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cummingsman29
08-27-2010, 10:15 PM
Hey guys, just Want to see what everyone is running for a *gear reduction unit and at a good price!
Thanks!

fhhhstix
08-27-2010, 10:20 PM
I use the Integy 4:1 and it requires no modification. It is about $40.

http://i574.photobucket.com/albums/ss185/brokenb4/Green%20King/4to1gearreduction003.jpg

Stepside
08-27-2010, 10:28 PM
Donny,

Go w/ a GD-600 if your looking to control cost.

http://cgi.ebay.com/Great-Planes-ElectriFly-GD-600-Gear-Drive2-5-1-GPMG0850-/170531525123?pt=LH_DefaultDomain_0&hash=item27b4789203#ht_1245wt_741

Mount it to your motor, and and file the shaft down to accept a gear and you're set.

http://img.photobucket.com/albums/v492/monsterbeetleguy/GD600%20Install/gd600006.jpg

http://img.photobucket.com/albums/v492/monsterbeetleguy/GD600%20Install/gd600005.jpg

Tamiya Cowboy
08-27-2010, 10:44 PM
You can also go with a 55 turn motor and a 6 tooth pnion for less money it comes out to be the same rpm's at the out put on the tranny in 1st gear as any 4 to 1 with a stock 550 can motor. Also RC4WD makes a 2 to 1 up to a 5 to 1 for the clodbuster I have taken this and mounted the motor backwards in my black tri axle they are all alum and cheep. With the GD600 you can also mount it on the out put of the tranny Idid that on my Hay Hauler this takes the stress of the load off the tranny by mounting it on the output.

cummingsman29
08-27-2010, 11:06 PM
Thanks guys, I need 3 of them so just wanted to get some info on them the Pmd one I have in one of the trucks is good buy not 140.00 good.

Tamiya Cowboy
08-28-2010, 12:10 AM
Thanks guys, I need 3 of them so just wanted to get some info on them the Pmd one I have in one of the trucks is good buy not 140.00 good.

LOL yeah the funny thing about them is you only buy one....One Time

Tamiya Cowboy
08-28-2010, 01:20 AM
Donny here is a pick of what I was talking about with the clod gear reduction.
http://i58.photobucket.com/albums/g276/theonlytamiyacowboy/IMG_1764.jpg
http://i58.photobucket.com/albums/g276/theonlytamiyacowboy/IMG_1760.jpg

tc1cat
08-28-2010, 08:01 AM
One thing not mentioned with the GD600 is that you have to either raise the tranny up by about .125" or lower your steering and shifting servos that amount or any combination of that. I have used both the GD600 and the Integy GRU. I like the metal case of the Integy but not the "noise" from it. Also the Integy is easier to mount than the GD600. Kind of a toss up as to which one is the best to me.

Juganought
08-28-2010, 01:34 PM
Have you guys a link to the the elusive six tooth pinion? just cant find one:eek:

Blueshirt
08-28-2010, 02:13 PM
Paul, do yu have a pick of that GRU from the front of the tranny you could post?

SonoranWraith
08-28-2010, 04:46 PM
Have you guys a link to the the elusive six tooth pinion? just cant find one:eek:

RC4wd has 6, 7, 8 etc.

Rogue
08-31-2010, 09:35 AM
Unless you are set on having more than a single speed, I use gearmotors like this one.

In my Wedico
http://i72.photobucket.com/albums/i178/King-Rick/WDC/Transfrombottom1.jpg

And one in my Tamiya
http://i72.photobucket.com/albums/i178/King-Rick/Single%20Axle/Picture395.jpg

Extremely small, powerful, and quiet. And cheap !!

Juganought
08-31-2010, 10:50 AM
Extremely small, powerful, and quiet. And cheap !!

@ Rogue.....What motor is this, and specs?

Thanx

Rogue
08-31-2010, 11:54 AM
Extremely small, powerful, and quiet. And cheap !!

@ Rogue.....What motor is this, and specs?

Thanx

Sorry, forgot to supply the link. Here you go
http://banebots.com/c/MP-28XXX-385

ihbuilder
08-31-2010, 12:05 PM
Rick are you running the 20:1 ? I was thinking putting 1 in my merk since I robed the 3 speed out of it :rolleyes: .

Rogue
08-31-2010, 12:18 PM
Rick are you running the 20:1 ? I was thinking putting 1 in my merk since I robed the 3 speed out of it :rolleyes: .

