How much energy is wasted with MTB tyres & suspension?

rubadub

How much energy is wasted with MTB tyres & front suspension? I was thinking of getting a MTB for messing around on, I also feel it is safer in the wet and the coming icy mornings.

Just wondering if there are any webpages showing how much energy is lost to suspension and thicker tyres?
If my journey took 30mins on a racer how long would it take on a MTB at the same energy usage per min?

I do not mind wasted energy too much since I cycle partially to keep my weight down. Just wondering how much effect it did have.

milod

rubadub wrote:

I also feel it is safer in the wet and the coming icy mornings.

Let's see now - knobbly tyres and wet/icy roads... as long as you get off bike and wheel it around corners you should be fine - there's some energy wasted already!

Seriously though, stick to a road bike with treaded tyres for the winter and take the long way to work if you want to keep the weight down.

rubadub

On my commute I am stopping a lot and lifting my bike over broken glass, slowing down for all of the kerbs on the cyclelanes etc. When I add up the time of this I may actually be faster on a MTB where I dont have to worry about such things.

Cabaal

switched from MTB to Hybrid recently and I have to say the lighter bike and lack of suspension makes a massive different, alot faster then the MTB.

Frankly I'd stay with the roadbike, perhaps change the tyres and/or go a longer route

blorg

The only way you are going to know is to try test riding one. Personally I would find it very frustrating moving from a road to a mountain bike for on-road riding; the roads simply aren't that bad and I would be feeling the slowness.

If you currently have a road bike, you could also just try thicker tyres? I have 700x28 on my tourer. Also good Kevlar tyres and you shouldn't have to worry so much about the broken glass and so on.

I also recently got a mirror which is proving _very_ useful as it allows me to cycle in the bus lane where the cycle lane degenerates to the point of unusability. What's your commute?

Johnny Jukebox

You can get full suspension MTBs which act as hardtails on descents and the flat, but its expensive. I run a combination of the Fox/Specialized Brain shock on the rear and Fox Terralogic 80 fork on the front, and, properly tuned, it runs as a hardtail kicking into full sus when I hit a big enough bump. It works just fine.

Remember also, MTB wheels are smaller than a roadbike.

Knobbly tyres are a huge drag, if you commute on an MTB change to slicks.

And yes, you'll spend a lot of time avoiding obstacles on a roadbike that you'd cruise over on an MTB.

rubadub

Thanks for the tips. I was really looking to find a technical website with acutal calculations about this, just me being a bit nerdy.

I have a hybrid at the moment. I hate having to take it easy, and avoid all the glass etc. I have had 4 punctures in the last 2 months. My journey is about 10miles. Am on the bike around 40mins per day, so my commute in the last 2 months/8 weeks is say, 8weeksx5daysx40mins= 1600mins. Those 4 punctures add an average of 60 additional minutes each, so that is 240mins extra over 40days, or 6mins per day.

They were puncture resistant tyres, but yes I should carry a pump and spare tubes too, I do sometimes but had none these days. I would not have gotten a puncture with what I ran over if I had a MTB. I am noticing lots of people with punctures on my way to work these days.

Punctures aside I want the other bike for safety reasons on the ice and wet, I also use the bike at weekends for exercise and find a MTB more comfortable to cycle, and I can go off road, or on dodgy roads too. This will be a second bike, not a replacement. A lot of the time my punctures are not seen until the morning when I go to take my bike out, even with a tube in the house I will be a little late for work changing it. Nice to have a standby

8kvscdpglqnyr4

This site doesn't show exactly what you are looking for, but it gives all the equations you need to figure it out for yourself:
http://damonrinard.com/aero/formulas.htm

You'll need to make a guess at the "coefficient of rolling resistance" for a MTB Vs a road bike if you want to do the calculations.

If you look at Figure 3, the author compares various styles of bikes and for a "Dutch Style upright" bike he more than doubles the "coefficient of rolling resistance" compared with a road bike.

In case you are wondering what a "Gold Rush" is ... it's a recumbent bike. I think it's fascinating to compare power required by the rider to push a recumbent bike at a particular velocity compared to a "normal" road bike.

rubadub

Kieran Witty Mouthwash wrote:

This site doesn't show exactly what you are looking for, but it gives all the equations you need to figure it out for yourself:
http://damonrinard.com/aero/formulas.htm

You'll need to make a guess at the "coefficient of rolling resistance" for a MTB Vs a road bike if you want to do the calculations.

