MTB slicks thread...

artemidorus

Don't start creating roadie conspiracy theories and leave the ham theatrics out of it. I commute both on an MTB and a roadbike and have no particular bias.
Let me make it simple for you:
You tell us that 2+" MTB tyres allow a very low rolling resistance. This is counterintuitive, and something that noone else espouses, and so we aren't going to buy it without proof. Proof comes from data. Very simple. If you don't like laboratory data (although such a dislike is irrational), then look for studies with power taps on real bikes in the real world. If they don't exist, then we will simply accept that what you are saying is opinion only. That's cool, but it would be polite of you to make it clear from the beginning that it is opinion.
Momentum of the whole system, by the way, is much more significant than the rotational momentum of your tyres. If you weigh much less than my 90kg, then you are not going to come rolling past me on the flat, regardless of your tyres.

jur

Yep. We want proof. If you can't supply that, then pipe down already.

ps to improve your posts, make them short and concise. AND tentative.

jur

Been there, done that. Flat bar road bike. e.g. Giant CRX series. Why would you blow your bucks buying a roadie and convert that down???? Much cheaper to get a flatbar racer.

jur

Here is some real data. Let's see danielhaden's.

danielhaden

I've just got to know: Fast 1.75 tires??
I've never had luck with that size.
Are they available in a 26" version?
Is a "file tread" or modest tread version available for city riders?

Thank you!

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Bar end shifters, new internal gear hubs, and "new" performance tires with tread--proof that at least 3 sane people exist.

danielhaden

Why would you do this?

If you start with a machine designed for speed. . .
Equip it with a speedometer. . .
Make only one change at a time. . .

Then you can add features to it while easily measuring any effect on speed.

This is certain, except for, and in my opinion, changes that make you feel better may encourage you to go much faster while better health may enhance longer rides.
And, also in my opinion, that is not an invalid way to go faster.

In my experience (yours may differ, and I hope it does), if you do not start with a machine designed for speed, then you have to deal with all of the variables at once with no established point of reference.

__________________
Bar end shifters, new internal gear hubs, and "new" performance tires with tread--proof that at least 3 sane people exist.

danielhaden

Okay! But, I'll ask for your help on something at the end. . .

My study of large tires was only for those who are addicted to the sensation of large tires. In my opinion, these cannot compete for a gold medal, but few can add much speed to a mountain bike without loss of this sensation. I believe that people who disagree are uninterested in this aspect.


As for my other study. . .

I have been unable to compare my results with the chart data because, even at the same size (especially at the same tire size), the effects and application of hard vs soft tires is completely different, even though timings and speedometer show similar or enhanced speeds. I have some results.

What is tested:
Durable, yet flexible, road tires that I tested have hit-or-miss performance in comparison to race tires. The greatest success has been the smallest size Pasela TG, T-Serv and Ruffy Tuffy--only successful when applied to narrow rims. Since my concentration is in adding features without losing features or speed, and not competitive sport, the limited data I have to report to you at this time is:

Fourty-two pleased weekend warriers who report same or faster speeds via timing or speedometer.
This is not especially valid data because of:
1) The variety of tires replaced--varies.
2) The comfortable cyclist seems to perform much differently.
3) The bikes are used on rough pavement where touring tires excel.
4) Frequently, only the front tire was replaced.
5) Confidence may encourage non-athletes to cycle faster.
6) The point of the work is health benefit rather than performance increase, so sizing is often adjusted at the same time as a tire change, and this was performed by different people.

For competitive sport, the only use of this study (I believe) could be the enhanced performance on tarmac, cobblestone, rough pavement, packed gravel, nails, screws, glass, wire, shards, wet manhole lids (tested w. T-serv), squirrels, fallen branches, motor oil, bricks, bones, fruit, sand, loose patches, lost car parts, and a variety of wet surfaces with an amount of water (or water and oil) that also varies.
This is not on performance charts for race tires. Comparison is beyond my ability, but thanks for asking.

The link was useful to me because:
To me, it highlights that a larger contact patch gives much more room for error in the area of rubber formula friction/grip vs. size of contact patch. That's why I think that very narrow rims are a more-certain way to get performance.
To me, safe bets are as entertaining as the job of vacuuming the floor, except when something goes awry, such as my project of increasing a Hoover that was a great success on carpet but would suddenly destoy a throw rug or put dirt onto a hard surface. In this same way, large roller tires and small race tires alike can have very unpredictable results on non-optimal surfaces.

I have attempted to ignore the combination of gravel with 1.5 to 1.75 mountain bike slicks even though it is unusually speedy, because I have had no luck with these on pavement when their job is be competing with a road tire. My favorite road tire was remarkably slow when increased to this size in the exact same rubber compound. In my test, those that came close to high performance were remarkably prone to slide, while there were both smaller and larger options (with similar to higher performance) that do not slide (showing that sliding can be unnecessary to performance).

Help!

Can somebody shed some light on this (available mid size mtb slick, fast, does not slide)?

__________________
Bar end shifters, new internal gear hubs, and "new" performance tires with tread--proof that at least 3 sane people exist.

gclark8

Daniel,

Hello!

This is an Australian Forum and a local topic!!

We try to discuss what is available here, locally and what suits our climate and riding styles.

So, take your Hypothetical Yankee Crap and go home!!

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Cheers,
George.

jur

But haven't you found your ideal tyre in the Schwalbe Big Apple? The Super Moto could be better even. According to Schwalbe, they have very low rolling resistance due to casing design, give nice suspension due to the balloon effect and have a good grip due to the large contact patch.

danielhaden

Bravo!

I haven't tested them yet.

I purchase tires for a particular application--that's when I sometimes get to test them. It is the reports of "better traction than the Big Apple" that cause me not to purchase these because. . .because of the ever increasing pile of slow tires that have all advertised improved traction next to the bigger pile of slow road tires that have offered "the same thing" in a larger size.
I fear the rubber compound may be more sticky. Curiosity about these will catch me eventually! And then I'll get some. The "Fat Frank" from Schwable is once again up in the bombproof class, but this time with a rolling block pattern that keeps more of it up off the road. Now, that's interesting. That, and some helium. It is so very tempting to try that.

__________________
Bar end shifters, new internal gear hubs, and "new" performance tires with tread--proof that at least 3 sane people exist.

jur

heh heh, we Aussies are a sceptical bunch. And you are ruthless

danielhaden

My apologies! With your attitude, I had assumed that you were from the United States.

__________________
Bar end shifters, new internal gear hubs, and "new" performance tires with tread--proof that at least 3 sane people exist.

skyther

Hey, hope I'm not O/T-ing but what sorta pressures are you guys running on your SportContacts? Any recommendations as to what I should use on my 1.6"? I'm not really concerned about bumps, I just like things fast. Not really sure what's the maximum that my tyre and tube can handle though...

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'05 Yukon LX/XT, X221/DT/SportContact 26x1.6

gclark8

Sport Contact 1.6.
From the 2006 Conti book:
Recomemded: 65psi
Max: 80psi
However it should be safe to go 10% over max.

__________________
Cheers,
George.