Yeppers !! Speed is something close to the same as a GD reduced 3 spd in 2nd gear.

I suppose you could figure it out mathematically to see what works best for you. I can't do it like that. I'm one of those "feel good" guys. If it feels good, go for it!! Trial and error is my best friend

ihbuilder
08-31-2010, 02:48 PM
Thanks rick , yea I'll sit and do the math or do t&e depends on who of the 2 of me wakes up in the morn :p .

Lil Giants
09-03-2010, 12:52 AM
I'm a calculating kind of guy, so I did the math and went with a 5:1 reduction. I decided to run a Novak 540, 55 turn motor on this box, because I'm a power hungry guy! I ended up figuring out the Wedico final drive ratio in 3 gear, the stock Wedico motor RPMs, and the actual wheel speed. I found with the 5:1 ratio and the 55T motor on 12 volts, plus the 3:1 axle diff ratio, the speed would be almost identical to the stock Wedico trans in 3rd, with the Buhler motor. I expect no shortage of power, .....

I think your math is a bit out Nathan. :P

I find my trks have a good combo of both power & speed with dual Beuhlers, tam trans in 2nd and I have an additional 6.2 reduction within the twin motor coupler & tam transfer case. I forget exactly what the stock reduction is in 2nd with drive axles (17:1?)... total reduction is approx 105:1 with motors running around 5000rpm.

What rpm is the 55 turn 12v Novak motor?

fhhhstix
09-03-2010, 09:37 PM
Joe we put 5 55turn motors on my dyno and they ranged from 4800-5900 rpm. Instead of running the dyno with a 12 power supply and regulating the dyno to 7.2v we ran the dyno with 2 of my good NiMH 7.2v batteries which give a better reading. We ran all 5 motors on one battery and then did it again with the other battery. The 12v power supply is fine to break in a motor but using a battery pack will give you a better reading of the motor this is how we used to do it for our race cars.

Lil Giants
09-04-2010, 12:03 AM
The big grippers I'm running are a bit taller than the stock tams of 83mm and I use the 12 tooth plastic pinion, that comes with wdc motors, on the output shaft from the twin motor coupler into the tam trans... the final drive output is somewheres around 50 rpm at the drive axle... and you're talking having ten times that with your wdc? That seems pretty quick for a heavy haul tractor.

The white tractor in my vids is usually running around in 2nd. I rarely ever use 1st. And flip into 3rd running empty, which is a bit faster than walking.

CustomRCmodels
09-04-2010, 12:25 AM
The big grippers I'm running are a bit taller than the stock tams of 83mm and I use the 12 tooth plastic pinion, that comes with wdc motors, on the output shaft from the twin motor coupler into the tam trans... the final drive output is somewheres around 50 rpm at the drive axle... and you're talking having ten times that with your wdc? That seems pretty quick for a heavy haul tractor.

The white tractor in my vids is usually running around in 2nd. I rarely ever use 1st. And flip into 3rd running empty, which is a bit faster than walking.

Joe ,
Don’t you use the 3:1 version of the Wedico double-motor coupler type I made up for Ric ?
I don’t remember if I had send you the gear to do that yourself , or if you did get it from Ric ?

CustomRCmodels
09-04-2010, 12:41 AM
Joe we put 5 55turn motors on my dyno and they ranged from 4800-5900 rpm. Instead of running the dyno with a 12 power supply and regulating the dyno to 7.2v we ran the dyno with 2 of my good NiMH 7.2v batteries which give a better reading. We ran all 5 motors on one battery and then did it again with the other battery. The 12v power supply is fine to break in a motor but using a battery pack will give you a better reading of the motor this is how we used to do it for our race cars.

CAT-man
What dyno do you use ?
A typical 55 turn motor should have around 8000 rpm’s with zero timing .
Your readings look like readings you get on a dyno with a internal stabilized 5 volt supply , no matter what you connect to it .

Here are my test-results from 2002
Comparing my own WWR-Truckpuller vs the LRP Truckpuller ( 55 turn vs 80 turn )
http://www.customrcmodels.com/130d365f0.jpg

and here my WWR-Truckpuller vs stock Mabuchi 540 ( 55 turn vs 27 turn )
http://www.customrcmodels.com/130e375b0.jpg

here you can read my write up from back then :
http://www.customrcmodels.com/id442.htm (http://www.customrcmodels.com/id442.htm)

CustomRCmodels
09-04-2010, 12:44 AM
Argh! :D Joe, I know what I did wrong. After reading what you typed I realized it. I can't believe I didn't catch my mistake! Not more then a month ago I answered a question and wrote a 'how to' in the process on Scale 4x4, when a guy asked about ratios.

