brushless losi 8b
 

hi guys, i have done quite a bit of searching on converting a losi buggy and was wondering what your thoughts were on this setup:
mamba monster 2200kv combo
Rc-M motor plate
6s lipos (i was looking at the flightmax 5000mah 30C lipos???)

basically what i want to know is if this is any good for bashing. i won't be racing but want something that will be able to cope with a high voltage out of the box rather than upgrading the revo :whistle:

what sort of gearing would i need? i am after the longeset run time and about 40mph top speed maybe?

thanks for looking

richard

I have an 8B running on 6S, but I use it for track only. Your set-up seems fine for bashing but I am thinking 5S would probably be enough. I run 6S with my MMM and use a Neu 1512 2Y which is a 1400kv motor and that puts my RPM just below 35k. I geared it at 14/48 to get her to around 40 mph and stock out of the box is 13/48. That's why I think you should be at your goal speed with 5S. I only use Zippy's and Rhino packs for now as they have held up nicely. The flightmax are Zippy batts too so I think you will be happy with them. Hope that helps some.

I think that 6s on that motor is a bit much...put it this way, if it were my choice in motors, I'd go for a 1700 60 series medusa on 5s in a buggy....even lower kv for 6s and just gear up a bit to desired speeds

thanks for the replies
i always thought that the higher the voltage the better because it keeps the electrics cooler?
if i was to run 6s what sort KV motor should i use? will the 1700kv motor not be slightly over the 35K RPM figure?
how many runs have you had out of your zippy lipos? because my trakpowers packed up after about 60 :lol:

6s and a 1515 is way to much for a buggy - the weight of a 6s 5k pack is too much and will impact handling even if you find a way of getting a pack that size under the body.

You are better off with 4s 5k with the mmm and either the 2200 or the 2650. Either will work fine.

Agreed. a 1515 is definitely excessive for a buggy. And 6s 5000mah is going to be super heavy (nearly 1.5 pounds). You'll have the heaviest buggy on earth.

If for some reason you really want the 1515 2200kv motor I'd suggest running 5s 4000mah or something to keep weight down. The excessive motor will also cause unnecessary battery drainage resulting in unnecessarily short run times. What seems to be becoming the "standard" is a 1512/2D 2650kv motor on 4s 5000mah pack. That will give you overall acceptable weight and probably 22-23ish minutes of bashing run time (about 16-17 minutes of hard racing)

What you mentioned will work - but you could be notably lighter and more battery efficient with a slightly different setup.

acually the 1y in a buggy never even opens its eyes, you will barely ever break 40 amps with that motor on 4s, and really the 2650 will seem faster in the buggy because of the high kv

running higher voltage will keep the electronics cooler as long as you also run a lower kv motor or lower gearing

ok so 4s sounds good
i have a mamba max esc that i have been running on 4s for quite a while but i just need a motor. what motor would be best? and what sort of runtime would i be looking at with 5K lipos?
i have been looking into gearing also, i have a 16T pinion already but what others would be a good comprimise for speed and runtime?
sorry for all the questions but i want to get it right 1st time round :yipi:

For a motor you want to run a max RPM of around 35-40,000 RPM. On 4s (14.8v) that would be 2364kv. Personally I run a Neu 1512/2D which is 2650kv and on 4s is 39,220 RPM. A little on the high side but I run on a fairly large outdoor track. I also run 16/46 gearing which I believe puts me at about 42mph top speed. I might be off on that though.

I'd probably suggest the new castle creations 2650kv motor.

-Jeff

my buggy is coming tomorrow :yipi:
i will be using a mamba max esc and 9xl motor on 4s until i get a better esc and motor (once the revo has sold)
what pinion should i use? i have a 14T and 12T hardened RCM pinion and a novak 16T pinion (are the novak pinions ok to use on the metal spur?)

thanks richard

Nice!

I would start with the 14t pinion. Turn the timing down and punch control up on the ESC just to start off conservatively. If everything works well for the first few runs make whatever tweaks you want.

Yes the Novak pinions are fine with metal spur gears. Though if you decide to go plastic there's a new option from Losi - LOSA3560, LOSA3561 and LOSA3562. I've been running my plastic one for about a year. My motor came loose when I cased a jump last week and the teeth went a little flat. I was running the 46t kyosho. I just ordered the 45t Losi to replace it. I'll report after some use how it's doing.

-Jeff

it turned up today and wow is it quick :lol:
running the 14T pinion and the tyres are completly bald now after a tarmac run.
the motor got quite hot though :oops:
i see what you guys mean when you say loud :surprised:
also how did you mount the motor mount because it seems that the stock plastic ones are shorter than the alloy one?
i will get a few pictures up in a bit

thanks richard

here it is:
electrics:
spektrum 2.4ghz receiver
ace DS1015 high torque servo
9xl brushless motor
mamba max esc with brushless fan and BEC
2 ftx 7.4v 5000mah lipos
RC-monster heatsink

14/ 49 gearing (i think thats the stock amount of teeth on the spur gear?)
RC-monster motor mount
RC product designs battery tray and esc mount
proline mug shots on hong nor rims

it runs great, the motor is a little hot but the esc was pretty cool by the end
it makes quite a bit of noise however, with the metal on metal contact between the spur and pinion.

with the gearing as it is i reckon it must be hitting mid 30's which is ok for the motor and esc i am using
i will eventually probably get a Mamba monster esc but what motor would be good? i really don't know whether to go with 4s or 5s though. i am looking for a cool setup with quite a bit of runtime
http://i136.photobucket.com/albums/q.../losi8b001.jpg
http://i136.photobucket.com/albums/q.../losi8b007.jpg
http://i136.photobucket.com/albums/q.../losi8b009.jpg
http://i136.photobucket.com/albums/q.../losi8b010.jpg
what do you guys reckon ???
thanks richard

Yeah - that motor is going to run hot. There's pretty much nothing you can do about it. I mean - you can drop the timing down on the mamba max, gear down a little (but it seems low enough as it is), turn on some punch control.. but other than that - it's just gonna be a hot motor.

You should simply upgrade to the mamba monster 2650kv combo. That would be the way to go for 4s. If you end up going 5 or 6s you have other motor options that are either more expensive (neu, plett, etc) or less expensive and not as effecient (feigao, medusa, etc). Personally I would stick with 4S and run the 2650kv with the mamba monster.

Yes - the steel spur is crazy loud. The plastic one is a LOT quieter but still makes a racket. I like running plastic personally. Never had problems with them and they're MUCH quieter.

-Jeff