Serious problem on 1/18 tires.

[xl-racing]

1/18 FRONT TIRE PROBLEM
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I really serious help. Its been a year been playing 1/18 both on carpet and smooth outdoor pavement i tought this worn out stuff is a normal for front tyre but seems that among our racer i have most problematic encounter. I'm runing HBX 1/18, NRX-18 and M-18. All have same problem on the front tyre. After 1 hour runing around carpet or outdoor smooth carpark track the inner side front tire both left and right will have tearing lines nearby sidewalls of the tire. I suspected it have high "G"s upon cornering.


All my 1/18 model uses Castle SideWinder brushless on 6800KV and 4200KV with 2S lipo. I'm not harsh when it comes to cornering. I always made gentle turn around the corner with no harsh push on the throttle.

Run on 0 degree toe-in and used range 0 to 1.5 degree camber on adjustable and non-adjustable turn buckle "A" wishbone. Caster/angkerman is used between 3 degree and 6 degree. After several setup all doesn't seems to save the tire from being torn out on inner section.


Below attached are photos of torn tires. You'll notice the inner side develop a line of weak spot which result tearing in a short run. For foam tires they worn out evenly flat, but for rubber tires including stock ones the have extreme problem even at low speed. Each tires lasted max around 2 hours of run on the track either both indoor carpet or outdoor race track.

My car already have low CG setup with all lightweight parts and carbon chassis, stock dogbone. Servo, ESC placed as flat as possible to avoid rolling and lower the CG point. have 50/50 weight distribution on overall chassis. The car handling was perfect straight and hardly dirft on dry surface. Everthing was perfect except the tyres. I've already spent more than $100 buck a week for front tire replacement with atleast 3 sets of front savagely beaten in two hours of run.

Where did i missed? Can't find any solution to the problem.
Would appreciate if any 1/18 guru out there could solve this problem.
Thanks.

Summary of 1/18 setup
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Chassis: M18/HBX/NRX-18 (all 150mm)
ESC: Castle Creation- SideWinder with 4200KV and 6800KV
Batt: 2s 1800mah lipo (30c)
Differential: All stock gear mesh (smooth/no binding/ perfect slip/ 2 way)
Differential power distribution: 60% (front) + 40% (rear)
Spur: 36T
Pinion: 22T
Overall terrain: Smooth/no binding/ perfect)
Chassis weight distribution: Perfect 50/50
Runtime on 2s 1800mah lipo: 70 minutes (4200KV motor) / 30 minutes (6800KV motor)

Steering component:
-M11 2.4Ghz
-Hitec HS 225MG

Front setup:
Caster angle: range 3-6 degree
Camber angle: range 0-1.5 degree
Suspension spring: Stock medium
Toe-in: 0 degree

Rear setup:
Caster angle: 0 degree
Camber angle: 0 degree
Suspension spring: Stock medium
Toe-in: 1.5 degree inwards

The problem Tires (front):
Compound material: Rubber
Thread: Stock slick/ Stock threaded grip/ Medium + soft slick Atomic
Installation: Hex and hub slot.
Shape. Flat
Inner foam/sponge: yes

Track driven:
Circuit terrains: Normal floor carpet race/ outdoor smooth carpark surface painted with grippy paint for r/c racing.

Circuit type: Segmented/sectional touring tracks with medium high speed approach and low speed sharp cornering.



Photos:
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[PierreV]

At first glance I thought it was the body causing the ridge. However I then noticed it's on the inside. Strange. However, what's the make of those tires? I don't recognize them but all your tires are the same make so...Does everyone else there use those tires? Have you tried xray tires or GQ Tires? Could it be cheap falty construction for those foams?

[all4fun]

You're not using laquer thinner on those tires for traction compound, are you? Just kidding!! LOL.....judging by the appearence of the wheels in your pics, it doesn't look like you are using XRay tires and wheels. I've been using the M18 Pro wheels/tires since they were 1st available (2 to 3 years now) and haven't had any problems since day one. You may want to give them a try sometime....you'll be happy you did. BTW, I use Paragon traction compound on all of my foam tires. Works real good. Good luck.

[xl-racing]

Thanks for the reply guys,

Brands of tires used include Atomic, GPM, Xray, NANDA, old kyosho stock and other unknown type. They all have same level of wear and tear. All of the have flat slick surface and some have grip threaded for outdoors. Worn out at same rate to unrecognisable feature. The outerwall seems to thin and make round edge but the inner side wall facing the center chassis doesn't worn much as if it says vertical resist flex.

I usually break-in the tyre with few round of slow lap run to warm it up and leveled the surface to get traction. On GRP Racing foam tyres front usually worns at very even and leveled surface but rate of worn out is faster than rear. I dont see an indication of understeer or oversteer.

At first i suspected it maybe my camber setting but i don't see how much different it can void such problem after changing from 0 to max 3 degree.

Is it possible the stock tyre liner/sponge didn't do good work?

or

The square edged tyre with flat surface is a bad choice compare to HPI style round edged tyre?

As for laquer looks at the edge of the wall its a CA glue which i use to glue back ripped out wide wall to avoid side "G"s tear off.

[sLaSh It UPP]

that is the weirdest thing i have never ripped foamies like that on carpet

[801xthawaii]

i thought they were from the body too until i seen where the grooves are too
i run a mamba 8000 motor with a 3s lipo on asphalt and concrete and
haven't done that to my tires
thats pretty weird

[PierreV]

How about some pics of the car with faulty tires on. Include some shots with body as well...May give a hint.

[duneland]

That's pretty common when running rubber tires. The contact area is moving over in corners causing a slight 'fold'. That folded area wears out quickly. Switch to foams. If you were running 1/10 sedan, you would have several different tires/inserts to try. A firmer, molded insert would help, as would a belted tire. Don't think you can find those options for 1/18. Just go to foams and problem solved. Cheaper and less hastle anyway (not to mention FASTER).

[duneland]

I noticed that you have run some foams, but experienced rapid wear up front. That could be a front diff issue. If you run a spool or very tight front diff, you may be getting a lot of skidding on the front tires, causing the excessive wear. How the heck do you get a hs225 into an m18? That would not leave much room for the other stuff..

[Bigcheese]

If you don't want to change tires, I would try less caster. The tire will be flatter going into the turn. I would also try less camber. Try it & see.

[AWDdude]

its gotta be rubbing on something when the wheel is turned

[Tpg racer]

Pic 3 is the most obvious one... it looks as if you put a X-acto knife onto the tyres while running it at full speed... super clean cut...

Something must be cutting the tyres while running... the ridge is very deep and obvious...

It give you that "hmmmppphhh" thinking.....

[Hide]

When you are turning are you hitting the body?

[Ed Anderson]

Originally Posted by duneland

That's pretty common when running rubber tires. The contact area is moving over in corners causing a slight 'fold'. That folded area wears out quickly. Switch to foams. If you were running 1/10 sedan, you would have several different tires/inserts to try. A firmer, molded insert would help, as would a belted tire. Don't think you can find those options for 1/18. Just go to foams and problem solved. Cheaper and less hastle anyway (not to mention FASTER).

Thats exactly whats happening... very common in 1/10 scale. When in a corner all the rubber gets pushed to the inside and you are riding on a 1/8" ball/fold. It wears out fast and makes a perfect ring around the tire.