How much faster is a road bike?

[Peka]

I'm currently on a cheapie Apollo MTB, and while I get along quick enough I know I'd be much quicker on a roadie. So, how much faster would I be on a roadie? My MTB weighs 16kg. I weigh 73 and already <10% body fat so I don't really need to loose any weight....

 

[Michael Warner]

On Wed, 7 Sep 2005 20:36:46 +1000, Peka wrote:

> I'm currently on a cheapie Apollo MTB, and while I get along quick
> enough I know I'd be much quicker on a roadie. So, how much faster
> would I be on a roadie? My MTB weighs 16kg. I weigh 73 and already <10%
> body fat so I don't really need to loose any weight....

On the flat, it doesn't depend on weight, but on the kind of tyres you have
on your MTB (the knobbly sort are really hard to push), and how much more
aerodynamic you are on the road bike, which depends mostly on how low
you set the bars relative to the saddle.

If you're currently using reasonably smooth tyres, expect an immediate
improvement of about 5 km/h, with more as you improve your postion
and technique on the roadie.

Up hills, it's all about weight - aerodynamics don't matter much. Since
you're already light and fit, it'd be worth your while investing in a
lighter, more expensive bike if you're interested in tackling them for the
reward of hooning down the other side

--
Home page: http://members.westnet.com.au/mvw

 

[GPLama]

"Michael Warner" wrote in message ...
> On Wed, 7 Sep 2005 20:36:46 +1000, Peka wrote:
>
>> I'm currently on a cheapie Apollo MTB, and while I get along quick
>> enough I know I'd be much quicker on a roadie. So, how much faster
>> would I be on a roadie? My MTB weighs 16kg. I weigh 73 and already <10%
>> body fat so I don't really need to loose any weight....
>

Everything Michael said is 2nded by me.. a great deal depends on the
terrain you ride on.. I have a boat anchor Apollo MTB which I can pull
almost the same averages on as my road bike... this is on a route that
includes mostly skinny not-so-smooth bike paths, I tend to back off on the
roadie given the loss of braking power..

Things I've done to quicken up my hardtail MTB:

- Flipped the stem for a more 'roadie' position.
- Installed a flat bar, and shaved a few cms of width off it.
- Road SPD-SL pedals, I'm going to MTB hell for this!
- Slicks.. though watch the weight on what slicks you choose, I find the 1.5
IRC Metros great for cornering but really sluggish for everything else.

MTB weight is the biggest downfall - and it costs big $ to get anything
under 10kgs in an MTB..

And looking at the other side of the coin, it isn't always about the tools..
if you haven't already invested some time into a good training regime, I'd
recommend getting some good books and reading up.. then setting some
goals... 16kgs of MTB is a good training!

cheers,
GPL

 

[Bleve]

Michael Warner wrote:
> On Wed, 7 Sep 2005 20:36:46 +1000, Peka wrote:
>
> > I'm currently on a cheapie Apollo MTB, and while I get along quick
> > enough I know I'd be much quicker on a roadie. So, how much faster
> > would I be on a roadie? My MTB weighs 16kg. I weigh 73 and already <10%
> > body fat so I don't really need to loose any weight....
>
> On the flat, it doesn't depend on weight, but on the kind of tyres you have
> on your MTB (the knobbly sort are really hard to push), and how much more
> aerodynamic you are on the road bike, which depends mostly on how low
> you set the bars relative to the saddle.

Just to be pedantic, weight does matter on the flat, although not
as significant as aerodynamic drag, it *does* increase rolling
resistance and also make acceleration slower, which "feels" slower
overall.


>
> If you're currently using reasonably smooth tyres, expect an immediate
> improvement of about 5 km/h, with more as you improve your postion
> and technique on the roadie.
>
> Up hills, it's all about weight - aerodynamics don't matter much. Since
> you're already light and fit, it'd be worth your while investing in a
> lighter, more expensive bike if you're interested in tackling them for the
> reward of hooning down the other side

It's also about gearing. Very few MTBs have the gears to go
fast.

 

[hippy]

It's also about gearing. Very few MTBs have the gears to go fast.