If you look at Figure 3, the author compares various styles of bikes and for a "Dutch Style upright" bike he more than doubles the "coefficient of rolling resistance" compared with a road bike.

In case you are wondering what a "Gold Rush" is ... it's a recumbent bike. I think it's fascinating to compare power required by the rider to push a recumbent bike at a particular velocity compared to a "normal" road bike.

Cheers, gave me a few phrases to google.
Found this
http://www.kreuzotter.de/english/espeed.htm

Bunnyhopper

I use an MTB on- and off-road, but I don't commute so having a bike just for the occasional on-road run doesn't make sense. I actually quite like using the MTB on the road because it means I have to worry a great deal less about potholes, kerbs, drain covers and all the other nonsense you encounter on Irish roads.

One thing that makes a massive difference is tyre pressure. Some people like to run tyres a little soft off-road, but on the road pumping them up good and hard makes a huge difference to your efficiency. Even with knobbly tyres on an MTB you can really feel the difference. (In fact, you can hear the difference.)

PS And if the snow and ice get really bad you can invest in a set of these
http://www.peterwhitecycles.com/studdedtires.asp
lol

rubadub

Bunnyhopper wrote:

PS And if the snow and ice get really bad you can invest in a set of these
http://www.peterwhitecycles.com/studdedtires.asp
lol

Yes the tyre pressure makes a huge difference, my speed improved dramatically before when I pumped up the tyres on one I had a loan of, the guy had them very low for off road use.

Just cycle around irish roads for 10mins and your tyres will have plenty of studs and glass in them to grip the ice

kona

i hate when people ask this stoopid question.
a proper racer takes upto 100psi a mtb tyre takes 45psi max, this makes the road bike quicker for the simple reason that
the increse in pressure reduces the area for friction to act on, i.e less of tyre touches the road.
second, a top of the range mtb will out perform a top of range hybrid(700c wheels with mtb gear ratios). that site is poor it doesnt take into account the fact joe blogs cant measue the efficiency of drive train.****e bikes (sub e250) have really crap hubs and bearings and everything else, which add to friction, better bikes have better bearings which add to speed,strength and less maintenance.
alot of xc bikes have a feature which allows the front forks to lock out and become rigid, the only mtb to use on road is a xc bike. downhill,dirt jump etc aint designed for speed on tarmac, the xc bikes are the closest thing to riding on tarmac.
if you get off your bike to get up kerbs, over objects....learn how to ride a bike...start with bunny hop.
control your speed coming to traffic lights as not to stop at them roll slowly and sprint on green.
tbh if your spending less than e250 on a bike , they are all the same ****e, so just get the cheapest.
if you get a decent xc bike i guarantee you will out run a decent hybrid.

to go faster somtimes you can just shift up and pedal harder!!!!

and if you wanna keep the weight down...run cycling wont do much for you unless you spend hours in the saddle or do alot of jumping and cross country.

my xc bike has 1.95 and my jump bike has 2.125 and when the jump bike is on the road i can notice the difference when freewheeling. 1.95 are good for roads but dont touch over 2.0 if you wanna use the bike on the road

Trojan

kona wrote:

i hate when people ask this stoopid question.
a proper racer takes upto 100psi a mtb tyre takes 45psi max

No, stoopid, a 26x1.3 Continental Sport Contact can run at 85psi. Oh wait, you didn't mean slicks, right?

Continental Marketing Blurb wrote:

Continental Sport Contact

The SportContact is one of the fastest mountain slicks on the market. Its rolling resistance is so low, that it rivals some road tires. At only 370g this tire is a great buy.

26x1.3, 26x1.6, 85 PSI Max, Wire bead, Weight: 370g(26x1.3).

Can't disagree with the rest of your post, you're spot on.

Here's my MTB set up for fast road travel - and loaded touring, eh?

cerebus

kona wrote:

i hate when people ask this stoopid question.
a proper racer takes upto 100psi a mtb tyre takes 45psi max

Hold on there tiger.

I have three bikes downstairs that disagree with you - a Rocky full-sus running IRC Mythos-XC (good to 60psi), a Rocky hardtail with Maxxis Mobsters (good to 65psi) and my better half's Stumpjumper FSR with Specialized tires good to 80psi.

