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View Full Version : Tyre pressures? Yes I know it's been done to death



v8s&2wheels
29th April 2010, 17:12
Just tested my tyres today (cold) since its been a good couple of months since i checked them and inflated.

Front was 29.5 and rear was 27. I noticed and felt the rear has been a bit low. But is this dangerously low or bad at all for the tyre?

Obviously im going to go pump them up. Since tyres will be warm thinking 36 front and 40 rear.

Should probably say this is on my gsxr1000k7 with 120/70 and 190/50 with pilot road 2's.

I know all about the 3 degrees from cold to hot but not really too interest if im only 2.5-3.5 degrees warming up.

Should also mention bike is used mainly for going to work and little rides by myself. But also starting to ride 2 up on little rides maybe once a week. So trying to get a good compromise on tyre pressures for single and 2 up riding.. without having to change pressures for each type of ride.

Perhaps 38/42 warm pressures? Whats your views on all this.

Cheers
Anyone have any recommendations for what sort of pressures i should stick around.

YellowDog
29th April 2010, 17:20
Published tyre ratings are based upon what the manufacturer's lawyers tell them to quote.

My PR2s state 42 Rear and 34 Front. After a lot of testing I find that 39 Rear and 34 Front suits me best.

If you run with too low pressure you will get excessive wear.

Cornering's not too much fun either :)

MSTRS
29th April 2010, 17:25
Different tyres 'like' different pressures, too.
I'm running PR2s at 38/35. Last set I ran at 37/33, but the front was getting very triangulated. After 17,000kms. So, knowing that firmer lasts longer...

v8s&2wheels
29th April 2010, 17:27
Different tyres 'like' different pressures, too.
I'm running PR2s at 38/35. Last set I ran at 37/33, but the front was getting very triangulated. After 17,000kms. So, knowing that firmer lasts longer...

Is that 38 rear 35 front? Yeah might just go with 36 front 42 rear warm pressures since theres going to be 2 up involved.. the higher pressure in the rear should help

The Stranger
29th April 2010, 17:48
Front was 29.5 and rear was 27. I noticed and felt the rear has been a bit low. But is this dangerously low or bad at all for the tyre?



What works for you on your bike?
I ran 33 front and 27 rear (too hard I know, but was going to take SH1) on the weekend.
SH22 was too appealing in the end but rear was slipping and sliding. Dropped a couple of pound out and the rear came right, wasn't until a dropped a couple on the front though that it all came together.

MSTRS
29th April 2010, 18:17
Is that 38 rear 35 front? Yeah might just go with 36 front 42 rear warm pressures since theres going to be 2 up involved.. the higher pressure in the rear should help

Rear should always be a bit harder than the front. I know 'they' say you should, but I never bother upping for pillion...don't have any issues.

sil3nt
29th April 2010, 18:47
This is obviously going to vary a lot but how much pressure is gained through heat? Are we talking 1 or 2 PSI or a bit more?

Mudfart
29th April 2010, 19:12
holy shit, a couple of months? I check mine all the time, on my 250!. at least check em every second gas fill.

jtzzr
29th April 2010, 19:35
Different tyres 'like' different pressures, too.
I'm running PR2s at 38/35. Last set I ran at 37/33, but the front was getting very triangulated. After 17,000kms. So, knowing that firmer lasts longer...

I had a front changed and it was somewhat triangular, so I asked the guy why that was and he said it was because i had over-inflated the tyre , but his boss said that was`nt the reason, he said it was because of the camber on the road , which makes sense I suppose so the right hand side of the tyre wears more.

Oh I run 42 front and rear on Pilot powers , factory recommendation.

cheshirecat
29th April 2010, 20:08
Running Conti road attacks - 2nd set and now using 42 rear as per spec and 39 front (spec is 36). Find it sensitive, a couple of psi either way makes a big diference but the higher front presure helps roll in and wear especially mid life. This is on an elderly VFR. If the rear drops to mid 30's it's all over the place! I check tyres every fill up or at least two days.

pritch
29th April 2010, 20:34
My Honda manuals said 36 F, 42 R. So that was mostly what I did, unless there was a reason to do something different.

