RCCrawler Forums

Jay-Em · 12-05-2011, 04:14 PM

did some on-line digging, and the blackfoot is 1:14 geared. with a stock 27t silvercan, that might work. I doubt there is a spur/pinion combi with that ratio that'll fit the Wraith gear-box though..

For the Titan i'd keep it at 1:20. Mainly because a Wraith is about 300 grams heavier, and has 14cm wheels instead of 13cm. If my rough calculations are correct, 72/25 should get You 25 to 28 km/h, and You'll have some crawling ability left. Good bashing territory in my book. I am not sure if that combi fits though.

I am going to put my money where my mouth is, and i am going to get me a 72 spur and some 25 to 28 pinions tomorrow, just to see how close theory is to practice, and to ascertain how much of hot air my guesstimates contain..

Jay-Em · 12-07-2011, 09:54 AM

Tried, for shi7 & giggles, my 6.5t exceleron BL with 80/25 (1:25)

Wheelies on wet pavement [kit-tires are tha' bomb!], accelleration is Still rocket-like. I can make it jump a meter from mu' doormat. Weird sight. Praise the heavens for Jun-Fac punishers....
Didn't try measuring speed -it's raining cats&dogs overhere- will do that when it's dry again.

Eye-ing it, i'd say I must be pushing 40km/h, wind in the back.... Wow...

I guess I am right that the Wraith is seriously undergeared to get that cheap 20t behave as a semi-crawler motor.
Soo..there IS a reason Losi initially choose the exceleron-line for it's brushless line-up.

crazee horse · 12-07-2011, 10:43 AM

So your saying that the titan will be very happy bashing AND crawling on 25/72 ?
I've been getting a bit confused with all this ratio talk lol
not used the wraith since last poor speed vid as Im working quite a distance and not getting back till late.

Jay-Em · 12-07-2011, 11:04 AM

Yes, I am certain that the Titan 12t will run pretty well with a 72, or 74 spur with a 25t pinion.
I am not too sure about hard-core crawling though, given the fact that The Netherlands are rather low on rocks..

i am waiting for a 72t spur. My LHS was out. They had 25 t traxxas pinions though. I can't wait to see what kind of speed the Titan will get.

Let's just say, with the 72/25 combo, You're not going to crawl up Lynmouth's " rock castle", but You'll probably be pleasantly surprised by the speed that can be attained with the Titan 12t

Yeah, all that gearing blabbering is confusing by times, but finding out the best gear-ratio for your rig, and it's application( crawling, trailing, bashing, breakint sound-barrier), is part of the fun.

Remember thT the Titan has 1,6 x the torque of that 20t, so, You can roughly estimate that gearing can also be 1,5 to 1,8 times higher. I.e. 1:30 ( stock wraith) can easily be made 1:20. Just have a look at the gear-chart in the back of your manual to find out the combinations of spur-pinion that can be used.

Look at it this way: If the original gearing doesn't make a high-speed 6.5t even break a sweat, it's no big jump to realize that low amp stock motors are way under geared in the tested rig ( rule of thumb: the " hotter" ie, lower turn the motor, the more conservative you'd have to gear, that goes for brushed-motors, but that also goes for brushless, that have the power, but are very dependent on the C-rating of Your LiPo. A brushless will just pull more amps, the more You stress it. A brushed motor would have burnt the brushes and the commutator waaay before max amperage is pulled.)

-Enter posh voice-over- :
And this concludes, yet another invigorating channel 4 course on motor and gearing....

*hairy, musty 70's reject shuffles off behind cheap, mottled curtain*

gm0688 · 12-07-2011, 11:22 AM

Quote:

Originally Posted by crazee horse

Turnigy 7.4 5000mah 40-50c..............

A 2 cell isnt gonna be very fast so that sounds right. I M one of the AXIAL drivers and they will help you. If you want more spent a little and buy a 3 cell. Get ready for a new motor though and a BEC.

