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Discussion Starter #1 (Edited)
One of the ideas in testing the Brushless Lipo combinations are for the ease of maintenance for the racers and the long term cost benefits.

However, one of the fears is that returning to 7+ volts is going to put the cars into a supersonic speed range, which was evident by Scot Petitclerc's Lipo/4300 run Saturday at the Velodrome (33 laps in 5 minutes running times from 9.1 - 9.3 for the entire run)THIS IS A 860 ft. track and speeds were close to 65 MPH.

I know there are serveral drivers (Mostly guys who run the Sportsman Mod class) who don't feel comfortable with the idea of these supersonic speeds...

Ideas that are being tested and tossed around are

A) a Slower Motor
B) a FIXED GEAR RATIO (set up for each track)
C) some type of VOLTAGE LIMITING Device, to be handed out like a NASCAR Restrictor Plate.

So far the one that makes the most sense to me is the idea of a fixed ratio class.

For example, at the Velodrome a ratio of we'll say 2.50 turns laps of 11.9 - 12.2, that could be used as the "STOCK" Class ratio

Where a ratio of a 2.10 might yield a 10.4 - 10.7, and could be used as the Sportsman Mod.

Then an OPEN ratio for those REALLY Fast guys...

THREE CLASSES using ONE motor, and if and/or when you wanted to go FASTER...change the PINION~

Joe Myers
South-West Tour "R/C Oval Series"
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Discussion Starter #3 (Edited)
Jimmy,

What about it?

We are in the process of some stuff w/ different motors, but the point was brought up this past weekend at our Velodrome race about using just a single motor w/ a fixed gear combo...which was something I really never thought of...but could work.

The 13.5 on LiPo is FAST~

The 10.5 on LiPo ran nearly 66 MPH average on the VELO

If B/L - LiPo is our future, so be it...let's keep it FUN FOR ALL and LET'S GO RACING~
Joe Myers
South-West Tour "R/C Oval Series"
Official 'TOUR' Sponsors
Jake's Performance Hobbies
Maverick Oval Chassis
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STICK E.T. Tire Sauces
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Fixed gear ratio?

Gear ratio limits bring me back to the day's of running "sportsman stock" here in Flagstaff.The ratio was set to a 15/108 combination.Tire size limited to 2.6".Of course the fast guy's started mounting their own foams cut to 2.599" just enough to pass thru the tech jig we had! Finding wheels that would yield a larger diameter prior to truing became the major challenge! The costs of tires became a crutch for those racers not willing to constantly buy fresh tires.Just something to consider Joe.
p.s. look forward to seeing you @ Mania in april.
Dan
 

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A gear ratio class might work. However, it would seem like it would be a max tire diameter war, or finding motors with the most RPM's.

According to the laws of physics, there is only 1 true way of classifying these motors: The amount of power (Watts) produced at 7.2V.

(Kv rating is no good because it takes torque completely out of the equation. It's a rating with no load. It gives you an idea, but it's not an accurate way to measure power of a motor. You need to look at both RPM and Torque to determine the power of a motor.)

HP (Watts) = RPM x Torque
746 Watts = 1 electric horsepower
I love to quote Big Jim who used to say:
"Horsepower is horsepower! Speed then, is just a matter of gearing."

It's been my opinion for some time, that ROAR should determine our classes by power. Examples:
Stock class: 100 Watts of power maximum
Super Stock class: 200 Watts of power maximum
Modified class: Unlimited power

This way, it does not matter who makes the motor, or how many windings it has, or the types of windings, or the magnets, bearings, or any technology etc.. This solution allows you to even mix and match brushed and brushless, and even different manufacturers. I think the only thing needed for this to happen is an increased availability of dynos.
 

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On the surface a fixed gear ratio sounds like a good idea but in practice it puts a premium on tires. Even Caps will fall into the trap. A few thousands of wear and they will have to be replaced.

A limiting device would work IF it were (as Joe said) handed out like a transponder by the track but it also may open the door to a lot of that “perception” thing that we talk so much about. “His is better then mine” type of thing.

