Official Losi Micro SCT/Rally/Truggy Thread
03-12-2012, 06:42 PM
#391
Tech Rookie
Hi All,
I just received my brushless rally car to go along with my 2yr old brush rally car. Boy it's AWESOME!!! BUT I have had a few problems already:
I have an RCP on-road track so I took all my shocks off and changed the oil weight to 75. When I put the shocks back on I re-mounted them as low as possible for lower center of gravity. Then I did the mod to increase the turning radius...same setup as my brushed car.
On a funny note, on full throttle with a Lipo it will do a wheelie and the Lexan body with scrape. When I hit the brakes the the rear wheels will go into the air and the front of the body will scrape. I thought the 75 weight oil would resolve this.....it might have lessened this BUT it still happens so I just trimmed the back and front of the bodies a little bit.
On a side note- I noticed right out of the box the drivetrain had SOOOO much less drag than my old brushed car....still trying to figure out why. My diffs feel fine in the old car, maybe my gear mesh is too tight? Like someone posted earlier, my brush car feels like drag brake is always on! It probably makes it easier to drive BUT the motor gets soooo hot.
Anyway, the next day I noticed my front shocks were leaking....so I took them back apart, refilled them and then......noticed they kept leaking from the bottom seals.....called Horizon today and they are sending me out 4 new ones.
For now, I stole the shocks off my brushed car....and everything was fine.....until......the grinding started and then zeeeeeeee.....car was barley moving and it sounded like the gears weren't playing nice.
So, I took the top cover off and looked inside, the spur gear was getting cut-down to size by the stock brass pinion!! Yikes, now when I called Horizon about the shocks I told them about this and they said as a curtsey they would also spend me out another spur gear!!!
Now, I tried to re-mesh the gears with not such a great success. If it was too tight the car would spin out when I let off the throttle. I tried to loosen it but now I have a sort of strange problem: I can give it very little throttle and hear the motor want to go BUT the wheels won't turn? (This is with the car turned upside down of course). The battery was almost dead so I will try tonight and see if it still does this.
Here is another important question:
When I ripped apart the car to try and "fix" the gear mesh I noticed that the brass pinion was all the way at the end of the motor shaft. It would mesh with the spur but only the rear portion of the brass gear was touching the spur. So in this configuration it appears that the motor shaft is being side loaded. This just doesn't look correct to me or good for the motor. Usually, when one gear is wider than the other, the gears are centered when meshed. Is this normal or has my brass pinon shifted to the end of the shaft?
If no one knows what I am talking about I could take a pic and post.
I just received my brushless rally car to go along with my 2yr old brush rally car. Boy it's AWESOME!!! BUT I have had a few problems already:
I have an RCP on-road track so I took all my shocks off and changed the oil weight to 75. When I put the shocks back on I re-mounted them as low as possible for lower center of gravity. Then I did the mod to increase the turning radius...same setup as my brushed car.
On a funny note, on full throttle with a Lipo it will do a wheelie and the Lexan body with scrape. When I hit the brakes the the rear wheels will go into the air and the front of the body will scrape. I thought the 75 weight oil would resolve this.....it might have lessened this BUT it still happens so I just trimmed the back and front of the bodies a little bit.
On a side note- I noticed right out of the box the drivetrain had SOOOO much less drag than my old brushed car....still trying to figure out why. My diffs feel fine in the old car, maybe my gear mesh is too tight? Like someone posted earlier, my brush car feels like drag brake is always on! It probably makes it easier to drive BUT the motor gets soooo hot.
Anyway, the next day I noticed my front shocks were leaking....so I took them back apart, refilled them and then......noticed they kept leaking from the bottom seals.....called Horizon today and they are sending me out 4 new ones.
For now, I stole the shocks off my brushed car....and everything was fine.....until......the grinding started and then zeeeeeeee.....car was barley moving and it sounded like the gears weren't playing nice.
So, I took the top cover off and looked inside, the spur gear was getting cut-down to size by the stock brass pinion!! Yikes, now when I called Horizon about the shocks I told them about this and they said as a curtsey they would also spend me out another spur gear!!!
Now, I tried to re-mesh the gears with not such a great success. If it was too tight the car would spin out when I let off the throttle. I tried to loosen it but now I have a sort of strange problem: I can give it very little throttle and hear the motor want to go BUT the wheels won't turn? (This is with the car turned upside down of course). The battery was almost dead so I will try tonight and see if it still does this.
Here is another important question:
When I ripped apart the car to try and "fix" the gear mesh I noticed that the brass pinion was all the way at the end of the motor shaft. It would mesh with the spur but only the rear portion of the brass gear was touching the spur. So in this configuration it appears that the motor shaft is being side loaded. This just doesn't look correct to me or good for the motor. Usually, when one gear is wider than the other, the gears are centered when meshed. Is this normal or has my brass pinon shifted to the end of the shaft?
If no one knows what I am talking about I could take a pic and post.
03-12-2012, 08:44 PM
#392
Tech Rookie
FIGURED IT OUT!!!
Looks like I will be calling Horizon again tomorrow 
So, the gear mesh thing has just been bothering me all day. After I wrote the above post, I decided to go back and investigate. My first thought was that the brass pinion could be pushed back more on the motor shaft.
This time when I took apart the car I actually took the motor completely out. That is when I noticed that the shaft of the motor had rubbed against the chassis wall a bit. Then I looked more closely at the motor AND realized the motor shaft of my new brushless motor can move at least 1/4" forward from the can!!! This is what had actually happened last night. The motor mount didn't shift backward like I thought, the shaft of the motor, complete with pinion, had moved forward!!!
Has anyone ever heard of this failure?