I believe you may be talking through your hat in this particular case.

blorg

kona wrote:

second, a top of the range mtb will out perform a top of range hybrid(700c wheels with mtb gear ratios).

I don't know where you're getting this from. _Presuming_ the same gear ratios a hybrid will travel further for a given cadence than an mtb, given the larger wheels. Further, "top of range" hybrids tend to have road bike gearing, which will give you a further advantage. But in reality the comparison is meaningless, it only makes sense to compare two actual bikes. I don't deny that you can make a mountain bike fast on tarmac but there is a bit of round peg square hole about it, it's not what the thing was designed for.

I'd certainly say you will get a fast hybrid cheaper and easier than you'll get a comparably fast mountain bike.

Alkers

What about a Cyclocross bike? Similar to a road bike speed-wise but a lot stronger to take the abuse of the commute.

ciaranr

Just a quick one, but is anyone definitely sure about the benefits of an MTB over a road bike with grooved (i.e. not entirely slick) tyres in rain or ice? I get the feeling that, with sufficient care in both cases, a road bike is better in rain but only slightly worse in ice than an MTB. If you look at the physics, a road bike is exerting a higher pressure (pounds per square inch or whatever unit you are having yourself) on the ground than an MTB, and does this higher pressure not help gain better grip on wet pavement? I'm considering urban areas and roads only here of course.

Just a thought

Ciaran

cunnins4

On the whole MTB slower than a Hypbrid and vice versa. You can have the fanciest bike around, but unless you have the legs to move it, it's just another piece of metal. I recently did my first triathlon on my Specialized Hardrock XC (rigid front), and i overtook a load of roadies in the race, but it took a lot more work from me because i had awful gearing, wider tyres (26X1.25), my bike was less aerodynamic, and the wheels are 26'' as opposed to the 700's the roadies have, not to mention the extra weight. Had i used a tri/road bike, i would've gone a lot faster.

As for the ice and rain thing, on the 1.25's i take wet sharp bends with ease, unless there's a lot of road markings. On ice, i would literally come to a snail's pace on any bend because even with knobbies i used to go over. Dunno about road tyres, but the 1.25's are fine. I pump em up to 100psi, and they fly. I will however invest in a road bike soon, because i would get the use out of it and get the speed they're designed for.

Morgan

Neither bike will have any grip on ice (studded tyres excepted) so they'd be pretty equal. Wet tarmac isn't particularly slippery on a bike, unless you're cornering on wet leaves, painted road markings, manhole covers etc.

Gavin

http://www.sheldonbrown.com/tires.html#tread

Civilian_Target

Yeah - a oil-covered man-hole cover almost took me into the back of a car today, was not amused!

If you have good tyres at a high pressure, you should have few puncture problems. I'm running Specialized Armadillos at about 95psi and nothing has penetrated them since I got them almost a year ago.

blorg

Second the Armadillos, I went three years on 700x26 ones without a single puncture.

kona

blorg wrote:

I don't know where you're getting this from. _Presuming_ the same gear ratios a hybrid will travel further for a given cadence than an mtb, given the larger wheels. Further, "top of range" hybrids tend to have road bike gearing, which will give you a further advantage. But in reality the comparison is meaningless, it only makes sense to compare two actual bikes. I don't deny that you can make a mountain bike fast on tarmac but there is a bit of round peg square hole about it, it's not what the thing was designed for.

I'd certainly say you will get a fast hybrid cheaper and easier than you'll get a comparably fast mountain bike.

in stop start cycling i.e(the city) a mtb will out perform a hybrid, irregularities in the road dont slow it down, the smaller wheels promote greater acceleration.
a hybrid with road bike gear ratios is called a road bike.
no proper mountain bike tyre is slick.
tbh in my opinion if you use your bike on the road buy a road bike(racer or tourer) if you off road get a mtb. hybrids are mongrels/mules
.
yes mtb tyres can go over 45psi but most people here commuting run 45psi as they dont buy expensive off road machines.

Alkers

You can easily kit out any mountain bike with 26" slick tyres more than capable of running 45psi - it's nothing to do with how expenisve your mtb is. I use a mtb for commuting, I don't like the geometry of road bikes, find them very uncomfortable and dislike their handling, especially for use in traffic. If you get a decent lightweight mountainbike and slick tyres - that to my mind is the ideal bike for commuting.

