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 10-06-2009, 03:57 PM   #32371
Tech Regular
 
Lost Aggresiva's Avatar
 
Join Date: Apr 2004
Location: Caledonia, MI
Posts: 255
Trader Rating: 2 (100%+)
Default

Just out of curiosity, has anyone tried the Futaba BLS651 servo in their car? I have tried their other brushless servos and have very happy with them. Been thinking about trying one in the 1/12th scale.

Bill.
Lost Aggresiva is offline   Reply With Quote
Old 10-07-2009, 02:36 PM   #32372
Tech Master
 
GasGod's Avatar
 
Join Date: Mar 2009
Location: Tween a Rock & a Hard Place in Pa.
Posts: 1,259
Trader Rating: 3 (100%+)
Default

Is it frowned upon to run a 13.5/4cell against 13.5/single lipo??
I would think the weight diff would make up for any so called voltage advantage.just wondering if anyone has run into this yet.
Where are the saddle pack lipos--
__________________
F! Metal Militia,VTA NATION--Team SloMoFo
losi 8t,mbx5t,rc8
rc8,Kyosho rb5,SCR
ft4 MT wallet
cyclone;xxx-s;x-rayT2;crc gen xl;bmi 12rrl
GasGod is offline   Reply With Quote
Old 10-07-2009, 02:43 PM   #32373
RAL
Tech Elite
 
RAL's Avatar
 
Join Date: May 2002
Location: Los Angeles, CA
Posts: 2,205
Trader Rating: 59 (100%+)
Default

I know at our local carpet track these are your options for "stock" all combo's are looked at as equal. Don't know if it really is. I'm sure the gurus on here can tell you. I'm curious as well as to how they match up.

27t 4cell
17.5 4cell
13.5 1s lipo
__________________
TEAM ARAI GRIP ● J★STYLE ● P1 BRAND ● RÄLDESIGNWERKS ● FANTOM ● EXOTEK
RAL is offline   Reply With Quote
Old 10-07-2009, 03:18 PM   #32374
Tech Elite
 
Scottmisfits's Avatar
 
Join Date: Jun 2004
Posts: 3,104
Trader Rating: 7 (100%+)
Default

In our local series we are maybe looking at a weight break. Same motor but 795g for 4 cell and 730g for 1 cell.

IIC ran the same track for the last couple of years, from what I understand. When they went to a lighter weight and 1c only this year, the lap times stayed virtually the same.
Scottmisfits is offline   Reply With Quote
Old 10-07-2009, 04:30 PM   #32375
Tech Elite
 
theisgroup's Avatar
 
Join Date: Apr 2002
Posts: 3,191
Trader Rating: 10 (100%+)
Default

be aware that even .2sec a lap difference for 40 laps, that is 8 sec. that is probably close to a lap difference
__________________
yang lai

Team Tamale | Team Tekin | RCAmerica | Speedmerchant | Speedzone RC | EA Motorsports | Ko Propo USA | eXpress Motorsports | Parma/PSE
theisgroup is offline   Reply With Quote
Old 10-07-2009, 04:40 PM   #32376
Tech Master
 
GasGod's Avatar
 
Join Date: Mar 2009
Location: Tween a Rock & a Hard Place in Pa.
Posts: 1,259
Trader Rating: 3 (100%+)
Default

I really wanna see saddle pack lipos--any backyard "engeniering"been done .
like on some helio packs wired in parallel to get the Mah up?
__________________
F! Metal Militia,VTA NATION--Team SloMoFo
losi 8t,mbx5t,rc8
rc8,Kyosho rb5,SCR
ft4 MT wallet
cyclone;xxx-s;x-rayT2;crc gen xl;bmi 12rrl
GasGod is offline   Reply With Quote
Old 10-07-2009, 05:30 PM   #32377
Tech Adept
 
Join Date: Jan 2009
Location: colorado
Posts: 168
Send a message via Skype™ to slotracer577
Default

On the oval track I run the 17.5 4 cell and 13.5 1cell are pretty equal. The 27T is a little slower probably .3 to .4. Might not be fair as the 27T are usually slower drivers.



Quote:
Originally Posted by RAL View Post
I know at our local carpet track these are your options for "stock" all combo's are looked at as equal. Don't know if it really is. I'm sure the gurus on here can tell you. I'm curious as well as to how they match up.

