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-   -   I got left in the dust. MTB on the road. (http://www.bikeforums.net/general-cycling-discussion/579782-i-got-left-dust-mtb-road.html)

mr,grumpy 08-30-09 10:53 AM

I got left in the dust. MTB on the road.
 
Lessons learned today! I was pretty excited that I got my old Ross Bryce Canyon mountain bike all tuned up and adjusted. I took it out on my 6 mile loop and got DUSTED by some guy on his Cannondale road-somethingorother with aero bars. I was trying to keep my cadence up since I'm a fat guy and he was definitely not peddling as fast as I was but he was just so.....smooth. So what did I learn? That riding a mountain bike with 2.1 inch full-on knobbies on the road is HARD! And that I'm still not very fit.

JohnDThompson 08-30-09 12:51 PM

Quote:

Originally Posted by mr,grumpy (Post 9583240)
So what did I learn? That riding a mountain bike with 2.1 inch full-on knobbies on the road is HARD!

Yup. If you're planning on riding on the road most of the time you'll probably want to replace those 2.1" knobbies with something narrower with a slick tread. Not only will they wear longer, but they're much easier to push down the road.

Cipher 08-30-09 12:54 PM

Persevere dude, fitness wil come! :thumb:

runner pat 08-30-09 01:14 PM

What doesn't kill you makes you stronger.




Or hurts real bad.

mr,grumpy 08-30-09 07:48 PM

I wish that that had happened while I was riding the Peugeot. It would have been a better measure of how I stacked up to a more experienced cyclist than trying to push a couple of pounds of fat, floppy rubber down the street. On a positive note, I never used the small chain ring for anything, all ride. One thing that confused me about the other cyclist. He was a nice enough fellow. Said hello and warned me that he was passing. I swear he said "On the right!" as he was passing me on the left. It was probably just the blood pounding in my ears.

RatedZeroHero 08-30-09 07:56 PM

Quote:

Originally Posted by JohnDThompson (Post 9583680)
Yup. If you're planning on riding on the road most of the time you'll probably want to replace those 2.1" knobbies with something narrower with a slick tread. Not only will they wear longer, but they're much easier to push down the road.

replace those 2.1s with a Trek 2.1 you'll be beating him... (or is it a 2.3 either way...)

arej00dazed 08-31-09 04:56 AM

would a tire with a "slick center" and outter knobbies still slow you down?

Lord Chaos 08-31-09 05:31 AM

Think of it this way... when you come to the end of pavement, you may have gottten there slower but you can keep on going. :)

BlazingPedals 08-31-09 06:12 AM

A mountain bike will be slower on the road than a road bike, no matter what. You can decrease the difference in performance by running narrow slicks instead of fat knobbies, but the geometry weight and gearing will still be working against you.

Re: tires - Think of it this way. Rubber deforms when put under pressure, like at the contact point with the road. Tread and knobs allow the rubber to squirm more than a solid layer of rubber. Deformation requires energy, which comes from your pedals. So, the more rubber/tread you have, the more rolling resistance you will have. Plus, skinnier tires will have less air resistance. So the fastest tires will be skinny slicks with very little rubber. That pretty much describes roadie racing tires.

You can get slicks in 26x1, if your rims aren't too wide. Even 26x1.25 slicks would be relatively fast compared to your knobbies.

mr,grumpy 08-31-09 06:41 AM

Quote:

Originally Posted by arej00dazed (Post 9587010)
would a tire with a "slick center" and outter knobbies still slow you down?

Yep. I have tires like these on my "regular" bike and they are not as wide overall and have the knobs meld into each other in the center of the tire. In fact, I never rode a full-on knobbie bicycle tire on the street before. I'm not anxious to do it again either. They have to come off sice I have no intention of using this bike as a n off road tool. There is very, very little stand-over height on it for me. This bike is heading to the country house to be used on the paved and dirt roads up there. I'll wind up getting some semi-aggressive street type tires for it.

meanwhile 09-01-09 04:50 PM

Quote:

Originally Posted by arej00dazed (Post 9587010)
would a tire with a "slick center" and outter knobbies still slow you down?

No. It send you into corners at a nice high speed so that the corner knobbies bend throwing you into an outwards skid. You can do this with true off road tyres too with some effort.

cachehiker 09-01-09 05:00 PM

Quote:

Originally Posted by BlazingPedals (Post 9587162)
A mountain bike will be slower on the road than a road bike, no matter what.

