Probably a topic beaten to death...
Discussion
...not 954RR, which is one of the best bikes ever!
...but if you have more jokes - let's hear them!
Anyway, it's about tyre pressure you use on your road bikes.
Why I ask is because last time I was taking a right corner hanging off of my 600 Honda with maybe 55nm torque at 12500rpm (and I was at half that rpm at best) and I did not hamfisted the throttle but I felt the rear stepping out momentarily, which is a butt-clenching feeling to say the least.
It was a warm (15C+) day and dry, the tarmac in the corner is pretty smooth I would say, not the track-level grip for sure.
I have Metzeler M7RR rubber on the bike.
I do not use the typical 2.5bar front 2.9bar rear suggestion of Honda, I do 2.30-2.35 front and 2.6-2.7 rear.
BTW, reading the Triumph Daytona manual the suggested pressures are 2.35 and 2.48 bars.
Out of curiosity, what tire pressures do you use for road riding with a gusto (and I do not mean straight line blasts, but rather corners/hairpins)?
I was at an event yesterday and got the chance to ride 2027 RSV4RF and Tuono 1100RR.
Damn nice bikes!
The RSV4 is high and the seat is a plank, and the engine sounds like a bucket of bolts at below 4000rpm.
Also it's a bit jerky on 1-2 and 2-1 quickshifter shifts (I also caught a neutral doing 2-1 once, but that happens on all bikes with blippers).
Otherwise - fantastic machine. No need to mention the heavenly handling.
What I found is that RSV4RF is easy to ride, great mirrors, did not get hot on the legs or bum, started on the button even on hot engine, also engine cooling works really well.
The noise is great, but it kind of disappears inside the helmet once you go at 60-70mph, replaced by wind noise, but it could have been wind screen blowing it onto my head, because on Tuono the engine/exhaust noise is more noticeable, it is always present. Also, Tuono has much softer seat and the suspension is more plush, unlike Ohlins on RSV4. Tuono is freaking awesome!
I did not ride these things on the hairpins, just on countryside roads, some bends, some straight line blasts...I was riding them and thinking how wasted they are in these settings, you cannot use the engine properly without risking jail, this concerns RSV4 in particular, this bike is totally underused on public roads. I got lucky and did not get a speeding fine because oncoming car drivers warned me about hidden camera, it was a couple of police cars hiding behind trees with a police guy with a speed gun standing behind a tree.
Anyway it was a nice day, and yes, I am keeping the 954.
Some people even tried this masochism:
Could not get a ride on either Street Triple RS or R1, too long queues to wait, I will find RS in local dealership and I am riding R1 on a race track in Italy in the summer.
On the parking lot I saw this rare beauty:
...but if you have more jokes - let's hear them!
Anyway, it's about tyre pressure you use on your road bikes.
Why I ask is because last time I was taking a right corner hanging off of my 600 Honda with maybe 55nm torque at 12500rpm (and I was at half that rpm at best) and I did not hamfisted the throttle but I felt the rear stepping out momentarily, which is a butt-clenching feeling to say the least.
It was a warm (15C+) day and dry, the tarmac in the corner is pretty smooth I would say, not the track-level grip for sure.
I have Metzeler M7RR rubber on the bike.
I do not use the typical 2.5bar front 2.9bar rear suggestion of Honda, I do 2.30-2.35 front and 2.6-2.7 rear.
BTW, reading the Triumph Daytona manual the suggested pressures are 2.35 and 2.48 bars.
Out of curiosity, what tire pressures do you use for road riding with a gusto (and I do not mean straight line blasts, but rather corners/hairpins)?
I was at an event yesterday and got the chance to ride 2027 RSV4RF and Tuono 1100RR.
Damn nice bikes!
The RSV4 is high and the seat is a plank, and the engine sounds like a bucket of bolts at below 4000rpm.
Also it's a bit jerky on 1-2 and 2-1 quickshifter shifts (I also caught a neutral doing 2-1 once, but that happens on all bikes with blippers).
