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General Category => General Discussion => Topic started by: spanner on June 20, 2016, 03:04:41 PM

Title: tyre preasure issues ....
Post by: spanner on June 20, 2016, 03:04:41 PM
Howdy,

sooooo ...... I have had a long standing issue that i have been putting my head in the sand with.

I seem to lose pressure on both tires over the course of three to four days. Most notably on the front but also on the rear.

i have the pressure up to 42 psi on cold tires ..... i live 200 meters from the servo.

with in 3-4 days the steering on the front is so heavy that I need to go and re-pump the suckers.

The front is often as low as 36-37 psi and the rear will usually last five to six days before reaching a sub optimal pressure.

This has happened on both the old Angels and the new 'thingamys" .... there good ones! just have mind blank right now.

Is this sort of drop in pressure over such a short period normal?

does anyone have their own pump either at home or on the bike they use regularly?

I was thinking of getting one of those lower end pumps from the car part shops for around 30 -40 bucks and have it permanently on the bike so i can easily fill with out having to go to a servo all the time.

Thoughts??

 :OldMan
Title: Re: tyre preasure issues ....
Post by: tj189 on June 20, 2016, 03:16:21 PM
I do not believe that is normal at all. 

I am running the Angel GT and the 42psi in the front wheel sits there for weeks on end, the back wheel is a different story, I loose 2 or 3 psi over a couple of days but that is because I have a slow leak from a puncture  :||||  interestingly it will sit on 37/38psi for four or five days.  I must get it fixed.

would they need reseating onto the rim or maybe change the valve?
Title: Re: tyre preasure issues ....
Post by: HunterTodd on June 20, 2016, 04:11:39 PM
Bummer about the leak must be as frustrating as hell. Can't help there but i did buy a cool little 12v pump off fleabay. Cheap as chips and blows like a champion. Came with it own carry bag and quick connect air line.
Title: Re: tyre preasure issues ....
Post by: gaz on June 20, 2016, 04:13:44 PM
Howdy,

sooooo ...... I have had a long standing issue that i have been putting my head in the sand with.

I seem to lose pressure on both tires over the course of three to four days. Most notably on the front but also on the rear.

i have the pressure up to 42 psi on cold tires ..... i live 200 meters from the servo.

with in 3-4 days the steering on the front is so heavy that I need to go and re-pump the suckers.

The front is often as low as 36-37 psi and the rear will usually last five to six days before reaching a sub optimal pressure.

This has happened on both the old Angels and the new 'thingamys" .... there good ones! just have mind blank right now.

Is this sort of drop in pressure over such a short period normal?

does anyone have their own pump either at home or on the bike they use regularly?

I was thinking of getting one of those lower end pumps from the car part shops for around 30 -40 bucks and have it permanently on the bike so i can easily fill with out having to go to a servo all the time.

Thoughts??

 :OldMan

that green Tyre goo Shiny uses seems to slow or at least hold psi goodly  :fp
Title: Re: tyre preasure issues ....
Post by: ST2UP on June 20, 2016, 04:47:36 PM
That sort of loss is quiet dramatic....If we don't use the bike for a month it will loose no more than 2psi.

Everything from a puncture causing a slow leak or a poorly seated bead through to porous cast alloy wheels can cause air loss.

Compressors are relatively cheap....I use a small ? Tomcat compressor, but there are so many variations on the same theme.


 :beer
Title: Re: tyre preasure issues ....
Post by: StinkyPete on June 20, 2016, 05:27:09 PM
Spanner, have you tried searching for a leak with very soapy water.   Drench the areas around the valve, beads and tyres, as a leak that big should show up.    Check your valve stems for cracks, and keep in mind that it's recommended that rubber valve stems are changed at every tyre change.
Title: Re: tyre preasure issues ....
Post by: cravenhaven on June 21, 2016, 08:19:18 AM
The last couple of times I've had a new tyre fitted, I've noticed that the valve has not been changed. I thought this was a legal requirement but apparently only for car tyres, not bikes ???.
Title: Re: tyre preasure issues ....
Post by: StinkyPete on June 21, 2016, 08:29:57 AM
The last couple of times I've had a new tyre fitted, I've noticed that the valve has not been changed. I thought this was a legal requirement but apparently only for car tyres, not bikes ???.

I understand that it is not a legal requirement, but is strongly advised.   I was having a new rear fitted while in Cairns, and the dealer noticed that the front valve stem was cracked nearly all the way through, which cost me a refit of the front tyre as well.  It was lucky he spotted it.    My local fitter did not replace the valve stems as a matter of course, but on mine, he does now. 
Title: Re: tyre preasure issues ....
Post by: Scarlett Thunderbolt on June 21, 2016, 09:11:39 AM
  Hey spanner, Pete's soapy water idea is a good one - straight out of the workshop techniques for finding leaks in tyres, air-cons and truck air-ride and braking systems... a mechanic with a squirt-bottle of soapy water, squirting an air-line, looking for telltale bubbles indicating a leak. If you do replace your valve stems, right-angle valve stems are a good piece of kit,  that come highly recommended.