27t 4cell
17.5 4cell
13.5 1s lipo
__________________
Team Epic
slotracer577 is offline   Reply With Quote
Old 10-07-2009, 06:21 PM   #32378
Tech Elite
 
CypressMidWest's Avatar
 
Join Date: May 2003
Location: Central Ohio
Posts: 4,603
Trader Rating: 1 (100%+)
Default

Quote:
Originally Posted by kn7671 View Post
Just better!
If by better, you mean uglier and heavier wheel, with the same rubber, then you're right.
__________________
Team CRC, Access Race Place, US Indoor Champs, CD SUPERPRO, RK Designs, Cypress, Founder and lead instructor of the Ian Ruggles Negative Reinforcement Driver Training Program, enroll now.....
CypressMidWest is offline   Reply With Quote
Old 10-08-2009, 09:30 AM   #32379
Tech Regular
 
Old Tech's Avatar
 
Join Date: Oct 2003
Posts: 436
Trader Rating: 3 (100%+)
Default

Quote:
Originally Posted by GasGod View Post
I really wanna see saddle pack lipos--any backyard "engeniering"been done .
like on some helio packs wired in parallel to get the Mah up?
Speedzone is working on one. Some discussion about the pack here:

Speedzone 3.7v Lipo 4800mAh 30C
Old Tech is offline   Reply With Quote
Old 10-08-2009, 09:38 AM   #32380
Company Representative
 
ammdrew's Avatar
 
Join Date: Feb 2002
Posts: 10,042
Trader Rating: 25 (100%+)
Default

13.5 3.7v does the same laptimes as 13.5 4 cell. So no it is not equal to 17.5 4 cell.... The bigger part of the picture is the corner speed vrs straight speed. Laptimes for 3.7v with the 10% drop in wt gain all the hp loss back in corner speed and run the same laptimes but in a rd course environent it makes for a messy race as if you have similar skilled drivers the flow lines are different through corners and into the straights.
__________________
Team Tekin, Team Scream, Paint By Mike, Team Mölzer Mowery Racing, EA Motorsports, Speedmerchant, TQ Wire

MMR Direct Minneapolis World Class Indoor Race Facility.
On Road and Off Road racing year round.

www.molzermoweryracing.com
http://www.facebook.com/pages/MMR/160679913944205?__req=9

Check out You Tube mmrswracing. Every qualifier and every main uploaded at the end of every race day.
ammdrew is offline   Reply With Quote
Old 10-08-2009, 10:53 AM   #32381
Tech Master
 
RBMike's Avatar
 
Join Date: Jan 2007
Location: Santa Clara CA
Posts: 1,264
Default

Anyone know where I can find a 17.5 Duo2 "in stock"? Seems to be on back-order eveywhere.
__________________
-EMBX6,T8 1400, RX8, 5S Lipo ,Elite-RC, RCM tray
-EMBX6,T8 1350, RX8, 5S Lipo ,Elite-RC, RCM tray
-B44 (Novak)
-ROAR 4 cell rule Blows
RBMike is offline   Reply With Quote
Old 10-08-2009, 11:16 AM   #32382
Tech Champion
 
Scottrik's Avatar
 
Join Date: Sep 2004
Location: Billings, MT
Posts: 6,122
Trader Rating: 238 (100%+)
Default

Quote:
Originally Posted by ammdrew View Post
13.5 3.7v does the same laptimes as 13.5 4 cell. So no it is not equal to 17.5 4 cell....
Testing here showed that with the same gearing a 1s / 13.5 was VERY close to the same as a 4-cell / 17.5. But when we started gearing the 1s / 13.5 up to where it was optimized it was significantly faster than the 4-cell / 17.5 is.

I know the W. Washington guys (Bodine, DuTemple, et al) have decided that 1s / 13.5 and 4-cell 13.5 run together acceptably well. The Fantasy World Summer Sizzler (25th Annual!!) allowed either of these specs and the main proved to be a duel between Mike with a 4-cell car vs. Brian with a 1s car. Bodine made a small mistake early and spent 6 minutes running several seconds behind but the gap was pretty much the same throughout. With 1 minute to go the 4-cell car began to slow noticeably (geared pretty aggressively to keep ahead of the BodineMachine) to near full dump at the end where he won by a second or so. Had the race been even one more lap (heck...one more corner) and Brian would have had him.

Last edited by Scottrik; 10-08-2009 at 01:04 PM.
Scottrik is offline   Reply With Quote
Old 10-08-2009, 12:01 PM   #32383
Tech Master
 
mkdut's Avatar
 
Join Date: May 2006
Location: RC Retired
Posts: 1,961
Trader Rating: 19 (100%+)
Default

[QUOTE=Scottrik;6446629]
Quote:
Originally Posted by ammdrew View Post
13.5 3.7v does the same laptimes as 13.5 4 cell. So no it is not equal to 17.5 4 cell....QUOTE]

Testing here showed that with the same gearing a 1s / 13.5 was VERY close to the same as a 4-cell / 17.5. But when we started gearing the 1s / 13.5 up to where it was optimized it was significantly faster than the 4-cell / 17.5 is.

