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Old 03-23-2009, 08:50 AM   #31
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I think the biggest issue is for guys with t-plate cars. Although it would be possible to run 2 cells in parallel for increased capacity, 2p1s ? I raced 12th with a resistor speed control(more like a light switch) and six cells. heavy cars break bad when they hit something at high speed, tire wear is higher with heavy cars, especially on asphalt and concrete I am all for 1 cell, no special lipo charger or matcher is needed. A brushless motor with no maintenance required. No comm lathe. I have wondered about 380 size stuff also for awhile, my 18r was un drivable with a 14 turn mod and 2s lipo. It probably would have been perfect in a 12th.
When the tax man returns my money, its going into a 12r5, tekin or novak speedo, SMC 1 cell packs and what ever motor the let me run at the track.
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Old 03-23-2009, 10:25 AM   #32
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I've heard the reasoning is that the motors between classes are interchangable. NOT. all the fast guys will buy special light weight motors ala Novak Light to work around the real problem of excess weight. And the extra weight of the motor is in a terrible place from a handling standpoint.

Here we go again.....

Exactly, here we go again. You can run the same motors with single cell (stock, superstock, and mod). You can't run some odball 380 stock motor in offroad or sedan during the summer.

Fact is that there are a ton of reasons that 380's won't fly. I won't waste my time listing them out here because single cell is winning the battle already. More cell manufacturers are jumping on the single cell game already. To run a 2 cell set-up you'll have to build your own stuff because it's not made for 12th.
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Old 03-23-2009, 12:10 PM   #33
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Although it would be possible to run 2 cells in parallel for increased capacity, 2p1s ?
I haven't looked inside my SMC 3.7 pack, but I'm fairly sure it already IS made up of two cells in parallel.

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I am all for 1 cell, no special lipo charger or matcher is needed.
Word of caution... if the single cell is a LiPO, you DO need to use a LiPO charger.
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Old 03-23-2009, 12:31 PM   #34
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The real trick here is getting all the 1/12 scale guys to realize that 540 motors were designed for 1/10 cars. strapping a big block chevy into a go-cart is not ideal for handling. Originally, 1/12 DID have smaller motors when they were introduced, and they are waay more powerful now..
That'll be a great trick, since it isn't so. From day one, 1/12 cars had 540 size motors in them. This was before 1/10 cars came along, by the way. It's a pretty safe bet that the 540 motor wasn't designed for a 1/10 car which didn't exist.

1/12 cars NEVER had smaller motors. The motors were a lot weaker back then, but with 1000 mah batteries they could only make so much power and still offer usable run time.
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Old 03-23-2009, 04:23 PM   #35
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my 2 cell lipo car wieghs in at 550 grams. that's better then 800g, right? and runtime is not an issue. 10 min. minimum w/ a cheapo $10 lipo.

once you run at 550 grams, you'll never want to run at 800. A mod 1/12 at 550 grams is like driving a shrunken formula one ferrari. and that's goooood.

The real trick here is getting all the 1/12 scale guys to realize that 540 motors were designed for 1/10 cars. strapping a big block chevy into a go-cart is not ideal for handling. Originally, 1/12 DID have smaller motors when they were introduced, and they are waay more powerful now.

I've heard the reasoning is that the motors between classes are interchangable. NOT. all the fast guys will buy special light weight motors ala Novak Light to work around the real problem of excess weight. And the extra weight of the motor is in a terrible place from a handling standpoint.