The Ducati metric figures convert to about 31 and 32psi which I found a bit startling. There is however a warning that at these pressures you can damage your nice rims if you ride on rough roads, and we definitely do have rough roads. So I'm running 34 and 36. These lower pressures will probably reward more regular checks.

peasea
29th April 2010, 21:14
Just tested my tyres today (cold) since its been a good couple of months since i checked them .

Ya fuckin' what??
If I haven't checked my tyres come Sunday evening I get paranoid.

I ride every day most weeks, five for work and at least one for rec'. Fucksake. Seriously; I check my tyres more often than my oil level. The only thing I do more often is clean my visor.

Kuppla months? Come on, with the varying temperatures in NZ it should be at least fortnightly, if not weekly like my good (saintly) self.

Unless you've filled your tyres with nitrogen I guess.

v8s&2wheels
29th April 2010, 22:21
Ya fuckin' what??
If I haven't checked my tyres come Sunday evening I get paranoid.

I ride every day most weeks, five for work and at least one for rec'. Fucksake. Seriously; I check my tyres more often than my oil level. The only thing I do more often is clean my visor.

Kuppla months? Come on, with the varying temperatures in NZ it should be at least fortnightly, if not weekly like my good (saintly) self.

Unless you've filled your tyres with nitrogen I guess.

Yeah ive been really slack lately eh.

Ive only been getting on it maybe twice a week at the moment - sometimes 3 times a week. Normally every time i fill her up i pull out my tyre gauge and do the business on the tyres while im at the servo. Only filled up maybe 3 times in the last 2 months, but each time its been in a rush just to get the gas and get to where i need to be.

Just noticed about 2 weeks ago the rear was feeling too soft and especially with the pillion on. But have only ridden it 2 times since then.

Had a day off today so got a lot of things done i needed and then sparked in my head i should check my tyres, thats when the shock came.

Anyways tyres are still low as didnt get a chance to leave the house today. So will ride to work tomorrow and fill it up and do the tyres at lunch time.

Used to pump the tyres upto 36 front and 39 rear when stopped at gas station (warm tyres) and that really worked a treat. So might just add a couple psi to the rear for the passenger since she rides a bit now.

onearmedbandit
29th April 2010, 23:20
I check mine every ride. But then I am running dunlop ntec's that run 34 front and 24 rear. Very very sticky tyres but lose pressure quickly, hence the regular checking. But even when I'm running 'normal' tyres like PP's or similar I check them before every ride. Amazing the difference 1-2psi can make to the way the bike feels.

peasea
30th April 2010, 06:33
I check mine every ride. But then I am running dunlop ntec's that run 34 front and 24 rear. Very very sticky tyres but lose pressure quickly, hence the regular checking. But even when I'm running 'normal' tyres like PP's or similar I check them before every ride. Amazing the difference 1-2psi can make to the way the bike feels.

Have you looked into nitrogen? Talk to your tyre shop, it holds the pressure for ages.

onearmedbandit
30th April 2010, 08:41
Have you looked into nitrogen? Talk to your tyre shop, it holds the pressure for ages.

Might give it a whirl, but I think there's only a couple of places in town that supply it. Thanks.

imdying
30th April 2010, 09:00
Might give it a whirl, but I think there's only a couple of places in town that supply it. Thanks.Phil has a bottle and a filler, we use it on the mini motos (because taking a compressor to a car park would be futile).

Muppet
30th April 2010, 09:37
Recommended pressures for my bike are 41 front and rear. Seems a bit high compared to other sportbikes, but other sportbikes don't weight 215 kg dry either!! I have put 36 front and 38 rear. I have found the softer pressures seem to soak up the small road imperfections and also the ripples on corners caused by trucks which are going to be allowed to carry an exta 9 tonnes per truck! But that's for another day........Having owned an R1 not too disimilar from your Gixxer I'd be putting a sport tyre on the front at 34-36 and a sport touring tyre on the rear at 38 myself. NZ roads are made of that coarse chip that gives loads of grip. You don't need race rubber. My two cents worth.

Conquiztador
30th April 2010, 20:23
"I had a front changed and it was somewhat triangular, so I asked the guy why that was and he said it was because i had over-inflated the tyre , but his boss said that was`nt the reason, he said it was because of the camber on the road , which makes sense I suppose so the right hand side of the tyre wears more."

