Tyre pressure probs- What tyre pressure do you prefer?

Hi guys,
Well I'm quite new to biking having only passed my test a couple of months ago so up to now, due to snow and ice,I've only done about 300 miles on my cb500.

I,m finding that each time I go out my rear tyre has lost tyre pressure.Its affecting the handling and me getting used to the bike. I had it into a bike repair shop last week......just taken it out again yesterday for a ride and tyre pressure slightly down again yesterday.... only 24psi after about 1week.
It is irritating as it means every trip i do so far starts with a trip to the garage to get it pumped up.


I have set them so far at front 29psi/ rear 36psi

Any ideas anyone or do i need to buy a new tyre? plenty of tread left on the one i have so I'm reluctant too.
Anyone had similar probs? Anyone prefer different pressure than the reccomended?

Cheers

possible cause of the rear tyre loosing pressure

1-- possible nail in tread?

2-- possible leak at tubeless valve or valve core

3-- possible leak around the rim caused by build up of corrosion between tyre and rim.

4-- very unlikely possible porous alloy wheel (has been known to happen though)

i would take the wheel of and put it in a bath to find out where it is leaking from or lye the wheel flat and pour water (with a little washing up liquid)round the rim and look for the bubbles

hope this helps

I've had a good look at tyre re any nails or anything and can't see anything. I have also tighened the shrader valves and put new caps on. I do tend to think it must be the rim or 'tyre beading' of the tyre..I was considering increasing the pressure to see if it seals it better..it may well have been run at a higher pressure in the past or something..what pressure do you set yours at?

Like you say it may be a case of getting under water or wasing up liquid but its such a slow puncture taking a week to loose 10 psi so don't know if i would spot it or not (trying to save work re taking the wheel off at the mo) as that would be a first for me and i don't want to mess the alignment if i can help it!

Thank for getting back to me

Just realised that this has all been said already, but here it is anyway:

Caretaker wrote:
...only 24psi after about 1week. :shock:

Well, traditionally there are three common reasons for this:

1. Puncture
2. Leaking valve
3. Badly seated tyre

Item 1 - I'm guessing that you have looked for a puncture - if not it is worth a look.

Items 2 and 3 require slightly more fiddling to fix and probaly the services of your favourite garage (unless you are somewhat handy with tyre levers). Starting with 3 first - this is usually caused by a buildup of crap and corrosion around the tyre bead and can be fixed by removing the tyre and then using a wire brush. While the tyre is removed you can fix 2 - just replace the valve!

My local mechanic might charge somehting like (say) 15/20 quid to remove the tyre, clean the rim and refit and change the valve, so it might be worth equiring.

Caretaker wrote:
It is irritating as it means every trip i do so far starts with a trip to the garage to get it pumped up.

I'm guessing that you've got a tyre pressure gauge and some kind of pump, if you haven't now is probably the time to get one. Those ones at garages a quite notoriously inaccurate...

Caretaker wrote:
I have set them so far at front 29psi/ rear 36psi

Sounds good to me, unless you have BT45s, which need somewhat more.

well Its still going down..went out yesterday and it had lost 10psi in a week again.

Yes i took it to the garage/mechanic and paid them £23.00 a couple of weeks back but still has the same prob
They are BT 45's tyres

I use 36 PSI front, and 42 PSI rear on my BT45's, and these pressures work well Caretaker.

Hope you find out what's making the pressure drop though.

Tyre sealant might be worth a shot.

No, I dont have my own footpump so I went out today and did the usual visit to the garage to pump my tyres up..they were on 29psi/ 36psi yesterday and today the rear was already down to 29psi..so I have decided to up the pressires a bit to see if that will help seal the tyre bead..

so I'm on 30 psi/40psi at the moment as I noted the point about higher pressures on BT's

I remeber once having a car tyre that was a bit like this and the tyre fitters just pumped it to about 55psi and left it for a day and then let the pressure down to what was wanted and it helped seal the tyre bead..so will try that next i think...

and then set that at 36/42psi as mentioned.
Who knows it could be that they have been set at this in the past so they need a bit more than the staed 29/36psi thats on the frame

anyone tried tyre sealant?

Had a great ride today....the bike felt so much better with 40psi in the back tyre!

Your alot better off going with the pressures bridgestone supply. The ones listed on the frame are assuming your still on original tyres

I haven't tried sealant on motorbike tyres yet but its pretty standard practice for mountain bike tubeless set-ups as the rubber can be a bit porous without it.

I have goop in mine and its great at holding the pressures. Might be messy when I have to change the tyres next, but it gives me peace of mind knowing that if I do get something in the tyre it's not going to deflate. Makes checking the tyres regularly even more important though, as you might not notice you've had a puncture otherwise.

http://www.mandp.co.uk/productInfo.aspx?catRef=507023

Caretaker wrote:No, I dont have my own footpump

If it were before Christmas I would have said 'a footpump and pressure gauge would make a good present' :)

More seriously, given that you've noticed how much better your bike handles with the correct pressures, for the want of a few quid...

I've previously used a bicycle pump, which can be a bit tedious, but isn't too bad if you only have a put in a bit... even if you are going to use the airline from a garage it's still a good idea to get a pressure gauge!

Caretaker wrote:
I remeber once having a car tyre that was a bit like this and the tyre fitters just pumped it to about 55psi and left it for a day and then let the pressure down to what was wanted and it helped seal the tyre bead..so will try that next i think...

This might work - it all depends on what the problem is. Probably worth a try.

Hi mate
just to let you know that if you are running bt45s on your cb500 the recomended pressures from bridgestone themselves is 36psi front and 40 psi rear hope this helps
regards fozzy

Don't You have air compressors on petrol stations in UK? Easy and cheap way to have proper pressure in tyres.

SzymonCB wrote:Don't You have air compressors on petrol stations in UK? Easy and cheap way to have proper pressure in tyres.

Yes we do thankully
I think the guys are talking about pumping up the tyre if it's flatter than a witches tit!