In an attempt to get the gf's MTB to keep up with my hybrid I've been pumping up tyres to higher pressures to make sure the rolling resistance is at minimum. I've put her rears up to 65psi (max stated on the rim) and 60psi at the front. With the fat tyres and suspension forks she hasn't noticed anything untoward.
I've also ramped up my hybrid 700c tyres a bit as well to 80psi rear (85 max rated) and 70psi front. It's definitely a 'bouncier' ride, but only really noticable when on rougher ground (stony, pot-holy tracks to birding sites).
What's the line on tyre pressures? Am I too high, too low or is it personal preference above a certain minimum? How much should they come down (%age) when going 'off road'? From reading around it seems higher is generally faster but I've had a hard time finding any figures.
Cheers, Frink
-- Doctor J. Frink : 'Rampant Ribald Ringtail' See his mind here : cmp.liv.ac.ukfrinkOpen ↗ Annoy his mind here : pjf at cmp dot liv dot ack dot ook "No sir, I didn't like it!" - Mr Horse
In an attempt to get the gf's MTB to keep up with my hybrid I've been pumping up tyres to higher pressures to make sure the rolling resistance is at minimum. I've put her rears up to 65psi (max stated on the rim) and 60psi at the front. With the fat tyres and suspension forks she hasn't noticed anything untoward.
I've also ramped up my hybrid 700c tyres a bit as well to 80psi rear (85 max rated) and 70psi front. It's definitely a 'bouncier' ride, but only really noticable when on rougher ground (stony, pot-holy tracks to birding sites).
What's the line on tyre pressures? Am I too high, too low or is it personal preference above a certain minimum? How much should they come down (%age) when going 'off road'? From reading around it seems higher is generally faster but I've had a hard time finding any figures.
Swap the MTB tyres to slicks or semi slicks if you haven't already. Makes much more difference than trying to run knobblies at silly pressures.
In an attempt to get the gf's MTB to keep up with my hybrid I've been pumping up tyres to higher pressures to make sure the rolling resistance is at minimum. I've put her rears up to 65psi (max stated on the rim) and 60psi at the front. With the fat tyres and suspension forks she hasn't noticed anything untoward.
I've also ramped up my hybrid 700c tyres a bit as well to 80psi rear (85 max rated) and 70psi front. It's definitely a 'bouncier' ride, but only really noticable when on rougher ground (stony, pot-holy tracks to birding sites).
What's the line on tyre pressures? Am I too high, too low or is it personal preference above a certain minimum? How much should they come down (%age) when going 'off road'? From reading around it seems higher is generally faster but I've had a hard time finding any figures.
Some mountain biking people run their tyres quite soft - 30psi or even less. But I think these are mainly people who are using their bikes for quite short blasts around woodland. There's no doubt that softer tyres can help with traction on very soft or loose going, but in general the harder the tyres the lower the rolling resistance and for off-road cross-country stuff I tend to aim for 50-55psi. On my road bike I run at 110psi but that's on little skinny tyres.
In an attempt to get the gf's MTB to keep up with my hybrid I've been pumping up tyres to higher pressures to make sure the rolling resistance is at minimum. I've put her rears up to 65psi (max stated on the rim) and 60psi at the front. With the fat tyres and suspension forks she hasn't noticed anything untoward.
Swap the MTB tyres to slicks or semi slicks if you haven't already. Makes much more difference than trying to run knobblies at silly pressures.
That's Step 2.
The appeal of higher pressures (amongst other low-cost resistance reducing efforts such as eliminating brakes catching on rims, lubrication etc) is that it costs nothing but quite literally fresh air ;0). Also reduces flats, allegedly.
Step 3 (or maybe 1b) is to get GF pedalling faster and braking less. Easier said than done.
Frink
-- Doctor J. Frink : 'Rampant Ribald Ringtail' See his mind here : cmp.liv.ac.ukfrinkOpen ↗ Annoy his mind here : pjf at cmp dot liv dot ack dot ook "No sir, I didn't like it!" - Mr Horse
In an attempt to get the gf's MTB to keep up with my hybrid I've been pumping up tyres to higher pressures to make sure the rolling resistance is at minimum. I've put her rears up to 65psi (max stated on the rim) and 60psi at the front. With the fat tyres and suspension forks she hasn't noticed anything untoward.
I've also ramped up my hybrid 700c tyres a bit as well to 80psi rear (85 max rated) and 70psi front. It's definitely a 'bouncier' ride, but only really noticable when on rougher ground (stony, pot-holy tracks to birding sites).
