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Discussion Starter · #1 ·
Resident in Aberdeenshire, Scotland, where the temperature has been hovering around 8 C these last few mornings.

Have noticed that the grip in the stock tyres has been seriously compromised at these temperatures.

Lean/speed into corners that wasnt an issue, at mid teens to twenties celsius, now results in front/rear grip loss at 8 C approx.

Covered just over 1000 miles on these tyres, almost no chicken strips.

All my previous bikes with Bridgestone or Pirellis etc. offered no issues even at temperatures hovering around 0 C (unless I as gunning it). These were more powerful bikes too with the usual traction control etc.

Has anyone else experienced lowish temperatures yet & noticed any serious deterioration in grip with the Maxxis?
 

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Doesn't sound good for commuting through London in winter, I may have to get these swapped out sooner than I hoped for some roadtecs or PRs
 

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Discussion Starter · #4 ·
I’ll post some more info if it keeps raising its head.

If it gets really bad, new tyres for me.

For the record, it was completely dry conditions. Coming home in opposite direction, noted no surface gunk etc.
 

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It's winter here and I've been riding in 5 - 12C temps.
I most definitely don't feel secure on the OEM Maxxis tyres, I haven't slid or anything, there just doesn't seem to be any feel in the cold temps and I don't trust them.
I think I will be changing to PR 5's pretty soon.
 

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Looks like I will be having to change those budget OE tyres sooner than I thought, I am picking up my bike next week, and it’s only going to be getting colder.
The budget tyres are one of my main concerns about the bike.
I was considering Metzeler Roadtec 01’s which I found to be a very good allround tyre on my SMT, I know it’s a sports touring tyre but it coped well with everything and excellent in the wet which I get lots of here in west Wales.
 

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Had a slide on the rear tire the other day up here in Norway, around 10 degrees, pushed a bit in a corner, but not too hard, dry road and no debree.

Quite a difference from the BT-021 tyres I had on the SMT, even if those were only sport touring, I felt a lot more confident.

Do not trust these Maxxis to bite very well nearer to 0 degrees.
 

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Problem might not be the tire but pressure in them, all tires need heat to have chemical changes in them that makes them sticky. Usually optimal operating temperature is round 70 degrees if I remember correctly and in cold days if you increased tire pressure you might ride whole day without getting tires warmed up. So what you should try to do is reduce pressure in the tires until you find balance in feedback and grip.

I heard this rule of a thumb on how to quickly set up good starting point for finding optimal tire pressure, I use it with new bike/tire combo. Set pressure to manufacturer spec when cold, remember values and go ride like you normally would, after 15-30 min ( depending on how quickly you would expect tires to warm up) check tire pressure and note that pressure have increased. Good starting point is if your rear tire pressure increases by 15-20% while front increases 10-15%. If your tire pressure didn't rise as much, you need to lower the pressure in them and repeat the process. On the other hand, if your tire pressure increases more then needed you need to increase the pressure in them.

Here is how this works (or better say how tire pressure changes heat generated in them). Low pressure in the tires generates more heat while riding, and vice-versa; high tire pressure = low heat. So while riding tires generate heat and this increases air pressure in them, as pressure rises less heat is being generated. Higher the running tire temperature = more grip tire will have.

This is how I do it, I figure out tire pressure that works well for me regarding the handling (call it preferred tire pressure) and then I try to use as low cold tire pressure I can ride with from cold that will warm up the tire quickly and will get me that preferred pressure when tire is warm. Btw don't be afraid to run tire on low pressure from cold, just don't try racing it on the roads since low tire pressure will give funny feel to the handling. You can also measure tire temperature by hand, ideal temperature is when you can't keep your palm on the tire for more then a second. I always find manufacturers tire pressures to high, specially in the winter.
 

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Problem might not be the tire but pressure in them, all tires need heat to have chemical changes in them that makes them sticky. Usually optimal operating temperature is round 70 degrees if I remember correctly and in cold days if you increased tire pressure you might ride whole day without getting tires warmed up. So what you should try to do is reduce pressure in the tires until you find balance in feedback and grip.

I heard this rule of a thumb on how to quickly set up good starting point for finding optimal tire pressure, I use it with new bike/tire combo. Set pressure to manufacturer spec when cold, remember values and go ride like you normally would, after 15-30 min ( depending on how quickly you would expect tires to warm up) check tire pressure and note that pressure have increased. Good starting point is if your rear tire pressure increases by 15-20% while front increases 10-15%. If your tire pressure didn't rise as much, you need to lower the pressure in them and repeat the process. On the other hand, if your tire pressure increases more then needed you need to increase the pressure in them.

