R/C Tech Forums

Go Back   R/C Tech Forums > General Forums > Micro and Mini Scales

Reply
 
Thread Tools Search this Thread
Old 02-12-2010, 04:28 PM   #1
Tech Adept
 
Heavy-D's Avatar
 
Join Date: Nov 2009
Location: New Jersey
Posts: 107
Default Losi micro t problem

I just bought a losi micro t today. i took it out of the box charged it and ran it the first time it ran great. Second time around it ran good. After then the run times have been getting shorter and shorter. Some white smoke was coming from the brushed motor at one point. The motor gets really hot really fast and the car stops working. Im going to assume this is because of some temp cutoff thats built into the ESC. But there is no reason it should charge for about 20 min and then run for less then 30 seconds. Anybody else experience this? or something like it? I am going to take it back to my LHS asap where i bought it from because im pretty sure its broken but i wanted to see what i could find out on here.
__________________
Traxxas Rustler VXL
Team Losi Micro-T
Team Losi XXX-NT Sport
Heavy-D is offline   Reply With Quote
Old 02-14-2010, 02:12 AM   #2
Tech Master
 
JatoTheRipper's Avatar
 
Join Date: Sep 2007
Location: PA
Posts: 1,394
Trader Rating: 3 (100%+)
Default

Quote:
Originally Posted by Heavy-D View Post
I just bought a losi micro t today. i took it out of the box charged it and ran it the first time it ran great. Second time around it ran good. After then the run times have been getting shorter and shorter. Some white smoke was coming from the brushed motor at one point. The motor gets really hot really fast and the car stops working. Im going to assume this is because of some temp cutoff thats built into the ESC. But there is no reason it should charge for about 20 min and then run for less then 30 seconds. Anybody else experience this? or something like it? I am going to take it back to my LHS asap where i bought it from because im pretty sure its broken but i wanted to see what i could find out on here.
Because the Micro-Ts are made in China the build quality is very poor. Most Micro-Ts come from the factory with the transmission screws way too tight. This basically binds the transmission gears and puts a lot of drag on the drivetrain. This could definitely be making your motor get hot.

What you have to do is back off the screws that hold the transmission together. I think there are three (3) of them. It's best to take the motor off so that you can feel how much drag is on the transmission. There should be virtually none without the motor installed.
JatoTheRipper is offline   Reply With Quote
Old 02-14-2010, 06:52 PM   #3
Tech Adept
 
Heavy-D's Avatar
 
Join Date: Nov 2009
Location: New Jersey
Posts: 107
Default

Quote:
Originally Posted by JatoTheRipper View Post
Because the Micro-Ts are made in China the build quality is very poor. Most Micro-Ts come from the factory with the transmission screws way too tight. This basically binds the transmission gears and puts a lot of drag on the drivetrain. This could definitely be making your motor get hot.

What you have to do is back off the screws that hold the transmission together. I think there are three (3) of them. It's best to take the motor off so that you can feel how much drag is on the transmission. There should be virtually none without the motor installed.
What you explained about the drag makes perfect sense with the motor attached but if i move the motor away from the pinion gear there is barely any drag which brings me back to it being a motor problem i think. I'm going to bring it back to my LHS and explain my problem and see if they can do anything for me considering i bought it from them and had problems out of the box. Should i consider replacing the motor?
__________________
Traxxas Rustler VXL
Team Losi Micro-T
Team Losi XXX-NT Sport
Heavy-D is offline   Reply With Quote
Old 02-14-2010, 07:04 PM   #4
Tech Master
 
JatoTheRipper's Avatar
 
Join Date: Sep 2007
Location: PA
Posts: 1,394
Trader Rating: 3 (100%+)
Default

Quote:
Originally Posted by Heavy-D View Post
What you explained about the drag makes perfect sense with the motor attached but if i move the motor away from the pinion gear there is barely any drag which brings me back to it being a motor problem i think. I'm going to bring it back to my LHS and explain my problem and see if they can do anything for me considering i bought it from them and had problems out of the box. Should i consider replacing the motor?
Definitely take it back and see if the LHS stands good for it. If they won't rectify the situation, don't ever go back to them and let them know they lost you as a customer. If they do help you out let them know you appreciate and will be back when you need to buy something.

The spur to pinion mesh could have been too tight from the factory as well. That would also cause a sever drag on the motor. I forgot to mention that spur to pinion mesh is so critical on these things as well.

