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Old 02-18-2013, 09:32 AM   #16
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Personally, I wouldn't feel comfortable pushing my revtech to +160°F on a regular basis. I ran almost full static timing with it this weekend and it certainly gave me more punch in the beginning, but it faded significantly. Max timing is too much for the revtech IMO and from my experience 3-4 timing marks is where to be for club racing.
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Old 02-18-2013, 09:41 AM   #17
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Originally Posted by cyanyde View Post
OT: This is exactly the reason why blinky is losing popularity here... Blinky was meant to narrow the playing field and keep costs down but racers actually spent more in search of the fastest motors/setup and blowing a few along the way...

Go Turbo! Hehehe...
I agree with you about pushing the limits of the spec class but everyone on the east coast is doing it and if you want to be competitive you have no choice. IMO
We as racers are always stiving for speed no matter what class...If we didnt it wouldn't be normal.

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Personally, I wouldn't feel comfortable pushing my revtech to +160°F on a regular basis. I ran almost full static timing with it this weekend and it certainly gave me more punch in the beginning, but it faded significantly. Max timing is too much for the revtech IMO and from my experience 3-4 timing marks is where to be for club racing.
After installing the new fan from Side piece I was temping in the low hundreds. I was actually shocked what a difference it made. Take a chance on what I say the fan is like 12-15 dollars and they ship to canada. Great acceleration and top end is what experience now!!
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Old 02-18-2013, 09:49 AM   #18
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Default My thoughts on the Revtech Motors

I think in general we are pushing the motors way too hard in the Blinky Classes looking for speed. The Fans are actually aiding in this process more than helping. Do the fans help... Yes, but you really need to setup, gear and tune your motor without the fan FIRST! Otherwise you do not get a good baseline. You have to remember that even with a good fan blowing on the motor the core temps inside the stator are still going to get out of control right at critical areas in the stator due to the amp draw we are pulling.

The Revtechs are a crazy fast motor but many are over gearing them and then putting way to much timing on top of way to much gear... They then burn up. You just can't gear the Revtech motors like you can the D3 or D3.5s.

Even if they let go at only 130 degrees with a fan blowing on them it is most likely that they have been ran too hard to many times. Yes a good fan will reduce temps by 30 degrees when & where we take a temp measurement... but if you are pushing the motor to 150 or 160 with fan on it then most likely core temps are still almost the same as running them to 180+ every time.

Best Practice with any motor brand:

1. Reduce time and work on base gearing the motor is happy with where it pulls good off corner and for most of the straight, confirm temps are in the 140s... (No FAN)

2. Adjust timing for stronger pull off corner and for more top end down the straights. Confirm temps are in acceptable range 150s to 170s with again NO FAN. You may have to go up or down a tooth to find this sweet spot when playing with timing. Most often you may have to drop a tooth to run close to max timing but there is a point where the amp draw will almost double with just a little more timing and the motor will run stupid hot no matter what… Then we drop down a few teeth thinking it is what the motor wants, yes it will be fast but it will run hot… Too much timing!
Personally with the Revtechs, you can run them almost to the plus sign on the can with gearing just right! But any further and they will run stupid hot all the time! BUT work up to this point with gearing and testing… DO NOT JUST CRANK UP TIMING AND START THERE!

3. Add fan to keep motor temps lower and motor more consistent for entire run with end temps around 150s with Fan.

Only at a larger race would I intentionally push the limits.
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Old 02-18-2013, 10:29 AM   #19
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I run fans for the sake of performance, the car fades a lot less with fans on the motor.
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Old 02-18-2013, 12:38 PM   #20
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Unfortunately, that's not the first time I've seen something like this happen. While it's probably a somewhat random occurrence, I've seen a few of these motors short out and melt down after a few minutes on the track. Personally, I've melted down 2 Revtech 17.5s at 140 degrees, and witnessed a fellow racer's Revtech motor fail at 100 degrees after 3 laps. These motors run strong, but the risk of premature motor failure led me to switch motor manufacturers after two of them went up in smoke at "normal" operating temperatures.
This was me.
Motor was new and only had three runs on it (never near/above 160) timing at the last hash mark.....Blinky.
Stator had the epoxy a burnt off of one winding...but the rest of the wire looks brand new (ZERO tarnish or color change).
What was strange was the windings looked mushroomed off the stator plates (no..it was not free spun).I checked the esc wires to look for a loose strand...but everything checked out.
Looks to me like a bad wind job or some sort of internal short. I will post up a pic. later today.
Budget racer here...it hurts bad.
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Old 02-18-2013, 08:42 PM   #21
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Obviously trinity never redesigned the stator to take the extra timing. Wish I could still run my D3.5 but time to try a different 17.5.
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Old 02-19-2013, 07:05 AM   #22
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Pics.
Don't mind the little black foam dots...I had a truer malfunction when packing up my gear
As you can see from the other winds it was not overheated....strange.
Attached Thumbnails
Revtech 17.5 melting down-burnt.jpg   Revtech 17.5 melting down-bottom.jpg   Revtech 17.5 melting down-side.jpg  
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Old 02-19-2013, 07:16 PM   #23
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I'm trying a Revtech for the first time. Had to give up my D3.5 cause our track no longer allows them. I loved that motor! I even dremeled out timming to reach 40 degrees on that thing. Basically I was trying to kill it and it wouldnt die. I ran a HT rotor and max 40degree timming with a fan and temps were comming off at 150 ish. I dont care what people were saying that you didnt have to dremel out endbell cause there was timming already built in. That motor was the best! I dont plan on tweeking my Revtech, but so far its a good one! Keep hearing that Trinity is releasing a stator to replace the D3.5 roar legal! I dont know for sure! I hope that Trinity redeems themselfs and maybe they will let us trade our stators back in for a new legal one.
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Old 02-19-2013, 08:04 PM   #24
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Quote:
Originally Posted by j.d.roost View Post
Pics.
Don't mind the little black foam dots...I had a truer malfunction when packing up my gear
As you can see from the other winds it was not overheated....strange.
Thats what both mine look like inside
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Old 02-19-2013, 08:05 PM   #25
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Originally Posted by JFuel11 View Post
I think in general we are pushing the motors way too hard in the Blinky Classes looking for speed. ....if you are pushing the motor to 150 or 160 with fan on it then most likely core temps are still almost the same as running them to 180+ every time.
Best Practice with any motor brand:....
.
What do you think of the idea of asking the speed control manufacturers to providing a timing advance variation with rpm. (you know like the centrifugal advance in all distributors in the '50's - '60's had, IE:like all TransAm competitors used!!)

who knows? it just might be more efficient, and the motor might run cooler, and be less sensitive to battery voltage?
Dare to Dream!
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Old 02-19-2013, 08:11 PM   #26
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Thats what both mine look like inside
Yep...sort of crappy I guess.
I am still running one as they are very fast...hoping I just got a bad wind.
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Old 02-19-2013, 09:14 PM   #27
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Default smoke

Guys,
It really is pretty simple: Press the timing, or press the gearing. Press both = smoke. Blinky may have equalized performance, but maximized expense (to figure-out maximum performance).
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