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Old 03-15-2006, 07:51 PM   #736
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Quote:
Originally Posted by James
that simple huh? I'll check it out!
yes that simple
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Old 03-15-2006, 10:21 PM   #737
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Quote:
Originally Posted by James
that simple huh? I'll check it out!
I ran about 20% to 10% brake with the 5.5.
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Old 03-15-2006, 10:41 PM   #738
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Hey Fellas
We tried the 6.5 unit with the lrp esc at the state titles late last yr, I sort of disagree with the comment about they arent quiet as quick as the 9 turn. We pulled of second place and the bl was noticeably quicker than all but one Br motor(obviously the guy that won) who was running a lightened 7. The sheer speed on the back straight was awesome ..( note the 6.5 also had the fast lap time of the race)
Even though gearing has to come into consideration with the other drivers .
Run time was awesome for Bl motor Showed no sign of voltage drop off as against the other low turn Br motors..
I just received the 4.5 today so i am interested how that now will compare with the low wind BR motors
Quote:
Originally Posted by TraceRacing
having recently made the very change you are thinking of, here's my take on it.

GTB with 5.5r is a tad quicker than a 10 turn, not as quick in a straight line as a 9, but with greater efficiency found i was reeling in 9t in the final 40-50 seconds as there was no noticable drop off in peformance at the end of the race.

My only gripe with the Noval is the sensor harness wire - if the made an external to motor connection similar to the one on the GTB they could sell loads of different lengths for us to select which best suits our layout. In my Xray the gtb is maybe 10mm away from the motor - but I have about 15 yards of harness to "loop" which looks really messy.
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Old 03-16-2006, 04:04 AM   #739
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Quote:
Originally Posted by TraceRacing
nnick,

at the 1/12th euros some team drivers had a 4 star and a 5 star and were testing them against the 5.5r and 4.5r

according to a driver who was there that I race with, he said on sunday that the LRP lacks punch out ogf the corners. i suspect this is a software problem rather than the motor / esc itself
I know this is not the LRP thread, nevertheless I wanted to comment that...
The information you give is not correct. We had 3- and 4-Star motors available at the race and pretty much all drivers did choose the 4-Star.
Btw, all the drivers that ran our system reported about more torque then when they ran brushed. It's just a more linear acceleration curve with a wider powerband. Not sure which drivers reported to you about lack of punch...
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Old 03-16-2006, 09:59 AM   #740
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I have both the LRP and Novak 6.5T systems and although I prefer the novak system I have to say that the LRP motor has better low end torq.

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Old 03-16-2006, 10:12 AM   #741
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Quote:
Originally Posted by addicted
Hey Fellas
We tried the 6.5 unit with the lrp esc at the state titles late last yr, I sort of disagree with the comment about they arent quiet as quick as the 9 turn. We pulled of second place and the bl was noticeably quicker than all but one Br motor(obviously the guy that won) who was running a lightened 7. The sheer speed on the back straight was awesome ..( note the 6.5 also had the fast lap time of the race)
Even though gearing has to come into consideration with the other drivers .
Run time was awesome for Bl motor Showed no sign of voltage drop off as against the other low turn Br motors..
I just received the 4.5 today so i am interested how that now will compare with the low wind BR motors
i hope that you got the gtb speed control ,the LRP can only handle down to a 5.5 turn motor
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Old 03-16-2006, 03:03 PM   #742
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I'm looking forward to buying a GTB set for my cars

but haven't figured out yet which motor to use, i am planning to use it in the Xray T2 and associated B4 buggy (and sometimes in the sp12 for speedrun)

I drive at varous tracks with modified motors, some are small and technical and some larger and more flowing,
I like fast motors, but disadvantage of brushed ones is the excessive wear which costs me alot for just some practice driving, when racing, i can always put some brushed motor in.
Am thinking about the 4,5 it has to be fast but i am not looking forward to drive half throttle on small tracks (small one is on a basketball field size circuit, geared a 1:7,9 ratio on rubbers with 12t)

Maybe the 5,5 would be a good allrounder, but i want massive speed at higher speed tracks!

In offroad, maybe the 5,5 would be better, was thinking about an overpowered car with 4,5....

or, could you maybe gear out your car so that speeds do not differ that much between motors?

thanks
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Old 03-17-2006, 01:21 AM   #743
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You could but gearing down that much would over heat the speedy. A 4.5 would be the best for on road.
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Old 03-17-2006, 08:50 AM   #744
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With the 4.5 for smaller tracks, you can use a higher ratio and at the same time trim down the End-Point-Adjustment (EPA) on the throttle so that it will not reach the 100% of power as programmed even if you throttle full on the trigger
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Old 03-17-2006, 03:21 PM   #745
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Would'nt there be problems with overheating GTB speedo when you limit the EPA on your transmitter?
My brushed speedo gets very hot when doing that...
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Old 03-17-2006, 03:27 PM   #746
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Quote:
Originally Posted by Erikderaaf
Would'nt there be problems with overheating GTB speedo when you limit the EPA on your transmitter?
My brushed speedo gets very hot when doing that...
Yeah, thats a REALLY BAD idea. Part throttle is where you speedo is working the hardest. Neutral and Full Throttle are the easiest times in the life of a speedo (Actually BL speedos are still working hard at full throttle). Limiting the thottle end point will make the speedo run hot and possibly thermal shut down.