Trojan

kona wrote:

in stop start cycling i.e(the city) a mtb will out perform a hybrid, irregularities in the road dont slow it down, the smaller wheels promote greater acceleration.
a hybrid with road bike gear ratios is called a road bike.

Claud Butler Levante 2006 Hybrid Bike.

kona wrote:

no proper mountain bike tyre is slick.

Here's 50.

kona wrote:

tbh in my opinion if you use your bike on the road buy a road bike(racer or tourer) if you off road get a mtb. hybrids are mongrels/mules

Depends on the road conditions and route. My MTB with slicks is faster and more comfortable on my commute from Artane to East Point than my tourer is because I need to pick my route carefully on the 700x28s.

kona wrote:

yes mtb tyres can go over 45psi but most people here commuting run 45psi as they dont buy expensive off road machines.

That doesn't really make any sense to me. There's plenty of tyres at that link I've just given that go way over 45psi.

rubadub

kona wrote:

tbh in my opinion if you use your bike on the road buy a road bike(racer or tourer) if you off road get a mtb. hybrids are mongrels/mules.

Depends on your definition of "road":D
I obey the law and cycle in cycletracks, a road bike is extremely uncomfortable on my regular commute, it is even a bit rough on a rigid forked MTB. Many "roads" here are almost like light off road trails! The government knows this and thats why the gardai are issued with MTBs, they know road bikes wouldnt last pissing time.

kona

you show me a proper mtb..... kona, orange, norco, santa cruz with slick mtb tyres standard.
as i said personally i prefer mtb over road bike, but you dont buy a jeep to drive in the city.....oh wait:rolleyes:
lads its a stupid topic and NO mtb was designed to run slicks unless its a nutjob rider who likes wheels to spin in dirt.
the slick tyres were brought out to satisfy commuters,
show me a sub e200 with standard tyres that go over 50 psi
no the gardai are issued with mtbs because of the amount of gear they carry on the back. ffs they were not even trained to use them they are always in the wrong gear, the tyres aint inflated proper, tbh they are a joke.
irish roads are **** roads not light off road trails, howth has a light off road trail...try it, you will think roads are piss.

blorg

Kona, have you ever actually cycled a hybrid, for a given price point, same rider, they are generally going to be quicker than a mountain bike on typical roads (certainly if the MTB includes suspension) but are (IMHO) often a sensible choice for someone who wants to avoid drops. They are a certainly a good choice for commuting. I have drops myself now on my main bike but have cycled Dawes/Trek/Specialized hybrids for over ten years commuting (with a Trek 1000 road bike alongside for some of that.)

The whole "hybrid is a mongrel" cráp is exactly that, a hybrid can be a perfectly good compromise and makes a hell of a lot more sense on road than a mountain bike. Agree completely that optimum is road bike/tourer for road, MTB for off-road, but as you say buying an MTB for on-road use only IS exactly like buying a jeep for city driving. If you buy a nice light expensive MTB for off-road, then sure it makes perfect sense to use it also for commuting, but buying one specifically for road use makes no sense.

I also don't understand exactly where everyone is cycling that the roads are _so_ bad that they can't tackle them without an MTB. I cycle all over Dublin and sure the roads are cráp but with the exception of the "bouncy driveway" cyclepaths (which I simply don't use) it is all perfectly cycleable on 700x26/28 tyres inflated as hard as I can! Hint: get a pair of padded cycling gloves!

I have tacoed a wheel going over 30 into a _monster_ pothole but I honestly think it would have been the same on an MTB - unless of course the MTB would have slowed me down enough to avoid it

OP- get Specialized Armadillos and you won't have to worry about the punctures, mountain bike or no.

rubadub

kona wrote:

you show me a proper mtb..... kona, orange, norco, santa cruz with slick mtb tyres standard.

Most people buying a proper MTB want it for MTB cycling, it would not make much sense for them to supply them with slicks as standard. Doesnt mean they are no slicks available for MTBs, as somebody else posted some shops have entire categories of them, must be some demand.

kona wrote:

lads its a stupid topic and NO mtb was designed to run slicks unless its a nutjob rider who likes wheels to spin in dirt.

