1.25" slicks safe on a MTB?

[safe]

Shape is also very important.

You definitely want the "lip" of the tire because as you go into a lean the "lip" it the last part that holds traction. As the "lip" starts to lose it's grip it does so in a predictable manner. This is one of the reasons that knobby tires are so bad for the street because knobs tend to bend in a turn and the tires then let go without warning. The "lip" gives feedback to the rider and when it does let go it does so slowly.

The other day I was going UPHILL into a left hand turn that crossed over a hump in the middle. I was fully leaned over to the left and was going faster than usual on this stretch of road. The front tire started to slide as the hump unloaded the front end. Once gravity pulled me back down to earth the tire started to catch again and all was fine. The "lip" gave me enough feedback to know that I was in a front wheel slide, but it also recaptured traction without skipping a beat.

The other issue is steering geometry.

You can have a front tire that is simply "too square" and that will make for some bad handling. You want your rear to be a little flatter than your front. Ideally you want the rear to go into a controlled slide before the front starts to slide.

 

[michaelplogue]

From my experience, slick tires actually provide better traction on wet roads then tires with slight treading. Treaded tires 'trap' water during braking, whereas slick tires 'pushes' all of the surface water to the side. However, they are absolute crap for stopping on anything but clean roads - any bit of dirt or gravel and you can easily loose it. I would recommend compromising and getting a wide "City" treaded tire. These are significantly quieter and more efficient that full knobbies, yet still provide good grip on messy surfaces.

 

[Toshi]

For a given tyre cross-section, a larger diameter wheel will have a longer narrower contact patch than one of smaller diameter, but the area of the contact patch will be the same......

Air pressure in the tyre certainly increases under load.

So...... assuming a perfectly elastic tyre, and within reasonable limits, surely contact patch area in square inches equals weight of load in pounds, divided by no. of wheels, divided by PSI figure, no?

You and your grasp of physics are correct. 8)

 

[pizark]

cool, thanks for the help, everyone. I've decided to stick with slicks, but go to a 2+ inch tire.... as soon as I can get my ebike working. grrr....

I tried swapping a new throttle, new controller,... and nothing. I guess it's time to get a new motor?

grrrr...

 

[Mark_A_W]

If you a commuting any distance I would get Schwalbe Marathon Plus tyres.

I have 6000k on mine without a flat - through glass, rocks, dirt roads, bitumen, pedestrians, car bonnets, the lot.


They are worth the money. A flat on an Ebike is a PITA.

 

[monster]

Slicks are not good in the wet.

The usual sweeping overstatement...

I don't think aquaplaning is a problem affecting bicycles ....

dude you couldn't be more wrong! i used to run slicks and had all my weight in the rear carrier with only 2 front breaks. this was a serious problem in the wet because the front wheel would lock up when braking down hill. -REALLY SCARY-

i never came off but it was only a matter of time

 

[Miles]

Could you run that again Matthew? I couldn't follow your argument..

 

[safe]

Could you run that again Matthew? I couldn't follow your argument..

It's funny because I never bought into the aquaplaning argument, but then got accused of being on the side of it. :lol:

The conclusion was that wet pavement is slippery, but your choice of slick or tread will not matter in making it any less slippery.

Tread or not wet weather riding is always more slippery than dry.

Dry weather however definitely favors the slicks because there is more contact area.

You "notice" the difference more with the slicks because the dry weather performance is so good in comparision, but they actually aren't any worse in the wet than treaded designs.

This ends up one of those "double negative" situations where it's the opposite of the opposite that is true. (possibly why it's been confusing)

 

[kbarrett]

If your front wheel was locking up during braking in the rain with slicks on, then it will lock up even faster with knobbies.

Knobbies have less surface contact then slicks ... unless you are in loose crap. I used a 20" knobbie tire on the rear of my 'bent ...for a while. Sucker was a squirelly as all hell on wet roads ... could not turn sharply without breaking traction and beginning a fish-tail.

Double-plus-ungood.

Hydroplaning doesn't become possible until you exceed about 35 MPH ... at that point, tread patterns become useful for getting rid of water.

I have had the best commuting performance out of fat road tires with non-aggressive treads. I use a pair of Schwalbe Big Apples ... I might consider a set of Fat Franks later.

Treading, for me, is just for puncture protection.