Otherwise - fantastic machine. No need to mention the heavenly handling.
What I found is that RSV4RF is easy to ride, great mirrors, did not get hot on the legs or bum, started on the button even on hot engine, also engine cooling works really well.
The noise is great, but it kind of disappears inside the helmet once you go at 60-70mph, replaced by wind noise, but it could have been wind screen blowing it onto my head, because on Tuono the engine/exhaust noise is more noticeable, it is always present. Also, Tuono has much softer seat and the suspension is more plush, unlike Ohlins on RSV4. Tuono is freaking awesome!
I did not ride these things on the hairpins, just on countryside roads, some bends, some straight line blasts...I was riding them and thinking how wasted they are in these settings, you cannot use the engine properly without risking jail, this concerns RSV4 in particular, this bike is totally underused on public roads. I got lucky and did not get a speeding fine because oncoming car drivers warned me about hidden camera, it was a couple of police cars hiding behind trees with a police guy with a speed gun standing behind a tree.
Anyway it was a nice day, and yes, I am keeping the 954.
Some people even tried this masochism:
Could not get a ride on either Street Triple RS or R1, too long queues to wait, I will find RS in local dealership and I am riding R1 on a race track in Italy in the summer.
On the parking lot I saw this rare beauty:
sjtscott said:
Tyre pressures are very personal and also can be bike specific. For my two hondas (CBR600F and Blackbird) I ran OE/Book pressures front and rear. The blackbird in particular any deviation of these less or more esp on the front really affected how it handled. It didn't feel right with even two psi down on the front.
For my current speed triple I'm currently running a little more pressure on the front and a little less than triumph state in the book.
I had the rear stepping out on my 2002 CBR600F4i. For my current speed triple I'm currently running a little more pressure on the front and a little less than triumph state in the book.
I already have 2.7 cold rear, but seems this is too high as well when the surface is dry and sun-lit and ambient temp is 15C+.
The tires do warm up even from casual riding and I measured the rear to 2.9 warm, I think that's too high.
cbmotorsport said:
Pretty much always used manufacturer recommendations for tyre pressures, usually 36F 42R. Never really felt a need to change, unless on track. I did drop them in the Alps, when it was 35c and very good tarmac, but for general spirited riding, i don't bother.
I will say that momentary losses of traction are pretty common, and usually for no apparent reason. Sometimes it's obvious - gravel/diesel etc, but sometimes it just happens. I wouldn't start messing round with tyre pressures that obviously work for you 99.999% of the time, just because you've had a little 'moment'.
But 2.9 cold on the rear quickly turns into 3.2 warm and leaned over on not track-level-grippy asphalt (even more polished in hard corners than on straight parts) I think this pressure is just too much, the tire is too hard to grip. I was not 50-degrees leaning and was not in high rpm and opened throttle only slightly (was going uphill) and the rear twitched. It's not a nice "moment". I will say that momentary losses of traction are pretty common, and usually for no apparent reason. Sometimes it's obvious - gravel/diesel etc, but sometimes it just happens. I wouldn't start messing round with tyre pressures that obviously work for you 99.999% of the time, just because you've had a little 'moment'.
With higher pressure the front steers quicker, that's very noticeable, but that also means the grip is not the same as the contact patch is smaller.
Loyly said:
I use the book pressures for my Daytona. That said, I have ridden with the pressures slightly under the book recommendations. I notice that when the pressures are down just a little bit, the bike feels slower to turn in.
I know some lads reckon on different pressure settings for the T595 Daytona, but I haven't really investigated any different settings. I can recall one user here saying he really sharpened his Daytona's handling with slightly higher pressures but that post is lost to time now.
I also use book pressures for Daytona, 2.35 and 2.48, they seem spot-on, especially for soft tire like Supercorsa that come stock on this bike.I know some lads reckon on different pressure settings for the T595 Daytona, but I haven't really investigated any different settings. I can recall one user here saying he really sharpened his Daytona's handling with slightly higher pressures but that post is lost to time now.
