Tyre choice for adventure riding? (Mixing road and off-road)

**warewolf** · 7th October 2012, 19:00

Originally Posted by Padmei

Gravel riding with road biased adv tyres on a heavy bike.
Better to have less pressure & have more contact patch with the tyre deforming & roll sideways as you corner or normal pressure & have the tyre kinda cut in to the gravel with minimal roling?

"tyre deforming & roll sideways" sounds a little sketchy to me. If that's happening, sounds like not enough pressure. The idea is to have a little more give in the tyre, as a result it will feel a little squishy but not severely or unsettlingly so.

Bear in mind that you have two tyres to get you through the corner. Four strokes load up the front when you shut the throttle. Usually you want to use a little throttle to balance the bike front-to-rear and get both tyres working, that is, in order to avoid over-loading the front. The rear has a bigger contact patch and you want to make use of it. I spent an afternoon on an R100GS earlier this year, did about 100km of gravel road, everything from deep loose goolies to flat hard pack and bouncy rough stuff. It was terrible in corners on a closed throttle, definitely needed a bit of drive from the rear to keep the plot under control. And this bike had fancy after-market suspension, too.

**george formby** · 8th October 2012, 12:06

Originally Posted by warewolf

Bear in mind that you have two tyres to get you through the corner. Four strokes load up the front when you shut the throttle. Usually you want to use a little throttle to balance the bike front-to-rear and get both tyres working, that is, in order to avoid over-loading the front. The rear has a bigger contact patch and you want to make use of it. I spent an afternoon on an R100GS earlier this year, did about 100km of gravel road, everything from deep loose goolies to flat hard pack and bouncy rough stuff. It was terrible in corners on a closed throttle, definitely needed a bit of drive from the rear to keep the plot under control.

That paragraph pretty much sums up how to ride an Adventure bike.

**warewolf** · 8th October 2012, 18:39

Originally Posted by Woodman

Does anyone ever stop and change their pressures when changing from road to gravel and vice versa?

Only if there is a protracted road transport before or after the dirt, in which case I'll set off running full road pressures, then drop them at the first dirt, then re-inflate before the slog home. But more likely I'll be on-and-off the dirt all the way there and back instead!

**warewolf** · 8th October 2012, 19:28

Originally Posted by Transalper

If in doubt go for a ride with 'your' heavy bike and 'your' sealed road bias tyres, full road pressures, go on some gravel bends etc, then circle round, drop 5 or 10psi and go again. Drop more and play more if needed, then pump them back up and see if it turns to crap when you go again.
Testing your own setup should give you the best answer for you.

This. But in smaller increments, say 2 psi, as 0.5 psi can make or break. The idea is to chip away at the pressures rather than make radical changes. As an aside, one of the reasons Mick Doohan was so successful was his sense of speed. It was said that a GP racer could set/lift their speed by only 1/4 mph, the idea being they'd approach the limit without over-stepping it, or at least while it was recoverable. But Mick could improve by closer to 1/10 mph and therefore reliably stay just that little bit closer to limit, and thus be faster and crash less. But I digress.

Just get yourself into the groove with the bike, say 30 mins on gravel, then jump off and let a little air out, don't measure just do a few presses of the valve core, and then ride some more. Repeat until it feels worse not better, and then measure what they are at hot (for curiosity's sake more than anything), and again when cold as that's how you set your measured pressures. Now you have a rough figure to refine on your next ride. Start a few psi higher than the good rough figure from last time, but this time be more subtle with the pressure drops. This technique should help you to develop a greater feel for the effect of pressure, and also feel for the tyre's grip. You may find that your perception of grip changes as you concentrate on it more, and you may end up choosing different compromises.

Just remember that if the load, terrain, suspension or tyre changes, you'll have to repeat the exercise!

PS You've already done this to set your road pressures, right?

**warewolf** · 8th October 2012, 19:36

Originally Posted by george formby

That paragraph pretty much sums up how to ride an Adventure bike.

And road bikes; the big difference being - at least for us mortals - in slow corners, on the dirt rear-wheel steering comes in to play, whereas on tar closing the throttle drops the bike into the apex.

**NordieBoy** · 8th October 2012, 19:37

Originally Posted by warewolf

Just remember that if the load, terrain, suspension or tyre changes, you'll have to repeat the exercise!

And then you go for a ride and take a photo for the Top Of The South Tag...

**warewolf** · 8th October 2012, 19:41

Originally Posted by NordieBoy

And then you go for a ride and take a photo for the Top Of The South Tag...

Subtle as a brick, Nordie!

**10bikekid** · 8th October 2012, 21:13

Can be a bit hard to put into words, but the number one safety tip would be stay in the left groove untill you have clear visability

I think this can also work well to keep up a good pace as for example heading into a blind right hander you run deep into the corner before turning therefore increasing your visability around the corner and once its clear quickly cross the ridge by squaring off the corning, reducing the time your front wheel is scatting across the loose stuff,

Left hander can be done pretty much the same way by hugging the left groove as long as possible, seen a few guys gas it to early and drift out into the loose pushing the front end then the rest of the bike into harms way if there was oncoming traffic (not to mention it being a slower way around the corner)

Would also recommend grabbing a mates dirt bike, head for a track and learning to use your body weight to seesaw from front to back to learn to search out the required grip, this can be another great way to improve safety and pace in the metal without the risk associated with getting it wrong out there in the big wide world where cars roam

IMHO: :confused: