RCCrawler Forums

NickRummy · 08-04-2009, 09:20 AM

I'm sure someone has done it right? I am running a new motor with 1/8" shaft and want to convert to something more common. I'm running 16/60 right now and I'm need of more reduction. I want to go to 48p so need to figure out a spur that might work? Ideas?

speedjunkie · 08-04-2009, 09:40 AM

http://dhrc.rchomepage.com/RolloutCalc.htm

This link looks pretty useful. A 16/60 combo is pretty fast! If your spur gear is a 48, looks like a 11T pinion gear would get you back pretty close to the stock ratio. Have fun with the link and let us know how it turns out!

Mike

NickRummy · 08-04-2009, 10:04 AM

Yeh I can figure out the gearing difference. I'm more interested in finding a spur that will bolt onto the MRC trans that's a 48p. The MRC spur is an odd ball pitch.

soundcolor · 08-04-2009, 10:10 AM

try any of the gears for the Mini-t, slider, or mlst..

Top_Ramen · 08-04-2009, 10:26 AM

I think your only option is to use the .5 module pinions from novak. I think they make them down to 11T and they have a 1/8 shaft size.

sloppy · 08-04-2009, 10:36 AM

you can do it.. just like the old days school the newbies..

soundcolor · 08-04-2009, 10:53 AM

you know you could just use a drill and bit to get the size you wanted

Ralphy · 08-04-2009, 11:20 AM

I am pretty sure either losi and/or associated make a pinion gear set for the mini-t/ rc18 that will work just fine. when i say pretty sure it only relates to who makes it cause I have one with pinions from 9t to 14t and another set that goes up to 18t or so. I am running a 11 or 12t on my mini now with a trinity mini monster 17t pro motor and the gear reduction is spot on. I wouldnt waste too much more time looking for all new spur gear and such, just pick up a smaller pinion and get to crawlin bro! they are out there, check hobbytown usa, 3 racing, tower hobbies, or your local hooby shop, someone is bound to have what you need.

sloppy · 08-04-2009, 11:33 AM

Quote:

Originally Posted by sikax10

I am pretty sure either losi and/or associated make a pinion gear set for the mini-t/ rc18 that will work just fine. when i say pretty sure it only relates to who makes it cause I have one with pinions from 9t to 14t and another set that goes up to 18t or so. I am running a 11 or 12t on my mini now with a trinity mini monster 17t pro motor and the gear reduction is spot on. I wouldnt waste too much more time looking for all new spur gear and such, just pick up a smaller pinion and get to crawlin bro! they are out there, check hobbytown usa, 3 racing, tower hobbies, or your local hooby shop, someone is bound to have what you need.

I take it you missed the part about the motor having a 1/8 shaft and stock pinions not working

novak has pinions that will work I think nick is trying to not spend 12 bucks when he could spend 3

NickRummy · 08-04-2009, 12:00 PM

The whole reason for going to a 48p spur is so that I don't have to buy pinions. I have a TON of 48p pinions, 12/16/18/20 etc etc etc

The MRC spur is a 60t (the same as the mini t, slider blah blah) but it's the .5 module that I don't want to deal with.

I just got a Kimbrough 72t 48p spur and Sloppy is giving me a 66t 48p robinson spur so I'll see if I can't get one of those to fit on the MRC trans. If I can go to a 12/66 or 12/72 setup I think I'll be good to go. If it's 48p then I'll have lots of options to play with to get it right without having to buy a complete pinion set.

RivBlueNoma · 08-05-2009, 12:46 AM

Quote:

Originally Posted by NickRummy

I just got a Kimbrough 72t 48p spur and Sloppy is giving me a 66t 48p robinson spur so I'll see if I can't get one of those to fit on the MRC trans. If I can go to a 12/66 or 12/72 setup I think I'll be good to go. If it's 48p then I'll have lots of options to play with to get it right without having to buy a complete pinion set.

Keep us posted on how that works out. Id like to know if it cuts back on the noise at all. The noise from the tranny just drives me up the wall. I got mine used and thought it had issues until I saw everyone elses and heard the same aweful noise from all of them. :?