What's the line on tyre pressures? Am I too high, too low or is it personal preference above a certain minimum? How much should they come down (%age) when going 'off road'? From reading around it seems higher is generally faster but I've had a hard time finding any figures.
You can pump them up to the max pressure marked on the tyre. But have you considered the option of slowing down to cycle with your gf? It can be very dispiriting and off- putting to have someone racing away all the time and telling you to go faster. Togetherness is riding at the slowest person's speed.
What's the line on tyre pressures? Am I too high, too low or is it personal preference above a certain minimum?
I generally run at or near maximum stated as that gives lower rolling resistance. This probably bites me a little on technical stuff on the MTB, as does keeping the saddle set high, but I'm generally covering ground rather than especially fiddly things and I'm so used to high pressure tyres that floppy balloons annoy me a lot where they're not useful.
Quoted message said:
How much should they come down (%age) when going 'off road'?
It'll depend on the sort of off-road. Work it empirically: try not letting any out, and see how you get on; should be okay as long as you're not Going For It. I've never felt any real need to let down the MTB tyres, so haven't. If the 'bent or Brompton goes onto a forest track for a while it's a bit silly as with 100 psi the bike tends to jump sideways and ping wee stones out of its way a fair bit. Any more than a few miles of that and I'd think very hard about letting a bit out.
Pete. -- Peter Clinch Medical Physics IT Officer Tel 44 1382 660111 ext. 33637 Univ. of Dundee, Ninewells Hospital Fax 44 1382 640177 Dundee DD1 9SY Scotland UK net [email hidden] dundee.ac.uk~pjclinchOpen ↗
"Tony Raven" <[email hidden]> wrote in message "]news:[email hidden]...
Quoted message said:
But have you considered the option of slowing down to cycle with your gf? It can be very dispiriting and off- putting to have someone racing away all the time and telling you to go faster. Togetherness is riding at the
slowest
Quoted message said:
person's speed.
And Tony also knows the answer to this - get a tandem!
In an attempt to get the gf's MTB to keep up with my hybrid I've been pumping up tyres to higher pressures to make sure the rolling resistance is at minimum. I've put her rears up to 65psi (max stated on the rim) and 60psi at the front. With the fat tyres and suspension forks she hasn't noticed anything untoward.
You can pump them up to the max pressure marked on the tyre. But have you considered the option of slowing down to cycle with your gf? It can be very dispiriting and off- putting to have someone racing away all the time and telling you to go faster. Togetherness is riding at the slowest person's speed.
This is exactly what I do. She goes in front, I tail her rear wheel. It was mostly the difference in freewheeling downhill; I'm hard on the brakes trying not to whizz past.
Frink
-- Doctor J. Frink : 'Rampant Ribald Ringtail' See his mind here : cmp.liv.ac.ukfrinkOpen ↗ Annoy his mind here : pjf at cmp dot liv dot ack dot ook "No sir, I didn't like it!" - Mr Horse
"Peter Clinch" <[email hidden]> wrote in message "]news:[email hidden]...
Quoted message said:
Doctor J. Frink said:
What's the line on tyre pressures? Am I too high, too low or is it personal preference above a certain minimum?
I generally run at or near maximum stated as that gives lower rolling resistance. This probably bites me a little on technical stuff on the MTB, as does keeping the saddle set high, but I'm generally covering ground rather than especially fiddly things and I'm so used to high pressure tyres that floppy balloons annoy me a lot where they're not useful.
I find one of the biggest benefits of full suspension on VTTs is being able to run realistic tyre pressures because the tyre is no longer responsible for doing the ride cushioning as well as supplying the traction.
Since going full-sus I am able to run the same kinds of tyres about 10 or 15 psi higher for the same comfort and a lot fewer pinch flats but with better steering.
Bike's even more difficult to carry though :-( -- Mark South: World Citizen, Net Denizen
This is exactly what I do. She goes in front, I tail her rear wheel. It was mostly the difference in freewheeling downhill; I'm hard on the brakes trying not to whizz past.
Slicks should really help here. Not only can you roll quite a bit faster but you actually get more effective control (and feel of control IME) for cornering and the like because you've got continuous contact rather than a succession of distinct knobs. With more control, less feeling of a need to brake.
Mt MTB has big knobblies on which are great on soft stuff but they're a total PITA on the road, making riding harder, slower and noisier than I'm used to.
Pete. -- Peter Clinch Medical Physics IT Officer Tel 44 1382 660111 ext. 33637 Univ. of Dundee, Ninewells Hospital Fax 44 1382 640177 Dundee DD1 9SY Scotland UK net [email hidden] dundee.ac.uk~pjclinchOpen ↗