Not necessarily. My Zaskar is my travel bike. On road, off road, in between, I'm just a wheel swap away when my buddies are bringing two bikes. At 22 lbs. with the race wheels and 1.6" slicks, it's close to the same weight as and entry level road bike and I routinely outride roadies on it.

meanwhile 09-01-09 05:10 PM

Quote:

Originally Posted by BlazingPedals (Post 9587162)
A mountain bike will be slower on the road than a road bike, no matter what. You can decrease the difference in performance by running narrow slicks instead of fat knobbies, but the geometry weight and gearing will still be working against you.

This is nonsense...

1. Frame geometry has no real effect on speed - it determines turning characteristics and stability. (Yes, aerodynamics matter - but they are more a result of stem and bars.)

2. Bike weight also has little effect indeed on speed. It matters most on a climb, but even here it's the total weight of the rider and bike that matter and bike weight reductions have to be scaled by this total sum. On the flat, bike weight is even less of a limit to speed.

3. This may come as a shock, but the chainrings and cassette on your bike are not permanent fixtures. Your LBS should have no problem fitting your MTB with gearing that would max out LA's ability to maintain a steady pace on the road - OK?

A non-suspension mountain bike's real problem in keeping up with a road bike - once suitable tyres have been fitted - is 99% down to the aerodynamics of rider position. I almost bought a Stumpjumper that had been fitted out as a winter trainer by a roadie - a single speed with very aggressive TT bullhorns. On flat ground it was faster than his Allez. If the Allez had been fitted with aero bars then I'm sure it would have re-taken the advantage.

Quote:

Plus, skinnier tires will have less air resistance. So the fastest tires will be skinny slicks with very little rubber. That pretty much describes roadie racing tires.

You can get slicks in 26x1, if your rims aren't too wide. Even 26x1.25 slicks would be relatively fast compared to your knobbies.
You have to be moving very fast indeed for tyre frontal surface area to matter. Tyre aerodynamics were literally the least of the OP's problems...

Panthers007 09-01-09 05:57 PM

I was left way back by a guy riding a well-maintained Klein. But he was wearing a 'bug-suit' - I said "Nice bike!" to Mr. Bug as he passed me. He just looked at me through his $250 sunglasses and didn't acknowledge my greeting. I felt like a yellow-jacket had sneered at me.

Spider 09-02-09 10:51 PM

Quote:

Originally Posted by meanwhile (Post 9596913)
A non-suspension mountain bike's real problem in keeping up with a road bike - once suitable tyres have been fitted - is 99% down to the aerodynamics of rider position.

Wheel size is also a factor, as explained here. Their tests concluded that 700c wheels were more stable at high speed and faster overall than 26" wheels.

meanwhile 09-03-09 05:25 AM

Quote:

Originally Posted by Spider (Post 9605218)
Wheel size is also a factor, as explained here. Their tests concluded that 700c wheels were more stable at high speed and faster overall than 26" wheels.

Bollocks.

These "test" assumed a bike was faster if just felt faster to some muppet riding it. As Keith Bontrager noted, properly controlled experiments show that the opposite is often the case. To describe this source as describing "tests" and having "conclusions" is extremely generous.

And even the source admits that their "results" applied only to tandems. More, given the testing was only with their own brand of tandem (afaik - the chosen colours make the source very hard to read) all one can really conclude, at most, is that this company designs better 700c tandems than 26'' - in the opinion of a small group of riders.

To be fair to the source it admits that there are many examples of high speed bikes with 26'', 20'', and even 17'' wheels and that its tests don't negate this - you really should have read more carefully.

Also this is just wrong:

Quote:

Why is wider slower? To apply the extra width against the pavement, the tread and sidewall of the smaller yet equally-wide tire is forced to undergo a great deal of additional contortion --- and tread and sidewall squirm are the primary causes of rolling resistance
- in fact wider at the same pressure with the same tyre compound is lower RR; see eg the tech docs on Schwalbe's site or http://www.sheldonbrown.com/brandt/r...esistance.html

Spider 09-03-09 08:02 AM

Quote:

Originally Posted by meanwhile (Post 9605875)
As Keith Bontrager noted, properly controlled experiments show that the opposite is often the case.

Link?

