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Old 05-11-2005, 09:30 AM
  #61  
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Default Re: Brushless rule changes?

Originally posted by hobbipro
Can anyone else confirm that ROAR has eliminated the 10 turn motor rule, and now both sensor and non-sensor brushless are allowed. I just received my monthly rev-up edition with what looks like non-sensor motors are allowed.
Sensorless motors are allowed, but just about every sensorless motor currently available is illegal for some other reason per the rules. So your only choices in motors are LRP/Reedy and Novak, neither of which has even released the products that they used at the ROAR Carpet Nationals 2 months ago.

I'd also like to point out that ROAR didn't come up with any brushless rules. I'd be surprised if they even thought about them as they're a near exact copy of the IFMAR rules. So if you're unhappy with the rules then blame IFMAR. ROAR could have put some more thought into this though since they know their rules trickle down to the club level where making just about every brushless motor available be illegal is just plain stupid. They made the same mistake with 19T motors and you see where that got them...
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Old 05-11-2005, 12:05 PM
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Unhappy

Can anyone tell me what the height of the Sphere is? I'm able to find the length and width of the Sphere, but no height... I quote the LRP site:

"With its Quantum style design and a footprint of only 33.3 x 37.7 mm (in between the size of a QC-2 and a IPC V7.1), the LRP SPHERE Brushless+Brushed digital speed control is incredibly small for a brushless speed control."

Sounds great, but no height is given.

I now use the Novak SS5800 system in my B4, but it doesn't fit in there properly. The B4 body is simply too low to make the speedo fit the space next to the battery so I placed it on top of the battery bar. Not a very practical situation since you can never remove the battery bar from the car which makes removing the battery a struggle.

Hoping someone can tell me, I'm really looking forward to buying my second brushless system in the very near future!

Greetz,
Michael (Holland)
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Old 05-11-2005, 12:07 PM
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ROAR does have some stupid rules... but I can't see anything all that bad with the rules they currently have documented for brushless motors....

As far as legal controlers go... There are no rules really. Well there are rules for the sensor connector used for controlers that are designed to use sensored motors, but outside of that, there are virtualy no rules for brushless controlers.

The rules for the brushless motors are pertty straight forward as well. Mostly having to do with the physical sizes of things, and some descriptions of the type of wind and type of wire that is allowed... not all that much differnt from what they do with brushed motors...

If there's anything 'stupid' about the brushless rules it's that they allowed the brushless motors to compete directly with brushed motors, yet the brushless motors get to use better magnets and have a higher price limit... Doesn't really seem like a even playing feild to many folks.

Either way, you have to start somewhere.
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Old 05-11-2005, 12:22 PM
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Is there any way we could keep on-topic? There are plenty of other threads for you guys to go and complain about ROAR/brushless stuff.

Somerwil: Here's a little picture of the Sphere installed... maybe it'll help... a little:




Burito, if you could post a full-size pic of the unit installed, that'd be super-duper
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Old 05-11-2005, 05:58 PM
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Is there any way we could keep on-topic? There are plenty of other threads for you guys to go and complain about ROAR/brushless stuff.

This is a LRP brushless thread.............Asking the ones who know the rules before laying down $250+ for a LRP, Novak, hacker, ect is a wise question.
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Old 05-11-2005, 08:05 PM
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Originally posted by burito
First batch of SPHERE speed-controls has been shipped last week, expect them to be available while I write this. Of course it will take a few weeks to fulfill all backorders but the speed-control is in full production now and shipments leave LRP every week.

This is not another "guess" about the release... Again, sorry for the inconvienence but I can promise it was worth the waiting.
Man I have been looking like crazy for this and can't find them nowhere. Has anyone else found them yet at your local store and anywhere on the web?