NickRummy · 08-05-2009, 06:11 AM

Quote:

Originally Posted by RivBlueNoma

Keep us posted on how that works out. Id like to know if it cuts back on the noise at all. The noise from the tranny just drives me up the wall. I got mine used and thought it had issues until I saw everyone elses and heard the same aweful noise from all of them. :?

Well I used a 25/64" drill bit and drilled out the middle of the new spur and was able to press the center hub into it from the MRC trans. The problem was the 66t spur is really big. It JUST barely cleared the motor shaft meaning there is no room at all for a pinion. I could probably start hacking away at the motor plate but that's to involved for me.

I'm thinking about just using the axial trans and an adapter for the motor so I have more options.

soundcolor · 08-05-2009, 07:36 AM

I completely fail to understand your problem.
You want more gear reduction. Ok.
You say your motor has a 1/8th output shaft. Ok.

And your wanting to drop the pinion gear...
or is it the spur gear?

at any rate, it doesnt really matter.
If you want to go with a bigger pinion, then go get a 50t mini-t gear and be done with it, they sell them at every LHS I have ever been to, or you could just order one online.

If you want to go with a smaller spur gear, thats no problem as well, just go buy a 9 or 10t and drill it out to 1/8th. No problem.

conversely, if you want to save yourself alot of trouble, and be able to use any gear you can think of, then just break out the ole 80 grit sandpaper, spin the motor up to speed and sand it down to a more common size.

Seems to me like you are making a mountain out of a mole hill.

NickRummy · 08-05-2009, 08:01 AM

Quote:

Originally Posted by soundcolor

I completely fail to understand your problem.

I want to convert the MRC trans to a 48p spur and at the same time gear down a bit from the stock 16/60 gearing. The motor is 1/8" which is a standard size and i have a ton of 48p pinions to fit the motor which is the reasoning for trying to fit a 48p spur to the MRC trans. I don't want to go out and buy a bunch of pinions and spurs that are odd ball pitch and I can only use on this truck.

The smallest 48p pinion you can get is 12t. A 66t 48p spur on the MRC trans will not mesh with that 12t pinion. So I need to find a smaller 48p spur which I'm not sure is available.

soundcolor · 08-05-2009, 08:31 AM

ok, I think I get what your wanting,
I'm guessing that the motor you have has alot more speed than the stock motor as well.

at any rate, it still doesn't matter. You are wanting to slow your rig down by way of more gear reduction at the motor end. O.k. Here is what I would suggest.

If you are still running a 280 sized motor then you are going to have to be careful as to which pinion you run, because you will rapidly run out of room with the motor plate. If thats the case then what you need to do is let us know which motor you are running so we (all the members of this site, and the MRC forum in particular) can help give you an idea of which size gear you need to be running. That will save you alot of steps in picking the right gear.

If you are attmepting to run a larger motor on the MRC then you need to get a "big block" motor plate from the Mini-T (they are the same thing). At which point you will have all kinds of room to get whatever gear you want in there. If this is where you are at, then the best advice I could give you is to check the MLST, or the Mini Slider spur gears. They might have the same pitch as the MRC but should be available in a wider selection of sizes. Then its just a matter of matching up a pinion.

Heres is another suggestion that my work, round up your pinions and your rig and head on down to your LHS and start going through all the gears they have so that you can find exactly the righ spur/pinion you are looking for.

I understand that you are wanting to be able to use what you already have to save you from spending money. However, almost every motor that could possibly be fit to an MRC has been fit on one by someone on here, Without knowing which motor your running, and what style of crawling you are wanting to do (rock racing, scale, comp.... et. al.) then its really hard to help.

Help us help you

RivBlueNoma · 08-05-2009, 08:49 AM

Heres a 60 tooth. http://www3.towerhobbies.com/cgi-bin...?&I=LXEY18&P=7

The center hole looks a pretty large though. You might have a hard time keeping it centered.

NickRummy · 08-05-2009, 09:13 AM

Here's my build.

Rummy's MRC Jeep

I'm trying the 400 size Himark cobalt motor. It's already as close to the housing as it can get. It has 16mm mounting holes on it so I modded the motor plate to accept that. Theres not much more room on the motor plate to allow for the use of larger gears.

