R/C Tech Forums

Go Back   R/C Tech Forums > General Forums > Electric On-Road

    Hide Wikipost
Old 10-28-2016, 12:43 PM   -   Wikipost
R/C Tech Forums Thread Wiki: 1/12 forum
Please read: This is a community-maintained wiki post containing the most important information from this thread. You may edit the Wiki once you have been a member for 90 days and have made 90 posts.
 
Last edit by: fenton06
This is a place to share knowledge related to 1/12th scale racing. It is not to be used for conversations.

KITS:
Click links to go to manufacturer product page. If any are missing please add them!

TIRES:
Pre-mounted tires readily available in the US:
Pre-mounted tires readily available in the Europe:
  • Hot Race ??

Gluing your own donuts:
https://www.youtube.com/watch?v=hm7z1rz-74s - Special thanks to Edward Pickering!
Truing tires:
https://www.youtube.com/watch?v=8wqHOLWq6Uc - Special thanks to Edward Pickering!

The following information came from HERE, with some editing and information added. Thanks Christian!

THIS MAY NEED UPDATING FOR THE NEW BLACK CRC CARPET

Brands:
BSR, CRC, Jaco:
Pro One is no longer selling to the public, but it and the brands above are all mounted by BSR and use the same foam. The nomenclature of the BSR vs Jaco/CRC is a little different in a few instances but is otherwise the same. The BSR foam consists of three families, and can be identifed as synthetics, naturals, and blends.

Synthetics - The old school, light weight, easy to true "dry feeling" tires. These include tires like CRC/Jaco Yellow (BSR White), Black, Gray, etc. These tires offer the highest wear rate and lowest grip. Many racers continue to use these nder high bite conditions.

Naturals - These tires are usually the best alternative for low bite and asphalt. They include Pink, Magenta, Double Pink, Lilac (BSR Team Purple), Purple, and other tires. These tires provide a ton of grip, but tend to get sticky in high bite conditions. This rubber does not wear as easily, and the cars will pick up gunk and fibers from the carpet under most high bite conditions. This is especially bad if the humidity is high.

Blends - These are the tires most people run today. They were initially called "JFT foam" by some, as it was believed that the tires were the same as the JFT tires. We can divide the blends further into two groups: high rubber and low rubber content. The high rubber would be the new rear Orange and Red from the BSR family, and the low rubber would be the Green and Blue varieties. When, asked about the difference, John Foister from BSR Tires said they came from the same "family" of foam, but they offered different grip. According to John, the Green/Blue has more bite than Orange/Red, but from track testing Oranges offer more bite than Green (being equivalent to in hardness) when the grip is high and absolutely no grip when it is lower. The Orange foam has a denser pore structure and the tire is not as prone to chunking. It is also important to note is that BSR Blue rears are not the same as the BSR Blue fronts!

JFT:
JFT stands for Japan Foam Tire. They started the new wave of foam tires we are all using now (Blue/Blu, Green/Greene, Dbl Blue, etc). These tires are a little different than the BSR tire family, but work in very similar conditions. They offers four varieties A (asphalt), C (carpet), S (???), and R (???). This does not mean that those types only work on that surface, but this is what they recommend.

JFT uses the same foam for fronts and rears if the color is the same.

A: Used on asphalt, considered close to the natural rubber variety and are named consistently with other natural tires.
C: Used on carpet, considered a blend.
S: Used on carpet?, tires are ???
R: Used on carpet?, tires are ???

For setup, the JFT foam seem to generate more bite than the BSR, therefore the car tends to be a little more aggressive.

Ulti:
Ulti is another Japanese brand that offers an array of compounds. They have their own way of rating tires, and are difficult to equate to other brands. They have 4 different varieties, each in varying degrees of hardness.

J: High rubber content tire, similar to Pink/ Magenta. Soft would be close to a pink. These offer the most bite and are great for asphalt/carpet front tire. (J hard being very popular)
X: "Balanced" blend, similar to JFT Blue/ Green. Soft is equivalent to Green, medium to Blue in hardness. Great for carpet!
Y: High synthetic blend with lower grip, and is not a very popular variety.
Z: A very expensive "special" foam that is supposed to be magic on asphalt. Only make it in soft shore.
European tires:
There are many great European foam tire brands that use their own types of foam, as well as traditional foams. SOmeone with more knowledge about them will need to fill this in!