I think I might be chasing a ghost or at least it feels like it.
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Old 05-11-2005, 08:35 PM
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Somerwil - I'm confident that the height of the LRP Sphere is lower than that of Novak's SS5800 ESC especially since LRP's ESC does not have the aluminum heatsink fins that Novak's has. That being said... like you I also own a B4 (as well as a BK2). The Novak 5800 ESC does fit (tho a bit tight) into the side of both buggies and there is absolutely no need to place the ESC on the battery bar!?! At the moment the 12-Turn power the SS5800 delivers is enough for my needs in 2WD but for 4WD I think LRP's 9/10-Turn results should be perfect! Two things I would suggest for your Novak ESC on the B4:

First - would be for you to make some strategically placed vents over and around the ESC to allow for more ventilation (especially if you use velcro to hold the body to the chassis). The holes or vents will allow for extra air-flow to help keep the ESC's temp at around 140-180 degrees (Fahrenheit) which is it's normal operating temperature. If you start to go above that (averaging 200 degrees Fahrenheit) the ESC could go into it's protective Thermal Shutdown mode for a few minutes. You can place a fabric mesh on these holes to help keep dirt and pebbles out yet it will still allow for some needed ventilation.

Second - If the extra vents allowing more air-flow aren't enough... using a REEDY replacement motor fan (Part # 448) will definitely do the trick! Cost is about $9.00 for it. Here is a pic:


http://www.rc10.com/enlarge/447.htm


Hopefully LRP's Sphere ESC doesn't have any heating problems which especially plagued the first generation of Novak Brushless Systems!


Hope some of this Info helps!
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Old 05-11-2005, 08:53 PM
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Originally posted by Joe Maxey
Man I have been looking like crazy for this and can't find them nowhere. Has anyone else found them yet at your local store and anywhere on the web?

I think I might be chasing a ghost or at least it feels like it.
Hey joe its lee, ill try and get tim to order a couple. if he hasnt already
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Old 05-11-2005, 09:34 PM
  #69  
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OK, thanks very much burito

so I will waiting for LRP brushless product for my first brushless system.

hope it can release ASAP ^_^
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Old 05-12-2005, 12:54 AM
  #70  
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You guys are killing me...
Good to hear that there's big interest for the new product of course.

Height:
The Sphere itself is 15.0mm high, the heatsink (which is most of the time needed for TC applications and pretty sure for 4wd Off-Road too) adds another 11mm on top. There's unfortunately no way to get away without a heatsink in extreme conditions, brushless stuff is just too hot...
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Old 05-12-2005, 10:52 AM
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Thanks for the very quick reply guys, superb!

@ Bob: thanks for the image, but Burito knows it all.

@ Stealth: My Novak heatsink touches the body lightly, so I decided to put it on top of the battery bar. I did not have the heat problem yet, but one of my mates dis have the problem. He also made some ventilation holes to avoid this as you said. Probably the Reedy option you recommended is a better solutution anyway because here in Holland we only have very dirty, sandy tracks with loads of dust. Thanks for the tips!

@Burito: Thanks for giving me the exact dimensions, although I feel a little disappointed about the heatsink issue. I was really enthausiastic when I didn't see a heatsink on the pictures of the Sphere, but now unfortunately there is need for one. With the heatsink, the Sphere is not specifically smaller than the Novak any more, just 7 mm in width. For me (as an off-roader) these 7 mm are not an issue, while in TC application I can imagine it does.

I still feel enthausiastic about the Sphere, so I'm really looking forward to their first appearances in Holland!

BTW Burito: What makes brushless technique more difficult towards heating in comparison to a brushed type speedo?

Thanks in advance,
Michael
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Old 05-12-2005, 11:29 AM
  #72  
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Here's a photo of a clean installation in a touring car:

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Old 05-12-2005, 01:27 PM
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The internal resistance is higher in the brushless mode. Higher resistance means more heat generated at the controler.
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Old 05-12-2005, 10:47 PM
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DynoMoHum,

What makes the internal resistance in brushless mode higher?

Gr,
Mike
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Old 05-13-2005, 12:34 AM
  #75  
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It's not a case of internal resistance actually which makes a brushless speed-control become hotter then a brushed.

I try to explain:
-> more power = more ampdraw = more generated heat.
-> the brushless speed-control generates the field for the 3 coils inside the speedo (what is done by the commutator in the brushed motor). This means the brushless speedo switches the fets all the time during operation (from 1% to 100% throttle position), a brushed speedo doesn't need to switch the fets at full throttle position. This means that the switching losses of the fet's are there all the time in the brushless speedo, while they're not with a brushed speedo when run at full throttle. This does make a difference, since you're on 100% throttle quite often!

Is that understandable?
Hard to explain, but this is just physics of brushless technology and not even we found a way to get around this...
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