  We use a Ryobi battery operated compressor (from Bunnings) because the battery is interchangeable with my drills and sander, etc... Good for every tyre from our wheelbarrow, up to the car. It's digital display shows air pressures in 0.5psi increments, up to a 70psi max. It is carried in the top box when we go out for a ride, where it is also used to inflate the air mattress in the camping equipment. Seeya, John.
Title: Re: tyre preasure issues ....
Post by: spanner on June 22, 2016, 09:05:14 PM
Thanks everyone

Some great replies.

The valve stem was replaced when I did the new tires and it was with the 90 deg one. Best thing EVER putting that on.

Since it happens with two sets of tires I wonder if it is indeed a porus run or maybe there is a little nick in the bead seat or something.

Will have to do the soapy water trick ..... Can't believe I did not think of doing to the motor bike what I tell the kids to do to their push bikes!   :fp

Cheer every one and will let you know   
Title: Re: tyre preasure issues ....
Post by: Sicman on June 22, 2016, 09:44:39 PM
 :think1 This was discussed on the forum a while back - 3 of us noted that after a month on the PR3"s the tyres dropped 10psi over a month.

The PR4s aren't as bad but will drop 5-6psi. We came to the conclusion they are just more porous. I note that I haven't lost as much pressure since the bike has been sitting in my new insulated shed either.  :thumb

After riding thru copious amounts of water laden roads, and dirt holes last weekend, for hours on end, I have utmost confidence in the PR4's to go where they are pointed, even in the deepest of water  :thumbs Not once did the bike slow up or shudder when hitting puddles or sheets of water, or flood water  :clap and at no stage did I feel any front wheel slip  :clap

They are a seriously great tyre in the wet  :thumbsup

 :slvr13
Title: Re: tyre preasure issues ....
Post by: spanner on June 25, 2016, 08:53:04 PM
Just about to get some PR4's on Monday for the ride South.  Was going to replace them on the return as I thought I still had a few thou left on them but the rear was through the rubber on my proper inspection two days ago!

I got 17000km out of them.

Is that reasonable?
Title: Re: tyre preasure issues ....
Post by: Sicman on June 25, 2016, 09:56:24 PM
17K is quite respectable. Road conditions in all areas will vary as will how you maintain tyre pressures etc. With practise you will get up to 20K or better  :thumb
Title: Re: tyre preasure issues ....
Post by: Kev Murphy on June 26, 2016, 07:24:00 PM
I always carry my compressor, everywhere. Only 6 inches long, 5 inches high.. fits in a bag with a thread puncture repair kit in lefthand pannier

(http://i1029.photobucket.com/albums/y352/kjm47/Bikes/Dscf2526_zps4ilnto5c.jpg)
Title: Re: tyre preasure issues ....
Post by: spanner on June 27, 2016, 09:07:19 AM
I always carry my compressor, everywhere. Only 6 inches long, 5 inches high.. fits in a bag with a thread puncture repair kit in lefthand pannier

([url]http://i1029.photobucket.com/albums/y352/kjm47/Bikes/Dscf2526_zps4ilnto5c.jpg[/url])


I am going to be getting one of these this week before my IBA to Parkes.

Have you had to use it and how much was yours? and where did you get it from?
Title: Re: tyre preasure issues ....
Post by: cravenhaven on June 27, 2016, 10:50:05 AM
I use a slime pump. http://slime.com.au/shop/power-sport-tyre-inflator-40001/ (http://slime.com.au/shop/power-sport-tyre-inflator-40001/)
Title: Re: tyre preasure issues ....
Post by: Kev Murphy on June 27, 2016, 11:19:32 AM
I picked up the compressor along with the repair kit for around $50 in a local camping/disposal store. I use the compressor to check tyre pressures every week or two, and top up if needed. Have used the thread repair kit in the past to repair a deflated rear tyre on the road caused by a screw piercing on the highway near Hay, and assisted a stranded motorist with a flat on the freeway south of Newcastle in 2009. Replaced it with a new thread kit about 3 years ago after repairing and re inflating another bikers tyre west of Ballarat. New kit has not yet been used.
Title: Re: tyre preasure issues ....
Post by: Wild Rose on June 27, 2016, 11:53:20 AM
I use a slime pump. [url]http://slime.com.au/shop/power-sport-tyre-inflator-40001/[/url] ([url]http://slime.com.au/shop/power-sport-tyre-inflator-40001/[/url])


Got one. Used it a couple times on the road and just checking tyres before a ride :like
Title: Re: tyre preasure issues ....
Post by: Sicman on June 27, 2016, 11:55:57 AM
Yep my slime pump is 6 years old and going strong  :thumb
Title: Re: tyre preasure issues ....
Post by: StinkyPete on June 27, 2016, 12:57:20 PM
I've got one of these......
http://www.rockycreekdesigns.com.au/tyre-accessories/motopressor-tyre-pump.html (http://www.rockycreekdesigns.com.au/tyre-accessories/motopressor-tyre-pump.html)
It's nice and compact and works quite well.