Here is how this works (or better say how tire pressure changes heat generated in them). Low pressure in the tires generates more heat while riding, and vice-versa; high tire pressure = low heat. So while riding tires generate heat and this increases air pressure in them, as pressure rises less heat is being generated. Higher the running tire temperature = more grip tire will have.

This is how I do it, I figure out tire pressure that works well for me regarding the handling (call it preferred tire pressure) and then I try to use as low cold tire pressure I can ride with from cold that will warm up the tire quickly and will get me that preferred pressure when tire is warm. Btw don't be afraid to run tire on low pressure from cold, just don't try racing it on the roads since low tire pressure will give funny feel to the handling. You can also measure tire temperature by hand, ideal temperature is when you can't keep your palm on the tire for more then a second. I always find manufacturers tire pressures to high, specially in the winter.
I agree that Tyre temperature is very important for the tyres to give you the best and different tyre compounds respond to temperatures differently
Tyre pressure requirements are dictated by the construction of the tyre and the load (bike plus rider plus anything else) If one just look at Michelin they have some 20 different motorcycle tyres for road use alone.
SO I WOULD SAY FOR THE INEXPERIENCED STICK TO THE MANUFACTURERS PRESSURES
For others, experiment with care and you can optimize the tyre for you and your machine

Regarding the OEM tyres i find they take a long time to warm up and would agree they are not the best, when mine are worn out i will be changing to Michelin power rs but these are double the price!!!!
 

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I had same problems (as described in this thread) and dangerous skids as beginner rider because no one ever told me this back then. I also noticed some rides had same problem some didn't and I was running new expensive tires and had less grip then some who ran "to the wire" worn tires. I always blamed my tires and I would by new pair and was never happy with them until by accident I came across this tire pressure science and started to experiment with. Today I would say tires are most important safety item on your bike and setting up tire pressure would be among first things one should learn. Experimenting with tire pressure for me was never dangerous, quite the opposite, soon as I started reducing pressure grip started to increase and biggest problem was finding compromise between reduced agility (heavy steering) and grip when tires are cold. It's safe for as long as you make small gradual changes no more then 0.1-0.2 bar per 30-60min test ride.

Grip of any tire is dictated by it's temperature and tire temperature is dictated primarily by ambient/road temperature & tire pressure. What is important to understand is that tire with too high pressure will not generate much heat and it's pressure will not rise much, in other words it will not warm up much above ambient temperature, this means tire will not grip well enough. It is logical conclusion that same tire pressure will not produce same amount of grip at ambient 5 degrees as it would at 25 degrees as already observed & stated in this thread. This is why running manufacturer specified pressures in summer and winter makes no sense.

For those who want to know more google search "Dave Moss" and watch/read as much as you can, not just what he explains about tire pressure, your tire will tell you whats wrong with suspension as well but this is very complicated and requires a lot on track experience.
 

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I cannot believe you managed to get 9000Km, mine rear was dead at 5300Km my front looks like it will last 9000Km so i am expecting the normal 2 rears to 1 front tyre, which is normal for me.
waiting for this pair to go then i will then replace with a set of Michelin Pilot RS
 

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I cannot believe you managed to get 9000Km, mine rear was dead at 5300Km my front looks like it will last 9000Km so i am expecting the normal 2 rears to 1 front tyre, which is normal for me.
waiting for this pair to go then i will then replace with a set of Michelin Pilot RS
Here is a recent pic Of the rear tyre!
 

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These tyres are fine in higher temps well above 10c the carcass feels rock hard rubber is not compliant at anything cold or below 10c. These are a budget tyre regardless and feels like a set of Avon’s I had in 2009. I’ve had the rear step out on me a few times, way more than any other tyre I’ve ever used. Will be switching ASAP
 

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These tyres are fine in higher temps well above 10c the carcass feels rock hard rubber is not compliant at anything cold or below 10c. These are a budget tyre regardless and feels like a set of Avon’s I had in 2009. I’ve had the rear step out on me a few times, way more than any other tyre I’ve ever used. Will be switching ASAP
Rear end pushed out on me early April a couple of times when it was fairly cool here in Nebraska. Replaced them with Michelin PP’s. Seems like they became more and more unpredictable after 2000 miles. I kept them way too long as it was. If I had it to do over, I would have replaced them when I first bought the bike.
 
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