For Ducati Monster 696 the recommended tire pressures are even lower, 2.1 bar front and 2.2 bar rear, if I remember correctly.
If you look at any Japanese bike - the recommended pressures are always 2.5 bar front and 2.9 bar rear, that's cold pressures! I think these recommendations are from 20 years ago or something, they just don't feel right (unless you are two-up on a highway).
MattOz said:
Tyre pressures.
I use 33psi front and 35psi rear, so what's that, 2.3 and 2.4 bar respectively. That's on my K7 GSXR1000, using Supercorsa SP's.
I have to try this on my K6. I use 33psi front and 35psi rear, so what's that, 2.3 and 2.4 bar respectively. That's on my K7 GSXR1000, using Supercorsa SP's.
I have Racetec K3 RR on it now, switched from SC SP as those wear too damn fast (especially front sides, as I ride K6 only on uphill-downhill hairpins).
I have 2.3 front and 2.6 rear, cold.
julian64 said:
2.38-2.45 bar.
Can I just say I love your enthusiasm.
The above figure equate to 34.986 psi to 36.015 psi. You are specifying the pressure down to 0.15 psi.
Now I don't know what you are using to fill the tyres on your bike, but the compressor I use would be pretty chuffed if it could specify a pressure within 5psi, and that's before the heat of riding mucks about with it another 5-10 psi
So I tend to run my bike at 30psi cos its the big figure on the very small dial I use, and check the rims aren't touching the ground when I sit on the bike. Then I'm good to go.
Thank you! Can I just say I love your enthusiasm.
The above figure equate to 34.986 psi to 36.015 psi. You are specifying the pressure down to 0.15 psi.
Now I don't know what you are using to fill the tyres on your bike, but the compressor I use would be pretty chuffed if it could specify a pressure within 5psi, and that's before the heat of riding mucks about with it another 5-10 psi
So I tend to run my bike at 30psi cos its the big figure on the very small dial I use, and check the rims aren't touching the ground when I sit on the bike. Then I'm good to go.
Yes, that is why I have a digital pressure gauge (Oxford Air Gauge, I bought it because it got top marks in a test of 10 gauges) and a Michelin pump with a digital gauge. I always use both and they are within 0.2 bar off each other....and both could be wrong, so maybe I need a third gauge, which is known to be precise!
Oh, I do not measure by psi, I measure by bar.
scorcher said:
33F and 34R on my KTM 950 using Michelin Pilot Power 2CT's. Drop them to 32/32 when its really warm. I always thought 36/42 seemed too hard. Usually best just to drop a couple of PSI out at a time and see how it feels. You can always put them back up again if it doesn't suit!
Exactly!I think I will drop to 2.2 front and 2.4 rear, cold, see how that feels.
cmaguire said:
cbmotorsport said:
Well, you evidently know more than all those boffins that design motorcycles and tyres and spend hundreds of millions of pounds in R&D. :-)
The manufacturer settings are a catch-all though, based around the tyres they supply the bike with and that you might ride with a pillion or be fat etc36F 42R is mostly manufacturer default.
I just go with 33/34F and 38R as a start on the road.
Checking the rear after riding on some decent roads in Spain that 38 had become 44. I have M7RR on the GSXR and they occasional step a little on the back (No heroics going on in my book) but I get the same with the PR4 on the Street Triple. A friend I ride with of similar speed never seems to have a problem, even though he leans a little more than me. My suspicion is that my style of riding with my balls on the tank, as opposed to his where he sits further back in the seat, might have something to do with it as he has more weight on the rear.
.
Exactly! And in the summer the tires get really hot, so 44 is pretty normal then. That's why Triumph recommends 2.35 and 2.48 on SC for the street, I bet!
I also tend to slide forward a lot. Really, I have to work on my posture on the bike...
Birky_41 said:
MattOz said:
Tyre pressures.