That completely slipped my mind. Can you guess what I didn't do? I feel stupid now! :D

Guess I need a different planetary drive now.

did you forget the ratio between motor and the transmission ?
since I wanted to asked you about that ….

fhhhstix
09-04-2010, 12:56 AM
Willy it is a Phantom Facts Machine. The 55 we tested were cheap lathe motors. But using a power supply and setting the dyno voltage at 7.2 volts gave us higher rpms than the battery did. it takes a lot of power to spin up the fly wheel and a battery can't keep up like a power supply can. That is why we use the battery to simulate what will happen at the track. Yes Willy they will spin close to 8000 rpm on a free spin but just like your 55 in the read out above the max power is at 4168 rpm.

Espeefan
09-04-2010, 12:58 AM
did you forget the ratio between motor and the transmission ?
since I wanted to asked you about that ….

I sure did! :D Sometimes it's the simplest things. You know, I looked up the ratios of the trans and the axles, but forgot about the pinion and spur gears! D'oh. The Wedico AWD 3 speed has a 24 tooth spur gear and it comes with a 14 tooth brass pinion gear. The motor however comes with a 13 and 12 tooth plastic pinion gear. The motor mount is not adjustable on the Wedico 3 speed, so I'm betting they want you to use the brass pinion that comes with the trans. That gives me a missing ratio, which I failed to factor into my calculations, of 1.71. I also have the belt drive reduction that I can't count, without pulling the plate off the trans. Gonna have to do that too!

CustomRCmodels
09-04-2010, 01:03 AM
Willy it is a Phantom Facts Machine. The 55 we tested were cheap lathe motors. But using a power supply and setting the dyno voltage at 7.2 volts gave us higher rpms than the battery did. it takes a lot of power to spin up the fly wheel and a battery can't keep up like a power supply can. That is why we use the battery to simulate what will happen at the track. Yes Willy they will spin close to 8000 rpm on a free spin but just like your 55 in the read out above the max power is at 4168 rpm.

ok , cool Travis ,
I didn’t want to get in to this yet , load and no load , just was checking on your numbers ,
so we are on the same page here !

Lil Giants
09-04-2010, 01:44 AM
Joe ,
Don’t you use the 3:1 version of the Wedico double-motor coupler type I made up for Ric ?
I don’t remember if I had send you the gear to do that yourself , or if you did get it from Ric ?

Yeah, that's part of the 6.2 additional reduction. 3:1 in the twin motor coupler and 2.1 in the t-case.

Nathan, with the 55 turn motor and 3:1 axles, I'd think you'd want 25 or 30:1 planetary box. Your wdc tires will be about 15mm smaller diameter.

Espeefan
09-04-2010, 10:49 AM
Joe, thanks. I went back and re-did my calculations. I removed the trans cover and counted teeth on the spur gear as well as the belt drive reduction. Here are my findings, assuming I stick with the 3:1 axles.

1st gear final drive ratio is 66.87:1
2nd gear final drive ratio is 33.3:1
3rd gear final drive ratio is 16.65:1

Just for grins, I also calculated the actual mph in each gear. Had to see what kind of ground this truck would cover. One revolution of the tires covers 9" or .75 feet. Running a 6,000 RPM motor, 1st gear is good for .75 mph. 2nd, 1.5 mph. 3rd, 3 mph.

Hub speed is 89 RPM in 1st, 180 RPM in 2nd, and 360 RPM in 3rd.

Looks like a Novak on 12 volts would need a 16:1 planetary and 4:1 Rust axles to come out somewhere between the stock driveline's 2nd and 3rd gear speeds. About 1.8 mph.

Or with a 20:1 planetary and 4:1 axles, I'd be getting about 1.45 mph. A little under 2nd gear speeds.

If I stick with Wedico axles 3:1, a 20:1 planetary will give me about 1.9 mph.
16:1 planetary and 3:1 axles gives about 2.4 mph.

That looks much better!