Tire Diameter:
If you are racing on carpet, you have to evaluate how much grip your track has. If your track is low to medium grip, you can run bigger tires. If you are on higher bite you have to cut them smaller, there is simply no way around it. Bigger tires are needed for asphalt, especially in the rear. The larger tires provide much needed lateral bite.

Carpet (mm):
Low - Medium Bite
Front: 42.0 - 42.5
Rear: 42.5 - 43.00
Medium - High Bite
Front: 40.5 - 41.0
Rear: 41.5 - 42.0
Big Race
Front: 39.5 - 40.0
Rear: 40.5 - 41.0
Asphalt (mm):
Parking Lot
Front: 43.0 - 44.0
Rear: 44.0 - 45.0
Prepped High Bite
Front: 42.0 - 43.0
Rear: 43.0 - 44.0

Tire Saucing:
Most facilities have moved towards odorless traction additives such as SXT. Some of additives evaporate very quickly and some do not. This seems to be something that is also dependent on tire compound and ambient temperature. For example, saucing a Green compound seems like it never dries, especially when tjhe temperature is lower. We have found that wiping the tires off 15 minutes before we go run allows the sauce to cure, which makes the car come in much quicker with Green rears. Blue compounds on the other hand, do fine when wiped off right before hitting the track.

Saucing half front and full rear is a good initial starting point. If the front of the car is too agressive you can sauce les than half, or for a shorter amount of time.
Tire Fuzzing:
In conditions of increasing grip, foam tires will somewtimes get sticky and pick up fuzz and debris from the track. This is highly dependent on the rubber sedan tire that is being run at your local track and the compound/ type of foam you are running on you car. The softer the sedan tire and the harder/higher rubber content in your foam tire, trouble with fuzzing seems more likely to occur.

There are ways to get around fuzzing under most conditions, and usually involves the selection of the correct foam compound. The more fuzz you get, the softer/lower rubber content you want to run.

Examples:
Problem: Car fuzzes with Lilac/Team Purple fronts and car starts pushing.
Solution: Use a softer front tire and or different family of foam. Replace it with Blue or Double Blue front.

Problem: Car loses rear bite 6 minutes into the run. Blue rear tires look almost clean but have small carpet hairs.
Solution: Use Green rear tires. The softer compound wears instead of getting sticky, minimizing fuzz.

Tire Selection:
Starting out, pick 2 tire compounds for the front and rear. The following should have you covered 99% of the time.

Front - Green and Blue (BSR) or Green and Light Blue (JFT)
Rear - Blue and Double Blue (BSR) or Blue and Dark Blue (JFT)

You may wonder about other compounds out there and if they might be better, trust me, they probably won't be. Even if there are other tires that can be as fast, the synthetic family wears out really fast and the high natural rubber will probably fuzz on you over an 8 minute run. The blends family seems to be the most versatile foam type available today. They last awhile, and sticking to them will make your process of tire selection simpler.
Tire Charts:
BSR/CRC/Jaco



Contact



Corally



JFT (Japan Foam Tire)



Ulti



Enneti (Xceed)



ELECTRONICS:
ESC:
As of now, ROAR is staying 1S (3.7V nominal; 4.2V fully charged) for 1/12. There are many 1S ESC's with a built in BEC so nothing else is required to power the receiver and servo.

If you don't want to lock yourself into a 1S specific ESC, you do have other options! It is possible to use your 2S ESC without a booster or receiver pack, and the ESC simply supplies the lower voltage. If that does not appeal to you, you will need to use an Rx pack or booster. The Rx pack and booster will both supply the receiver with a higher voltage than the 1S pack.

If you decide to use an Rx pack, MAKE SURE TO REMOVE THE RED WIRE FROM THE ESC PLUG THAT GOES INTO THE RECEIVER!!!