I know the W. Washington guys (Bodine, DuTemple, et al) have decided that 1s / 13.5 and 4-cell 13.5 run together acceptably well. The Fantasy World Summer Sizzler (25th Annual!!) allowed either of these specs and the main proved to be a duel between Mike with a 4-cell car vs. Brian with a 1s car. Bodine made a small mistake early and spent 6 minutes running several seconds behind but the gap was pretty much the same throughout. With 1 minute to go the 4-cell car began to slow noticeably (geared pretty aggressively to keep ahead of the BodineMachine) to near full dump at the end where he won by a second or so. Had the race been even one more lap (heck...one more corner) and Brian would have had him.
Without a doubt we have proven that they are fairly equal. The 4 cell had more speed down the straight but the 1S with the light weight floats through the infield. You could really tell the weight difference between the two when getting into the corners. It seemed like I was trying to stop a dump truck compared to Brian's car.

And yes Brian would have needed one more corner. My 9 month old cells had had enough.
mkdut is offline   Reply With Quote
Old 10-09-2009, 08:55 AM   #32384
avs
Tech Master
 
avs's Avatar
 
Join Date: Jul 2006
Posts: 1,144
Trader Rating: 2 (100%+)
Default

Quote:
Originally Posted by AdrianM View Post
Please copy and paste this into MS Word so you have saved locally

Building a Diff

I use plain chrome steel diff balls from BMI, IRS, anyone...they are all the same high grade 1/8" ball bearings.

I like to use Schumacher U1301 silicon diff grease or Associated silicon diff grease, the thick type in a plastic cup not the stealth grease in a squeeze tube. Stealth grease is too thin and gets flung out too easy.

The diff balls I buy come in a 100 pack for ~$8. I open the pack over a clean paper tower and dump them out. All diff balls have a coating of oil on them to protect them while they sit on a shelf. I use motor spray carefull to wet them and then roll them on the paper towel to dry them. I then dump them all into the cup of diff grease. I keep them there untill I use them.

When I build a diff I sand both sides of the diff rings with 600 grit wet-dry sandpaper lubricated with a little motor spray untill I see an even finish across the face of the rings. I then clean the rings with motor spray and dry them on a clean paper tower.

Be sure to clean your finger tips with motor spray before touching the diff balls or rings. If you get any bearing oil or traction compound on them from your fingers it will contaminate the diff and mess it up.

I then pluck the diff balls out of the diff grease cup with a small clean flat blade screwdriver and put them in the spur gear. They will carry all the diff grease they need with them. You do not need to put more on the rings. I put a ball in all 12 holes in the outer circle. The inner circle of holes is for the no longer used small diameter "Stealth" diff rings.

Assemble the diff normally but tighten it slowly until you just start to get diff action. If you overtighten it you can dimple the rings and flat spot the balls. Tighten it and check the gear for slipping. As soon as the gear starts to get hard to slip stop.

Mount some tires on the axle. Hold one tire and the gear locked and force the opposide side to turn a few turns. Repeat with the other side. This is called cutting the diff. Cutting the diff smooths out any imperfections in the rings and balls by burnishing them. The diff may have loosened a little from cutting it so readjust it so the gear is very hard to slip (this is tighter than the previous step).

Install a motor and put the car up so the wheel are not touching the table. Run it at meduim throttle and alternatly touch one tire then the other untill it just stops then let go. This will heat up and fling out excess diff grease as well as breaking in the diff. Do this a couple times per side.

Re adjust the diff a final time so it wil not slip and you are done. The diff should be glass smooth. It should spin very freely as if it were really loose but the diff gear should be almost impossible to slip.

If the diff is gritty with new rings and balls replace the outer right side hub bearing.

If the diff is slipping you have some petroleum oil contamination in the diff. Take everything apart and start over after cleaing everything with motor spray.
Some people were having diff troubles last night. Because I found your guidance very helpful, (and the search feature has been goofy) i just relisted it here again.
avs is offline   Reply With Quote
Old 10-09-2009, 10:04 AM   #32385
Tech Regular
 
inconceivable's Avatar
 
Join Date: Jan 2008
Posts: 331
Trader Rating: 3 (100%+)
Default

Thank you for re-posting this !
__________________
"And now the Matador shall dance with the blind shoe maker"
"America is all about speed. Hot, nasty, badass speed. - Eleanor Roosevelt, 1936"
inconceivable 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 11:25 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