trailranger

Well hobby shops just walk a fine line on what to stock and in most cases Horizon sends new items sell and push and does a call back if not sold in a few weeks. The remainder of the bread&butter goods are the replacement parts and hardware. For a hobby shop to add one more item into inventory, the hobby shop will have to stop carrying another item. In many cases something old could be clearanced to make room. But the hobby shop just lost a few bucks on that clearance sale giving the hobby shop less incentive to consider taking on risky unproven products.

There used to be a time when hobby shops could stock just one or two brands of sedan parts. Some shops tried adding other brands and they could not stock all the options or replacements needed so racers used internet stores for thier needs, and eventually most hobby shops just reverted back to one or two brands or just stopped stocking slow or hard to move sedan parts entirely because racers are stocking up and not even trying the hobby shop first.

Now the tire market,batteries, off-road, 1/8th, micro, radios and servos are getting flooded with so many brands that it would take over a million dollars in inventory to kept 99% of the possible future weekly sales stocked. Most hobby shops can not afford to have a million dollars tied into slow moving parts, so they just carry the most common parts replaced limiting the part selection to about 20% of the option/replacement parts for a certian model that will cover about 80% of the future weekly sales. And remember hobby shops are not stocking 20% of every brand and model, they are just stocking about 20% of the one or two brands they want to support.

mauromj

iTrader: (26)

Whatever floats your boat...

Quante

iTrader: (6)

I'm gonna answer a few comments with 1 quote

I didnt know that wiring up a 25 or 27t BL was a problem, so I was mistaken there. I actually have no idea how a 21.5 on 7.4V runs in a 12th scale but I can imagin it being on par with a 13.5 or 10.5 or so...

The 10$ saving??? I pay 5$/cell, seeing that I only use 3 packs I can honestly say that doesnt mean much to me considering the rest of the hobby costs a lot more. I do however know that the lower the voltage the more important good batteries become, so with 3 cells I'd prolly have to buy them more often (thats why I say, go up in voltage and go for slower motors, it wont put much stress on motors or batteries, making them last forever).

On the A123 topic, we are both experienced drivers that are driving somewhat on par (the same lap times). I was surprized that he didnt have a lot mre power than me but I think the same that someone else said.
The A123 cells cannt deliver a lot of power, which make them useless for mod, but on 19T they really made the car perform the sae as my car using 4cell nimh.

Buggy Brad

What A-123's did you use? 18650's(1100mah) or 26650's(2300mah) I run 18650's in a 2s2p config in my 12L4 with a 27 single and they work well. I also use the 26650's in 1/10th off-road in the same 2s2p setup and there great, 30 minute runtime and 17 minutes charge time.......BB

Buggy Brad

A few specs on the A-123's.......BB

18650(1100mah)
http://www.a123systems.com/#/products/p4

26650(2300mah) See attached datasheet for more info..
http://www.a123systems.com/#/products/p1

Quante

iTrader: (6)

I remember him saying 2300mAh because his biggest concern was driving hard for 8 minutes without dumping.As far as I know he was running a 2s config.

RTolle

I've got a few comments to throw in here. I've been out of racing for several years now and getting back into it just for fun. I used to be highly competitive in my area and plan to run mod/19t and no stock. I want to go Lipo b/c it is less hassle. Yeah you still need to balance them and what not. But, you don't need a seperate discharger and extra time to do it. You also don't need to worry as much about whether the cells will still be good after sitting for a couple months.

At first I really liked the single cell idea. As the goal is to slow the cars down across the board. At least that's my understanding. I'm all for giving the up and commers their class back (i.e. stock). If that's the case then why change the motor specs for the classes so that they remain even? Shouldn't the rules just switch on some predetermined date? Say, sometime in July when racing is generally slow. All the rules and classes stay the same except for the battery requirement.

The single cell car has another issue that I see. Gearing! From what I've seen it's pretty tough to find proper gearing as is. Decreasing voltage is going to make it even harder b/c you will have to gear up. That may lead to new rear pod designs to allow for more motor movement. Of course the pod designs are already changing to adapt to brushless motors.

The biggest issue I see with the 2-cell setup is speed. Mainly, how do you slow the cars back down with the voltage increase? I don't really have an answer to that. I'm sure someone makes a motor that would be slow enough though.

The main advantage to the 2 cell setup is overall weight and cost. The smaller motors and speedos don't cost near as much as their big brothers. Smaller motors require smaller batteries which further reduce cost and weight. Less weight means that everything is more durable. This option also greatly increases the motor rpm meaning that these ridiculously high gear ratios can be brought back in check. The smaller motors may need different pods. But, it's something that is already changing so what's it mater if it changes a little or a lot? It's still different and non interchangeable with current/previous designs. And, less weight means less tire wear and lower cost.

I've got the equipment to build my car either way. I'm choosing the 2-cell path. At least for now.

Fred_B

iTrader: (1)

Gearing isn't really an issue. They make super small spurs now and pinions way bigger than what we need for 12th onroad.

I can gear up about 10 teeth from what I run now in 17.5 without running into any problems.

The only problem that we have at the moment is the fact that so many people are switching to brushless and buying out all of the gears. Big gears are in short supply so it's a little hard to find them.

Any change isn't going to happen right away. Whatever we come up with it needs to allow us to run NiMh at the big races without completely tearing our cars apart. That's pretty much single cell because all you need to do to switch back is change the battery, receiver pack, and gear. 2 cell would require us to change out a lot more to go to a big race that runs ROAR rules.

RC8

iTrader: (3)

Here are a few of my attempts from years back (about 3 years ago).

1. Straight up Mamba25 on 830mah 2S I think, can't remember for sure. Came in around 500 grams.

2. Mamba25 with a short 380 motor, twin 600 mah 3S LiPo. balanced very nice.

3. No Pic, can't find it. Mamba25 with a normal length 380 (2825?). With twin 1800 mah 3S LiPo.

Glad to see you guys thinking outside the box. I was way WAY to early to get any acceptance from the old crowd, but the times they are a changin'

By the way I think the 1S idea is retarded (literally!) I think Danny is trying to find a solution (ie market) to a problem that does not exist.

John St.Amant

iTrader: (1)

Less is more .. and it doesnt get any simpler than one cell..
That and a 13.5 or even a 10.5 ... perfect . If you think its retarted, concider the ease of it .. the pure and simple clean look. you would NEVER even have to to balance charge it. I'd think twice before you speak so freely about something that you so seemingly have no clue about. If my car ever looked that sloppy I would be ashamed to take the body off of it. Nor does it look balanced in any way shape or form.

RC8

iTrader: (3)

Phhhhtt, one cell? You mean 6 don't you or did you forget about that pesky little Rx pack you have to keep recharging? One more thing to fail. Simple? My ass.

How do figure it's not balanced? Do you know the exact mass of each component? I'd think twice before you speak so freely about something that you so seemingly have no clue about.

And as far as it looks, don't be hatin'!

Roland S

iTrader: (11)

Hi, Steve:

Let me begin by answering your last question. I’ve tested with the very first edition of Diggity, which I shelf now because a special nut that hold the rear pod to the chassis keep coming out. For now, I have CRC’s Blood Knief, T-Force, a two years Diggity and in the middle of putting electronics on a Speed Merchant’s Rev 4. All of these cars are more than two years old. The reason I’m telling these cars are that old is to rebut those who assume you need to buy the newest car or some kind of conversion kit.

