9 replies to this topic

[Steve Deiters]

"Back in the day" it was viewed that a track was for rubber tires that's what you ran.  If you ran silicone or White Circle tires that is what you ran on the track.  You didn't mix them. 

 

The theory was that there were little silicone "marbles" that resulted as the tires wore.  The marbles could never be washed away.

 

With modern silicones, not mid-'60's formulas, is this still true?

 

Not favoring one or the other just thinking out loud.

[MattD]

Steve, I used to not believe this, but we run silicone exclusively.   Some old silicones, mostly new coated.    You can see the silicone  "oil" buildup on the track.,   The grip is fantastic.    Very few sponge tires will grip at all on this.    Urethane also slides around a lot more than the silicone tires.    Seems to me that this stuff doesn't mix well,    

 

We used to run silicone at the commercial track, but were only allowed to run the nite they cleaned the track.   Guys complained about running sponge the day after we ran.    They cleaned the track when we were done and sprayed more stickum on the track so sponge would grip..   It is nasty stuff and creates really dirty track.   I do believe a steady diet of silicone  inhibits grip by other rubbers.

[MSwiss]

I'm starting this thread so I can merge a few posts out of The Parts Counter.

[MSwiss]

Matt, I think your comment could qualify as one that should have a YMMV addendum.

 

Slot track surfaces vary wildly, from one to another, both in type of paint used, and how it was applied.

 

Also the mix of the spray glue, if it has some applied.

 

We use to race silicone tired Manta Rays, every Saturday, for a few months, at CR, on the same night we raced much faster foam tired cars, directly afterwards.

 

I don't remember any complaints during the foam rubber tire races.

 

We discontinued the Manta Ray races because they became a battle of who had the right silicone tire.

 

If you had old hard AJ's, it was fun.

 

If you had silicone coated sponge, from Protrack, you didn't have fun, because you hopped and got passed a lot by the AJ's guys.

 

We probably should of tried narrowing the Protrack.

 

The other, non related issue was that we were starting to break the fragile Manta Ray guides, running through the esses, and replacement guides weren't something you could buy off of the wall.

 

Back to tires, at the race, the top 3 cars had 3 different types of tires.

 

Speedway silicone, Ortman urethane, and some sort of sponge rubber Dave Crevie mounted up.

 

Despite the track having mostly sponge rubber, typically running on it, Dave Crevie's sponge tires were easily the worse.

 

He was still very fast, but it required some finesse with his trigger finger, accelerating out of turns.

[Pappy]

We've gone through this argument locally. Some think the silicones leave a film on the track that hurts the foam tires. When you clean a track you always have to glue it to get any traction with foam tires. It's just the opposite with silicones, we have to stop and clean our tires periodically during the race on long runs. Just a little dust or carpet fibers will make the track slick for silicones. 

 

At one guy's house that we race at he has never cleaned his track since we started running there years ago. His track surface is painted gray but it looks like it was painted black. He doesn't like us to run silicones anymore because he thinks it puts a film on the track and ruins it for foam. I think what is happening is the silicones are polishing the rubber on the track and making it slick. The silicones run great on it. But he did find out that he can just spray another coat of glue on the track and the problem is fixed for foam tires.

[MattD]

Mike, you are right, there are other factors that  play into this.     We have seen the coated sponge (on a glue track)   can bite too much and chatter and jump and  not  have a nice slide in the corners.   So much stuff that can effect this.   My track is gray and it has silicone tire burn/tracking all the way around.   No other tires have ever been run on it.   I do not clean the track to remove this residue.   The paint is latex semi gloss.    I use a painters tack cloth to gently wipe dust away prior to racing.   We clean tires a few times during the evening.   I have a spray bottle with alcohol/water mix that is sprayed on a cloth and tires are rolled over it and then rolled over a dry cloth.   Dust is pretty minor as this building stays closed up  all the time and has no airflow inside.

 

As a kid our local raceway allowed any tire to be used, there was no glue back then.,    Silicones were the tire of choice and everybody gave up on sponge or  rubber tires from a kit build.. 

 

I like a clean track without glue.    

[slotbaker]

My limited experience with silicone tires was when a visitor ran his silicon clad cars on blue lane for social running prior to our club race night.

 

Generally the track got a light spray glue when needed, and most club nights we just ran as found.

 

That night, blue lane was undrivable (compared to the other lanes) for our S16D flexi cars with foam.

 

We came to the conclusion that the silicone tires scrubbed the surface clean of our light glue and rubber build up.  We could clearly see that the surface was cleaner, but didn't think that there was any silicone residue left behind.

 

If the whole track had silicone tires run on it, then the surface would likely be less grippy than normal, and maybe wouldn't have been as noticable.

 

So we didn't allow silicone tires after that.

[Mr. M]

We ran little puddles of water on the main straight with silicones. Cleaning problem solved!

[MSwiss]

When a racer asked me earlier tonight, to test his new car, I wondered for a moment, if the vintage race on Saturday had affected the traction conditions, which prerace, IMO, were almost perfect.

That new build wasn't terrible, but I did consider it loose.

Then he had me try his proven car, that I had hot lapped to record times, a week or 2 earlier.

I was able to match those times with little effort.

I went to one of the faster turns, and was able to put my finger print in the sticky rubber buildup.

So if any rubber was scrubbed off by the silicone, it didn't affect lap times.

My surface is a Sherwin Williams, water based, 2 part epoxy, marine coating.

The color is Graphite, a super dark grey, or light black , "color", that is ideal for camouflaging rubber buildup.

I wish I had used it on the King, instead of light gray.

[Dave Crevie]

At Chicagoland we did run hardbodies after the vintage race. I heard no complaints about grip. The problem I had was not related to

silicones or urethanes being used by other cars. I had mounted very soft natural rubber donuts on my car, thinking the light magnesium

chassis would need all the grip it could get. But being as tall as they were to get ground clearance, they were just too bouncy. 

 

I regularly run my old cars on that track, both with silicones of various manufacture, and rubber tires. I have found no problems relating

to tires.