If you choose to use a voltage booster, it works exactly how it sounds. Instead of plugging the ESC into the receiver, it plugs into the booster, and the booster plug goes to the ESC, supplying the higher voltage.

1S ESC:
If there are any missing please add them!!

If anyone would like a need for a chart comparing the ESC's specs PM fenton06 and I'll get one made and put in here!
Voltage Boosters:
If there are any missing please add them!
Servos:
BODIES:
Black Art (CRC - US Dist):
  • Audi R8C - BA002 - .020 Thick



  • Black Market (Mohawk 12) - BA005 - .020



  • Lola B10 - BA006 - .020 thick
  • Toyota TS030 - BA008 - .020 thick

    Lola - black/red, TS030 - green/pink


PROTOForm:

Reflex Racing/RSD:

SUSPENSION ADJUSTMENTS:

Print Wikipost

Reply
 
Thread Tools Search this Thread
Old 01-26-2006, 03:03 PM   #17101
Tech Adept
 
Join Date: Jan 2006
Location: Green Bay WI.
Posts: 249
Send a message via AIM to mush104
Default

would anyone have a setup for a ft.L4 on a low to med. traction track
mush104 is offline   Reply With Quote
Old 01-26-2006, 03:22 PM   #17102
Tech Fanatic
 
Join Date: Jun 2005
Posts: 900
Default

One thing that makes our cars what they are is the rule about a solid rear axle. Many years ago, the Japanese sold fully-independent suspension 12th cars, and they would run rings round the current design today.

I'm not sure about the T-bar / pivot debate, but wherever they run together the T-bar car is always faster on carpet. Maybe those who do make the pivot car go well (eg, Cleveland and Snowbirds) have some secret that they don't share with us, but for the average Joe, a T-bar car is easier to set-up, and faster.
SlowerOne is offline   Reply With Quote
Old 01-26-2006, 03:29 PM   #17103
Tech Addict
 
jasons56's Avatar
 
Join Date: Apr 2005
Posts: 685
Default

Its amazing to me how many "full size" automotive engineers are clueless about "full size" PERFORMANCE dynamics. Its no surprise many don't have a clue about RC dynamics.
I had a aged college Mech Eng Professor actually claim that it was impossible for his 4wd Carrera to get beat by my 56' Chevy in a drag race. Because 2 tires carrying 50% of the weight and 100% of the traction could not possibly provide as much acceleration as 4 wheels doing both. Of course, that WAS considered automotive truth when HE was an undergrad. At one point it was even taught that racing speeds would hit a brick wall at 1 G, because no tire could grip more laterally than the weight on it. This was before anyone was using downforce as well.
Took me 3 semesters to actually get a race out of him. He beat that poor Porsche so hard it made me cringe. Bwahhahha. I guess he had never heard of a wheelstand either! Its amazing how open headers put the fear of God into those un-initiated with the racetrack.
jasons56 is offline   Reply With Quote
Old 01-26-2006, 03:37 PM   #17104
Tech Addict
 
jasons56's Avatar
 
Join Date: Apr 2005
Posts: 685
Default

Quote:
Originally Posted by SlowerOne
One thing that makes our cars what they are is the rule about a solid rear axle. Many years ago, the Japanese sold fully-independent suspension 12th cars, and they would run rings round the current design today.

I'm not sure about the T-bar / pivot debate, but wherever they run together the T-bar car is always faster on carpet. Maybe those who do make the pivot car go well (eg, Cleveland and Snowbirds) have some secret that they don't share with us, but for the average Joe, a T-bar car is easier to set-up, and faster.
I'd believe that an independent rear might be a benefit on a rough track, but on a smooth carpet track I've got to wonder if the simplicity/weight benefits of the current design would even out the benefits.