Yep, so true. Have look at these pics. Was confused first how right side could have so much more wear. But after some brain work we came to same conclusion

Muppet
30th April 2010, 22:55
"I had a front changed and it was somewhat triangular, so I asked the guy why that was and he said it was because i had over-inflated the tyre , but his boss said that was`nt the reason, he said it was because of the camber on the road , which makes sense I suppose so the right hand side of the tyre wears more."

Yep, so true. Have look at these pics. Was confused first how right side could have so much more wear. But after some brain work we came to same conclusion

That's quite fascinating. Is the roads' camber quite pronounced where you llive? You'd also be leaning in to the right side without realising it too.

scracha
1st May 2010, 08:55
Yep, so true. Have look at these pics. Was confused first how right side could have so much more wear. But after some brain work we came to same conclusion
Bent frame or swingarm :-)



Check pressures.....hell, about every 6 months if she feels a bit skittish?

Conquiztador
1st May 2010, 09:32
Bent frame or swingarm :-)

Check pressures.....hell, about every 6 months if she feels a bit skittish?


No, all straight, wheels in line, bearings good and pressure fine. Bike used mainly to and from work with some minor rides occasional w/e. So the tyres go over same road every day, also through 3 roundabouts a day x 2.

Bad Gixxer
1st May 2010, 15:26
Just tested my tyres today (cold) since its been a good couple of months since i checked them and inflated.

Front was 29.5 and rear was 27. I noticed and felt the rear has been a bit low. But is this dangerously low or bad at all for the tyre?

Obviously im going to go pump them up. Since tyres will be warm thinking 36 front and 40 rear.

Should probably say this is on my gsxr1000k7 with 120/70 and 190/50 with pilot road 2's.

I know all about the 3 degrees from cold to hot but not really too interest if im only 2.5-3.5 degrees warming up.

Should also mention bike is used mainly for going to work and little rides by myself. But also starting to ride 2 up on little rides maybe once a week. So trying to get a good compromise on tyre pressures for single and 2 up riding.. without having to change pressures for each type of ride.

Perhaps 38/42 warm pressures? Whats your views on all this.

Cheers
Anyone have any recommendations for what sort of pressures i should stick around.

I've got a K7 GSXR1000 as well, running Bridgestone BT016. I've mucked around with pressures quite a bit both on the track and on the road. For me (78kg plus leathers) I've found that the track likes 32/36 cold and that suits my riding style, gets a bigger footprint on the ground under braking but still corners well and doesn't shag the shoulders too much, even thoiugh 016's are prone to front shoulders taking a hammering.

On the road riding single I've tried all psorts of pressures and and I reckon that 34/40 is probably about the best. I was running 32/38 but found the front wore too fast although it felt OK.

As for pillion riding, I'd say stick to the Suzuki recommendation at 36/42 and dick around with your suspension rather than the tyre presssure to get a more comfortable or better handling ride.

v8s&2wheels
2nd May 2010, 20:08
I've got a K7 GSXR1000 as well, running Bridgestone BT016. I've mucked around with pressures quite a bit both on the track and on the road. For me (78kg plus leathers) I've found that the track likes 32/36 cold and that suits my riding style, gets a bigger footprint on the ground under braking but still corners well and doesn't shag the shoulders too much, even thoiugh 016's are prone to front shoulders taking a hammering.

On the road riding single I've tried all psorts of pressures and and I reckon that 34/40 is probably about the best. I was running 32/38 but found the front wore too fast although it felt OK.

As for pillion riding, I'd say stick to the Suzuki recommendation at 36/42 and dick around with your suspension rather than the tyre presssure to get a more comfortable or better handling ride.

I adjusted the suspension when i first started riding 2 up as current set up was really soft and horrible. Front is back to factory specs and rear is a bit stiffer than factory now.

Just got around to doing my tyres after work today ended up putting in 36 front and 40 rear (yet to check with my tyre gauge what it actually is). And This is the nicest my bike has ever handled riding by myself. So im definately sticking with around these pressures. Ill hopefully go out for a ride 2 up in the next 2 or 3 days and then judge if maybe i need a couple more pounds in the rear tyre.