85kph down the Konigstuhl yesterday (75kph just rolling!). Could've done with bigger gears. The hairpins don't help max speed either

slow hippy

 

[SomeGuy]

MTB weight is the biggest downfall - and it costs big $ to get anything under 10kgs in an MTB..

Does it? I've turned my Giant Rincon into a road (in the sense that I'm going to ride it on paved surfaces) bike, and once finished it should weigh 9.9kg . Total weight loss over 6kg. As for what I did:

2.2kg Suntour XCP-80 replaced by 0.7kg Kinesis rigid alu. Cost $200.

Thick tires, tubes, and wheelset replaced. For a wheelset I went with Bontrager Racelite UST (1.35kg) which was left over from my XC mtb upgrade to disc. The wheelset originally cost me $250 with an XT cassette and two tires. With the tires I decided not to go too weight weenie, and picked Maxxis Xenith 1.5 with a folding bead. A shade under 400 grams each. Inside are 100 gram lightweight tubes. Tires + tubes $120.

0.3kg stock stem replaced by longer stem with less rise (0.2kg). Not really a weight thing, but it improved my position a heap. Cost $10.

I also replaced the cranks ($120) cassette ($30) and chain ($40), for wear rather than weight reasons - although the new kit is lighter . For longer rides I lose a few hundred more grams by taking the entire saddle+seatpost from my XC race bike and putting it in. Down the track I'm hoping to upgrade my XC bike with a carbon bar and hand it's light flat bar down. 105 derallieurs and 11x27 cassette would also on the wish list.

Sorry about that, I'm very good at getting longwinded. What I was trying to say is you can lose a lot of weight weigh spending *too* much by targeting the right parts and keeping an eye out for bargains.

 

[Bleve]

hippy wrote:
> Bleve Wrote:
> >
> > It's also about gearing. Very few MTBs have the gears to go fast.
>
> 85kph down the Konigstuhl yesterday (75kph just rolling!). Could've
> done with bigger gears. The hairpins don't help max speed either

heh, how much ballast on the bike, and what cadence?

 

[Kathy]

Peka wrote:
> I'm currently on a cheapie Apollo MTB, and while I get along quick
> enough I know I'd be much quicker on a roadie. So, how much faster
> would I be on a roadie? My MTB weighs 16kg. I weigh 73 and already <10%
> body fat so I don't really need to loose any weight....
>
>
As some may know, I recently converted from a Mongoose hybrid to a new
OCR 0... My top speed on the hybrid was 29k - with extreme(!) effort -
for a short while - average was about 15kph. The OCR averages about 23k
- quite easily as far as pushing the bike along goes - and top is about
the same as the old bike, but rolling easily around the velo rather than
pushing it totally along the road... Not definitive, but geez am I glad
I made the change!

 

[Peter Signorini]

"Peka" wrote:
>
> I'm currently on a cheapie Apollo MTB, and while I get along quick
> enough I know I'd be much quicker on a roadie. So, how much faster
> would I be on a roadie? My MTB weighs 16kg. I weigh 73 and already <10%
> body fat so I don't really need to loose any weight....

You really need to think about what you are intending to use this MTB/road
bike for. When it comes to recreational riding and commuting the lightness
and acceleration of a light roadie sure is nice, but not essential to have a
good ride. Much more important that the bike suits the intended use and is
comfortable for you. Speed in a a road bike is mainly used for making sudden
jumps up hills and te final sprint to the finish. Over the total length of a
ride of, say 80kms there will be surprisingly little difference between
someone riding a road bike and someone on a *suitably equipped* MTB. A far
more significant factor is the rider's level of fitness.

By suitably equipped I would suggest a MTB with fairly low-set straight
bars, with bar-ends; using a wide range of gears, but still some good high
gears (44-11 top); fitted with light wheels and high pressure slicks (IRC
Metro Duro 1.5" tyres can run at up to 100psi, good and fast); and fitted
with a good, comfortable saddle - not a couch!

