Jump to content




Photo

Tires: composition, width trimming, and general questions


  • Please log in to reply
19 replies to this topic

#1 Shruska55

Shruska55

    On The Lead Lap

  • Subscriber
  • PipPipPipPip
  • 352 posts
  • Joined: 05-November 18
  • Gender:Male
  • Location:Frankston, TX

Posted 24 August 2020 - 10:50 PM

All

 

As I get further back into slot racing again, even with the COVID, I'm beginning to discover more about the changes in the products from my youthful days 50 years ago. I've read many posts about folks truing tires and understand the reason behind that. In fact, I have done it to great effect and thank the Slotblog posters who helped out.

 

The general questions are these:

 

1) What type of track surface might I use a medium or soft rubber sponge versus a firmer one? Back in the day all we had were American tracks. Today...lots of track surface options.

 

2) IRRA rules state that super glue and nail polish is allowed on front tires. I've heard tell of folks using those on the inside of tires to firm up the side to side flex in the corners. I assume this it to improve handling, but with a properly setup and weighted car as part of that, is this necessary or would tire compound choice be a better option?

 

3) I've also seen posts regarding overall width of a tire. I'm assuming that this too is a cornering improvement option. Too much tire, too much bite, yes? Or is there some other reason for narrowing the tire?

 

4) Any general info on tires and why I would choose one over another.

 

Thanks, in advance,

 

ScottH


Scott Hruska
East Texas




#2 Sean Mikuen

Sean Mikuen

    Backmarker

  • Full Member
  • PipPip
  • 71 posts
  • Joined: 09-March 15
  • Gender:Male
  • Location:Madison Heights, VA

Posted 25 August 2020 - 01:16 AM

The use of nail polish or super glue for the front tires is to reduce the amount of grip as much as possible. In forms of slot racing where the fronts are required (or required to touch), you can get adverse affects if there is too much front tire grip.
 
Narrowing a tire is a good way to do fine tuning of the grip. I recently saw a post where a racer was doing alright, but the car didnt "power slide" at all, but rather sticking like it was on rails. After narrowing the tires, lap times went down and he was able to corner quicker. I believe the idea of power slides being quicker is because when you have that bit of slide, your car's flag is being pushed into the groove with the track, whereas if if was sticking like its on rails, it would be pushing the car tangently to the track.

 
Now 1 and 4 are pretty much the same questions. With the best answer of it depends. I have been doing testing at my local raceway, and on different days, diffefent tires will preform better.

Days where the track is cleaned, and no glue is applied will usually want softer tires, until it builds up a grove and then you can start using a medium or hard tire.

But on days where the track has been glued, if you run anything shy of hard, youre stopping in every turn.

Now in general, you want to run the hardest tire you can, without it just slidng all over. And once you find that tire, if it slides just a bit in turns, youre golden.

Now there is also hub diameter too, the larger the hub the harder it gets too. A .615 hub tire will be harder than a .400 hub tire. And also hub material, a plastic hub will have more flex than a metal one, making if feel softer.

But thats just what ive found with trying things out. The second best thing to do is try it out yourself, and the best is to ask the fast guys what they use because they probably already did the work
  • Shruska55 likes this
Sean Mikuen
"There are two kinds of people in this world. Those who race slot cars, and those who lose."

#3 tonyp

tonyp

    Grand Champion Poster

  • Member at Peace
  • PipPipPipPipPipPipPipPip
  • 15,325 posts
  • Joined: 12-February 07
  • Gender:Male
  • Location:Sanford, FL, land of lizards and big roaches

Posted 25 August 2020 - 07:46 AM

Nail polish on retro fronts is a no no. Makes car worse.
  • Pete L., Tim Neja and crazyphysicsteacher like this

Anthony 'Tonyp' Przybylowicz

5/28/50-12/20/21
Requiescat in Pace


#4 idare2bdul

idare2bdul

    Grand Champion Poster

  • Full Member
  • PipPipPipPipPipPipPipPip
  • 5,799 posts
  • Joined: 06-March 06
  • Gender:Male
  • Location:Garner, NC

Posted 26 August 2020 - 03:46 PM

Lots of good advice. If possible get a local mentor to advise or help you. If at all possible buy from your local track. That can be a problem if they don't stock or order what you need in a timely manor. Try not to have last minute orders. Most racers come with at least 2 different compounds or tires. 

