphere sensored and would probably say the LRP just edges it for smoothness at the bottom end. I have had some cogging issues with the Mamba but got it all sorted with latest firmware. As has been previously suggested, trying to pick up a used speedo might be the best option as many upgrade regularly so there are lots available on here. THe LRP Sphere 80700 is last years model but is excellent, and there is Nosram one that is essentially a clone so I'm told (correct me if I'm wrong). The Losi sensored motors are around 50 quid and are excellent. As for Lipos well the cheapest way I believe is to buy them online from Hong Kong. The intellect branded ones (also cloned by others i believe) can be had for around 45 quid for a 3800 35C and should deliver the punch required. Other than that, make sure you use decent connectors (Deans or Corally type generally used by most).

Cheers

Chris Robinson

Wow, those intellect lipos aren't half bad. You don't happen to know what sort of size the 3800 packs are, do you? I'd like to put lead under the LiPO, so I guess many packs would be too big...

Just working out potential xmas gifts from the wife :D

We only race on Sundays, but the fence is low and the track is there all the time, so people play on it all week long. But there are no course markers when we aren't racing.

Hop along one sunday anyway - bring your car and we can advise. We can show you most of the options in action. New people are always welcome.....

They are slightly raised underneath so you could probably fit a slither of lead under. Not sure the exact dimensions, but you could find out I'm sure with a bit of research. If you go to the Bury club as hopefully I will this weekend then you can try them for size.

Chris

Thanks for the info - Im all the way down south in Southampton, so I definitely won't be able to make it to Bury, unfortunately..

From BRCA approved battery list for Intellect 3800 35C.

Length: 137.10 mm. Width: 46.08 mm. High: 21.23 mm. Wt. 236.2 g Has chassis location

It has dimensions of all approved lipos on there

Cheers

Chris

If it helps:

I was running a 13x2 on nickel batteries in my 501x and am now running a 8.5 brushless on lithium batteries in my 511... assuming the chassis' perform similarly (and they do) I can assure you that an 8.5 brushless is way faster than a 13x2 brushed!

I suspect 8.5 will be well sufficient for your Dark Impact, at least to start with. I have no idea how people use 6.5's on a small track… they obviously have skills that are way, way, way beyond mine lol, I'd just destroy my and every other vehicle if I tried that at the moment!

I'm also running the Intellect 4200 LiPo saddles and can confirm they fit into the 511 just fine, as a result I'd expect the lower capacity ones to present no problems fit wise.