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-   -   frustrating 19 turn motors (https://www.rctech.net/forum/electric-road/39022-frustrating-19-turn-motors.html)

TheCoolCanFanMan 04-23-2004 06:09 AM

frustrating 19 turn motors
 
I have a Losi xxx-s 90 spur
I have bought 3 new 19turn motors and they vary so much with regards to gearing, revs, and tork

Reedy Quad 513, when I first spun this up on a mates dyno a read out of 26,000 rpm, 'PANTS' what brushes/spings do I need to get more revs?? or am I doing something wrong!!

Reedy Quad 514 yet to be got, but is a dyno version of the 513

Reedy chrome, this seems to have more revs but less tork how do I gear ?? what brushes/spings do I need ??

Chameleon 2 spun this one up and got 34,000 rpm
used 4499's and sounds like its screaming to be used and abused

frustrated of UK :cry:

David Root 04-23-2004 06:24 AM

There is more to life than RPM
 
Try Reedy #767 brushes and red springs on boty. Make sure the arm is shimmed in the center of the magnetic field. Make Xtra sure the brush hoods are lined up exactly right so the brush wears right in the center. Should be good.

Cain 04-23-2004 06:25 AM

from what I have been reading you would want to setup your quad mags like this:

767s all around or on positive side, 766 on other side

Fiddlestick settings of 7.0+ and 6.5- ( or purple springs +, red springs - ) You may have to tweak this alittle stiffer depending how much arcing you get.

Align the hoods straight across. This is done to retard the timing some as 24 degrees of timing on this motor really is too much from what I have been reading. If allowed, you can cut the inner tab and reduce the timing to a max of 18 degrees. I use about 12 and the motor ran a whole lot better.


Make sure that you brushes are fully seated, especially if you go with 767s. 766s actually take awhile to seat, I had to run mine for about 20 minutes before it finally seated.

After you seat the brushes, give the comm a light cut and reseat for about 1 minute. This should give you max power.

What Dyno are you using? From what I understand the Quad Mag makes more torque, so you have to gear it up in you vehicle to see it perform. So on some dyno's like the Fantom it will look bad if you only hunt for RPM, but when actually running the motor and gearing it up, it really screams around the track.

Cain 04-23-2004 06:28 AM

Another thing 766s make more torque but also less RPM. the 767s should bump up the RPM you are seeing.

TheCoolCanFanMan 04-23-2004 06:47 AM

Thanks guys for all you info it is much appreciated, any more tips keep them coming :D

Cain 04-23-2004 07:00 AM

I think when you have motors that scream RPMs but not as much torque you gear alittle lower. Could be wrong however as motors I use have alot of torque.

I will be running a Reedy Silver can 19T motor today to test it out and see if it will be my backup motor or practice motor. I currently have it configured like this:

766s all around ( figured more torque would be good )
7.0+ , 6.5- FS settings

The hoods looked pretty good so I wasn't worried too much about aligning them.

I will be running this in a TC3 so it may give you some idea how a touring car should run with this motor.

As for the Quad mag's, They can run really strong when geared right. The local Factory driver gets his Chameleons to fly off the shelve and his Quad Mags are fast too, my chameleons only wanted to fly in the trash can :lol:

raving-monkey 04-23-2004 07:53 AM

if i am correct softer springs will give more rpm, where as harder ones will give more torque

TheCoolCanFanMan 04-23-2004 08:31 AM

sorry guy's no to sure what you mean by 7.0+ , 6.5- FS settings ??:confused: remember I come from that lttle planet they call UK :D

Cain 04-23-2004 08:44 AM

A fiddlestick is a little device that you can measure the tension of the springs on the brush. Not sure where you would get one in the UK however.

Basically I would start with purple + / red - spring settings with the Quad Mag as it seems to like more tension, especially with all that timing.

Seriously, if the rules allow, reduce the timing. I liked my Quad Mag much better with less timing on it.

berger 04-23-2004 08:47 AM


Originally posted by raving-monkey
if i am correct softer springs will give more rpm, where as harder ones will give more torque
The spring tension required is governed by the load that the motor is under. So as the dyno can't match the varying loads of the track then the dyno can't really help with accurately guaging what the best spring tension will be.
If the springs are too hard then the motor will rev higher with softer springs.
The spring tension should never be less than what is necessary to hold the brush onto the commutator.
The more current that is drawn then the more the brushes are pushed away from the comm so the stiffer the springs need to be.
When the grip is low and the wheels spin rather than grip then the motor draws less current.
So on low grip tracks less spring tension is the way to go. But you can't just go ridiculously soft.
On higher grip tracks then you have choices, going stiffer on the spings and gearing up to take advantage of torque is one different way.

raving-monkey 04-23-2004 08:55 AM

here in UK we aren't allowed to change the timing (unless you are running at a none BRCA affiliated club how ever:nod: :p :lol: )

berger 04-23-2004 09:04 AM


Originally posted by raving-monkey
here in UK we aren't allowed to change the timing (unless you are running at a none BRCA affiliated club how ever:nod: :p :lol: )
What section of the rulebook is that under, i can find no mention of timing changes being illegal. Under section 5 "motors" timing changes are not mentioned just that legal motors decided by the brca electric board are to be used.

raving-monkey 04-23-2004 09:56 AM

yeah, but the BRCA limit is 24 degrees. i was talking to this guy that runs a club and he said it says in the club handbook the BRCA limit is 24 degrees i think.

i can check up for ya if ya want.

berger 04-23-2004 09:59 AM

Under section 5 of the 2003 rules which can be found in pdf format on the brca website, not timing limitations are mentioned except for 27 turn turn motors which have to have a fixed 24 degrees of timing.

raving-monkey 04-23-2004 10:20 AM

well if you are allowed to change it why put the little tab in there in the first place?


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