If you decide to buy a new motor go for the Atomic BBII motor. It's a ball bearing replacement motor that is also faster. And it's only $15 online.
JatoTheRipper is offline   Reply With Quote
Old 02-14-2010, 08:13 PM   #5
Tech Adept
 
Heavy-D's Avatar
 
Join Date: Nov 2009
Location: New Jersey
Posts: 107
Default

Quote:
Originally Posted by JatoTheRipper View Post
Definitely take it back and see if the LHS stands good for it. If they won't rectify the situation, don't ever go back to them and let them know they lost you as a customer. If they do help you out let them know you appreciate and will be back when you need to buy something.

The spur to pinion mesh could have been too tight from the factory as well. That would also cause a sever drag on the motor. I forgot to mention that spur to pinion mesh is so critical on these things as well.

If you decide to buy a new motor go for the Atomic BBII motor. It's a ball bearing replacement motor that is also faster. And it's only $15 online.
I bought the atomic BBII motor anyways and i double checked the pinion and spur and the diff. There is one part in the diff that the best way i can think to describe it is its like a kink in the diff. Its small and barely takes any pressure to get past it but what feels like no pressure to me could be stressing the motor. Maybe the diff just hasent broken in yet im not really sure. There are too many different possibilities it can be. I am going to hope my LHS is good to at least attempt to fix my problem especially since this is a constant out if the box problem from what i have heard. Hes a pretty good guy and i dont see why he would not help me out. If worst comes to worse ill just see about rebuilding the whole diff with aluminum parts because i was going to swap the whole car to that anyways.
__________________
Traxxas Rustler VXL
Team Losi Micro-T
Team Losi XXX-NT Sport
Heavy-D is offline   Reply With Quote
Old 02-15-2010, 04:27 PM   #6
Tech Master
 
JatoTheRipper's Avatar
 
Join Date: Sep 2007
Location: PA
Posts: 1,394
Trader Rating: 3 (100%+)
Default

Quote:
Originally Posted by Heavy-D View Post
I bought the atomic BBII motor anyways and i double checked the pinion and spur and the diff. There is one part in the diff that the best way i can think to describe it is its like a kink in the diff. Its small and barely takes any pressure to get past it but what feels like no pressure to me could be stressing the motor. Maybe the diff just hasent broken in yet im not really sure. There are too many different possibilities it can be. I am going to hope my LHS is good to at least attempt to fix my problem especially since this is a constant out if the box problem from what i have heard. Hes a pretty good guy and i dont see why he would not help me out. If worst comes to worse ill just see about rebuilding the whole diff with aluminum parts because i was going to swap the whole car to that anyways.
A lot of people break the diff in by holding one wheel while holding the throttle for something like 20 seconds. Then hold the other wheel and repeat the process.

I'm not sure what you mean by a "kink" in the diff. Have you taken it apart to inspect the gears? I'd do this only after taking it to the LHS to get them to solve it first. If they don't help, call Losi/Horizon Hobby. They have the absolute best customer service and they might send you out a replacement differential.

Cool. Let me know how you like the Atomic BBII. Make sure that's not installed when you take it back to the LHS.

Currently, there are no metal gears for the Micro-T so the only aluminum piece you can get is the transmission case. And you have to buy shims to use with the aluminum transmission or else your diff will strip. Whoever designed it didn't spec it out right and there's too much play in the transmission. Shoddy Chinese "engineer" at it's best. Chinese engineering...now there's an oxymoron!
JatoTheRipper is offline   Reply With Quote
Old 02-15-2010, 08:24 PM   #7
Tech Adept
 
Heavy-D's Avatar
 
Join Date: Nov 2009
Location: New Jersey
Posts: 107
Default

Quote:
Originally Posted by JatoTheRipper View Post
A lot of people break the diff in by holding one wheel while holding the throttle for something like 20 seconds. Then hold the other wheel and repeat the process.

I'm not sure what you mean by a "kink" in the diff. Have you taken it apart to inspect the gears? I'd do this only after taking it to the LHS to get them to solve it first. If they don't help, call Losi/Horizon Hobby. They have the absolute best customer service and they might send you out a replacement differential.

Cool. Let me know how you like the Atomic BBII. Make sure that's not installed when you take it back to the LHS.

Currently, there are no metal gears for the Micro-T so the only aluminum piece you can get is the transmission case. And you have to buy shims to use with the aluminum transmission or else your diff will strip. Whoever designed it didn't spec it out right and there's too much play in the transmission. Shoddy Chinese "engineer" at it's best. Chinese engineering...now there's an oxymoron!