Your biggest speed secret is between your ears. You need to learn to race. It takes time and practice and actual race time. Most new racers worry too much about equipment and not enough on practice and learning.


  • Uncle Fred, tonyp, Tim Neja and 1 other like this
The light at the end of the tunnel is almost always a train.
Mike Boemker

#5 John Streisguth

John Streisguth

    Johnny VW

  • Full Member
  • PipPipPipPipPipPipPipPip
  • 5,638 posts
  • Joined: 20-November 08
  • Gender:Male
  • Location:Bangor, PA

Posted 27 August 2020 - 07:40 AM

Nobody runs coatings on the fronts of retro cars.  Seems it was an idea from when everyone ran super hard fronts in the early 70's.  


  • Tim Neja and crazyphysicsteacher like this
"Whatever..."

#6 Shooter7mustang

Shooter7mustang

    On The Lead Lap

  • Full Member
  • PipPipPipPip
  • 214 posts
  • Joined: 23-December 14
  • Gender:Male
  • Location:Oklahoma City Oklahoma

Posted 27 August 2020 - 11:08 AM

Nobody runs coatings on the fronts of retro cars.  Seems it was an idea from when everyone ran super hard fronts in the early 70's.  

Actually lots of guys run coatings on the fronts.


Kevin Myhaver
 
Bad Dog Racing
Color Me Gone
 
Romans 1:16 "... for I am not ashamed of the Gospel"


#7 Uncle Fred

Uncle Fred

    Checkered Flag in Hand

  • Full Member
  • PipPipPipPipPipPip
  • 1,367 posts
  • Joined: 29-September 06
  • Gender:Male
  • Location:Northlake, TX

Posted 27 August 2020 - 02:43 PM

I'm waiting for some really insightful information.......  What do people feel about say, rounding outside edges, inside edges, rubbing tire treatments in, etc?

 

And yes, I feel a lot of racers need to spend more time practicing, especially on the gutter lanes.


  • Tim Neja likes this
Fred Correnti

#8 Ramcatlarry

Ramcatlarry

    Posting Leader

  • Subscriber
  • PipPipPipPipPipPipPip
  • 2,904 posts
  • Joined: 08-March 06
  • Gender:Male
  • Location:St Charles, IL 60174

Posted 28 August 2020 - 10:41 PM

My take on nail polish on the fronts is that it is needed when you cannot have independent rotating front wheels like on 1/8" axle FCR and other hardbodies.  It does work well on 1/32 Scalex/Carrera type cars.

 

Some oval racers will narrow one rear tire to get some drift if the bite is too jerky.  OR use a different compound....or diameter for stagger....


Larry D. Kelley, MA
retired raceway owner... Raceworld/Ramcat Raceways
racing  around Chicago-land

 

Diode/Omni repair specialist
USRA 2023 member # 2322
IRRA,/Sano/R4 veteran, Flat track racer/MFTS

Host 2006 Formula 2000 & ISRA/USA Nats
Great Lakes Slot Car Club (1/32) member
65+ year pin Racing rail/slot cars in America


#9 Eddie Fleming

Eddie Fleming

    Posting Leader

  • Full Member
  • PipPipPipPipPipPipPip
  • 2,751 posts
  • Joined: 27-April 14
  • Gender:Male
  • Location:Fayetteville, GA USA

Posted 29 August 2020 - 08:57 AM

Just for clarity on Larry"s point.The only reason you can't get independent rotation on front wheels is if the rules don't allow it. 