Bottom line: the motors need to be down sized to ~380 size. This is the time to set the future of 1/12 as there is massive opportunities for improvement. Single cell? No. 380 two cell (or 3 cell!) lipo? YES YES YES

Here we go again.....
I was with you on the small motors back in November, but I was wrong.
After a few months of actually racing with the SMC single cell lipo, I know it was the right way to go. Both in 1/12 and WGT, it's the right way to go. The ESC voltage thing is not an issue. The trick for running the booster directly from the battery lead works with nearly every ESC I've tried. I even had an old Novak Hammer brushed running with a single cell.
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Old 03-23-2009, 09:20 PM   #36
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I'll agree with Trips about the motors sizes. 1/12th was out years before the 1/10th came out (1985- introduced by Bolink at the Winter Nationals in Orlando, Florida). We only raced either 1/8th gas or 1/12th. Motor size was always 540 and I've got my orginal motor .
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Old 03-25-2009, 07:30 AM   #37
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trips, you are right, the motors were not designed for the cars, the size of the cars was partially determined by the motor size. I was not clear what i meant.

regardless, the battle seems to be won. lets all be lemmings and not advance the sport. it worked for brushed motors and nicads for 15 years.

and as far as using the same motors year round? thats a joke. oh no!, i need to buy an additional $50 motor to run a new class. i'm sure that will send everyone heading for a new hobby. how much money do all you have into the hobby as a whole? and you are going to let one $50 item dictate the future of the class?

btw? how much does an smc single cell lipo cost? how about the lead plate to meet weight and balance the car? remember, a set of tires is ~$40. and a 800 gram car will wear them faster then a 550 g. car. right? what about parts breakage, and body damage? how much does a body cost?

EXACTLY!

i'm done now, you guys win. hope it works out for everyone.
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Old 03-25-2009, 08:14 AM   #38
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btw? how much does an smc single cell lipo cost?
Around $50.

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how about the lead plate to meet weight and balance the car?
I don't know. How much os the lead plate for your 7.4v small motor car?

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remember, a set of tires is ~$40. and a 800 gram car will wear them faster then a 550 g. car. right?
I'm paying around $23 for a set of tires. I'm not at 800 grams, and I've got four race days on my current set. Looks like I can go two more race days before I need a new set.

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what about parts breakage, and body damage?
I haven';t broken a part in a long time, and with the lighter 3.7 car, I don't expect to break anything ever again. I had a bad solder joint in the car that was causint the receiver to shut down at random. HTe car took some fearsome board hits, maybe the loudest "Schmack" sounds I've ever heard, and no breakage of anything. Haven't broken the body.

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how much does a body cost?
14 or 15 bucks here.

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EXACTLY!
Exactly what??

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i'm done now, you guys win. hope it works out for everyone.
You make it sound like a contest... so what do I win??
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Old 03-25-2009, 08:25 AM   #39
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Rev Rev Rev...perspective, man.

I agree with you on SOME counts, but strongly disagree on others. To start...the small motored car you built will NEVER grow the class. YOU could barely control it--it was a missile looking for a target. There are TWO reasons for that. 1) 2s LiPo is WAY too much power for a stock motor (for most drivers not named Baker, Blackstock, Lemieux, etc), much less the motor you installed which was dictated by b) sensorless motors have to be ridiculously low wind in order to work at all in car applications without major issues.

I DO agree that bringing LiPo cars up to weight is an exercise in futility...why give up the advantages of lighter weight when it's not necessary unless someone is trying to run the 1s cars mixed into another class (more on this later). You may have missed it (I doubt that) but the demo race just over a week ago AT YOUR OWN CLUB ran the cars at a 700g minimum--nobody was really having to add any weight. And it was WONDERFUL to drive the lighter cars. Virtually zero tire wear, impacts are less harsh, and it was like stepping back into the 80's as far as car "feel". As Trips mentioned above (and was SPOT on the money) the all-up weights of 1/12 cars crept up with battery capacity...we didn't really notice what had happened. Then BAM, we drop the weight back to where it was and see how ponderous they'd really become. If I ever drive a "round cell" car again it will be too soon (next Sunday, unfortunately). The thicker chassis we run today also contribute to this avoirdupois.

