MTB vs Road Bikes

[davetapson]

2:48

See now there's a man who can give an answer!!

 

None of this vacillating 'depends on the air pressure, humidity on the day, plus the specific gravity of the Hansas enticing one to the finish...'

 

Would have preferred seconds as well, but I can live with just minutes

 

Who reckons he's in the ball park?

[davetapson]

15% = 3:24

20% = 3:12

25% = 3:00 flat.

 

Ok, interesting...

[Iron]

Last year on my road bike 2:48

This year on a single speed mtb with knobby tires 3h18.47

 

Help me out math guru's , this is 28% diff , give or take

Edited November 21, 2011 by Iron

[Pieterg]

75% Harder on a MTB

[davetapson]

In MTB, bike price makes a huge diffs in what you get - rigid to full susp, suspension components etc which makes a diffs on off-road.

 

With road bikes (on tar, Witkop) is there a real difference in the performance of a R10k bike compared to a R20k bike? Surely, in real terms, the only REAL advantage for the price is going to be a lighter bike? The rolling resistance is not going to be significantly different. And even then the difference is going to be pretty marginal?

[davetapson]

Last year on my road bike 2:48

This year on a single speed mtb with knobby tires 3h18.47

 

Help me out math guru's , this is 28% diff , give or take

I get about 15%. Doesn't sound much, but equates to half an hour.

[Vinnydabutcher]

I would say MTB 4:00 = Road 3:30

 

My reasoning - rolling resistance/weight/aero of position of MTB is a drawback - however, in the bunch its mostly rolling resistance as the aero in cancelled but the draft/slipstream of the group. The weight coefficient is less to overcome in the group because the drag is less.

 

This is a final exam long question but my money will be on around 3:30 - but if you get a big group and can stick with them - 03:15 could be on the cards.

 

Hope it helps.

[davetapson]

I would say MTB 4:00 = Road 3:30

 

My reasoning - rolling resistance/weight/aero of position of MTB is a drawback - however, in the bunch its mostly rolling resistance as the aero in cancelled but the draft/slipstream of the group. The weight coefficient is less to overcome in the group because the drag is less.

 

This is a final exam long question but my money will be on around 3:30 - but if you get a big group and can stick with them - 03:15 could be on the cards.

 

Hope it helps.

Thanks. Yep, I found that if I was tucked in a bunch, all was cool. The problem was hills, where the reduced weight / reduced rolling resistance of the road bikes gave them an advantage.

[Witkop]

I would say MTB 4:00 = Road 3:30

 

My reasoning - rolling resistance/weight/aero of position of MTB is a drawback - however, in the bunch its mostly rolling resistance as the aero in cancelled but the draft/slipstream of the group. The weight coefficient is less to overcome in the group because the drag is less.

 

This is a final exam long question but my money will be on around 3:30 - but if you get a big group and can stick with them - 03:15 could be on the cards.

 

Hope it helps.

 

 

On a Mtb race

MTB=2hrs

road = broken bike and hospital bills

 

At the first river crossing at Fountains the road bikes front wheel will wash out and buckle, depositing the rider onto the rocks in the river, resulting in lacerations and maybe a broken bone.

 

Please guys stop comparing apples with pears. A mtbike is for off road and a road bike is for on road and a track bike is for the track. To compare each bike against the other is impossible as they were designed for different conditions. But maybe the answer is to do a comprehensive testing of road vs mtb.

 

We start ith a classic like the 94.7 and then take the same bikes and run them at van Gaalens for 24 hours (which will give us some good data to work with, with lap times, different riders ext). Finally we can look at a hybrid race like the crater cruise. From that we will prove that on the road leg strength and riding tactics make a diference, and on mtb routes (especially cross country lap racing,) leg strength and bike handling stills are requires.

[Stefanh]

also, when you look at going downhill for example, at 60kph i was peddled out and there was absolutely no way i could keep up, the roadies was flying at about 75-80kph still peddling, in my opinion. gearing makes a huge difference. the momentum gained going downhill will make you reach further up the next hill before you have to stark working going up and the mbt will have to start working way further back.

[Headshot]

best argus on a road bike - 2h58, best on MTB with slicks - 3h25. so many variables, its meaningless really. I was 8 years older for the mtb time and the distance was 5km longer. Gearing definitley makes a difference as do drop bars and being able to slipstream with low rolling reistance helping out too.

[Minion]

Which probably why roadies have such a infatuation on trying to make such calculations.

Yet, every time, it's a MTBer asking variations of "If I can do x on my MTB, what can I expect to do if I'm on a road bike". Or does the mere contemplation of the tar immediately disqualify them from the ranks of true offroaders?

[davetapson]

Yet, every time, it's a MTBer asking variations of "If I can do x on my MTB, what can I expect to do if I'm on a road bike". Or does the mere contemplation of the tar immediately disqualify them from the ranks of true offroaders?

Heh heh. But doesn't make much sense to ask 'If I can do Barberton in 4hr on my MTB, how long would it take on a road bike?' (I can answer that 10hr, as long as you carry it most of the way...)

[El Dodgius Bastardo]

15% faster on a Morewood

[banna]

15% faster on a Morewood

 

*** brew. At least 50%.