I know of a few "average Joe's" around here that get around pretty damn well with the link cars. If they went any faster with a T-bar car they would be running laps as fast as the the best drivers nationwide. I don't think that would be the case.
jasons56 is offline   Reply With Quote
Old 01-26-2006, 03:42 PM   #17105
Tech Master
 
burgboyz's Avatar
 
Join Date: Jan 2005
Location: Da 'Burg
Posts: 1,247
Trader Rating: 70 (100%+)
Default

Quote:
Originally Posted by SlowerOne
One thing that makes our cars what they are is the rule about a solid rear axle. Many years ago, the Japanese sold fully-independent suspension 12th cars, and they would run rings round the current design today.

I'm not sure about the T-bar / pivot debate, but wherever they run together the T-bar car is always faster on carpet. Maybe those who do make the pivot car go well (eg, Cleveland and Snowbirds) have some secret that they don't share with us, but for the average Joe, a T-bar car is easier to set-up, and faster.
You are kidding me....right???? On carpet,my ck is faster FOR ME, than my t-force, with the same speedos,motor,batts,servos, & tires.
__________________
Got Droop???
Speed Passion....Speed Power....Serpent America/Desoto Racing.
burgboyz is offline   Reply With Quote
Old 01-26-2006, 04:50 PM   #17106
Tech Apprentice
 
Join Date: Apr 2005
Location: Cincinnati, Ohio
Posts: 92
Default

Something I experienced and have noticed with others is that with the Ck, newer racers seem to have about 5 good minutes and then start struggling with the car getting loose, those that run the T-Fouce have not had this problem.

I am still fairly new to the 12th scale scene as this is my second year of racing it indoors on carpet, but I feel like the T-Fource has been easier for me to run from one week to the next without the issue mentioned above.

I don't know why some of the guys have this problem or what the cause is, but for me, switching to a T bar car has helped a lot. At some point I would like to get a link car again and see how i do as my drving has improved quite a bit over the last year.

Greg
Greg45231 is offline   Reply With Quote
Old 01-26-2006, 05:03 PM   #17107
Tech Master
 
timmay70's Avatar
 
Join Date: Dec 2003
Posts: 1,702
Trader Rating: 5 (100%+)
Default

Quote:
Originally Posted by SlowerOne
I'm not sure about the T-bar / pivot debate, but wherever they run together the T-bar car is always faster on carpet. Maybe those who do make the pivot car go well (eg, Cleveland and Snowbirds) have some secret that they don't share with us, but for the average Joe, a T-bar car is easier to set-up, and faster.
I'd like to see the data back that up. A person's tuner/driver ability is what it's all about. We have some top notch drivers at our track, some running t-bars, some running links. They are always neck and neck. I just prefer the Rev4 over the t-bar.
__________________
Speed Merchant Rev7, Tekin, TQ Racing (wire), Team Tamale
RC Excitement - Buy where you race, support your local tracks.
ROAR #105242
timmay70 is offline   Reply With Quote
Old 01-26-2006, 05:03 PM   #17108
Tech Regular
 
Join Date: Feb 2004
Location: somewhere in the north of england
Posts: 347
Default

Quote:
Originally Posted by CypressMidWest
True that in the Automotive world, this is not truly a live axle, but is always referred to as such in the R/C world.

Unftalented Auto/Mechanical Engineers who are without a clue when it comes to R/C Veortunately fullscale engineering principles do not always equate well to the r/c world. I know many very hicle Dynamics. In actuality, the T-bar, or the link system is what deals with bumps on the track. It's not theory, it's fact. On a bumpy track you can actually watch the cars work, and see the suspension in action. I've been doing this for quite a while and have had cars with various rear suspension designs, and each has it's own strengths and weaknesses, but each also readily displays it's charcteristics on the track. I prefer a car with little to no chassis flex, that can be tuned separately fore and, side to side. I understand that the center shock primarily controls fore and aft weight transfer, but oddly when you soften it up, it absorbs bumps better.
Plus i hate to say this but yank tanks haven't evolved supension design much since the 60's or should i say pre war, but they are now catching up like with the caddilac sts it actually handles shame about the interior quality. The chrysler 300m look nice but it still using archaric supension as well as the ancient Hemi. It also a shame about the mustang nice looking car shame about the handling and the leaf spring live axle.


T-bar a torsion springs.