For a stupid topic it is getting a fair few replies. This topic was about efficiency of one bike over another. I also think of the advantages a MTB may have such as comfort, reduced punctures, safety, stronger components, able to go faster on dodgy roads. All of these could lead to your yearly time commuting to actually being faster, like I mentioned I had 4 punctures in the last few months.

Some would argue the current MTB narrow rims (as standard) are unsuitable to the big widetyres being put on them.

kona wrote:

irish roads are **** roads not light off road trails, howth has a light off road trail...try it, you will think roads are piss.

I was joking/exagerrating.

blorg wrote:

I also don't understand exactly where everyone is cycling that the roads are _so_ bad that they can't tackle them without an MTB. I cycle all over Dublin and sure the roads are cráp but with the exception of the "bouncy driveway" cyclepaths (which I simply don't use)

The majority of my cycling is on the cyclepaths that you do not think are fit to use, thats why some people think cycling while obeying the law requires a MTB if you want it to last and be at all comfortable.

The armadillos are on offer here
http://www.evanscycles.com/product.jsp?style=10052

I wonder how they compare to these, I would prefer a thicker tyre
http://www.evanscycles.com/product.jsp?style=10051

blorg

rubadub wrote:

The majority of my cycling is on the cyclepaths that you do not think are fit to use, thats why some people think cycling while obeying the law requires a MTB if you want it to last and be at all comfortable.

Ah OK, you'll be needing full suspension in that case Seriously, I'm not sure that there is a real solution to using _those_ cycle paths other than simply going slower, I don't know that you would be able to get up to a decent speed on a hardtail. Any reason not to just use the road? I got a mirror specifically for these paths so I could use the bus lane and still see buses coming up behind me so that I can get out of their way. What is your commute by the way?

rubadub wrote:

The armadillos are on offer here
http://www.evanscycles.com/product.jsp?style=10052

I wonder how they compare to these, I would prefer a thicker tyre
http://www.evanscycles.com/product.jsp?style=10051

The Armadillos are a step up from the Flak Jacket; some suggest that the difference extends to the Armadillos also protecting the sidewalls, others suggest that it is a completely different and more effective system.

Besides my own experience I have seen a _lot_ of great things on the internet specifically about the Armadillos, to an extent that I have not seen for any other tyre. LBS replaced them with Vittoria 700x28 kevlar in mid-August. These have not been anywhere near as puncture resistant and I've had three or four flats over around 5,600km. I think I will be going back to the Armadillos!

kona

rubadub wrote:

Most people buying a proper MTB want it for MTB cycling, it would not make much sense for them to supply them with slicks as standard. Doesnt mean they are no slicks available for MTBs, as somebody else posted some shops have entire categories of them, must be some demand.

yes i never said they wernt available i said NO proper mtb comes with them.
tbh a cheap mtb on the road is equally as sheet off, i wouldnt trust the brakes on them to stop me in a instant in the dry or wet.
eh no most people cycle on the roads to get to the trails to do off roading so the bikes are used on the road.

rubadub wrote:

For a stupid topic it is getting a fair few replies. This topic was about efficiency of one bike over another. I also think of the advantages a MTB may have such as comfort, reduced punctures, safety, stronger components, able to go faster on dodgy roads. Some would argue the current MTB narrow rims (as standard) are unsuitable to the big widetyres being put on them.

if i posted a thread on how great my pedals are it would get alot of replies really quick, and that would be a really stupid thread.
that puncture angle is bull****, it has more to do with luck, i rarely get punctures, however the lads in work have been going through a bad patch where they are getting lots. i dont think bits of glass discriminate.
manufacturers wont put a tyre on a wheel that is too small, if they do they get sued. as with boy racers, a bike is designed to run a size of tyre if you change the size of tyre the bike doesnt work right.

all bikes are close to 100% efficiency so to answer the question of the thread...you get out pretty much what you put in

rubadub wrote:

The majority of my cycling is on the cyclepaths that you do not think are fit to use, thats why some people think cycling while obeying the law requires a MTB if you want it to last and be at all comfortable.

read the rules of the road, as a road user cyclists dont have to use that little ****ty piece of red gutter provided, if i need to use the road i will , **** the yuppies in their warm dry cars, they can either (i)wait or (ii) overtake me.
sure wouldnt you be breaking the law everytime you want to turn right;)