I also agree that holding a gun to 1/12 collective head to run "the motor we've always run because I want to use the same motor in everything" is, on it's face, a ridiculous premise...but watch, it's EXACTLY what we'll be stuck with even though there ARE alternatives (again, more on this later). We're wedded to the 540 via a shotgun marriage that has NO legitimate supporting argument. Our cars are smaller, they'll use different batteries regardless the configuration chosen, servos are smaller, etc. The only damn part that carries over is the stupid motor and MAYBE the esc. Folks who haven't tried it should quit whining and buy another motor. Sheesh...you've probably got extras from your (T)axi (C)ab sitting in your box you bought looking for that one mystical rotor. Where was your whining then?

Now, this past Sunday in our 1/12 Stock class I ran my 1s car EXACTLY as it ran in the Denver Demo other than installing a 13.5 motor. My CRC 3.2R with Novak GTB / 13.5 motor and SMC LiPo weighs 755g all-up with a standard weight body w/three color paintjob that isn't particularly light, so 700g would be a fairly attainable minimum with some attention paid. I ran the exact gearing that I ran at Denver all day. In the main my car had the fourth fastest lap behind two brushless cars and a brushed car. I'd qualified third behind the same two brushless cars. JP's fastest lap was almost .3 faster, John's fastest lap was about a half tenth faster. Top five John was still about a half tenth faster, JP was about 1.5 tenths faster. Top ten and twenty John held his half a tenth advantage while JP's advantage fell to just over a tenth. As it turned out, I ended up winning the race because both the Poulson brothers ran into problems negotiating traffic in the other 32 laps that aren't found in the top 20, but my point is made in those top times. I'm pretty sure I could have gained some speed by playing with the gearing, but that would likely have been countered, in whole or in part, had I run the car at the same weight my round-cell 17.5 bretheren were at. As it was my car was probably 100-150g lighter than they were. I think that there is a real opportunity to phase 1s LiPo into our racing by mandating the same weight and a 13.5 motor in the 1/12 Stock class. Give up about 25% in voltage, gain about 25% in kv.

What I'VE spent a fair bit of money to test, and look forward to putting it on the track at a practice day later in April, is the Novak Mongoose 380 system. I've got the 13.5 and 8.5 motors and will try to get a 10.5 prior to the test. (what you'll find is that the sensorless motors most folks have been trying are FAR lower wind than these). What I know going into this test that creating equivalence with existing spec classes will probably not be possible. The Novak Three-80 motors have FAR more kv than their same wind 540 counterparts, but also have FAR less wattage (torque). We'll see what happens, I'll be interested in trying all three motor combos with and without ballast and see where we're at.

Something JP and I talked about on our way home from Denver was that we really haven't run 1/12 SuperStock at all this year (I think two club races and at our 2-day). Maybe we could create an open mod class that would encourage some experimentation with alternate motors and masses. What we discussed was spec'ing the SMC 1s battery (may as well get used to it...I'm almost certain 1s is what's going to happen in ROAR and elsewhere, and having tried it now I'm in 100% agreement) and spec'ing the oa width, etc but leaving motors, weights, etc wide open. I'm guessing that a 600g car is entirely do-able. The Mongoose system doesn't weight THAT much less than the 540 systems, but I'm thinking that the lighter weight makes the 2.5mm thick chassis we've been running overkill so we could shed some weight by going back to a 2mm or so chassis.

Exciting times we're living in if one keeps an open mind and such.
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Old 03-25-2009, 09:27 AM   #40
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Scott, have you tried a stock motor with a 7.4v lipo? I ran that combo last week and raced it with the 19t/13.5 class. It wasn't not at all balistic.
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Old 03-25-2009, 09:48 AM   #41
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Scott, have you tried a stock motor with a 7.4v lipo? I ran that combo last week and raced it with the 19t/13.5 class. It wasn't not at all balistic.
First question...whose great idea was mixing 19T and 13.5? I'd be back to running brushed Komodos in a New York minute with that field.

Second question...just what do you propose as an "entry level" class for 1/12?