Jay-Em · 12-07-2011, 11:28 AM

What he sai^^

speed and good crawling = high-turn brushed + 3 cells + BEC

When staying on 2- cells, either one - speed, or crawling- has to give.

gm0688 · 12-07-2011, 11:29 AM

Quote:

Originally Posted by Psycho-Savvy

I am also curious about the Traxxas 550. Does it drop in with out any mods? Will the stock esc handle it? Does the stock pinion fit? Thanks

I used a stock 550 out of an EMAXX the second week. Fit right in with no grinding. It was tight. Still fit.

gm0688 · 12-07-2011, 11:39 AM

Quote:

Originally Posted by crazee horse

axial wraith with12t titan, on 5000mah 2s - YouTube

there she blows. the radio is stock, and all settings and calibration as should be. i was going to try and put the 23t in but i dont think it would fit ? its pretty tight already. thanks for the replies Jay-Em

Its strange to me what a big bost 3 cells is over 2.

Jay-Em · 12-07-2011, 11:50 AM

Quote:

Originally Posted by gm0688

Its strange to me what a big bost 3 cells is over 2.

For the 21t Titan, that's logic. It's a 14,4 v rated motor. The closer to it's rated voltage&rpm, the better it performs. It can even stand 4- cells...now there's an interesting proposition for speed-freaks..
The 12t Titan...well, I wouldn't bet on it surviving 11,6 v, since it's rated for 8,4 v max.

Me, I am mostly curious what the 12t Titan can muster at 7,4v.what I can squeeze out of it without burning it.

Haven't got a BEC yet, my ESC's are all LRP, and not meant for 3 cells.

crazee horse · 12-07-2011, 01:36 PM

I'll be back cod black ops is calling.

crazee horse · 12-07-2011, 01:42 PM

Hmmm theory is one thing but we need some comparison videos. Am turning after garage into work shop for my rc cars this weekend, so hopefully will get some wraith play time. After Christmas will buy a couple more lipo and a bec.

SC Convert · 12-07-2011, 02:57 PM

I used a tekin 17.5t redline /rs combo on 3s with esc timing boost and turbo dialed up for top end. 18/80 gearing and loved the crawl ability down low, midrange punch, and insane top end burst of speed. But again I wouldn't dream of puddle hopping with that setup. ( wet grass will short out the sensor connection causing it to default to unsensored mode until dry )

Jay-Em · 12-07-2011, 10:31 PM

Quote:

Originally Posted by crazee horse

Hmmm theory is one thing but we need some comparison videos. Am turning after garage into work shop for my rc cars this weekend, so hopefully will get some wraith play time. After Christmas will buy a couple more lipo and a bec.

Yup, hence my little tests with the nüvi.
Ordered me a 72, 73 and 75 spur to get to the nitty-gritty of it.

Sadly, I do not own a smart-phone, or cam that can do movies..

crazee horse · 12-10-2011, 10:32 AM

well i fitted my 23/80 combo today and she is skipping along. not by no means a speed demon, but quite a happy medium. i suppose i"d like a couple more mph, but its not too bad. after quite a beating she still ran cool as well ! always a bonus, though ok we did do a bit of water but also ran a lot after.

down side ? the gear cover doesnt fit !

jay, where do you order your gears from ? i have heard that traxxas spurs can be made to fit.................

Jay-Em · 12-10-2011, 01:20 PM

ordered via my LHS

traxxas 32p gear apparently fit. Some guys even made a complete traxxas Slash-4x4 slipper fit. Dropped right in.

With the Titan I'd go for a combi that gives You 1:3 to 1:3.2 i.e 15 tooth pinion and 47 or 48 tooth spur. Whatever combi gives a prime ratio of about 1:3.