Is the 400 size motor a "big block" in which case I can get a mini t motor plate?

sloppy · 08-05-2009, 10:44 AM

Quote:

Originally Posted by soundcolor

If you want to go with a smaller spur gear, thats no problem as well, just go buy a 9 or 10t and drill it out to 1/8th. No problem.

have you ever drilled out a 9-10T pinion to 1/8"???

nick the 400 is not a "big block" but it still may solve the issue of no more motor plate that you have now.. looks like nothing between 60 and 66 which sucks.. I was hoping for a 62 or 64 in there then I would be able to do it and not hit the drive shaft.. its to bad 64P wouldnt hold up we could do anything in that pitch..

mini LST has a smaller spur 52 or 54.. slider is 60 I think none of them have large spurs stock.. if there are aftermarket ones that may be a option..

soundcolor · 08-05-2009, 11:09 AM

Quote:

Originally Posted by sloppy

have you ever drilled out a 9-10T pinion to 1/8"???

Yes i have, Last friday actually. And I didnt even use a drill press, just a pair of vice grips and a drill. Not all that hard.

nick the 400 is not a "big block" but it still may solve the issue of no more motor plate that you have now.. looks like nothing between 60 and 66 which sucks.. I was hoping for a 62 or 64 in there then I would be able to do it and not hit the drive shaft.. its to bad 64P wouldnt hold up we could do anything in that pitch..

mini LST has a smaller spur 52 or 54.. slider is 60 I think none of them have large spurs stock.. if there are aftermarket ones that may be a option..

If you are running a 400, then the big block plate may well be the answer to your prayers.

sloppy · 08-05-2009, 11:29 AM

really was it a 9 or 10? have any pictures of the pinion? and what pitch was the pinion?

08-04-2009, 09:20 AM	#1
NickRummy RCC Addict Join Date: Aug 2005 Location: Akron Posts: 1,784	Converting MRC trans and motor to 48p? I'm sure someone has done it right? I am running a new motor with 1/8" shaft and want to convert to something more common. I'm running 16/60 right now and I'm need of more reduction. I want to go to 48p so need to figure out a spur that might work? Ideas?

08-04-2009, 09:40 AM	#2
speedjunkie Pebble Pounder Join Date: Jan 2009 Location: Wichita Posts: 120	http://dhrc.rchomepage.com/RolloutCalc.htm This link looks pretty useful. A 16/60 combo is pretty fast! If your spur gear is a 48, looks like a 11T pinion gear would get you back pretty close to the stock ratio. Have fun with the link and let us know how it turns out! Mike

08-04-2009, 10:04 AM	#3
NickRummy RCC Addict Join Date: Aug 2005 Location: Akron Posts: 1,784	Yeh I can figure out the gearing difference. I'm more interested in finding a spur that will bolt onto the MRC trans that's a 48p. The MRC spur is an odd ball pitch.

08-04-2009, 10:10 AM	#4
soundcolor Rock Crawler Join Date: Mar 2009 Location: Cottontown Posts: 880	try any of the gears for the Mini-t, slider, or mlst..

08-04-2009, 10:26 AM	#5
Top_Ramen Quarry Creeper Join Date: Jun 2008 Location: Honolulu Posts: 421	I think your only option is to use the .5 module pinions from novak. I think they make them down to 11T and they have a 1/8 shaft size.

08-04-2009, 10:36 AM	#6
sloppy I wanna be Dave Join Date: May 2006 Location: akron Posts: 4,054	you can do it.. just like the old days school the newbies..

08-04-2009, 10:53 AM	#7
soundcolor Rock Crawler Join Date: Mar 2009 Location: Cottontown Posts: 880	you know you could just use a drill and bit to get the size you wanted

08-04-2009, 11:20 AM	#8
Ralphy Holdin my 40oz. Join Date: May 2008 Location: Somewhere in Colorado Posts: 434	I am pretty sure either losi and/or associated make a pinion gear set for the mini-t/ rc18 that will work just fine. when i say pretty sure it only relates to who makes it cause I have one with pinions from 9t to 14t and another set that goes up to 18t or so. I am running a 11 or 12t on my mini now with a trinity mini monster 17t pro motor and the gear reduction is spot on. I wouldnt waste too much more time looking for all new spur gear and such, just pick up a smaller pinion and get to crawlin bro! they are out there, check hobbytown usa, 3 racing, tower hobbies, or your local hooby shop, someone is bound to have what you need.