  • Tim Neja likes this
Eddie Fleming

#10 Phil Smith

Phil Smith

    Posting Leader

  • Member at Peace
  • PipPipPipPipPipPipPip
  • 3,582 posts
  • Joined: 03-November 07
  • Gender:Male
  • Location:Irving, TX

Posted 29 August 2020 - 11:49 AM

What do people feel about say, rounding outside edges, inside edges...

 

Personally: I never round the edges.If I was going to round anything, it would be the inside edges, but I don't.


Phil Smith
???-2/31/23
Requiescat in Pace

#11 crazyphysicsteacher

crazyphysicsteacher

    On The Lead Lap

  • Full Member
  • PipPipPipPip
  • 361 posts
  • Joined: 04-March 12
  • Gender:Male
  • Location:NJ

Posted 29 August 2020 - 06:58 PM

Round the edge on every tire. It helps to let the car slide in the corner.

For fronts, you want the hardest tire that will roll with the least resistance but i has to give for suspension in the corners. Too hard of a tire will result in more deslots. If you run a flexi with fronts, harder tires will act more like running the car on the chassis.

As to tire hardness, it is up to the track. Start soft and go harder. Run the hardest tire you can. The hub even determines this. You need to make sure that you have enough forward bite but the car needs slide in the corner. You may have a car that is planted with a soft tire but is faster with a harder tire because the soft tire bogged you down. The only way is to have multiple sets of tires all prepped the same to be able to compare.

Sent from my Nokia 7.1 using Tapatalk

Chris Wendel
Silver Side Down Racing
Silver Side Down Graphics

​The Race Place Retro Crew member

"Failure teaches way more than success. It shows what does not work and what to never do again, again..." 🙊🙈🙉  


#12 SpeedyNH

SpeedyNH

    Old Engineer

  • Full Member
  • PipPipPipPipPip
  • 736 posts
  • Joined: 18-July 15
  • Gender:Male
  • Location:Cow Hampshire

Posted 31 August 2020 - 05:33 PM

then i guess i won't talk about the time i tried 900 wide tires on my eurosport when the .810's i was running out of were too tight and it loosened the car up. 

 

i agree, the zero-grippiest fronts you can find (or make) will scrub off less speed in the corners, independent (which helps) or not. and i sure do miss those 60's hard vinyl tires! except for all the noise they made. 


Steve Lang

#13 Sean Mikuen

Sean Mikuen

    Backmarker

  • Full Member
  • PipPip
  • 71 posts
  • Joined: 09-March 15
  • Gender:Male
  • Location:Madison Heights, VA

Posted 31 August 2020 - 07:22 PM

then i guess i won't talk about the time i tried 900 wide tires on my eurosport when the .810's i was running out of were too tight and it loosened the car up. 

 

i agree, the zero-grippiest fronts you can find (or make) will scrub off less speed in the corners, independent (which helps) or not. and i sure do miss those 60's hard vinyl tires! except for all the noise they made. 

that is because the contact patch of the tire does not affect the amount of friction. more than likely, the .900s were a bit harder than the .810s, or possibly the extra weight was able to overcome the frictional force in the turns.

 

the reason that contact patch has no affect is because F=uN, or the force of friction is equal to the coefficient of friction times the normal force, where the normal force is the force on the object that is perpendicular to the surface the object is on. hence why if you start in a bank, the car may slide down. it is because the normal force and coefficient of friction are not able to overcome gravity. 


Sean Mikuen
"There are two kinds of people in this world. Those who race slot cars, and those who lose."

#14 SpeedyNH

SpeedyNH

    Old Engineer

  • Full Member
  • PipPipPipPipPip
  • 736 posts
  • Joined: 18-July 15
  • Gender:Male
  • Location:Cow Hampshire

Posted 31 August 2020 - 07:27 PM

the contact patch of the tire does not affect the amount of friction? so in extreme cases, i could run maybe .001 wide tires, for example? (if i could keep them from bending over) or four foot wide tires, given the same compound and diameter? Lol  (i'd have to put a bigger arm in for that one!) 

i was really only trying to throw a joke wrench in the works. i do appreciate the science, though. 