Quote:

Originally Posted by meanwhile (Post 9605875)
you really should have read more carefully.

:rolleyes: No reason to be snide about it.

meanwhile 09-03-09 09:28 AM

Quote:

Originally Posted by Spider (Post 9606563)
Link?

You'll have to use the Wayback Machine - Bontrager's most interesting articles got taken off the web after his company was acquired by Trek. It's easy to see why if you read them.

There was an even better paper by two brothers who had a custom frame business, possibly written for an engineering masters. They were looking for optimum trail angle and chain stay length, and one of the things they found was that even experienced riders had no ability at all to say which bikes (within a test group of conventional designs) were accelerating faster or turning tighter by feel. I had a copy and now I can't find the damn thing!

My Sirrus "felt" faster than my cross bike - but times show the cross bike to much be faster. I think the reason was that the Sirrus buzzed like hell and didn't handle as well, so lower parts of my brain sent "Whoa! This is too fast !" signals that coloured my perceptions.

The cross bike (a limited production boutique bike by a UK bike store) otoh, handles so well that I have been shocked at how fast I was moving when I rounded a turn and came to a Known Reason To Brake. Like the anti-quad bike railing across the trail that I nearly went through like a human egg slicer...

Quote:

:rolleyes: No reason to be snide about it.
Sir - if you present an opinion poll as if it is science, I shall be snide, testy and snippy. This was a ludicrously poor source and you read it badly.

Retro Grouch 09-03-09 09:48 AM

Quote:

Originally Posted by mr,grumpy (Post 9583240)
Lessons learned today! I was pretty excited that I got my old Ross Bryce Canyon mountain bike all tuned up and adjusted. I took it out on my 6 mile loop and got DUSTED by some guy on his Cannondale road-somethingorother with aero bars. I was trying to keep my cadence up since I'm a fat guy and he was definitely not peddling as fast as I was but he was just so.....smooth. So what did I learn? That riding a mountain bike with 2.1 inch full-on knobbies on the road is HARD! And that I'm still not very fit.

"When you're up to your ass in alligators it's hard to remember the objective was to drain the swamp."

It's so easy to get side tracked. When you started your ride I'm pretty sure your objective wasn't to beat the fellow on the road bike because you didn't know he would be out there. So what was your reason for taking the ride? Fun? Gaining fitness? Whatever it was, did you accomplish that? If so you should be celebrating rather than looking for a cloud to hide the sun.

Laggard 09-03-09 09:56 AM

Keep in mind that Tom Boonen could drop all our sorry asses if he was riding a childrens bmx bike purchased at Walmart.

Spider 09-03-09 10:24 AM

Quote:

Originally Posted by meanwhile (Post 9607157)
You'll have to use the Wayback Machine - Bontrager's most interesting articles got taken off the web after his company was acquired by Trek. It's easy to see why if you read them.

Too bad. Would like to have seen that.

Quote:

Originally Posted by meanwhile (Post 9607157)
My Sirrus "felt" faster than my cross bike - but times show the cross bike to much be faster. I think the reason was that the Sirrus buzzed like hell and didn't handle as well, so lower parts of my brain sent "Whoa! This is too fast !" signals that coloured my perceptions.

The cross bike (a limited production boutique bike by a UK bike store) otoh, handles so well that I have been shocked at how fast I was moving when I rounded a turn and came to a Known Reason To Brake. Like the anti-quad bike railing across the trail that I nearly went through like a human egg slicer...

I've experienced the same miscalculation of speed in cars. As an old beater rattles and shakes and makes lots of engine noise, it seems like it's going faster than it really is. Whereas when driving a finely tuned, well engineered, quality car, I find myself traveling at excessive speeds without realizing it.

Quote:

Originally Posted by meanwhile (Post 9607157)
Sir - if you present an opinion poll as if it is science, I shall be snide, testy and snippy. This was a ludicrously poor source and you read it badly.

Suit yourself. Having read some of your posts, I can see that you make excellent arguments, but your delivery is often less than civil. Too bad. You'd win over a lot more people with a more respectful approach. Admittedly, that's just my (non-scientific) opinion.

mr,grumpy 09-03-09 09:13 PM

Quote:

Originally Posted by Retro Grouch (Post 9607304)
"When you're up to your ass in alligators it's hard to remember the objective was to drain the swamp."