Observation...my argument, shared by many, is that the existing 4-cell Stock class isn't particularly "newbie-friendly". Hell, I've seen experienced racers that would do better with LESS power. If, as you say, 2s and "stock" is at the speed of a 19t (a premise that I don't think I agree with...I'd estimate it to be faster...but not having personally tried it I'll concede the point) that doesn't bode well for entry level. The 1s LiPo makes a 1s/17.5 class a VERY reasonable entry/lower power class, 13.5 a great Stock replacement and from there go nuts.
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Old 03-25-2009, 10:19 AM   #42
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Rev Rev Rev...perspective, man.

I agree with you on SOME counts, but strongly disagree on others. To start...the small motored car you built will NEVER grow the class. YOU could barely control it--it was a missile looking for a target. There are TWO reasons for that. 1) 2s LiPo is WAY too much power for a stock motor (for most drivers not named Baker, Blackstock, Lemieux, etc), much less the motor you installed which was dictated by b) sensorless motors have to be ridiculously low wind in order to work at all in car applications without major issues.
Scottrik,

Steve was running a 3s 11.1 volt 420motor equivalent to prove some new 1/12th scale theories. His ideas are sound, and yes the car is fast, but he was running consistent 10.4's for laptimes, so I not sure about barely controlling it. His point was to prove the theories of improved performance, lower weight, and reduced cost in 1/12th scale. I believe he was successfull on all counts.

Regarding your Novak Mongoose, I currently run in Denver with a Novak Mongoose 10.5 in a CRC 3.2R with a 2000mah 7.4v. The car was identical to Steve's on the straightaway, but had less punch in the infield, so it was easier to drive consistently. I was running on the same layout, and turned High 9's to low 10's consistently. My car weighed in at 550 grams and used around 1100 mah's for an 8 minute race. The speed with the 10.5 Mongoose was equivalent to the old 4-cell mod 9/8 doubles. Overall, excellent car and tons of fun to drive.

BTW - start your gearing pretty low with the 10.5 or lower mongoose systems. With the 7.4v setup, I had a 100/17 64p with 1.72 tires, and it was pretty darn close.

In summary, the Novak Mongoose with a 7.4v 2000mah battery is an excellent performer, very smooth, extremely inexpensive ($140.00 for motor and esc) and is a viable option. I encourage people to try the 13.5 system and have some fun. I haven't grinned this much in 30 years of racing
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Old 03-25-2009, 10:31 AM   #43
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Scottrik,

Steve was running a 3s 11.1 volt 420motor equivalent to prove some new 1/12th scale theories. His ideas are sound, and yes the car is fast, but he was running consistent 10.4's for laptimes, so I not sure about barely controlling it. His point was to prove the theories of improved performance, lower weight, and reduced cost in 1/12th scale. I believe he was successfull on all counts.

Regarding your Novak Mongoose, I currently run in Denver with a Novak Mongoose 10.5 in a CRC 3.2R with a 2000mah 7.4v. The car was identical to Steve's on the straightaway, but had less punch in the infield, so it was easier to drive consistently. I was running on the same layout, and turned High 9's to low 10's consistently. My car weighed in at 550 grams and used around 1100 mah's for an 8 minute race. The speed with the 10.5 Mongoose was equivalent to the old 4-cell mod 9/8 doubles. Overall, excellent car and tons of fun to drive.

BTW - start your gearing pretty low with the 10.5 or lower mongoose systems. With the 7.4v setup, I had a 100/17 64p with 1.72 tires, and it was pretty darn close.

In summary, the Novak Mongoose with a 7.4v 2000mah battery is an excellent performer, very smooth, extremely inexpensive ($140.00 for motor and esc) and is a viable option. I encourage people to try the 13.5 system and have some fun. I haven't grinned this much in 30 years of racing
Great post Rcoldman, My original intention of posting was to see if the 7.4v 2 cell was viable and should be tested in the 1/12 scale. Unfortunantely it turned left instead right. I agree that 1 cell is an option but I also agree that 2 cell should get it's fair share of consideration for a 1/12 scale.