In the new 2006 model civic you will find that it uses a torsion beam rear end. It was chosen becuase it is lighter low cg and cheaper than using a mutilink rear end setup and NVH is lower than independant rear supension.
Also look up cars using de dion setup or lotus 7 replicas.
Also use in all f1 cars.

Link cars rear ends
Common in ford serrias used to good effect as an IRS rear end, commonly salavaged for current crop of kit cars. Due lack of MK1 Mk2 escort Live axles.

King pin front ends
Similar supesion setup to a 1/12th car, morgan 4+4 uses a de dion rear end and a king pin front supension. So did a lot of 1930 cars such as the aston martins and american fords 32 coupes etc (called a suicide front end).

Reason why it isn't used is high maintenance more effective way of providing spring damping (macpherson struts) NVH, Lighter to use struts production costs and packaging. These don't come into account in rc racing and resonace bounce.

Go Karts are very similar in term of how they work in terms of using flex to generate grip and turn in corners yes in know the don't run a diff but,they are faster using a locked axle, our behave like an Limited Slip diff any way.

Back to why flexy works is absorbs the impact energy of the force of the bump pushing the wheel upwards. Stops the kingpin being over loaded by the bump resonace and allows you to run the supension stiffer, best to think of it as a soft spring damper that can cope with the surface impefections.

Also it is not making the supesion inconsistant, it is flexing to a position that wheels can keep in contact with the road surface.
Setting the supension softer causes the car to understeer as you allowing a high roll rate of the polar moment of inertia or weight transfer.
Weight transfer is biggest when there are large accelarations on the polar moment of inertia causing the mass to transfer such as braking and accelarating and changing direction. Which in turn load the supension.

Small pitching movements won't be to allow the supension to move but will lift the whole chassis up. Like going over a speed bump or an ramp. This due to the low weight of the car the upward wheel reaction being greater than the down ward wheel reaction. newston law of motion everthing has an equal and opposite effect.

Constantly doing this causes the car to skip over the bumpy surface, which causes the car to lose speed by being in the air or the chassis grounding out. Having give in the chassis stop this happening, as it tries to create an equal downward wheel reaction to the up ward force.

This is why currents F1 cars can't run at some of the old race track cause they are not billiard smooth and why a lot of the tracks have gone under major refurbishment.

Also car dynamics are applicable to rc dynamic if you remember a 1/12 will pull up to 6gs laterially in a corner.

Last edited by Smoking motor..; 01-26-2006 at 05:19 PM. Reason: Grammer and spelling an improved explanation
Smoking motor.. is offline   Reply With Quote
Old 01-26-2006, 05:11 PM   #17109
Tech Regular
 
Join Date: Feb 2004
Location: somewhere in the north of england
Posts: 347
Default

Quote:
Originally Posted by jasons56
Its amazing to me how many "full size" automotive engineers are clueless about "full size" PERFORMANCE dynamics. Its no surprise many don't have a clue about RC dynamics.
I had a aged college Mech Eng Professor actually claim that it was impossible for his 4wd Carrera to get beat by my 56' Chevy in a drag race. Because 2 tires carrying 50% of the weight and 100% of the traction could not possibly provide as much acceleration as 4 wheels doing both. Of course, that WAS considered automotive truth when HE was an undergrad. At one point it was even taught that racing speeds would hit a brick wall at 1 G, because no tire could grip more laterally than the weight on it. This was before anyone was using downforce as well.
Took me 3 semesters to actually get a race out of him. He beat that poor Porsche so hard it made me cringe. Bwahhahha. I guess he had never heard of a wheelstand either! Its amazing how open headers put the fear of God into those un-initiated with the racetrack.