It's so easy to get side tracked. When you started your ride I'm pretty sure your objective wasn't to beat the fellow on the road bike because you didn't know he would be out there. So what was your reason for taking the ride? Fun? Gaining fitness? Whatever it was, did you accomplish that? If so you should be celebrating rather than looking for a cloud to hide the sun.

YES!! I had two goals that morning:
  • to ensure that the I had properly tuned the bike and
  • get out for some fresh air and exercise
I achieved BOTH of those goals and was quite pleased with the results. I now have a very nice country bike that I dropped off at the country house today and I did not get ANY fatter last week. I also renewed my appreciation for my too old and too small Peugeot that is STILL way faster on the street than any of my mountain bikes are, and saw a wonderful example of how smooth and effortless cycling can look when done by some one with the right commitment to equipment, training and fitness. Not some guy on a fancy international cycle team riding a fram made from unobtanium, but a regular guy on a regular bike on a regular road. Far from being a cloud around my silver lining he was a reality check that I am still not that fit and a great example as the what can become of me if I "put in my time".

meanwhile 09-04-09 06:50 AM

Quote:

Originally Posted by Spider (Post 9607524)
Quote:

You'll have to use the Wayback Machine - Bontrager's most interesting articles got taken off the web after his company was acquired by Trek. It's easy to see why if you read them.
Too bad. Would like to have seen that.

What's hard about using the Wayback machine? You type its name into google, click on the link... Ok, then searching gets messy. But the article is here:

http://web.archive.org/web/200010222...1_01_1998.html

- an excellent discussion of frame flex, since born out by finite element analysis.

The other "rants" that disappeared are here:

http://web.archive.org/web/200008190.../rants_f1.html

Wish I could find the trail angle paper!

Quote:

I've experienced the same miscalculation of speed in cars. As an old beater rattles and shakes and makes lots of engine noise, it seems like it's going faster than it really is. Whereas when driving a finely tuned, well engineered, quality car, I find myself traveling at excessive speeds without realizing it.
Sure.

Quote:

Suit yourself. Having read some of your posts, I can see that you make excellent arguments, but your delivery is often less than civil.
Definitely true.

Quote:

Too bad. You'd win over a lot more people with a more respectful approach. Admittedly, that's just my (non-scientific) opinion.
You assume that I want to win you over. What I actually want to do is to make you think before mis-reading sources or claiming credibility for a source that is clearly junk. Frankly, if I could then I'd slap you around the head with a medium sized rotting fish and disqualify you from voting until you got this right. And if the fish didn't work, then in an ideal world you'd be neutered, to stop your Poor Source genes being passed on. It's this sort of cognitive malfunction that causes global warming and most wars. Stop it already!

(Excellent empirical evidence suggests that negative stimuli work better than positive ones here.)

Spider 09-04-09 09:01 AM

Quote:

Originally Posted by meanwhile (Post 9612794)
You assume that I want to win you over.

I don't assume that you want to win me, or anyone else here, over. I assume you enjoy belittling people. What I am saying is that you have valuable information to impart, and if it were delivered in a more respectful manner, people would be more accepting of it, and your presence in this forum would be more beneficial.

Quote:

Originally Posted by meanwhile (Post 9612794)
What I actually want to do is to make you think before mis-reading sources or claiming credibility for a source that is clearly junk. Frankly, if I could then I'd slap you around the head with a medium sized rotting fish and disqualify you from voting until you got this right. And if the fish didn't work, then in an ideal world you'd be neutered, to stop your Poor Source genes being passed on. It's this sort of cognitive malfunction that causes global warming and most wars. Stop it already!

I read the source just fine. I reported what the writer concluded. It was the only article I could find on speed difference (if any) between 700c and 26" wheels, and it was written by the president of a bicycle company. You don't like the source? Fine. Show me the peer-reviewed, scientific article on the subject, and I will be happy to read it.

iforgotmename 09-04-09 03:25 PM

Quote:

Originally Posted by Retro Grouch (Post 9607304)
"When you're up to your ass in alligators it's hard to remember the objective was to drain the swamp."

It's so easy to get side tracked. When you started your ride I'm pretty sure your objective wasn't to beat the fellow on the road bike because you didn't know he would be out there. So what was your reason for taking the ride? Fun? Gaining fitness? Whatever it was, did you accomplish that? If so you should be celebrating rather than looking for a cloud to hide the sun.

Well said :thumb: +1


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