from the rubber or the metal part of the valve? you can take valve out it is possible that yours has worked loose, or if it is coming from between the rubber and the metal then there could be a punture in the tube and the air is escaping from the only place it can. Check your tyre for anything stuck in.
It's not tubeless like a car [i assume you know !]
So wheres the air coming from ?? The inner tubes the only place.
So the valve is not screwed into the tube / mouth whatsit of the innertube ! Or the valve is jeffed !
Or like Woll said .. you have a puncture & the airs coming out of the tube into the tyre, then out round the valve hole .. the valve holes not supposed to be a seal !
TBH the airs more likely to escape through the spoke adjusters .. they aint airtight like BMW GS spokey wheels !
Confused ?
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Blue - DT 125 RE - '04 - First Of The Leccy Start Lanza'Like Bikes !
and the air APPEARS to be coming from the 'seal !' between the valve & the wheel !
It's probably because the valve tube which come from the inner tube is torn [ this happens a lot off roading on low pressures, as you hammer it ... the tyre spins a couple of mil' on the rim .. drags the innertube with it & tears the valve stem / tube off !
It's a bastard when your 12 miles from home & muddy ..
Rimlocks Help Stop This ... but are $hit on the road, as it's impossible to balance the wheel ... vibrates like hell @ 60mph !
You need a new Inner Tube !!!!
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Blue - DT 125 RE - '04 - First Of The Leccy Start Lanza'Like Bikes !
new tubes no more than a tenner and swaping the tube is easy most bike garages shout fit it for a tenner or less not much point having rimlocks on a dt unless you are running under 10psi on a trail tire
new inner tube it is then, luckily i live next to a petrol station and can pump it up before work, i also happen to work next to a garage so can pump it before i drive home,
Will get new innertube today after work, i have damaged it putting my chain through the back wheel to lock it up, will have to be more careful in future
Robin .. I dunno if there is even the holes in the rim for em' ? Huge steel / chromey things they are !!
Gee.. Still a wierd one m8 .. If you had damaged tube 'neck' .. i would expect it to leak fast ! Inner tubes tend to go down pretty quick once they are compromised !
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Blue - DT 125 RE - '04 - First Of The Leccy Start Lanza'Like Bikes !
yeh ther are the holds for rimlocks but unles you go serious green laneing etc i dont think thay are realy need on a dt125
when you fit your tube you get 2 nuts usalys sompepole titen them up to the rim if you titen them up to the dust cap atleast you will have some warning if the tire is sliping on the rim i dout this is the problem it usaly hapens fast taking the valve off the tube