Snakebite P***tures

W5454

Riding into Otley today I got a SP.To make things worse my undersaddle storage bottle containing spare tubes,levers glue and patches had dissappeared,the bracket had snapped, so I had a 10 mile ride home with a flat rear tyre.
Is there a way to prevent SPs?
I'm using Conti Ultra Gator Skins 700 x 23 @ 100psi.

alfablue

The number one reason for SB's is under-inflated tyres. 100psi sounds enough but the required pressure increases with rider weight. You could probably go a bit hgher.

I think Gator-skins are not as tough as they pretend to be.

redddraggon

How often do you check your pressures?

I used to pump my tyres upto 120psi and then forget about them for weeks and I'd get a snakebite making me think I wasn't pumping them to a high enough pressure, now I pump my tyres to 100ish psi and check them every couple of days.

W5454

redddraggon wrote:

How often do you check your pressures?

I used to pump my tyres upto 120psi and then forget about them for weeks and I'd get a snakebite making me think I wasn't pumping them to a high enough pressure, now I pump my tyres to 100ish psi and check them every couple of days.

I inflate the tyres to 100psi for every ride with a track pump.
After a ride I deflate the tyres.
I'll try 110psi and see how that goes.

dennisn

Heavier weight tubes is one answer. Lots of rubber thickess.
Tubular tires or tubular clinchers are another option. Tubular clinchers by Tufo are
actually tubeless. No pinch flats there.

Dennis Noward

ColinJ

alfablue wrote:

The number one reason for SB's is under-inflated tyres. 100psi sounds enough but the required pressure increases with rider weight.

With respect, I think that is the number two reason (as long as the pressures are not stupidly low).

I think the number one reason for snakebites is not riding carefully enough! I get a snakebite maybe once per 10,000 miles and I run my tyres at about 85-90 psi front and 90-100 psi rear. I'm 6' 1" tall and weigh over 15 stone (215 pounds or 98 kgs).

I don't bump up over kerbs, watch out for stones and other debris in the road, definitely do my best to go round or bunnyhop over potholes, and get out of the saddle with arms and legs slightly bent when going over very rough roads and cattlegrids - it does the trick for me .

Cajun

Do you lightly inflate the tube before placing it on the wheel?? I use my mouth to inflate the tube to give it some body shape before the install...this keeps the tube from doing some folds while installing.... Not sure if this applies to you, but worth a try..

chuckcork

Would suggest the obvious, you hit something hard enough to cause the tyre to pinch against the wheel and puncture the tube in two places. To avoid, inflate tyres to max pressure as indicated on the sidewall, and expect to lose a couple of lb's of pressure per day. I pump mine up (at least) once a week using a track pump that of course has a gauge.

Also, I found with a particular brand I was trying out I was getting a lot of pinch flats, when I had been inflating to the correct pressure, and when I had not been getting them on another brand (Schwalbe Stelvio Plus), so in short order I gave up on that brand and went back to Stelvios, problem solved.

Also as noted watch out for objects on the road, manhole covers, potholes etc, if you can't avoid them then get off the seat to reduce weight on that vulnerable rear wheel.

Though yesterday I hit a large metal buckle of the kind used to secure the side flaps of trucks, hard enough it damaged my front wheel rim, yet no flat. Go figure.

Parsnip49

Max pressure on the sidewall???? NO


The max pressure on the sidewall is the max the manufacturers reccomended - not a target.

Its well known that the Crr or tyres at huge pressure is higher than slightly lower pressure - roads arent smooth, if your tyres are solid (theoretical) then you are going up and down lots of tiny hills constantly, less pressure means you roll over them.

This has nothing to do with punctures, but its good to know

As for the punctures, yes pumping your tyres harder will stop them, but a better option is to pump them up to the manufacturers rating for your weight and look out for debris - plus, your ride will be much smoother than if your riding on solid tyres.

Rich Hcp

If you hit a pothole then you'll probably get a Snake Bite, and you can split the tyre as well

100PSI seems to be about right

W5454

I did the same route today,on the off-chance that I might see my lost storage bottle - no such luck though.
Anyway,when I reached the spot where I got the snakebite,I noticed there was a lot of flint chips in the grass verge and some of them were on the road.Since the road surface is ok at this point I think I must have hit one of these flint chips.
Thanks to everyone for their advice.

Coriander

It should probably be screamingly obvious, but what is a snakebite p***ture?

ColinJ

Coriander wrote:

It should probably be screamingly obvious, but what is a snakebite p***ture?

It's when you hit something in the road so hard that your tyre gets flattened and the wheel rim pinches the inner tube on both sides, 'guillotining' the rubber. This typically produces two parallel little splits in the tube which look like the puncture wounds from a real snakebite.

ColinJ

As discussed above, keeping your tyre pressures high reduces the chance of this happening, but you still risk damaging your tyres if you make a habit of hitting things in the road because you don't look where you're going. I prefer lower pressures and keeping my eyes open. Despite being heavy and sometimes riding downhill at over 50 mph, these days I rarely get snakebites.

On one occasion when I was new to cycling however, I was riding too close to a car in front of me and when it suddenly swerved I couldn't react quickly enough to avoid hitting a big piece of timber which was lying in the road. Despite having plenty of air in my tyres I got snakebite punctures front and back. After that, I started paying more attention to where I was going (and leaving a sensible gap to the vehicle in front).

I look at the road ahead of me and make a mental note of anything in the distance which might cause problems such as: potholes, raised or missing drain covers, large stones, and pieces of wood or metal. I spot these kinds of things quite often - I just avoid hitting them!

Where I live, it seems to getting quite popular for people to steal drain covers to sell for scrap. Running your tyres at 120 psi isn't going to stop you breaking your neck if you hit an uncovered drain going downhill at 40+ mph.