The only way I see that it can be done is through motors. What we need is a brushless with tons of winds to compensate for the higher voltage.
 

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We had a guy running a 7.4 lipo/ 18.5 motor @ RCSM in Phx this weekend. 4-cell 4300 fast lap was 4.1 and lipo/18.5 fast lap 4.6-7 so just a bit slower than 4-cell 4300 but would be a good speed I think. JMO
 

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I have been told by someone who has more knowledge about these brushless motors than "anyone", that in the overall, the Crawler motor would not be suitable for Oval Racing.

In regard to the motor..I would not suggest that anyone run out and buy a 4300 or a 13.5 or a 18.5..for the COF class. All I can say is HAVE PATICENCE. This is just one of those things that we can't have "yesterday". I know we are a want it and want it now society, but as the old saying goes.."EVERYTHING WORTH HAVING IS WORTH WAITING FOR.."

MOTORS: As I have stated on another thread, I would not rush out and buy a motor just yet for the COF class. There are things in the process, while it may not be today for "instant" gratification racers, coming along. If you want to buy the batteries fine, these are the batteries we will use. If you want to buy a 18.5 13.5 or 4300 and play around, fine, just don't expect for certain that these motors will be approved for the COF class. There just may be something better in the works!!! (HINT HINT HINT) No, I won't go any further on this.

Also, we DO NOT WANT to make this a geared class. Who has the largest tires will be in the advantage, been there done that and our Grand Daughter has the 4' trophy to prove it. She never started a race with a tire smaller than 2.6, kept her Grandpa busy "capping foams" every week. :lol:
 

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I agree, a geared class just wouldn't work. You would run tires one time on carpet and be done with them. Well if you want to be fast anyway.
 

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JB said:
I have been told by someone who has more knowledge about these brushless motors than "anyone", that in the overall, the Crawler motor would not be suitable for Oval Racing.
Charlie at Novak says the 18.5 will work just fine for oval racing and that it is made the same as all there brushless motors except the thermal protection for the motor isn't there that is all. So who is the source and why won't it work?
 

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I am more interested in seeing what is being designed now especially for what we need. My thinking is it may be cheaper for one thing but the biggest reason is; if Novak will get behind what we are doing strong enough to design a new motor for us, that could be a very good thing in regards to its future growth.
 

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Discussion Starter #15
Charlie at Novak says the 18.5 will work just fine for oval racing and that it is made the same as all there brushless motors except the thermal protection for the motor isn't there that is all. So who is the source and why won't it work?
Actually Charlie @ NOVAK says OVAL RACERS will KILL the 18.5 motor because of the temp sensor issue. What J.B. says is TRUE and is currently being worked on and tested.

I appologize for this thread to the point I too remember the reason we QUIT the fixed gear class w/ tire size issues, etc. I forget sometimes just how bad RACERS ruin the best things they have. Our FIXED Gear class worked out Great...WAY BACK WHEN - Until the tires started being manipulated. Just as our BREAKOUT class was manipulated, our FIXED Battery Class was Manipulated...and virtually EVERYTHING we've ever done to try to equalize the equipment the racers use and actually make racers BEAT each other on the STAND not in the equipment.

When I posted this I was mainly thinking about "our" situation on our VELODROMES and totally missed my memories of tire size shaving, etc.


Joe Myers
South-West Tour "R/C Oval Series"

Official 'TOUR' Sponsors

Jake's Performance Hobbies
Maverick Oval Chassis
McAllister Racing Bodies
STICK E.T. Tire Sauces

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swtour said:
Actually Charlie @ NOVAK says OVAL RACERS will KILL the 18.5 motor because of the temp sensor issue.
That seems unlikely since races are only 4 minutes. Even the 13.5 comes no where near overheating in 4 minutes.
 

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Most brushless races around here have gone to 5 mins. If you gear them right they don't get that hot.
 

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Discussion Starter #19 (Edited)
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