Iggz79

Hi guys,

I'm a new member who signed up due to a Crash Last weekend.
I lost front wheel traction right in the apex of a faster curve. Incident happened right After i decided to pump up my bontrager 23 race r3 front tyre to 105 psi and 115 psi for the rear. Usually 90 and 100 psi for front and rear tyres respectively is my maximum. Im 72 kg Advanced recreational cyclist with big bruises randomly spread over right side of my Body and a massively sore hip now... Did i lose front wheel grip cause of that higher pressure while taking same curve with similar speed ? I took that same curve dozens of times before and never expected this to happen. Reason I tried higher pressure is all this recommended hype in Forums and Web about 100 psi for front and 110 rear being normal for my weight range and 23 tyres. Is It really that normal in dry conditions? Any similar experience or Good article on this ??

Thanks !

on the path

I seriously doubt it. Probably something on the road surface.. water, gravel, oil slick?

rpenmanparker 

Where did you get the idea those pressures were proper for your weight? They seem very high to me. But many of us have ridden even higher pressures over the years. That wasn't it.

datlas 

Pressure was too high but probably not the cause of your crash. Probably not, but impossible to "prove."

I hope you heal up. Drop back to 90F 100R.

Iggz79

Thanx for quick reply. Strangely rear tyre Ticked a little, drifting for a few cm. Caught that and then within a break of a sec After front skipped and Was gone Too. Could be oil or another liquid from a Truck or car indeed . That road is very busy in september.. any tips on what to Do if It WAS oil or car liquid . breaking is Too late or maybe straightening up quicker ? Dont you think that with lower pressure i would have Had more chances to correct It ? Or if **** Hits the Fan nothing We can Do. It definately wasnt visible in advance ...


In any case thank you all and surely am going back to lower pressure - for superstition's sake

rpenmanparker 

Sometimes the asphalt just needs a little kiss, and you are nominated to provide it.

Iggz79

Very true! LOL

Bob Dopolina 

Pressures were appropriate and not related to the crash.

Brian Ratliff

^^^
Yup. My thoughts exactly.

powbob

Try a little cyclocross riding. Little skids will become no problem quickly.

Dean V

True, but if the front washes out properly you are on the ground no matter how good you are.

Homebrew01

User error

bruin11

So we can understand. You were in a high speed turn with the bike leaned over and the rear started to slide a little so you grabbed the brakes for a sec. That is why your front tire went if I read that correctly.

Iggz79

Nope, didnt touch brakes at all. Was in the apex when rear lost traction for a bit but managed to stabilize. Front lost grip right after that . All happened within a sec or so. Must have been oil or liquid on the road randomly spread over that curve. Higher tyre pressure and that crash was a coincidence I believe now. I didnt take the time to inspect the surface after falling but there was definately some blood stains as well Thanks guys

StanSeven

I think comments about pressures being high are not realizing the tires are 23s. The pressure is just right for the OPs weight.

alexaschwanden

Slow down in the turns.

EvilWeasel

Higher tire pressure will result in a smaller contact patch, but we are talking fractions of centimeter here. Less tire flex as well, and that might slightly change cornering feel. The pressure seems right. Maybe you just got caught out by a change in road feel?

StanSeven

I was curious and looked at manufacturer web sites- Conti, Michelin, and Schwalbe, and you are right in line with pressure for your weight.

rpenmanparker 

158 lb rider needs 100-105 psi on the front?

Bob Dopolina 

Yes, that would be optimal for rolling resistance, tire wear and puncture resistance according to the folks who actually design and manufacture the tires.

If you wanted to give up a little bit of those in favour of increased comfort then a drop to 95psi would do the trick.

rpenmanparker 

I asked because a chart I was looking at showed 72 psi for the front according to a 40/60 weight split. I use more like a 45/55 theoretical split, but still don't approach 105 psi.

UmneyDurak

If traction is compromised, dust, wet stuff on the ground, some car spewed oil all over the place you want to minimize lean angle.
This can be accomplished by either a different choice of line, going through the corner slower, body positioning. Straightenning up is possible, depending if you have room or not. Just be careful not to target fixate on other side of the road and run off the road. So try to continue looking through the corner. Also during descending try to have your weight on the pedals in a straight line or weighting outside pedal on a turn. Your legs will act as suspension and help to absorb some of the bumps.

Bob Dopolina 

That stupid Bertol or Betrand or whatever the heck that guy's name was chart is stupid. It has been hacked to shreds more time that a busty blonde in a slasher film.

Weight distribution is not static, it is dynamic. Tire drop or % distribution methods make no sense in the real world.

Also, tires are DESIGNED and Manufactured to function at the intersection of all factors within a specific range. I think the manufacturers know best what those are.

rpenmanparker 

Yeah, I know the charts make no sense for the real world. For about a year now 90/100 has been working well for me. That's all that counts I guess.

gsa103

If the tire contributed at all, it would only be a tiny tiny difference. The tire were maybe 5-10 psi high, not enough to matter in any realistic sense. I'm close to the OP's weigh and for a while was simply inflating the tires to max in search of lower rolling resistance. That meant I was routinely riding at 130 psi. There simply isn't that much difference in handling.

And the 40/60 distribution/chart is worthless. I tried it once, the bike handled like crap because as soon as you braked the front tire squirmed all over the place. Manufacturer recommended pressure charts are a much better guide.