Besides being $200 cheaper than a conventional set up and a lot less tire wear, what people would care is how the car performs on a track compare to a car with a conventional set up. Let me introduce you Donny Lia, the current IIC 1/12 Stock A-Main winner, the track/hobby shop owner at http://www.360rcspeedway.com/ I’m going to use his lap time to compare so people can see how the 2-cell set up perform. On the current layout, people would do 10.1, 10 flat, better driver do 9.8, occasionally 9.7 and they would finish with a low 47 laps or high 48 laps. One Friday night, I and Donny did a mid 49 laps. We both were doing more 9.7 and 9.6 and a few 9.5. I’m not trying to compare my driving to Donny’s driving; I’m a decent driver, but certainly my line wasn’t as clean as Donny’s, but the speed of Monba’s 5400kv with 1.7” tire and 88/16 gear ratios definitely help. That was a two year’s old Diggity. My Bloody Knief with this motor: http://www.hobbycity.com/hobbycity/s...ess_Motor_(FIN)
is capable of same performance.
These speeds of these two motors are right in between 27T and 19T brushed motor.
I’ve also try this:
http://www.hobbycity.com/hobbycity/s...ess_Motor_(FIN)
It’s slow. The best I could do was a 10.9, more than a second slower.
May I suggest you try this:
http://www.hobbycity.com/hobbycity/s...ess_Motor_(FIN)
Based on the max. amp load on this motor, 9 amp., compare with the 42ooKv.,max amp load of 10amp., this should have a speed very close to the current stock speed.
It’s only my estimation, the following motor may give you similar speed as 5.5T as you mention in your post:
http://www.hobbycity.com/hobbycity/s...ess_Motor_(FIN)



Use this battery:
http://www.rk2trade.com/rk2trade/pro...roducts_id=161
I recommend this battery now instead of the 1800mah battery, I will explain in the future post.

For ESC:
For those who don’t have an esc yet, you can save yourself $100.00 and get this:
http://www.rk2trade.com/rk2trade/pro...roducts_id=190
You can also use this esc for 1/10 scale, if you only race 17.5 or 13.5 class. Or order this:
http://www.rk2trade.com/rk2trade/pro...roducts_id=189
With this esc you can use any motor down to 5.5 T. I’ve tried this esc myself on an X-ray with 17.5T, it actually gave me more punch than my Speed Passion on a JRX-S type R. Maybe it’s the sensor-less design, but it need to be confirmed by expert whether my thinking is right or not. I think this esc and Speed Passion are made by the same manufacture, based on the program cards available to them. Both program cards have 95% resemblances to each other. I also cross-tested both esc and program card, and they worked. You may want to get it as well; it makes parameter change a breeze, and here it’s the link:
http://www.hobbycity.com/hobbycity/s...ogramming_Card

As I test more and more, here are more reasons to try my set up, specially for those who blah blah why they’re dead against my idea, why they don’t want to buy new item that they have no use for other class. For those who already have a brush-less esc, then all you need is a $20.00 motor and a $20.00 battery. If yours is a sensor type, you simply remove the sensor cable and run the esc as a sensor-less type.

Cogging issue? Well here are my findings:
With both sensor and sensor-less type, I intentionally push the car backward; give a throttle, the car would go forward right away. No cogging here at all.

Under normal running,
With the EZ Run esc, if you gear it right, there will be no cogging issue. With 3100kv motor mentioned above, its speed is slower then a brushed 27T, with a max amp load of mere 7A. I could gear to a point, and it would perform flawlessly. But one more tooth on the pinion, it will show some cogging specially if you try to get it going from dead stop. Is it a good thing? I think so. It make so easy, even a beginner can tell right away if any motor he choose to run is over gear or not. That’s means your gear selection is beyond the capacity of the motor if it cogs. The same cogging happen when I first tried my 6800kv Momba motor. With a 17 teeth pinion, it would cog right away. With a 16 teeth pinion, it would cog 4 minutes into running, when the voltage of the battery drop to a certain point, the cogging happened. Once I change to a 15 teeth pinion, I could go very fast through the whole battery. No cogging at all and the motor was only 150 degree after 11 minutes of running. When geared right, the following motor also has no cogging issue; running at a speed like 8T brushed motor for about 10 minute and came back with 160 degree.
http://www.hobbycity.com/hobbycity/s...ess_Motor_(FIN)


With my Speed Passion run as sensor-less, it can run all the motors, like the EZ Run does, with the same gear ratio. Then I tried to push it and see if it would cog if over geared. It did not cog at all with my Momba 5400 kv geared at 21 teeth instead 17 teeth pinion, supposedly the right gear with the EZ Run esc. It went faster than a 7T brushed motor, can you imagine this; but it was fast only for the first three minute, then it slowed down a lot. The temperature was 240 degrees. With this supposed “better” esc, you can unknowingly over gear, resulting in a less quality run, too fast in the beginning and too slow half way through. So in a way the $50.00 esc is actually a better esc in this case, IMO.


As for as the set up for chassis, toe-in or toe-out, camber and caster are all varied with different cars of mine. But lighter side spring and harder front spring seems work well on all cars of mine.

In the attached pictures, I want you to pay attention to the tires. I purposely use those beat-up tires to see if they would hold up. They do. Since the car is so much lighter, it became less critical as far as traction from softer tires is concern. If the edge of tires broke off and become sharp, just trim it with scissors like the picture illustrated. So far I’ve been running BLACK all around, and it lasts twice as long. Next week, I want to try a harder compound and see if it will work. I think it will, and if it does, the cost to run 1/12 on tire will further reduce. That will be a really good thing.








Quote:
“When i first read our thread i strongly disagreed with your vision of the future of 12th, partly because i felt that you where trying to mess with my class of racing and partly because i have seen and raced against a converted car before in the past, and to be honest it just didn't work”

I only wish the best can happen to 1/12 scale, and I’m working on it even though I’m facing so many objection voices.


Just a Reminder: See pictures I posted on post#78 for detail how to mount the motor.

Wish this will help.

Der Dicke

What do you think about longer runtimes? I think this would be the best way to keep the speed of the cars (specially with Lipos) down. Most speed controllers will handel this good, cause they were also designed for Touring Cars and Offroaders.

trailranger

Not to call you out, but being a smart@ss when your wrong doesn't make it right. John St.Amant was refering to the fact that with Single Cell LiPO you do not need to balance your cells with a LiPO balancer. This would imply that all the ICE, TeamCheckPoint and Super Brains still in use can charge 3.&V LiPO's without the worry of the pack getting out of wack. For chargers without on-board balancers, it can be somewhat of a hassle and possible create user-error when using the external balancer.

As for the RX Pack issues there are voltage boosters that will work just as flawlessly as the Built-In ESC Voltage regulator. In the future, Built in Any-Volt Convertors will most likely used for ESC BEC.

This modual is rated 1A constant and 1.5A max. Not many 1:12 scales push the 1.5A for servo amp draw unless the sevro is oversized. Since most racers already have a 6.3V 3300uf glitch suppression capacitor plug into the RX the 1A 3.7V to 5V boosters should work fine.
http://www.hobbycity.com/hobbycity/s...ooster_for_BEC

Roland, Why didn't you try a smaller motor and has a 1/8" shaft.
http://www.hobbycity.com/hobbycity/s...nner_(Eq:_2204)

Several of the 22 and 28 series outrunners have 1/8 Shafts (AXi, Orion, Turnigy) Plus the the chance of cogging will be less and the rollout will be easier to find since the pinions selection will be wider and rollout change will be less per each 1T change.

I have a 1100KV 50W version of this motor, but recently just bought a smaller 22 series motor for my Solar Car since my Solar Panel is 30W in Full Summer Sun. Even at 20W my solar car is capible of 22mph with a 1000g car.

http://www.hobbycity.com/hobbycity/s...nner_(Eq:_2204)

trailranger

I'm still voting for 3.7V LiPO.

Nothing needs to be invented or experimented with to find a "Stock, Super Stock, Ligh Mod and Modified" Class structure. Just use the current 17.5, 13.5 and Mod motor classes.

Other than buying a battery most racers will have everything already in thier pit box to race 3.7V LiPO. This mean little no additional cost will incur to most racers becuase they DO NOT NEED TO: modify the motor pod, replace chassis for new cell size format, upgrade charger, buy a new motor, buy a sensorless controller because their LRP or NOVAK esc will not work, buy 2.3 or 2.0mm pinions because 1/8" pinions don't fit, worry about having local 1:12 racers in thier new Frankenstine 1:12 class.