I tried 25pinion with an 80 spur. Pretty fast for a crawler. Titan only got hot because I was constantly trying if the wraith would wheely. With kit-tires on dry pavement it does

spaghetti-od the punishers. replaced them with JunFac 10/15 cm punishers. no way I will be able to break those. they're really burly.
So, all-in-all, a 25/80 combi works pretty well for the Wraith imho.

tried 25 to 80 with my 4850kv 6.5 t . Holy Crap!!! Fast as a rat on fire. Got it up to 41km/h. Hit a curb crack!! right front-knuckle disintegrated..bezel of my Nuvi also broke....still worked, though

luckily I already ordered A hotracing knuckle-set. Next week: new knuckles, and on with the experimentation.

I am happy that You at least found a gearing combi that's fun to drive.

PS: gear cover didn"t fit??? I got a 25 t on an 80 spur. mine fits perfectly. Or do You mean that the Titan's axle is a bit too long? I had to dremel off about 3 mm before the cover fit, that's all..

crazee horse · 12-10-2011, 02:12 PM

Pretty sure its the pinion, though I could be wrong. The wraith is am absolute bastard to work on . I do like it when it works but when it doesn't, grrrrrrrr ! Will perhaps try with the dremyll tomorrow.

crazee horse · 12-11-2011, 01:27 PM

Been out in the

newly built workshop (ok its just a worktop and a piece of plasterboard so far) and inspected my shaft lol, I reckon I don't have 3mm to grind off ! Not unless I slide the pinion right back, but then the gears wouldn't line up properly.

Jay-Em · 12-11-2011, 02:26 PM

Well, to be honest, when i am not mudding, i mostlyleave the gear-cover off.
Fiddling it to "click" on the lower part of the gearbox makes me use "colourful language" quite proficiently, i might add..

All speed-experiments were done without the gear-cover.
Odd that Yours doesn't fit the 25t pinion. Indeed the 25 won't fit when using a 87t spur, but with my 80t it just fits fine, 3-racing pinions, losi pinions, traxxas pinions, they all fit within the gear-cover.

chromoly77 · 12-11-2011, 11:09 PM

Ok im traying different options on this i got the goat 21.5 brushless with 81/26 and still slow im traying a 75 and a 24 ill let you know temperatures and speed.

crazee horse · 12-12-2011, 12:48 PM

With bec, how quickly would 3s kill my titan ? Would it shorten its life that much? Just put a 3s in the wraith and it really sorted things out. After Christmas will be going down the 3p route I think. If it doesn't kill the motor to quickly.

12-07-2011, 09:54 AM	#42
Jay-Em Rock Crawler Join Date: Jan 2011 Location: Groningen, The Netherlands Posts: 528	Tried, for shi7 & giggles, my 6.5t exceleron BL with 80/25 (1:25) Wheelies on wet pavement [kit-tires are tha' bomb!], accelleration is Still rocket-like. I can make it jump a meter from mu' doormat. Weird sight. Praise the heavens for Jun-Fac punishers.... Didn't try measuring speed -it's raining cats&dogs overhere- will do that when it's dry again. Eye-ing it, i'd say I must be pushing 40km/h, wind in the back.... Wow... I guess I am right that the Wraith is seriously undergeared to get that cheap 20t behave as a semi-crawler motor. Soo..there IS a reason Losi initially choose the exceleron-line for it's brushless line-up. Last edited by Jay-Em; 12-07-2011 at 10:03 AM.

12-07-2011, 11:04 AM	#44
Jay-Em Rock Crawler Join Date: Jan 2011 Location: Groningen, The Netherlands Posts: 528	Yes, I am certain that the Titan 12t will run pretty well with a 72, or 74 spur with a 25t pinion. I am not too sure about hard-core crawling though, given the fact that The Netherlands are rather low on rocks.. i am waiting for a 72t spur. My LHS was out. They had 25 t traxxas pinions though. I can't wait to see what kind of speed the Titan will get. Let's just say, with the 72/25 combo, You're not going to crawl up Lynmouth's " rock castle", but You'll probably be pleasantly surprised by the speed that can be attained with the Titan 12t Yeah, all that gearing blabbering is confusing by times, but finding out the best gear-ratio for your rig, and it's application( crawling, trailing, bashing, breakint sound-barrier), is part of the fun. Remember thT the Titan has 1,6 x the torque of that 20t, so, You can roughly estimate that gearing can also be 1,5 to 1,8 times higher. I.e. 1:30 ( stock wraith) can easily be made 1:20. Just have a look at the gear-chart in the back of your manual to find out the combinations of spur-pinion that can be used. Look at it this way: If the original gearing doesn't make a high-speed 6.5t even break a sweat, it's no big jump to realize that low amp stock motors are way under geared in the tested rig ( rule of thumb: the " hotter" ie, lower turn the motor, the more conservative you'd have to gear, that goes for brushed-motors, but that also goes for brushless, that have the power, but are very dependent on the C-rating of Your LiPo. A brushless will just pull more amps, the more You stress it. A brushed motor would have burnt the brushes and the commutator waaay before max amperage is pulled.) -Enter posh voice-over- : And this concludes, yet another invigorating channel 4 course on motor and gearing.... hairy, musty 70's reject shuffles off behind cheap, mottled curtain Last edited by Jay-Em; 12-07-2011 at 11:32 AM.

12-10-2011, 01:20 PM	#55
Jay-Em Rock Crawler Join Date: Jan 2011 Location: Groningen, The Netherlands Posts: 528	ordered via my LHS traxxas 32p gear apparently fit. Some guys even made a complete traxxas Slash-4x4 slipper fit. Dropped right in. With the Titan I'd go for a combi that gives You 1:3 to 1:3.2 i.e 15 tooth pinion and 47 or 48 tooth spur. Whatever combi gives a prime ratio of about 1:3. I tried 25pinion with an 80 spur. Pretty fast for a crawler. Titan only got hot because I was constantly trying if the wraith would wheely. With kit-tires on dry pavement it does spaghetti-od the punishers. replaced them with JunFac 10/15 cm punishers. no way I will be able to break those. they're really burly. So, all-in-all, a 25/80 combi works pretty well for the Wraith imho. tried 25 to 80 with my 4850kv 6.5 t . Holy Crap!!! Fast as a rat on fire. Got it up to 41km/h. Hit a curb crack!! right front-knuckle disintegrated..bezel of my Nuvi also broke....still worked, though luckily I already ordered A hotracing knuckle-set. Next week: new knuckles, and on with the experimentation. I am happy that You at least found a gearing combi that's fun to drive. PS: gear cover didn"t fit??? I got a 25 t on an 80 spur. mine fits perfectly. Or do You mean that the Titan's axle is a bit too long? I had to dremel off about 3 mm before the cover fit, that's all.. Last edited by Jay-Em; 12-10-2011 at 01:50 PM.

12-05-2011, 04:14 PM	#41
Jay-Em Rock Crawler Join Date: Jan 2011 Location: Groningen, The Netherlands Posts: 528	did some on-line digging, and the blackfoot is 1:14 geared. with a stock 27t silvercan, that might work. I doubt there is a spur/pinion combi with that ratio that'll fit the Wraith gear-box though.. For the Titan i'd keep it at 1:20. Mainly because a Wraith is about 300 grams heavier, and has 14cm wheels instead of 13cm. If my rough calculations are correct, 72/25 should get You 25 to 28 km/h, and You'll have some crawling ability left. Good bashing territory in my book. I am not sure if that combi fits though. I am going to put my money where my mouth is, and i am going to get me a 72 spur and some 25 to 28 pinions tomorrow, just to see how close theory is to practice, and to ascertain how much of hot air my guesstimates contain..

12-07-2011, 10:43 AM	#43
crazee horse Rock Crawler Join Date: Jul 2010 Location: Great Britain Posts: 767	So your saying that the titan will be very happy bashing AND crawling on 25/72 ? I've been getting a bit confused with all this ratio talk lol not used the wraith since last poor speed vid as Im working quite a distance and not getting back till late.