If you want to go slow get a milder motor... a 4800 (10.5) or a 5800 (7.5)

All of this applies to brushed and brushless motors but is even more critical for brushless.

This is not an issue with brakes as they are not on constantly like drive current. You CAN limit breaks with EPS to reduce thier power with no problems.
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Old 03-17-2006, 08:55 PM   #747
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Yea, changing motors is way better than using EPA. Here's a breakdown of brushless motors between Reedy and Novak for your perusal.

Novak Brushless:
4.5R (4.5 turns)
5.5R (5.5 turns)
6.5R (6.5 turns)
7.5R (7.5 turns)
5800 (8.5 turns)
4300 (10.5 turns)

Reedy Brushless:
1-Star (8.5 turns)
2-Star (7.5 turns)
3-Star (6.5 turns)
4-Star (5.5 turns)
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Old 03-17-2006, 11:00 PM   #748
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Where I am from, the ground temperature can get to as high as 60deg Celsius (about 140F) and we have 7mins races. The GTB doesn't thermal, in fact it runs very well with the fan and the hottest measured was up to 70deg Celsius or less. Rather it is the Velociti motor that gets the thermal shutdown, with temperature peaking up to 85deg Celsius or more.

To make 5-7mins very safely on the 5.5R motor with IB3800/4200 under hot weather, I would gear with a ratio of 9.39 and EPA set at 90%. If I were to set the EPA to 100%, the motor will thermal around the 5min mark. At the track I race on, since there is no discernible difference felt to the top speed be it at 90% or 100% EPA, limiting the EPA will be actually better so that the motor don't have to be driven at 100% power, thereby allowing the heat to build up slower.

I am not the only one who does this, in fact a few of us did extensive testing together and eventually came to this. Not the best way to do it probably, but it sure allows me to use what I have now and saves me from buying another motor. But if there is a much better and cost-effective way, I am all for it.
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Old 03-18-2006, 12:00 AM   #749
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I'm not sure using the EPA should result in higher ESC temps for a BL system.
Isn't the BL working just as hard at full throttle, as it is on part throttle anyway?. Even at full throttle, the esc would still be sampling the rotor position and pulsing current to the coils just the same as it would be on part throttle.

If anything, the EPA would limit the amount of coil firing time at top-end and as stated before, reduce motor temps? (I've found this to be the case as well.. the esc rarely overheats, it's the motor that gets hot. My esc only overheated when the fan got jammed with track debris. Then it termalled very quickly indeed.)

Last edited by AngryAsian; 03-18-2006 at 12:34 AM.
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Old 03-19-2006, 05:31 PM   #750
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Well I ran my new GTB+5.5 on the weekend.... It's my first ever race with mod, ever. I've never owned or used a mod setup before.

Car is an XRAY T2.. with a ONE-WAY

Gearing = 84t spur, 15t pinion, 1.7ir. (48pitch) = 9.52 overall ratio

Tyres = Take-Off CS-32 rubber tyres.

Track temp = 50-55C deg. (basically too hot for CS-32's i needed 37's!)
I have three sets of CS-32's left over from the states where I ran stock. They had only 3 runs ea set on them, so figured I'd use these)

Went out for a practice, and instantly discovered I had to severly change my driving style. I quickly learned that the car would spin out pretty badly if I fully backed off the throttle on slight cornering (due to GTB's default drag-brake setup).

I was going to dial-down the drag brake when another T2 driver recommended I fit my spool in the T2 (for a solid axle) as he is running. As soon as I did that, WOW.

This thing is fast. damn fast. scary fast. Our straightway has a curve in it, like a sweeper which is a large 90'deg. I was too scared to hold the throttle for the length! I think I used full throttle in the races only a handful of times. FAST.

after about 10 laps (track average is 17-20 laps).. my tyres were GONE.. they'd gone totally off.

another racer suggested I 'look after my tyres when racing mod'. I think what he means is. dont be so trigger happy all the time. Coz this thing just light's up when you nail it. full on.

In my first race, I started to get what felt like glitching, I'd loose my steering/throttle for a split second. I use spektrum, I'm wondering if my rec isnt getting the voltage it needs and it's resetting on the track. Perhaps I need to install the cap for it now. dunno, never experienced that in stock.

I run brand new IB3800's, matched. After each race, I was coming off the track and discharging straight away. I was getting up to 2300mah out of my cells AFTER the race!!! on the discharger! 2300!!! I couldnt believe it. That means my GTB/5.5 is using around 1900-2000mah on the track. WOW! only half the cell pack's capacity. Seriously this is about what my brushed stock/GTX setup was using... I cant believe it. I'm shocked.

my results, for my first ever mod race, 3rd, 2nd, last (broke a suspension part) 2nd overall for the day. Not bad, for my first outing in mod class.

I'm actually the current 'stock' State Champion...

I feel like a begginer, learning r/c all over again. what a buzz.

My motor (the 5.5) was coming off the track really really hot, almost too hot to touch in some cases. the GTB was fine. track is pretty tight, and technical. Some guys were suggesting I gear it up a little more, but I didnt really even use full throttle, and I was running a couple of pinions down from what some fellow racers were running.. I felt it was ideal

This w'end... foams, a different / massive track, more gearing... cant wait!
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