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Old 02-23-2011, 12:45 AM   #2266
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Typically if your motor is hot and your ESC is cool, you are either undergeared or just going WOT everywhere (like in a parking lot).

As a generalization, if your ESC is cool and the motor is hot, you are undergeared and spending too much time at max RPM.

If the ESC is hot and the motor is cool, you are overgeared and not getting near max RPM.

Typically you want them to be around the same temp.

Of course, there are exceptions to everything (track conditions, size, grip, etc).

For bashing I have no idea.
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Old 02-23-2011, 12:50 AM   #2267
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this was at OCRC; an indoor high grip track.
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Old 02-23-2011, 12:56 AM   #2268
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So if it's racing on a high grip surface (which is what I race my TT on as well) and your motor is screaming hot and your ESC is cool, you are probably undergeared.

When you start overheating your ESC you'll be overgeared.

So look at it this way, lots of heavy braking usually heats up the ESC.

Lots of WOT usually heats up the motor.

You need to adjust your ESC profile and gearing to suit.

With a 550 sized motor, you can probably go up from 16t. For a 1/10th scale motor that would be too tall and would probably smoke the ESC.

Trying going up one tooth at a time, running some laps at race pace, then temp it. You may only need to go up 1 or 2 teeth at the most.
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Old 02-23-2011, 07:02 AM   #2269
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Originally Posted by heavyjeffd View Post
So if it's racing on a high grip surface (which is what I race my TT on as well) and your motor is screaming hot and your ESC is cool, you are probably undergeared.

When you start overheating your ESC you'll be overgeared.

So look at it this way, lots of heavy braking usually heats up the ESC.

Lots of WOT usually heats up the motor.

You need to adjust your ESC profile and gearing to suit.

With a 550 sized motor, you can probably go up from 16t. For a 1/10th scale motor that would be too tall and would probably smoke the ESC.

Trying going up one tooth at a time, running some laps at race pace, then temp it. You may only need to go up 1 or 2 teeth at the most.
when you say go up from 16T, you mean going down in teeth right?
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Old 02-23-2011, 07:18 AM   #2270
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yes go down in teeth i run a novak 550 hv 4.5 and a 12 th pinion never gets hot and is plenty fast find where your motor is staying cool and if you want more speed from there go up one tooth if you look back over the thread couple of people have geared up to 16 tooth and had same heat issues as far as parts breaking just stock up all i have broke is a front hub and a rear arm but the thing is on rails and lap the 4xs by at least 2 laps
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Old 02-23-2011, 07:28 AM   #2271
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when you say go up from 16T, you mean going down in teeth right?
When I was racing mine I was running the Ballistic 550 4.5t on a 13t pinion with a Mamba Max Pro on 2s and it was more than fast on our indoor track. Wheelies on demand through the straights and plenty of fun. Never ran over 115 deg.
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Old 02-23-2011, 07:43 AM   #2272
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when you say go up from 16T, you mean going down in teeth right?
Well if your motor is screaming hot and your ESC is cool, it sounds like you are sitting on max RPM for too long, so it almost sounds like you need to go UP to a bigger pinion (more teeth) to me.

Generally when you have that you are undergeared. Because the motor is just winding out for too long.

But it has a lot to do with the track you are on, if you have tons of places where you are WOT that might effect your gearing. The track I run at doesn't have a lot of WOT (just one spot), it's mostly tight/technical and I run a 1/1th scale ESC.

Your best bet is to just experiment with pinions. Go to an 18t, see what happens after a few laps. Go down to 14t, see what happens.

But in most cases, cold ESC/hot motor means too small a pinion.
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Old 02-23-2011, 07:54 AM   #2273
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Also a lot of it depends on the kV of the motor.

For example, I was running my ebuggy at a track (it's a 1700kV) with a 16t pinion and the motor was hitting 180F but the ESC was not even breaking 90F. It's because it was winding out and sitting at max RPM too long.

I went up to a 22t pinion (experimented going up 2t at a time) and now it comes off on the same track at 110F for speedo and motor after a 10min main.
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Old 02-23-2011, 10:41 AM   #2274
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Originally Posted by heavyjeffd View Post
Well if your motor is screaming hot and your ESC is cool, it sounds like you are sitting on max RPM for too long, so it almost sounds like you need to go UP to a bigger pinion (more teeth) to me.

Generally when you have that you are undergeared. Because the motor is just winding out for too long.

But it has a lot to do with the track you are on, if you have tons of places where you are WOT that might effect your gearing. The track I run at doesn't have a lot of WOT (just one spot), it's mostly tight/technical and I run a 1/1th scale ESC.

Your best bet is to just experiment with pinions. Go to an 18t, see what happens after a few laps. Go down to 14t, see what happens.

But in most cases, cold ESC/hot motor means too small a pinion.
this philosophy used to hold true with brushed motors. not so much with brushless...
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Old 02-23-2011, 10:44 AM   #2275
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Yeah, that's why I suggested that he just experiment with some pinions and see how it turns out.
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Old 02-23-2011, 11:04 AM   #2276
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with a hot esc and cool motor, the battery could also be the culprit.
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Old 02-23-2011, 11:34 AM   #2277
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Maybe a bad battery or the wrong battery.

But as I said these were generalizations, there are exception everything.

By generalizing I was assuming he's using a good battery and the right battery.
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Old 02-23-2011, 11:56 AM   #2278
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with a hot esc and cool motor, the battery could also be the culprit.

This is what Im starting to think and my foams in my stock tires are basically non existent which probably means more tire spin and maxed out RPM. The battery is def still good, I just dont think its enough juice with the ESC being a 120Amp and the battery being rated at 20C-30C. Do both these factors make sense, since last week I ran the same set up but my motor temp was ~150*F and ESC ~115*F. And whats the deal with fan burning out?
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Old 02-23-2011, 12:16 PM   #2279
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This is what Im starting to think and my foams in my stock tires are basically non existent which probably means more tire spin and maxed out RPM. The battery is def still good, I just dont think its enough juice with the ESC being a 120Amp and the battery being rated at 20C-30C. Do both these factors make sense, since last week I ran the same set up but my motor temp was ~150*F and ESC ~115*F. And whats the deal with fan burning out?
like heavyjeff said, we can really only speculate. as far as the fan, i'm not very familiar with speed passion esc's. you could probably send it back, or just replace the fan yourself. as for the battery, the next time you're at the track, ask somebody if you can borrow a battery, run it and check temps.
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Old 02-23-2011, 12:18 PM   #2280
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like heavyjeff said, we can really only speculate. as far as the fan, i'm not very familiar with speed passion esc's. you could probably send it back, or just replace the fan yourself. as for the battery, the next time you're at the track, ask somebody if you can borrow a battery, run it and check temps.

You may need a higher C rating for that SC setup.

I'm running 25c on a 1/10th scale setup (RSPro/6.5) and it's perfect.

I know my buddies that race SCT's are running the 4.5's, RX8's and 40-50c batteries.
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