I use 33psi front and 35psi rear, so what's that, 2.3 and 2.4 bar respectively. That's on my K7 GSXR1000, using Supercorsa SP's.
This ^^ I run maybe 1psi more on front not that I could really tell (probably in my head) with M7RR's and 34/35 rearI use 33psi front and 35psi rear, so what's that, 2.3 and 2.4 bar respectively. That's on my K7 GSXR1000, using Supercorsa SP's.
Dont overthink it. Just bung that in them cold, go out and ride. You'll be fine.
Unless you are on the 954 in which case you can run anything as that handles like a Aprilia RS250
Besides, like mentioned above, the gauges all show different values, who knows what the true pressure is, one has to test oneself forward.
954
But I liked the new GSXR1000 and the RSV4RF left a great impression as well.
Fireblade SP was great as well, I guess I just have too many Hondas to spare some love for another one. The underdog Gixxer is more my bike.
Loyly said:
moanthebairns said:
36 F 36 R cold, I'm doing it all wrong. Anyone who measures tyre pressure in bar is just weird.
HO LEE KAU is in Switzerland IIRC so maybe they do it differently there. My pump and gauge are pretty accurate (I use a foot pump and an electronic gauge, which tally very closely when measured). But, it sounds as though I'm overthinking my pressures a bit much. I always thought that they were critical since you rely on such a small contact patch on a bike. I'm glad to see some more relaxed attitudes to this.
Farlig said:
julian64 said:
2.38-2.45 bar.
Can I just say I love your enthusiasm.
The above figure equate to 34.986 psi to 36.015 psi. You are specifying the pressure down to 0.15 psi.
Ehh no, not quite; you´re taking what is an already higher resolution measurement of pressure & quoting it to three decimal places.Can I just say I love your enthusiasm.
The above figure equate to 34.986 psi to 36.015 psi. You are specifying the pressure down to 0.15 psi.
When measuring in bar, if you quote only one decimal place the resolution is not fine enough.
ie going from 2.3 to 2.4 bar is the same as going from 33.4 psi to 34.8 psi or rounded 33 to 35 psi, certainly sufficient to make a difference.
So measuring in bar, one must quote 2 decimal places to achieve a sensible resolution, whereas measuring in psi, there´s no need to use more than one decimal place, if that.
(Oh & your conversion factor is wrong... 1 bar = 14.5038 psi => 2.38 bar = 34.519 psi & 2.45 bar = 35.534 psi)
tight5 said:
Ho Lee Kau said:
I felt the rear stepping out momentarily
It was a warm (15C+) day and dry
Were your tyres up to temprature ?It was a warm (15C+) day and dry
Cold tyres don't work too well !!
Pressures from the manual for me.
Tango13 said:
O/P, Just how knackered is your suspension?
Last Sunday I was out in similar conditions running 36f/42r with 80 lbs/ft or 110nm of torque from 4,000rpm to 9,700rpm and I had zero problems with grip. Even in much cooler conditions the rear has only ever let go once and that was more of a gentle drift than a 'slip'
This is a 2002 bike, but 2 years ago I ordered a new WP shock with hight adjustment and replaced the components in the shock with Race Tech components (springs, valves + oil), I lifted the bike about 20mm front and rear. The suspension parts + work cost me more than the bike (that's how much I like this old bird)! Last Sunday I was out in similar conditions running 36f/42r with 80 lbs/ft or 110nm of torque from 4,000rpm to 9,700rpm and I had zero problems with grip. Even in much cooler conditions the rear has only ever let go once and that was more of a gentle drift than a 'slip'
In other words, the suspension is fresh.
King Herald said:
julian64 said:
2.38-2.45 bar.
So I tend to run my bike at 30psi cos its the big figure on the very small dial I use, and check the rims aren't touching the ground when I sit on the bike. Then I'm good to go.