Rogue
09-04-2010, 11:11 AM
WOW..... You guys are way beyond my scope of intensity when it comes to figure gearing. Reading all these responses, I would think we're trying to decipher Einstein's theory of Realitivity :p:D

Espeefan
09-04-2010, 11:17 AM
Rick... :D

So Rick, how much power do those little 385 motors have? I'm really curious if they struggle at all with a heavy load? Do they notice the load much, with the reduction? I'd be curious to see a video....

Rogue
09-04-2010, 11:59 AM
I don't have any visual proof of it, but I have run my single axle and flatbed doubles around with a 12 pack on each trailer. At the time tho, the thought never crossed my mind to get a GVW on it.
Did it pull it? Yes...... Did it struggle doing it? It did, but not to anywhere near the degree that i was expecting. I was actually impressed with the capability of the 385 canned motor.
The biggest selling point for me on these gearmotors is the fact that there is ZERO backlash in them. Unlike a Tamiya 3 speed which has a ridiculous amount of slop in it.

Espeefan
09-04-2010, 12:21 PM
You should do it again, Rick and get some video! I do believe you though. That's pretty strong for a little motor. A 12 pack is about ten pounds, I think. I hear you on the tranny slop. The Wedicos have that too. You'll get that anytime you have slots in a gear, so that the dogs can engage the gears better.

Espeefan
09-04-2010, 03:32 PM
I ran into an interesting problem with Banebots today. I was going to place an order for the smaller planetary drives, which come with the 385 motor. It looks like they are discontinued now. The only one that is still available is the 36mm, 16:1 planetary drive with the the 385 motor. Seems Banebots is replacing them with the larger P60, 540/550 can motor boxes. The ratios are the same, but the smaller 385 sized boxes would fit better in some cases. I ended up going with a P60 20:1 instead. Just thought I'd give a heads up for the guys considering the smaller 36 and 28mm planetary drives.

Rogue
09-04-2010, 07:48 PM
Another alternative is this. Scott (rcguy farms) turned me on to these years ago.

Look for the B series beetle motor halfway down the page
http://www.robotmarketplace.com/store_ant_motors.html

SonoranWraith
09-04-2010, 09:51 PM
x2 on the beetle motors. Very nice size with good power and variety of gearheads in a small pkg.

fhhhstix
09-04-2010, 10:35 PM
I have 2 of the beetle 104's in my tracked CAT tractor and they work great.

Travis

Espeefan
09-04-2010, 11:23 PM
That looks like a great motor too. Maybe for a future project!

oldboy
09-13-2010, 05:50 PM
I just reduce the size of the pinion gear from stock 13 or 15 to 10 or 8teeth and that slows them down real quick :) :)

John

wolfws6
12-08-2013, 07:20 PM
So I have decided to run a 55t motor and 6 tooth pinion. I need to slow the truck down but I need a lot of extra torque over the stock motor to pull this massive 45lb toy hauler trailer around. BUT,,,,,,, Here is the magic question????? How much slower will it be vs 55t motor 6 tooth pinion and stock tires vs low pros? I'm running rc4wd low pro tires. They are 73mm tall vs stock Tamiya's 83mm. So theoretically it would be even slower maybe to slow. I want realistic speed more torque. Any suggestions Please help!!!!!

Espeefan
12-08-2013, 07:59 PM
You won't loose much speed by decreasing the tire size 10mm. Only about a 1.123% decrease in speed overall. Not enough to worry about.

If you know what your motor's Kv rating is (RPM per volt), you could actually calculate the speeds of the truck in all three gears.

wolfws6
12-08-2013, 08:07 PM
You won't loose much speed by decreasing the tire size 10mm. Only about a 1.123% decrease in speed overall. Not enough to worry about.

If you know what your motor's Kv rating is (RPM per volt), you could actually calculate the speeds of the truck in all three gears.

Thank you!!!!!! For answering my question.

Lil Giants
12-08-2013, 11:26 PM
73 vs 83 = approx. 12% less diameter... even measuring the circumference, 230 vs 262 is 12% less.

How did you calculate it only being 1.123% decrease overall?

Espeefan
12-09-2013, 12:00 AM
73 vs 83 = approx. 12% less diameter... even measuring the circumference, 230 vs 262 is 12% less.

How did you calculate it only being 1.123% decrease overall?

The decimal point got me Joe. My apologies wolfws6. Joe is correct. The odd number is because I thought I would convert the metric to English, to double check some roll out figures (distance traveled per revolution). Would have been 11.23%, had I paid attention.