 

i'm still to this day trying to figure out how that worked, which is why i threw it in there. i had inconclusive results trying it later on other tracks, but it tended to act the other way, and i often saw people narrowing their tires to loosen it up.  i was still trying to fully marry the science to the car, but was never able to spend enough time on it. there are still a few things that eluded me. 


Steve Lang

#15 Isaac S.

Isaac S.

    Checkered Flag in Hand

  • Full Member
  • PipPipPipPipPipPip
  • 1,507 posts
  • Joined: 02-September 20
  • Gender:Male
  • Location:USA

Posted 02 September 2020 - 03:35 PM

I've got some tires that are old, hard and cracking and they don't make reproductions and I'd like to keep them original style. Do you guys have any tricks on how to soften old tires? The cracks aren't too deep so I'm not too concerned about those and they are still rather round. The tires will just spin and spin and spin and the car barely goes anywhere and I've added some weight but that didn't do much. 


Isaac Santonastaso

#16 SpeedyNH

SpeedyNH

    Old Engineer

  • Full Member
  • PipPipPipPipPip
  • 736 posts
  • Joined: 18-July 15
  • Gender:Male
  • Location:Cow Hampshire

Posted 02 September 2020 - 04:17 PM

i'm assuming that these are vintage rubber, not foam. one option might be oil of wintergreen, but i haven't tried it.  lacquer thinner might destroy them. 


Steve Lang

#17 James Wendel

James Wendel

    Checkered Flag in Hand

  • Full Member
  • PipPipPipPipPipPip
  • 1,019 posts
  • Joined: 02-June 10
  • Gender:Male
  • Location:Roseburg, OR, USA

Posted 02 September 2020 - 04:51 PM

The best cure for dry rubber is to true them down to fresh(er) rubber.... assuming that you have some diameter to sacrifice.


  • NSwanberg likes this
You can't always get what you want...

#18 Isaac S.

Isaac S.

    Checkered Flag in Hand

  • Full Member
  • PipPipPipPipPipPip
  • 1,507 posts
  • Joined: 02-September 20
  • Gender:Male
  • Location:USA

Posted 02 September 2020 - 07:12 PM

I have sanded them down some and I think they are try to bone. Thanks for the other info Steve.


Isaac Santonastaso

#19 SpeedyNH

SpeedyNH

    Old Engineer

  • Full Member
  • PipPipPipPipPip
  • 736 posts
  • Joined: 18-July 15
  • Gender:Male
  • Location:Cow Hampshire

Posted 02 September 2020 - 07:15 PM

that's what i would have expected. at least mine are, anyway. i haven't heard of anyone who was able to bring them back, but hope springs eternal! 


Steve Lang

#20 MSwiss

MSwiss

    Grand Champion Poster

  • IRRA National Director
  • PipPipPipPipPipPipPipPip
  • 25,614 posts
  • Joined: 16-April 06
  • Gender:Male

Posted 02 September 2020 - 07:26 PM

Are you looking to have the original rubber, or are you just concerned that they are the original rims?

 

If the latter, I have a guy that does a nice job molding silicones on any rim.


Mike Swiss
 
Inventor of the Low CG guide flag 4/20/18
IRRA® Components Committee Chairman
Five-time USRA National Champion (two G7, one G27, two G7 Senior)
Two-time G7 World Champion (1988, 1990), eight G7 main appearances
Eight-time G7 King track single lap world record holder

17B West Ogden Ave., Westmont, IL 60559, (708) 203-8003, mikeswiss86@hotmail.com (also my PayPal address)

Note: Send all USPS packages and mail to: 692 Citadel Drive, Westmont, Illinois 60559






Electric Dreams Online Shop