08-04-2009, 12:00 PM	#10
NickRummy RCC Addict Join Date: Aug 2005 Location: Akron Posts: 1,784	The whole reason for going to a 48p spur is so that I don't have to buy pinions. I have a TON of 48p pinions, 12/16/18/20 etc etc etc The MRC spur is a 60t (the same as the mini t, slider blah blah) but it's the .5 module that I don't want to deal with. I just got a Kimbrough 72t 48p spur and Sloppy is giving me a 66t 48p robinson spur so I'll see if I can't get one of those to fit on the MRC trans. If I can go to a 12/66 or 12/72 setup I think I'll be good to go. If it's 48p then I'll have lots of options to play with to get it right without having to buy a complete pinion set.

08-05-2009, 07:36 AM	#13
soundcolor Rock Crawler Join Date: Mar 2009 Location: Cottontown Posts: 880	I completely fail to understand your problem. You want more gear reduction. Ok. You say your motor has a 1/8th output shaft. Ok. And your wanting to drop the pinion gear... or is it the spur gear? at any rate, it doesnt really matter. If you want to go with a bigger pinion, then go get a 50t mini-t gear and be done with it, they sell them at every LHS I have ever been to, or you could just order one online. If you want to go with a smaller spur gear, thats no problem as well, just go buy a 9 or 10t and drill it out to 1/8th. No problem. conversely, if you want to save yourself alot of trouble, and be able to use any gear you can think of, then just break out the ole 80 grit sandpaper, spin the motor up to speed and sand it down to a more common size. Seems to me like you are making a mountain out of a mole hill.

08-05-2009, 08:31 AM	#15
soundcolor Rock Crawler Join Date: Mar 2009 Location: Cottontown Posts: 880	ok, I think I get what your wanting, I'm guessing that the motor you have has alot more speed than the stock motor as well. at any rate, it still doesn't matter. You are wanting to slow your rig down by way of more gear reduction at the motor end. O.k. Here is what I would suggest. If you are still running a 280 sized motor then you are going to have to be careful as to which pinion you run, because you will rapidly run out of room with the motor plate. If thats the case then what you need to do is let us know which motor you are running so we (all the members of this site, and the MRC forum in particular) can help give you an idea of which size gear you need to be running. That will save you alot of steps in picking the right gear. If you are attmepting to run a larger motor on the MRC then you need to get a "big block" motor plate from the Mini-T (they are the same thing). At which point you will have all kinds of room to get whatever gear you want in there. If this is where you are at, then the best advice I could give you is to check the MLST, or the Mini Slider spur gears. They might have the same pitch as the MRC but should be available in a wider selection of sizes. Then its just a matter of matching up a pinion. Heres is another suggestion that my work, round up your pinions and your rig and head on down to your LHS and start going through all the gears they have so that you can find exactly the righ spur/pinion you are looking for. I understand that you are wanting to be able to use what you already have to save you from spending money. However, almost every motor that could possibly be fit to an MRC has been fit on one by someone on here, Without knowing which motor your running, and what style of crawling you are wanting to do (rock racing, scale, comp.... et. al.) then its really hard to help. Help us help you

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08-05-2009, 08:49 AM	#16
RivBlueNoma Rock Crawler Join Date: Feb 2006 Location: Cutting Comms Posts: 752	Heres a 60 tooth. http://www3.towerhobbies.com/cgi-bin...?&I=LXEY18&P=7 The center hole looks a pretty large though. You might have a hard time keeping it centered.

08-05-2009, 09:13 AM	#17
NickRummy RCC Addict Join Date: Aug 2005 Location: Akron Posts: 1,784	Here's my build. Rummy's MRC Jeep I'm trying the 400 size Himark cobalt motor. It's already as close to the housing as it can get. It has 16mm mounting holes on it so I modded the motor plate to accept that. Theres not much more room on the motor plate to allow for the use of larger gears. Is the 400 size motor a "big block" in which case I can get a mini t motor plate?

08-05-2009, 11:29 AM	#20
sloppy I wanna be Dave Join Date: May 2006 Location: akron Posts: 4,054	really was it a 9 or 10? have any pictures of the pinion? and what pitch was the pinion?

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Thread: Converting MRC trans and motor to 48p?