bike feels squirly - why?

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Hi again, This is going to sound really crazy odd but considering I'm still new to riding a road bike I need to know if this is in my head or is it really happening. I ride my bike on a paved road bike trail - wonderful with no traffic. Well I've only been riding it a few weeks and really getting in to it each time I ride. A couple of nights ago I was on and I noticed when I went round a bend at my usual speed it 'felt' like the bike was sliding out from under me ever so slightly, but enough to make me feel it and feel uneasy. The path was a LITTLE damp from slight rain so I put it down to that and note to self - don't ride in the rain on these tyres I guess?

Well tonight it was NOT raining yet I felt the same uneasy squirly type feeling and now I'm wondering if it's in my head and I'm just losing confidence. I swear it felt real though - almost like I was trying to ride on something like ice (although I know if it were realy ice I would have been off for sure, but you get the idea) I stopped at let some air out the tyres and at first I thought it made some difference but when I went round the bends I felt it again. Surely I can't be imagining something like this? all of a sudden after a few weeks of riding???

The only other thing apart from the tyre pressures (which I had checked before I left the house and according to the pump it said I had 125psi - what the tyres and the LBS say to put in) ......... I live in Florida and it's hot and humid and I'm wondering could it be this ?

Does anyone have any idea if I'm giong mad or is this something that is really happing? I just feel like I'm not gripping the surface as much as I would like, or as much as I had been before. I had not had this sensation up till the other night's ride.

thanks for any suggestions - I don't want to have my confidence knocked now and I don't want to go round corners like some soft girl ( like I did tonight ) ....... I also don't want to wipe out.

:rolleyes:

Hi Kek,

It sounds tyre related.

125psi is quite high, more like the pressure for a heaver male running on 23mm tyres.

Let me know what tyres you are running.

As well as the tyres, what is your weight, I'm 85kg and run mine (Conti GP4000) as low as 85psi in the front. ;)

Might want to check your wheels for lateral movement too. Just try moving the wheel side to side. A little is ok, but if it is enough to hit the brakes could be too much.

thanks for the replies so far. I just checked the numbers on the tyers (being new to all this I'm not quite understanding it all) - it says 700 x 26c .... is that the numbers/size you meant? Also when I was looking for these numbers I did notice that it says "MAXIMUM" psi is 125 - I swear the guy in the shop told me that's what I should have in them.

My weight? umm... somewhere around 150lbs - give or take a few pounds. That would be urghhh : around ?68kg.

thanks for any advice, I'm hoping someone can suggest something before it gets dark tonight 'cause I want to go out. If it doesn't do the usual evening Florida storm thing that is.

:rolleyes:

Try 90 front and 95 rear, see how that goes for a couple of rides. :cool:

Try 90 front and 95 rear, see how that goes for a couple of rides. :cool:I agree with George. 90 front and 95 rear for 26mm tyres with 68kg rider.

At 125psi, the tyre wouldn't of formed the correct contact patch on the ground.

Just wanted to double check. 26mm is an unusual size. Usually they are 23mm, 25mm, 28mm.

thanks for the advice guys. I've been slowly lowering the pressures and right now I have them both about 100psi (because I had not been able to use my computer and not seen your replies) It still feels a bit 'slippery' but not as much at all.
I will try your suggestions on the next ride.

About my 26mm - do you think I'm reading off the wrong numbers? that's all I can see on the tyre. Ie the 700x26

thanks again :rolleyes: from this very new rider

Its like having your back rubbed, sometimes lower is better. :D

nice one mate - I'll keep that in mind ;)

I've just changed over from Maxxis Detonator 700x28C to Continental Gator Skin 700x23C (running 120psi). The Conti's feel much nicer and I can lean over much further without experiencing any vagueness. Skinnier tyre, more pressure, but feels better.

I was getting confused but then thought - wouldn't you automatically have more pressure in a skinnier tyre just because there is less space for that air? Or am I being very female and not getting the physics? That said ...... how the heck are you supposed to know and decide and figure out what pressures you are supposed to have in the tyres? Just by pumping and adjusting and feeling what it's like?

I was getting confused but then thought - wouldn't you automatically have more pressure in a skinnier tyre just because there is less space for that air? Or am I being very female and not getting the physics? That said ...... how the heck are you supposed to know and decide and figure out what pressures you are supposed to have in the tyres? Just by pumping and adjusting and feeling what it's like?Your tyres are 26mm, not 23, and you are much lighter than BB, try the 90/95 we suggested. ;) "Lower, lower, ah, yes, thats better!"

I was getting confused but then thought - wouldn't you automatically have more pressure in a skinnier tyre just because there is less space for that air? Or am I being very female and not getting the physics? That said ...... how the heck are you supposed to know and decide and figure out what pressures you are supposed to have in the tyres? Just by pumping and adjusting and feeling what it's like?If you are putting the same amount of air in a smaller tire (28mm vs 23mm), you are correct the pressure would be greater. However, we are not trying to put in the same amount of air, we usually measure it using the pressure guages on the pumps.

The printed pressures on the sides of the tires say "maximum". Maximum is not necessarily what is best. Usually we run the pressure a little less as it has a softer ride. I personnally run with a 125 psi maximum pressure, 105 front and 110 back when I pump it up. As I check pressure once a week, it is usually down to 85 and 90 by the end of the week. If you are racing, may want to have higher pressures.

You just have to try different methods to see what works best in your situation.

I was getting confused but then thought - wouldn't you automatically have more pressure in a skinnier tyre just because there is less space for that air? Or am I being very female and not getting the physics? That said ...... how the heck are you supposed to know and decide and figure out what pressures you are supposed to have in the tyres? Just by pumping and adjusting and feeling what it's like?I'm yet to see a decent guide on pressure. Mitchelin have one, buts its limited in its info.

Check that there is no play in the head set bearings.Hold the front brake on and rock the bike back and forth.The headset bolts may just have loosened since the bike was assembled.
Everything you ever wanted to know about tyres and tyre pressure... http://www.sheldonbrown.com/tires.html
All About Bicycle Tires and Tubes

you have cured my problem guys - thanks a lot. I went out this morning with the 90 and 95 pressures and no squirlyness at all ..... I went round bends and corners faster, leaned it over and didn't feel anything - it was WONDERFUL. Thanks a lot :)

Check that there is no play in the head set bearings.Hold the front brake on and rock the bike back and forth.The headset bolts may just have loosened since the bike was assembled.
Everything you ever wanted to know about tyres and tyre pressure... http://www.sheldonbrown.com/tires.html
All About Bicycle Tires and TubesSheldonbrown is a wealth of information, but the pressure guide is limited to a single weight, that being 85kg of Bike/Rider. So its good for say a 75kg rider, but doesn't give advice on how to adjust it for other riders.

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