savage dust bunny

Hi everyone,

I've begun to decide on parts needed/wanted for my BL conversion and of course, now I need some help!

The actual thread can be found here and if you have the google translate plugin installed, you may even understand the Danish text...
http://rc-forum.dk/index.php/topic,3...2.html#msg3322

First of all, it's quite amazing seeing the stuff you guys are doing and has definitely been an inspiration - wild wicked and whacky Savages are out there, roaming the dirt and asfalt.

My (probably only the first) question is about using the mechanical brakes.

I want to keep the 3 speed tranny (I'll probably mod it using llkoolskillets guide). I was thinking that braking this beast using only the motor would shorten it's lifespan and instead use the mechanical brakes. I'm not interested in getting a center diff, why? Just because...money!

Initially I thought using a Y-cable to the brake servo and ESC would make it a simple mod, but then I can't use the motor to reverse because the brakes will be applied - yes, I WANT reverse

I then thought that I can either buy a new radio with a fully functional 3rd channel and use that for the brakes OR mod the current radio and install a potentiometer with a spring loaded wheel, for the brakes. Makes sense?

Actual question in 3 parts:
1. should I just use the motor braking power beacuse the motor will be just fine? http://www.aliexpress.com/store/prod...497281046.html
2. or is the radio mod a better idea?
3. any other suggestions?

Thanks guys.

sparky 25

From the start forget about the 3 speed,

Just install the hpi idle gear and that's the transmission sorted which will also do your brakes and reverse,

That motor you showed in your link is a little low on kv,

What motor mount are you planning on using?

Foxy

OK, lots to talk about here.

First of all, it has been shown on many occasions, that it is cheaper to sell a nitro savage and buy a brushless one, than try to convert.

Electric braking will not hurt the car in any way, however... Unless you have a clutch system (such as the 'elektriclutch' I think that's what its called, by Tekno RC), you cannot run mechanical brakes. If you run mechanical brakes, you cannot have reverse (not without significant trouble anyway)

The 3 speed tranny is just not needed for electric. 2 speeds and 3 speeds, contrary to popular belief are a method of increasing acceleration, not top speed. This is necessary with nitros, which don't develop much torque low down. The stock Savage motor will be most effective at 28,000ish rpm, whereas a 6S electric will be most effective at 0 rpm. Bear in mind your max rpm with the nitro was aroun 32k, with the brushless it will be 2200*22.2 (like around 45k rpm), so the car will already be a LOT faster on the same gears than the stock nitro. 6S on an 18t pinion with a normal single speed savage pinion/spur arrangement, will give you insane acceleration and about 60mph top speed, which is more than anyone could ever want on a monster truck.

That motor you selected will be a total powerhouse, though it will turn RPMslike a nitro, due to the lower kv. Still, you could always adda few more teeth to the pinion to compensate, I'd be tempted to trya 22t pinion with the 6 pole motor. Go for it. Though the castle 2200 1512s are also a good choice (the green castle ones dont fit in the stock flux motor mounts without dremeling, but the black HPI version called the Tork (exact same motor with a different outer housing), fits like a glove). And indeed, motor braking won't hurt anything.

savage dust bunny

Thanks guys

sparky 25 - I expect to use the silver LCG V2 motormount from Kershaw Designs

Foxy - the motor is already ordered as it was on sale for only USD53 incl shipping due to it being a version 1 and apprently version 2 is out/on the way.

Mechanical braking is a pain, yes, that's now understood []

Just to make sure I understand the issue about the tranny, are you recommending I don't use the gearbox, or only 2 gears or 3 gears? Or are you in effect saying I should perhaps look at a solution like this? http://kershawdesigns.com/Savage-DirectDriveV3.htm

It's difficult selling stuff via ebay from Denmark, I think people out there are just too mistrusting. Here in DK, electric is amazingly popular and less people want to buy nitros...hence the conversion, plus it's just a really great project [8D]

Cheers for the help so far

Foxy

Use the stock flux single speed transmission (you'll find it dirt cheap on ebay as a complete unit I would expect), with the HD Drive Gear (search for it, that's exactly what its called, it would be quicker for you to see it on google images than for me to describe it), for brushless power, this HD gear is absolutely NEEDED. Even on 4S that gear in its stock form will be chewed to bits in two runs, taking out the other gears when it goes.

savage dust bunny

Thx again, I guess following this guide is what you reckon I should do?

Sounds feasible so I also get to keep part of the original look, but judging from the price tag for the parts, I may just go for the KD center diff anyway

http://www.rccoh.com/rc.how-to/savag...version-2.html

Foxy

Center diffs make the Savage drive much better, but they aren't so 'Savage' afterwards either. Forget double backflips for example.

sparky 25

To convert the savage nitro gearbox to flux spec you'll need,

Savage flux idler gear set part number hpi 100905
And the hd drive gear foxy mentioned is hpi 102514

That motor you have chosen will put out huge amounts of power, but the 6 pole design kills run time,

I ran a 6 pole on my savage flux when I first converted mine,
but it was a handful and run times improved with the castle 2200kv motor,

To be completely honest, I tried converting my nitro savage buying just the bits to convert,

but in the end I sold off all my nitro parts from my savage and purchased the hpi savage flux conversion kit,

It comes with everything including HD Diffs,
stronger composite bulkheads,
HD dogbones and axles,
motor mounts,
flux chassis,
battery boxes,
44t steel spurgear, 20t pinion and 25t pinion for running 6s with
Flux idler gear and just about every nut, bolt and washer to convert the nitro savage to flux spec,

I'm pretty sure once I sold all the nitro parts from my savage that the flux conversion kit cost nearly nothing,

I just bought a 6 pole 2560kv motor and 150a esc,

And dremmeled the motor mounts to accept the larger motor,

Hpi savage flux conversion kit, hpi 102534

savage dust bunny

Hi guys,