So this is what i have decided to do because I emailed Losi and their customer service is going to send me a new motor because im pretty sure i blew the motor, it only works sometimes, makes funny noises, and works better in reverse then forward lol. Im not sure about the diff cause I have not opened it up to check the diff yet but i will and im going to replace the gears inside the diff. Then im gonna use the new motor that Losi is sending me to make sure everythings okay and once it is ill put the Atomic BBII in. Thats what i have figured out so far.

and the best way to explain the kink is if i grab both the tires and turn them forward there is a spot that i get to that is almost like a snag. One spot thats harder to turn the tires and then it gets past it and goes back to normal. So its almost like one tooth on the gears inside the diff is messed up and everytime it gets to that tooth its causing stress on the motor.
__________________
Traxxas Rustler VXL
Team Losi Micro-T
Team Losi XXX-NT Sport
Heavy-D is offline   Reply With Quote
Old 02-15-2010, 09:48 PM   #8
Tech Master
 
JatoTheRipper's Avatar
 
Join Date: Sep 2007
Location: PA
Posts: 1,394
Trader Rating: 3 (100%+)
Default

Quote:
Originally Posted by Heavy-D View Post
So this is what i have decided to do because I emailed Losi and their customer service is going to send me a new motor because im pretty sure i blew the motor, it only works sometimes, makes funny noises, and works better in reverse then forward lol. Im not sure about the diff cause I have not opened it up to check the diff yet but i will and im going to replace the gears inside the diff. Then im gonna use the new motor that Losi is sending me to make sure everythings okay and once it is ill put the Atomic BBII in. Thats what i have figured out so far.

and the best way to explain the kink is if i grab both the tires and turn them forward there is a spot that i get to that is almost like a snag. One spot thats harder to turn the tires and then it gets past it and goes back to normal. So its almost like one tooth on the gears inside the diff is messed up and everytime it gets to that tooth its causing stress on the motor.
Did you also tell Losi about the binding in your diff? If not, you should have.

But didn't I tell you Losi customer service was great? Most other companies don't even respond to email!

I definitely understand what you mean by a snag in the diff. Mine was like that as well. I blew out my diff when I switched to the aluminum transmission without shimming it so I glued the gears together and now have a locked diff. So I can't tell you if I would still have a snag or if it would have gone away after the break-in of the differential.

Interestingly, my cousin bought a Micro-B and his diff was perfect from the factory! It was a little tight, but ran fine. My diff was so tight from the factory that the motor couldn't even spin the diff when on the ground! My cousin's is, and always was faster than mine. And his always did wheelies where mine would only ever do them after the diff broke in and the battery was fully charged. Even then, sometimes only a quick reverse to forward action on the controller would make it wheelie.
JatoTheRipper is offline   Reply With Quote
Old 02-16-2010, 06:28 AM   #9
Tech Adept
 
Heavy-D's Avatar
 
Join Date: Nov 2009
Location: New Jersey
Posts: 107
Default

Quote:
Originally Posted by JatoTheRipper View Post
Did you also tell Losi about the binding in your diff? If not, you should have.

But didn't I tell you Losi customer service was great? Most other companies don't even respond to email!

I definitely understand what you mean by a snag in the diff. Mine was like that as well. I blew out my diff when I switched to the aluminum transmission without shimming it so I glued the gears together and now have a locked diff. So I can't tell you if I would still have a snag or if it would have gone away after the break-in of the differential.

Interestingly, my cousin bought a Micro-B and his diff was perfect from the factory! It was a little tight, but ran fine. My diff was so tight from the factory that the motor couldn't even spin the diff when on the ground! My cousin's is, and always was faster than mine. And his always did wheelies where mine would only ever do them after the diff broke in and the battery was fully charged. Even then, sometimes only a quick reverse to forward action on the controller would make it wheelie.

I sent them the email way before i ever decided to look into the problem and figure it out myself so i am just gonna rebuild the diff my way with my own parts and hope that works. I guess the car is just so small that they cant get the diff perfect every time or something. Quite a shame tho that the cars arent manufactured better because it seems like a lot of people who dont know anything about RC would pick one of these up to have some fun with and would be much more upset then someone who could figure this out.
__________________
Traxxas Rustler VXL
Team Losi Micro-T
Team Losi XXX-NT Sport
Heavy-D is offline   Reply With Quote
Sponsored Links
Reply


Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts
BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are Off

Similar Threads
Thread Thread Starter Forum Replies Last Post
Losi micro T - official thread Djioul Micro and Mini Scales 82 10-31-2013 02:22 PM
Team Losi Micro T estermann Singapore R/C Racers 24 07-28-2008 05:03 AM


All times are GMT -8. It is currently 02:19 AM.



SEO by vBSEO 3.5.0