Squared tires

[lizard555]

Hi Guys,

Is there any way to fix squared tires? Can a tire service scrub the edge somehow?

Otherwise I will train figures of 8 until it's good again :-)

Cheers

Safe riding

[Debs]

Ride on more twisty roads. 
The other option is to change them to PR4 GT's 

[markmacd]

I saw a concave inverted file in a shop the other week.

You basically get the bike up on the centre stand and spin the wheel whilst apply light pressure with the file on the corner of the tread.

I tried it on mine and it works a treat. Hopefully get more miles out of me tyres now. 

[ZG]

Ride on more twisty roads. 
The other option is to change them to PR4 GT's 

[virginiajim]

I saw a concave inverted file in a shop the other week.

You basically get the bike up on the centre stand and spin the wheel whilst apply light pressure with the file on the corner of the tread.

I tried it on mine and it works a treat. Hopefully get more miles out of me tyres now. 

I'd like to see a vid of that...

[100milesaway]

Lizard, get yourself over to the Yorkshire Dales, ask for me.   And I'll show how to round off your squares.  It normally takes just one fine weekend. 

[Boomer]

If they are the OEM Bridge then bin them and fit some decent tyres. I rounded off my front BT021 and made it last 7k miles. Wish I'd binned them at 2500 miles.

[lizard555]

Thanks guys! I am actually thinking about PR4 GTs. My rear tyre is BT021 but the front is Bridgestone T30 GT, which should not get the squaring.

[lizard555]

I saw a concave inverted file in a shop the other week.

You basically get the bike up on the centre stand and spin the wheel whilst apply light pressure with the file on the corner of the tread.

I tried it on mine and it works a treat. Hopefully get more miles out of me tyres now. 

Hi, that sounds interesting. Could you please post a photo or name of its manufacturer? Is it a DIY solution or a motorcycle solution? Sorry, new to this completely. I actually hate the fact that the tires are expensive, do not last, slip, get squared which leads me to fear of cornering.

[virginiajim]

You can still corner, just makes a bit of noise.

[lizard555]

So I looked again on the Michelins PR4 GTs and decided to purchase them. I still have a question - I am afraid of cornering on wet surface. I am afraid I will get a skid and fall. What is your experience with skidding on a wet surface? Would you for example corner cautiously or you do not think about it at all? I am quite afraid whenever the angle needs to be bigger - this is on wet surface. I was told also that the squared tyres do not help the confidence, as there is the edge. Do these tyres help on the wet surface during cornering? I read they have a softer surface on the sides to help cornering. Would you use some technique how to recognize the grip during current conditions when you ride?

[BigAlan]

I have had the PR4 tyres now twice on my GTR and will go again later this year, i have found even in the really wet i can be stable all the time, even on a smooth wet surface in Germany last year with diesel on the roundabout they not only gripped but when i lost traction opening the throttle to much the traction control kicked in and worked a treat.

Overall i can say I never manage to get the PR4 tyres to let go, ok i dont ride likea GP rider but when "up norf" with 100milesaway and OC who ride at a good pace all over the place i manage to keep up, so have no worries about the PR4 tyre.

Alan

[Winston Smith]

So I looked again on the Michelins PR4 GTs and decided to purchase them. I still have a question - I am afraid of cornering on wet surface. I am afraid I will get a skid and fall. What is your experience with skidding on a wet surface? Would you for example corner cautiously or you do not think about it at all? I am quite afraid whenever the angle needs to be bigger - this is on wet surface. I was told also that the squared tyres do not help the confidence, as there is the edge. Do these tyres help on the wet surface during cornering? I read they have a softer surface on the sides to help cornering. Would you use some technique how to recognize the grip during current conditions when you ride?

The only real issue is your in your head. 

Modern tyres will grip almost as well in the wet as in the dry, all you need is confidence in them.

Best way to start to gain that confidence is to understand the physics.

Tyres have a tread pattern built into them.  Daft as it is, the tread pattern isn't what creates the grip.  Grip comes from the rubber compound gripping the road surface.  The tread pattern is designed to allow the rubber bits to do their job in wet conditions.

What they do is channel the water away.  As the solid rubber hits the water it would fail to adhere to the road as it would be a barrier (aquaplaning).  The water is squeezed into the tread grooves and as this occurs the rubber then grips onto the surface.  The edges of the tread effectively 'cut' through the water.





Tyres such as the PR series 3 & 4 have sipes in them.  These are very fine grooves which feed the water out of the main tread so water doesn't get the opportunity when it's torrential to build up.  The bonus of this is that it clear normal water more effectively, stops the water cooling the tyre, and gives a better feedback and grip.  This is one of the reasons the PR's feel better in the wet.  It's the same technology used on winter tyres for cars to disperse the water before it re-freezes.

Now about that head?!

Trust the tyres that they're doing their thing!

When riding in the wet make a conscious effort to relax.  Drop your shoulders. Let your elbows flex.  Gentle grip on the handlebar grips, think holding a bird type level of grip (I mean sparrow btw?!).

Make sure you get your speed down in a straight line before entering the bend/corner/hazard.

Use all three brakes. 
Throttle off (engine brake).
Rear brake and front brake at 50/50%, again gently and not harshly.
Take the appropriate gear, bring revs up to match the road speed (blip or hold throttle slight open as you let the clutch out). Consider a gear higher than you normally would use as the idea is not to lose traction.  Too low a gear make cause wheel spin.

As you take the hazard remain relaxed and drop the leading shoulder/elbow into it.
This will help balance the bike, keeping it slightly more upright.
Keep throttle feathered/slightly open through the hazard as this will generate grip using the torque, breaking the surface of the water allowing the tyres to work.

Best way to learn is to get out when it's raining and practice when you have no time constraints (i.e. not going to work when it starts raining).

Three point advice is understand what the tyres are doing, relax and be gentle with the controls.

T.R.UST. - Tyres - Relax - Use Suitable Traction

[lizard555]

thanks you guys, you are very helpful

[Ant]

Chris,
One thing I've never understood though is the direction of the sipes on the front tyre of a PR4. Its as though they squirt the water inwards !