Anyone else have a positive input on running 2 cell 7.4v lipo? Please post your success story here and what combos are you running. I definitley have to try the novak mongoose option. Thanks again RColdman!
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Old 03-25-2009, 10:34 AM   #44
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yes the car is fast, but he was running consistent 10.4's for laptimes, so I not sure about barely controlling it.
I think when I saw it (when I was there at Christmas) he was a bit earlier into the experience. It was fairly ballistic and he had the broken parts to prove it (I gave him a lower arm or two). My point was that Steve is a FAR better than average driver and it was (to my observation) a task that was pretty much at least the equal to his substantial skill. Mere mortals were going to have problems, at least as the test mule was when I observed it.

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Regarding your Novak Mongoose, I currently run in Denver with a Novak Mongoose 10.5 in a CRC 3.2R with a 2000mah 7.4v. The car was identical to Steve's on the straightaway, but had less punch in the infield, so it was easier to drive consistently. I was running on the same layout, and turned High 9's to low 10's consistently. My car weighed in at 550 grams and used around 1100 mah's for an 8 minute race. The speed with the 10.5 Mongoose was equivalent to the old 4-cell mod 9/8 doubles. Overall, excellent car and tons of fun to drive.

BTW - start your gearing pretty low with the 10.5 or lower mongoose systems. With the 7.4v setup, I had a 100/17 64p with 1.72 tires, and it was pretty darn close.

In summary, the Novak Mongoose with a 7.4v 2000mah battery is an excellent performer, very smooth, extremely inexpensive ($140.00 for motor and esc) and is a viable option. I encourage people to try the 13.5 system and have some fun. I haven't grinned this much in 30 years of racing
I'm looking forward to trying the sensored 380's and appreciate the input. I WON'T be testing on our club's carpet with an un-cased LiPo, though, so that's pretty well out.

I, as much as anybody, appreciate what you guys have tried and your results. I'll not be headed down that particular path (2s), though, because I'm pretty sure it's either a) a blind alley when taken as a "big picture" (doesn't have anyplace that I see for folks coming into the class or who don't want ballistic performance) or b) not where the market/class is going to go. Or both (most likely scenario imho). I can't see spending money (or, more importantly, time...we don't have the luxury of test time here) on something that I don't personally envision "happening". Really, I'm pretty sure chasing the 380 setup is pissing into the wind too but THAT is a viable avenue to my mind that has room at the table for everyone, novice and expert alike. Whether it becomes accepted or not is certainly another matter, and I don't realistically see it happening. Too much inertia.
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Old 03-25-2009, 11:03 AM   #45
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That'll be a great trick, since it isn't so. From day one, 1/12 cars had 540 size motors in them. This was before 1/10 cars came along, by the way. It's a pretty safe bet that the 540 motor wasn't designed for a 1/10 car which didn't exist.

1/12 cars NEVER had smaller motors. The motors were a lot weaker back then, but with 1000 mah batteries they could only make so much power and still offer usable run time.
Trips,

Yes, as most of us old people know, most original 1/12th scale cars came with some version of a "300" size. I raced Tamiya Porsche's with 340 motors, but we always wanted more power at the time (remember, this was 34 years ago 1975 or so for those of us that are old enough). All my 1/10 Tamiya's and other brands were similarly equipped. It just depended on the kits at the time (Heathkit, Tamiya, MRP, Bolink) as to whether you received "300" series or "500" series. The Associated RC12 was a nice revelation with the '05' 540 Mabuchi series.

The overall point is, the new brushless motors operate at a more efficient, higher power level than the older brushed versions. So just like airplanes and Helo's, it's a good time to review smaller, lighter motor options that deliver the same power with lower costs and more efficiency than their larger counterparts.

BTW - For the history buffs, a fast/peak charger back then was 2 wires hooked straight from a 12v car batter to your 7.4v nicd. You knew the battery was charged when the wires and cells were hot. (I only blew up 3 or 4 packs). This new Li-po stuff is GREAT!!!!
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