12-07-2011, 11:28 AM	#46
Jay-Em Rock Crawler Join Date: Jan 2011 Location: Groningen, The Netherlands Posts: 528	What he sai^^ speed and good crawling = high-turn brushed + 3 cells + BEC When staying on 2- cells, either one - speed, or crawling- has to give.

12-07-2011, 01:36 PM	#50
crazee horse Rock Crawler Join Date: Jul 2010 Location: Great Britain Posts: 767	I'll be back cod black ops is calling.

12-07-2011, 01:42 PM	#51
crazee horse Rock Crawler Join Date: Jul 2010 Location: Great Britain Posts: 767	Hmmm theory is one thing but we need some comparison videos. Am turning after garage into work shop for my rc cars this weekend, so hopefully will get some wraith play time. After Christmas will buy a couple more lipo and a bec.

12-07-2011, 02:57 PM	#52
SC Convert Quarry Creeper Join Date: May 2011 Location: Ak Posts: 296	I used a tekin 17.5t redline /rs combo on 3s with esc timing boost and turbo dialed up for top end. 18/80 gearing and loved the crawl ability down low, midrange punch, and insane top end burst of speed. But again I wouldn't dream of puddle hopping with that setup. ( wet grass will short out the sensor connection causing it to default to unsensored mode until dry )

12-10-2011, 10:32 AM	#54
crazee horse Rock Crawler Join Date: Jul 2010 Location: Great Britain Posts: 767	well i fitted my 23/80 combo today and she is skipping along. not by no means a speed demon, but quite a happy medium. i suppose i"d like a couple more mph, but its not too bad. after quite a beating she still ran cool as well ! always a bonus, though ok we did do a bit of water but also ran a lot after. down side ? the gear cover doesnt fit ! jay, where do you order your gears from ? i have heard that traxxas spurs can be made to fit.................

12-10-2011, 02:12 PM	#56
crazee horse Rock Crawler Join Date: Jul 2010 Location: Great Britain Posts: 767	Pretty sure its the pinion, though I could be wrong. The wraith is am absolute bastard to work on . I do like it when it works but when it doesn't, grrrrrrrr ! Will perhaps try with the dremyll tomorrow.

12-11-2011, 01:27 PM	#57
crazee horse Rock Crawler Join Date: Jul 2010 Location: Great Britain Posts: 767	Been out in the newly built workshop (ok its just a worktop and a piece of plasterboard so far) and inspected my shaft lol, I reckon I don't have 3mm to grind off ! Not unless I slide the pinion right back, but then the gears wouldn't line up properly.

12-11-2011, 02:26 PM	#58
Jay-Em Rock Crawler Join Date: Jan 2011 Location: Groningen, The Netherlands Posts: 528	Well, to be honest, when i am not mudding, i mostlyleave the gear-cover off. Fiddling it to "click" on the lower part of the gearbox makes me use "colourful language" quite proficiently, i might add.. All speed-experiments were done without the gear-cover. Odd that Yours doesn't fit the 25t pinion. Indeed the 25 won't fit when using a 87t spur, but with my 80t it just fits fine, 3-racing pinions, losi pinions, traxxas pinions, they all fit within the gear-cover.

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12-11-2011, 11:09 PM	#59
chromoly77 Rock Stacker Join Date: Oct 2010 Location: chula vista/tijuana Posts: 62	Ok im traying different options on this i got the goat 21.5 brushless with 81/26 and still slow im traying a 75 and a 24 ill let you know temperatures and speed.

12-12-2011, 12:48 PM	#60
crazee horse Rock Crawler Join Date: Jul 2010 Location: Great Britain Posts: 767	With bec, how quickly would 3s kill my titan ? Would it shorten its life that much? Just put a 3s in the wraith and it really sorted things out. After Christmas will be going down the 3p route I think. If it doesn't kill the motor to quickly.

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