Porsche would have won if power to weight ratio was the same, and the rear engine bais would increase forward traction of the car also the porsche only transfered a max of 2% of the power to the front wheels, and your telling me he was a professor.!!! it goes to show it still all down to the driver.
Smoking motor.. is offline   Reply With Quote
Old 01-26-2006, 05:18 PM   #17110
Tech Champion
 
JayBee's Avatar
 
Join Date: Mar 2004
Location: 12TH-MAN COUNTRY
Posts: 6,803
Trader Rating: 31 (100%+)
Default

Quote:
Originally Posted by Smoking motor..
Porsche would have won if power to weight ratio was the same, and the rear engine bais would increase forward traction of the car also the porsche only transfered a max of 2% of the power to the front wheels, and your telling me he was a professor.!!! it goes to show it still all down to the driver.
We can't go on 'IF's', as is... the PORSCHE lost
__________________
R C 3 G R A F I X _ F U S I O N . G R A P H I X _ S E A T T L E - R/C - R A C E R S _ E M E R A L D C I T Y R C . C O M

A E - 12R5.2 _ S M - REV8 PRO
JayBee is offline   Reply With Quote
Old 01-26-2006, 05:25 PM   #17111
Tech Regular
 
Join Date: Feb 2004
Location: somewhere in the north of england
Posts: 347
Default

But i've seen a holden monaro ( pontiac g60) get eaten alive by a 997 model 911 carrera 2. Yes it was on a beach but prove how much traction you get from a rear engined car.

You guys should get hold of top gear. it will educate you in car handling.
Smoking motor.. is offline   Reply With Quote
Old 01-26-2006, 06:09 PM   #17112
Tech Elite
 
Mason's Avatar
 
Join Date: Oct 2004
Location: Ocala, Florida
Posts: 4,576
Default

I hope the CRC site is updated tomorrow.. in any case, which # is their D Ring Big Diff axle.. basically I purchased a BMI conversion, because i can't wait, and i'm looking to mount up a whole rear axle assembly. Silver of course. Does the diff axle come with hubs? I didn't think it does but who knows.. *shrug*

While i'm thinking about it.. does anyone have any complaints about crc damper tubes?

Any info is appreciated
__________________
Mason McCombs
NewRed Hobbies & Indoor Facility
Off-Road, Dirt Oval, Crawlers & Pullers
Mason is offline   Reply With Quote
Old 01-26-2006, 06:14 PM   #17113
Tech Apprentice
 
Join Date: Apr 2005
Location: Cincinnati, Ohio
Posts: 92
Default

CRC's damper tubes are good but you need to ca the the ends on the tube and the threaded rod on the other end for the piston or they will wiggle loose.

Greg
Greg45231 is offline   Reply With Quote
Old 01-26-2006, 06:16 PM   #17114
Tech Lord
 
protc3's Avatar
 
Join Date: Jun 2003
Location: Spring Hill,Florida
Posts: 10,813
Trader Rating: 13 (100%+)
Default

mason,

come down to B and B this weekend.i have something for you.
__________________
Jason Breiner
BMI Racing
Team Associated
J Concepts
protc3 is offline   Reply With Quote
Old 01-26-2006, 06:21 PM   #17115
Tech Addict
 
biker's Avatar
 
Join Date: Apr 2002
Location: Green Bay, Wi
Posts: 725
Trader Rating: 1 (100%+)
Default

Hey guys, I've looked at some of the setup pics on this thread, and was wondering what expert's thought is on servo positioning. In the past, I have always gone by the rule that if you're running the old-school front end, you run the servo flat on the chassis. If you're running the assoc. style front end you use the angled mounts...

I've seen them both ways on here, and was wondering what your thoughts are regarding the 'correct' position.

thanks!
biker is offline   Reply With Quote
Reply

Similar Threads
Thread Thread Starter Forum Replies Last Post
New to the forum mig rod Electric Off-Road 1 01-05-2008 05:23 PM
hi i need help and im new to the forum racer4 Rookie Zone 4 01-21-2007 02:37 PM
Why is this forum listed under the On Road Forum? sport10 Onroad Nitro Engine Zone 0 01-11-2007 08:06 AM
Forum Changes... futureal Wisconsin & Illinois Racing 3 10-28-2002 09:26 PM



Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are Off



All times are GMT -7. It is currently 04:44 AM.


Powered By: vBulletin v3.9.2.1
Privacy Policy | Terms of Use | Advertise Content © 2001-2011 RCTech.net

SEO by vBSEO 3.5.0