So, the gear mesh thing has just been bothering me all day. After I wrote the above post, I decided to go back and investigate. My first thought was that the brass pinion could be pushed back more on the motor shaft.
This time when I took apart the car I actually took the motor completely out. That is when I noticed that the shaft of the motor had rubbed against the chassis wall a bit. Then I looked more closely at the motor AND realized the motor shaft of my new brushless motor can move at least 1/4" forward from the can!!! This is what had actually happened last night. The motor mount didn't shift backward like I thought, the shaft of the motor, complete with pinion, had moved forward!!!
Has anyone ever heard of this failure?
03-13-2012, 12:59 AM
#393
Yikes! Never heard that about the motor.
The cars are built the same so per the drivetrain moving easier. The brushless motor wont have any magnetic resistance the way its built when you spin the wheels by hand. Thats really the only difference in the drivetrains.
I just modded mine to take a digital servo. Though I couldn't use a servo saver. Its a metal geared servo, so hopefully it will survive!
Per your shocks. Get the stiffer springs to help with this versus relying on your oil. As it is, I think possibly one reason your shocks leaked is your using way too stiff an oil, so there is so much resistance, the oil pushes itself out of the seals. I put 40 in one and its pretty dampened as it is with the stock springs. It might be perfect though with the harder springs.
Remember this car is ultra light for a 1/24th so it wont need to take much oil weights as other vehicles.
The cars are built the same so per the drivetrain moving easier. The brushless motor wont have any magnetic resistance the way its built when you spin the wheels by hand. Thats really the only difference in the drivetrains.
I just modded mine to take a digital servo. Though I couldn't use a servo saver. Its a metal geared servo, so hopefully it will survive!
Per your shocks. Get the stiffer springs to help with this versus relying on your oil. As it is, I think possibly one reason your shocks leaked is your using way too stiff an oil, so there is so much resistance, the oil pushes itself out of the seals. I put 40 in one and its pretty dampened as it is with the stock springs. It might be perfect though with the harder springs.
Remember this car is ultra light for a 1/24th so it wont need to take much oil weights as other vehicles.
03-13-2012, 12:38 PM
#394
Tech Rookie
Called Horizon today and I just can't believe how good their customer service is. They are sending me a new motor, no questions asked.
About the oil weight, what is it stock? I am using 75 weight on my brush car without issue. I think I just got bad shocks.
About the oil weight, what is it stock? I am using 75 weight on my brush car without issue. I think I just got bad shocks.
03-13-2012, 02:30 PM
#395
I dunno. 25?
03-14-2012, 01:14 PM
#396
Just bought a Hyperion 25c 240mah lipo. Same width as the stock battery but about 1/2 inch shorter. Just charging at the moment. It'll be in a brushless rally I got yesterday. I have a business and got a floor with martial arts interlocking mats. The dimensions are 24x16 feet. I think I'm going to get some 1" pvc pipe and make me a removable track
03-14-2012, 03:38 PM
#397
Too fast on the 240mah lipo 2s 25c. Willie on the gas. I am traction rolling in the martial arts mat. Any suggestions like should I stiffen up the suspension a bit?
03-14-2012, 04:23 PM
#398
Looks like I will be calling Horizon again tomorrow
So, the gear mesh thing has just been bothering me all day. After I wrote the above post, I decided to go back and investigate. My first thought was that the brass pinion could be pushed back more on the motor shaft.
This time when I took apart the car I actually took the motor completely out. That is when I noticed that the shaft of the motor had rubbed against the chassis wall a bit. Then I looked more closely at the motor AND realized the motor shaft of my new brushless motor can move at least 1/4" forward from the can!!! This is what had actually happened last night. The motor mount didn't shift backward like I thought, the shaft of the motor, complete with pinion, had moved forward!!!
Has anyone ever heard of this failure?
So, the gear mesh thing has just been bothering me all day. After I wrote the above post, I decided to go back and investigate. My first thought was that the brass pinion could be pushed back more on the motor shaft.
This time when I took apart the car I actually took the motor completely out. That is when I noticed that the shaft of the motor had rubbed against the chassis wall a bit. Then I looked more closely at the motor AND realized the motor shaft of my new brushless motor can move at least 1/4" forward from the can!!! This is what had actually happened last night. The motor mount didn't shift backward like I thought, the shaft of the motor, complete with pinion, had moved forward!!!
Has anyone ever heard of this failure?
03-14-2012, 09:33 PM
#399
Tech Rookie
hey guys. i'm new on this site but have been on RCUniverse for a while now. i started a Micro SCT thread over there about 6 months ago but it is almost dead. hopefully this one will be more active. i just got 3 2s 350mah 20c Zippy lipos in the mail from hobbbyking the other day. i soldered on the correct plugs on my ESC and this thing flies. its a completely different truck even though its still brushed. i may just wait a while to go BL like i had planned as long as the stock electronics hold up on me. they seem to be getting hot, but i think thats mostly due to a poor design. they can't get hardly any airflow, something that is just ridiculous...
03-22-2012, 06:07 PM
#400
Tech Regular
on losi site there saying the truggy has a longer wheel base
03-22-2012, 06:20 PM
#401
03-22-2012, 06:25 PM
#402
There is always the mini-z buggy...
03-22-2012, 10:09 PM
#403
03-23-2012, 02:32 PM
#404
Gary posted on mtf that its the same lenght and chassis minus the side pegs.
As far as wide track kit goes. I've been talkin with RJ from thetoyz and he said he would let me know in a few Weeks if he was going to make a kit or not.
As far as wide track kit goes. I've been talkin with RJ from thetoyz and he said he would let me know in a few Weeks if he was going to make a kit or not.
04-03-2012, 06:09 PM
#405
Tech Regular
Losi web site says longer wheel base