I love the way some people bandy around tiny fractions of a bar, like it is some surgical procedure and they are filling their tyres with nitrogen, in a climate controlled sterile zone, to be used on an indoor air con racing track. So I tend to run my bike at 30psi cos its the big figure on the very small dial I use, and check the rims aren't touching the ground when I sit on the bike. Then I'm good to go.
Tell this to TRIUMPH!
(That's in their manual, you know.)
julian64 said:
Farlig said:
julian64 said:
2.38-2.45 bar.
Can I just say I love your enthusiasm.
The above figure equate to 34.986 psi to 36.015 psi. You are specifying the pressure down to 0.15 psi.
Ehh no, not quite; you´re taking what is an already higher resolution measurement of pressure & quoting it to three decimal places.Can I just say I love your enthusiasm.
The above figure equate to 34.986 psi to 36.015 psi. You are specifying the pressure down to 0.15 psi.
When measuring in bar, if you quote only one decimal place the resolution is not fine enough.
ie going from 2.3 to 2.4 bar is the same as going from 33.4 psi to 34.8 psi or rounded 33 to 35 psi, certainly sufficient to make a difference.
So measuring in bar, one must quote 2 decimal places to achieve a sensible resolution, whereas measuring in psi, there´s no need to use more than one decimal place, if that.
(Oh & your conversion factor is wrong... 1 bar = 14.5038 psi => 2.38 bar = 34.519 psi & 2.45 bar = 35.534 psi)
You on the other hand come to correct my maths down to one ten thousandth of a psi when your foot pump could probably only be 'accurate' to 2-3psi despite the 'precision' on your gauge.
And that completely bypasses the question of whether one of you could actually tell the difference in riding with a change of 5psi which I would be willing to bet none of you could in any sort of blind trial.
So ........whhhhhoooooshhhhhhh
Still, tire pressure is an important topic, and 0.1 bar could mean a lot.
moanthebairns said:
tight5 said:
Ho Lee Kau said:
I felt the rear stepping out momentarily
It was a warm (15C+) day and dry
Were your tyres up to temprature ?It was a warm (15C+) day and dry
Cold tyres don't work too well !!
Pressures from the manual for me.
I mean I've had a near enough high side in the rain on s
t tyres, on greasy roads, cold tyres, fked tyres and on the track....And all of these were rider error (too much throttle/lean asking too much etc), or/and cold tyres.
Would a few psi cause "stepping out". How bad a stepping out are we talking here, out your seat, balls off the tank, buy a lottery ticket or the bike telling your "WARNING, WARNING, I'm getting pretty fed up being a motorbike, I'm just letting you know I'm thinking about turning myself into a scud missile if you keep ham fistedly applying that throttle you clown".
The stepping out, well, I felt it and it was not a good feeling, I am very fond of my body as well as my bike (even though it is old and used and beaten up and I dropped it already 2 times).
I decreased the pressures yesterday and went for a ride, it felt better, but, of course, I am not Rossi/Marquez/Crushlow, I cannot tell with minute precision if things are better or worse, plus I am not pushing to the limit.
I still think it an important and interesting question, the tire pressure, and I am collecting information from everyone here to make an educated guess.
308mate said:
moanthebairns said:
tight5 said:
Ho Lee Kau said:
I felt the rear stepping out momentarily
It was a warm (15C+) day and dry
Were your tyres up to temprature ?It was a warm (15C+) day and dry
Cold tyres don't work too well !!
Pressures from the manual for me.
I mean I've had a near enough high side in the rain on s
t tyres, on greasy roads, cold tyres, fked tyres and on the track....And all of these were rider error (too much throttle/lean asking too much etc), or/and cold tyres.
Would a few psi cause "stepping out". How bad a stepping out are we talking here, out your seat, balls off the tank, buy a lottery ticket or the bike telling your "WARNING, WARNING, I'm getting pretty fed up being a motorbike, I'm just letting you know I'm thinking about turning myself into a scud missile if you keep ham fistedly applying that throttle you clown".
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