After I bought my MTB, that I now use for touring of all types, I had it
setup like this. Many friends commented that it would be slower, but the
reality on rides is that it wasn't. I paced the same speed as the rest.
Once, in a roll test down a steep 3 km hill with a friend on a road bike, I
rolled to 73kmh, he rolled to 76kmh. This amounted to about 10 metres
difference at the bottom. The difference between a win and 6th in a race,
but for regular riding pretty immaterial.

As for weight, my steel MTB pegs in at 19kg (!!) with all its accessories.
Pretty damn heavy, I know, but I have never felt this weight to be a problem
when riding with friends. A more crucial factor is how fit I am, not the
greatest at present due to lack of ride time. When I am fit I always find
that I can leave most people behind on hill climbs and pace it with the best
on the flat. you develop a level of fitness to suit the bike you ride. But
my riding is in a touring club group, not a road race bunch or
pseudo-racers.

So look at what sort of riding you do. If you intend to get into racing,
traithlons or Audax riding, shop around and get a road bike, but make sure
it fits you well. If you are more into recreational touring, bike path
riding or commuting, then either a road bike or a road-equipped MTB will
suit you well. My preference is back-track touring and for this the MTB wins
hands down.

Cheers
Peter

 

[ritcho]

[snip]

So look at what sort of riding you do. If you intend to get into racing,
traithlons or Audax riding, shop around and get a road bike, but make sure
it fits you well.

[snip]

Cheers
Peter

This bit deserves to be singled out and repeated (I totally agree with the rest by the way). It doesn't matter if you have a UCI weight limit buster if it sends you to the chiro after fifteen minutes...

My answer to the OP is somewhere around 2-5km/h faster... As P indicated, that doesn't necessarily equate to "better" for your intended purpose.

Ritch

 

[Peka]

So many replies so quickly

You really need to think about what you are intending to use this MTB/road bike for

OK, some more info - it has bar-ends & 1.25 road tyres at 100psi. Top gear is a 42-11. I commute 3 days a week, and try and get a longer ride on the weekend, which is either in the dirt or as I've just started doing, up a climb (such as Mt Cootha). I've also started going through Griffith Uni and up the ******* hill next to ANZ stadium on the commute, because I know those hills will do wonders for my fitness.

So, it suits my needs well at the moment. I'm keen to get a roadie at some stage as I like going down mountains, which means I have to go up them first

 

[Dancier]

When I started to ride mountain bike some 15-20 years ago, I was told the effeciency difference was about 25%. I think it's probably closer to 40%.

40k per hour is about the limit for my MTB, my road bike does the same speed in the middle chainring with less effort.

I was riding up beach road into the wind a few months ago with a friend. I was on the MTB and he was on his road bike. I was going flat chat and he was on holidays, putting in half the effort.

 

[Michael Warner]

On Thu, 8 Sep 2005 09:40:52 +1000, Peka wrote:

> So, it suits my needs well at the moment. I'm keen to get a roadie at
> some stage as I like going down mountains, which means I have to go up
> them first

I thought tractor riders solved that problem by getting someone with a ute
to drive them and their bike up the mountain

--
Home page: http://members.westnet.com.au/mvw

 

[hippy]

hippy wrote:
> Bleve Wrote:
> >
> > It's also about gearing. Very few MTBs have the gears to go fast.[/color]
>
> 85kph down the Konigstuhl yesterday (75kph just rolling!). Could've
> done with bigger gears. The hairpins don't help max speed either [/color]

heh, how much ballast on the bike, and what cadence?

hehe Actually, at last check my weight was less than when I left Oz. I just think I'm carrying more fat and less muscle now. Given the fact I'm doing no training and eating too much German food, that makes sense.

Cadence unknown - no sensor and I was thinking more about the skidding around corners than counting pedal strokes.
This could work it out: http://www.analyticcycling.com/

I have DeoreLX groupset - looking at the specs, it's either 44-11 or 48-11. I'm guessing the former.

I don't know the wheel diameter, so I left 0.674 in and it calculated cadence of 167rpm for a speed of 85kph.

hippy

 

[Peka]

I thought tractor riders solved that problem by getting someone with a ute to drive them and their bike up the mountain

Pffft, bunch of weekend warriors "What! You rode 15km to get to the state forest to go MTB riding?!??!