Go Back  R/C Tech Forums > General Forums > Electric On-Road
RevTech 17.5 Bad Motor???? >

RevTech 17.5 Bad Motor????

Community
Wiki Posts
Search

RevTech 17.5 Bad Motor????

Thread Tools
 
Search this Thread
 
Old 12-12-2011, 07:29 AM
  #76  
Tech Elite
iTrader: (75)
 
oeoeo327's Avatar
 
Join Date: Oct 2008
Posts: 3,657
Trader Rating: 75 (100%+)
Default

Originally Posted by rx7ttlm
It's trig aka college math 112, Sine of theta will give you a workable answer but since your actually measuring from two points on the circumference the sine function is not actually accurate. When I finish calc 2 next term i will give you the right answer or if I come up with it sooner lol. Right now your finding the angle from the origin to cos Theta, which is not on the outer diameter like what your actually trying to find.
The minute difference of using the arc length (.1954) vs. the measured length (.195) between the 4 marks won't alter the answer significantly enough for it to matter in this case. Imprecise manufacturing tolerances will see to it that the marks aren't EXACTLY 4 degrees apart, making each mark nothing more than a general reference point. However, using the measurements we've obtained, we can use 4 degrees per mark as a guideline for setting the timing.

As for the recent findings with connections shorting out, I've seen several of the accounts firsthand, and can confirm that the solutions that were employed did resolve each problem. However, I think the manufacturer really needs to tighten their quality control standards, as quite a few of these motors are found to have some fault that leads to a premature failure or a non-working unit right out of the box. End users should not have to repair their motors before the first time they are used, and the installation process shouldn't weaken the internal solder joints enough to cause a potential failure.
oeoeo327 is offline  
Old 12-12-2011, 10:29 AM
  #77  
Tech Master
iTrader: (1)
 
spurcheck's Avatar
 
Join Date: Feb 2006
Location: Last in the "Z" main
Posts: 1,642
Trader Rating: 1 (100%+)
Default

Originally Posted by nitrobeast
That's a great idea!!
Man Rui,

you guys are all over these forums. I did not know anyone locally had posted and/or responded on this thread until after I posted my initial comments. Afterward I went and read all the posts and realized several of the "Horsham Crew" had already been "up in here"

I have not actually raced the motor after our findings, so to a degree "the acid test" has not occured yet, but at least at this point the thing runs and that's light years ahead of what I had before. I think I will attempt to forward our findings to Trinity in hopes it might help them assist any other racer who might encounter similar difficultiies. Maybe they could instruct anyone who has the same problem to try what we did, it might save sending a motor back and Trinity having to send one out.
spurcheck is offline  
Old 03-08-2012, 12:04 PM
  #78  
Tech Fanatic
iTrader: (5)
 
Join Date: Nov 2010
Posts: 972
Trader Rating: 5 (100%+)
Default

Originally Posted by EAMotorsports
The center mark is 30 degrees. So two past that would be +16 degrees. So 46 degrees of timing.

P.S. I am still waiting for confirmation that each notch is 8 degrees.

EA
Anyone ever able to get confirmation on this? My best guess was 6 degrees per notch.
Steve S is offline  
Old 03-09-2012, 06:19 AM
  #79  
Tech Addict
iTrader: (8)
 
Join Date: Apr 2011
Location: Marietta, GA
Posts: 587
Trader Rating: 8 (100%+)
Default ?

I just bought a 17.5 yesterday and noticed while installing it that one of the solder tabs is a little loose. Anyone think this will cause a problem? I finished installing it and it works but I'm concerned about the longevity of the motor now.
rcgerber is offline  
Old 03-09-2012, 06:51 AM
  #80  
Tech Elite
iTrader: (15)
 
M-Technic's Avatar
 
Join Date: Sep 2007
Location: Palm Beach, FL
Posts: 2,562
Trader Rating: 15 (100%+)
Default

Originally Posted by Steve S
Anyone ever able to get confirmation on this? My best guess was 6 degrees per notch.
I have it straight from Trinity that it's 8* per tick.
M-Technic is offline  
Old 03-09-2012, 06:56 AM
  #81  
Tech Elite
iTrader: (5)
 
Bishop's Avatar
 
Join Date: May 2004
Location: Brisbane
Posts: 2,223
Trader Rating: 5 (100%+)
Default

Wait, wtf was that bit about burning out a motor being under geared?, I knew they had a sweet spot, but damn, just when you think your getting your head around something, another bit of info drops into your lap...
Bishop is offline  
Old 03-09-2012, 09:57 AM
  #82  
Tech Addict
iTrader: (8)
 
Join Date: Apr 2011
Location: Marietta, GA
Posts: 587
Trader Rating: 8 (100%+)
Default

Originally Posted by rcgerber
I just bought a 17.5 yesterday and noticed while installing it that one of the solder tabs is a little loose. Anyone think this will cause a problem? I finished installing it and it works but I'm concerned about the longevity of the motor now.
Nobodies experienced this with one of these Revtech motors?
rcgerber is offline  
Old 03-09-2012, 11:57 AM
  #83  
Tech Elite
iTrader: (6)
 
Johnny Wishbone's Avatar
 
Join Date: Feb 2006
Posts: 3,762
Trader Rating: 6 (100%+)
Default

Originally Posted by rcgerber
Nobodies experienced this with one of these Revtech motors?
Jim Dieter suggests if the tabs are loose to try to bend them over the board slightly with a pair of pliers. If they are too loose and you have a crash they could short and cause problems.

