I have a very important and technical tire question

[Tb3]

lol actually this is a serious question I've wondered about many times, just never looked into it. I figure everything that can be asked on the internet has been asked many times over but perhaps not this one?

My driveway is concrete but only for about 20 feet out from the garage. The rest of the way out to the road it is gravel for about 200 feet.
So when I pull out the garage for the first ride of the day and my tires are cold, gravel unfortunately sticks to them almost seems like glue, throwing them up into my fenders, under cowl, radiator, etc, making me cringe and cuss as I am one of those that don't want my baby scratched if I can help it I now always just ride over into the grass till I get to the road to minimize it.
Fast forward to when I get back....the tires are good and warm (or usually pretty hot), and I pull into the gravel drive and the little gravel rocks don't stick at all.
How come? We always read about not pushing the tires hard until they've warmed up right? Isn't that because when their hotter, they're stickier? Seems like it should be the opposite result.
Why does this happen?

 

[c10]

That is a fine question sir. however I do not have a answer for this one.

Paging @Mr Brown

 

[Bumblebee]

I watched a video today that explained something about the silica in the rubber and how it reacts to different temperatures and how some tires have larger and smaller silica imbedded into the tire rubber...

Maybe it has something to do with the silica content in your tire?

 

[Tb3]

I watched a video today that explained something about the silica in the rubber and how it reacts to different temperatures and how some tires have larger and smaller silica imbedded into the tire rubber...

Maybe it has something to do with the silica content in your tire?

I have multiple bikes from scooters to cruisers to sport bikes, and it is the same for all them, no matter the tire. Obviously its worst when I pull out with brand new tires installed.

 

[jellyrug]

I have a gravel driveway about 250 ft and then a dirt road with loose sand for about 3/4 of a mile. My tires don’t pick anything up? I ride Pirelli tires.

 

[Bumblebee]

I have multiple bikes from scooters to cruisers to sport bikes, and it is the same for all them, no matter the tire. Obviously its worst when I pull out with brand new tires installed.

All tires have silica in them...could be this...it was only a shot in the dark on my behalf...

 

[WuzzaCBXRider]

Maybe you’re not holding your mouth right....

 

[Tb3]

dang. was thinking surely this is common.
maybe I just have sticky gravel

 

[Mr Brown]

There's something on the floor of your garage that's sticky. Does your car do it too?

 

[Mr Brown]

Cold tires don't pick up gravel, hot (not warm, hot) tires do. Spin your back tire a few turns on the concrete next time and see if it still picks up rocks. I'll bet it doesn't.

 

[Kiwi Rider]

There's something on the floor of your garage that's sticky. Does your car do it too?

I would agree with this theory . .
try placing a towel or a sheet over the garage floor, next time you roll home, ride straight onto the covering and next time you leave, check the tire to see if it is still picking up gravel.
Or . . shift house to a place with a concrete drive all the way to the street.
There, simple fix to the problem.
I have a concrete garage floor, not painted, and a gravel drive all the way (20ft) to the street, sealed road.
Never had a problem like yours.
My gravel is fairly fine grade, size of a pea type stuff, and not very sharp either.
Never thought I'd find myself discussing gravel grades here on this forum lol.

 

[Hayabusa Wannabe]

Guess:: you are running low pressure. Regarding the tire, I do not know much about compounds but I wonder if it is in fact not a hard touring compound.

Theory: The lower the pressure the more the tire is going to deflect or change shape. The weight on the bike and the upward pressure of the rock deflects the rubber so that the rock is embedding in the tire. The contact patch rolls from the ground backwards, and when the weight is no longer on the rock, the deflected rubber pops out and flings the rock at exactly what you observed, both soft aluminum as well as shiny, polished areas of the bike. (How does it choose these areas? Sorry, with my particular background I cannot help with biological sport bike artificial intelligence.)

When warmed up the pressure is significantly higher, the tire is harder and thus does not deflect as much. If I am right and you try using the maximum cold rated pressure, the effect will slow or even completely stop.

Kiwi made a real observant point: His gravel is smooth. That could explain why he never sees this phenomenon. The sharper the gravel, the greater some of the deflection will be. How sharp is yours?

I figure everything that can be asked on the internet has been asked many times over but perhaps not this one?

Before you ever decide not to be inquisitive and ask a technical question, look up the Tom Kyte story of the Oracle Database that slowed down on rainy days. What would your help desk reply if you told them your application was slow on a rainy day? (Non-inquisitive Neanderthals, the lot of them.)

 

[08BusaKY]

They just redid my road (asphalt) and left loose little pieces all over. They stick to my stock tires with recommended air pressure. It throughs them up in my fairing and my oil cooler between the screen and fins. I have to use a vacuum to get them out. Now I go as slow as possible to get off my road.

 

[Bumblebee]

….are you in the garage drooling over your bikes? Drool would be sticky and make gravel stones stick....

 

[Mythos]

I store mine in a a storage unit with a couple hundred feet of gravel road before the highway. Never noticed any rocks getting thrown when I get on the road. I have Metzler CompKs right now. Bridgestone RS10s on my other bike and no rock throwing there either. Rocks do stick when I come back but I barely idle my way in and out of the storage unit lot.

 

[fallenarch]

I don't have a theory why this happens but I do have a solution: Tire Warmers. Lol!

 

[GAmedic]

Eat enough pie and the problem will sort itself out

 

[VIPER]

DEW. In the am the gravel has a thin coat of moisture on it from dew.

 

[Notenoughtoys]

Tb3 I have had the exact same problem since day 1. Running Dunlops on a fine grain limestone driveway around 200' long. Pick up lots of debris heading down the driveway with cold tires and coming back with warm tires nothing sticks. The exact opposite of what I'd expect.....

 

[Tb3]

Tb3 I have had the exact same problem since day 1. Running Dunlops on a fine grain limestone driveway around 200' long. Pick up lots of debris heading down the driveway with cold tires and coming back with warm tires nothing sticks. The exact opposite of what I'd expect.....

Lol. Well see. Im not completely nuts. I been meaning to get back to this thread. I was actually going to even make a video but Id hate for you guys to see how bored I get sometimes
I just experianced this again about 30 min ago when I got the guzzi out for a bar hop ride. Im leaning toward the what I clean the wheels with explanation for now (zep 40 aerosol glass clreaner).
I'll do a follow-up