If you cant bend them, maybe a dab of glue after you solder it up just to keep it from the chance of shorting.
Johnny Wishbone is offline  
Old 03-09-2012, 01:20 PM
  #84  
Tech Addict
iTrader: (8)
 
Join Date: Apr 2011
Location: Marietta, GA
Posts: 587
Trader Rating: 8 (100%+)
Default

Originally Posted by Johnny Wishbone
Jim Dieter suggests if the tabs are loose to try to bend them over the board slightly with a pair of pliers. If they are too loose and you have a crash they could short and cause problems.

If you cant bend them, maybe a dab of glue after you solder it up just to keep it from the chance of shorting.
Thanks for the response. It's funny one of the locals said not to bend the tab so I guess it's a preference. I think the glue option might be the way to go. I was definitely wearily of leaving it as is since I still will tag the wall on occasion.
rcgerber is offline  
Old 03-09-2012, 04:19 PM
  #85  
Tech Elite
iTrader: (6)
 
Johnny Wishbone's Avatar
 
Join Date: Feb 2006
Posts: 3,762
Trader Rating: 6 (100%+)
Default

Originally Posted by rcgerber
Thanks for the response. It's funny one of the locals said not to bend the tab so I guess it's a preference. I think the glue option might be the way to go. I was definitely wearily of leaving it as is since I still will tag the wall on occasion.
Some times even the weight of the speed controls wires are enough to move the terminals on impact. I either read it or Dieter told me to do the tab deal, so I'd think thats pretty gospel. The tough part is finding the right pliers to make it happen as those tabs are pretty thick.
Johnny Wishbone is offline  
Old 03-13-2012, 05:42 PM
  #86  
Tech Master
iTrader: (3)
 
Buckaroo's Avatar
 
Join Date: Oct 2010
Location: Virginia Beach, VA
Posts: 1,576
Trader Rating: 3 (100%+)
Default

Careful with what glue you use. If you use CA, when it cures, it fumes. Even the thin deposit from fuming is conductive! NOT a good thing to have near your motor power posts.
Buckaroo is offline  
Old 03-13-2012, 07:31 PM
  #87  
Tech Elite
iTrader: (6)
 
Johnny Wishbone's Avatar
 
Join Date: Feb 2006
Posts: 3,762
Trader Rating: 6 (100%+)
Default

Originally Posted by Buckaroo
Careful with what glue you use. If you use CA, when it cures, it fumes. Even the thin deposit from fuming is conductive! NOT a good thing to have near your motor power posts.
Yes, for sure, I should have specified not to use a CA, perhaps a epoxy would be much better, no fumes then.
Johnny Wishbone is offline  
Old 03-14-2012, 06:34 AM
  #88  
Tech Regular
iTrader: (8)
 
briankstan's Avatar
 
Join Date: Oct 2008
Location: Utah
Posts: 274
Trader Rating: 8 (100%+)
Default

I picked up a 17.5 revtech for my Touring Car, where should I be starting with the gearing and timing?

Class is 17.5 blinky, Rubber tires on Medium bite carpet. I'm running 64p gears with a 96 spur.
briankstan is offline  
Old 03-14-2012, 07:08 AM
  #89  
Team EAM
iTrader: (79)
 
Join Date: Dec 2001
Location: Murfreesboro, TN
Posts: 9,701
Trader Rating: 79 (100%+)
Default

Originally Posted by briankstan
I picked up a 17.5 revtech for my Touring Car, where should I be starting with the gearing and timing?

Class is 17.5 blinky, Rubber tires on Medium bite carpet. I'm running 64p gears with a 96 spur.
Last notch of timing and probably a 46 pinion to start with depending on track size.

EA
EAMotorsports is offline  
Old 03-14-2012, 07:10 AM
  #90  
Tech Master
iTrader: (1)
 
locked's Avatar
 
Join Date: Mar 2010
Location: Toronto
Posts: 1,758
Trader Rating: 1 (100%+)
Default

Originally Posted by briankstan
I picked up a 17.5 revtech for my Touring Car, where should I be starting with the gearing and timing?

Class is 17.5 blinky, Rubber tires on Medium bite carpet. I'm running 64p gears with a 96 spur.
You should include track size. Brand of car would also help if you are looking for someone to tell you which pinion to use with your 96 spur, instead of just the FDR. They have different internal ratios.

4.0 FDR is a reasonable starting point for a medium sized track. Lower for larger tracks.

Can timing...Crank it up, but check temps often, use a fan and make sure your drivetrain is as free as it can be.
locked is offline  


Contact Us - Archive - Advertising - Cookie Policy - Privacy Statement - Terms of Service -

Copyright © 2024 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.