pain in the arse day:
One of my colleagues wanted the tyre changed on his VFR800 so i said swap bikes and ill do you tyre when i get home. So yesterday evening-despite being knackered- i went out and took the old tyre off [which was a bit of extra work as the bead has taken a liking to the rim and didnt want to break off] and put the new tyre on.
Left for work on it - nice and steady, new tyre, wet, not my bike- on the M48 just past Aust the back end starts wiggling. Pull over to a flat tyre. look to see the valve cap mangled. Panic as I dont have recovery for it. So phone my best mate who crosses the border at 0710 like me. He's just behind me [he stopped on the roundabout to call me back] and he comes up with a tyre valve [he had a spare inner tube for his trailer and a valve key on the end of a can of goop] so we swap valve cores and use his Dacia inflator to bung 50psi in. Off i go and thank him and give him a wave as he heads to Falfield and me to work in Stoke Gifford. Arrive to a worrying colleague as i had texted him to say shit was going down. Not even late!
Anyway we go and check it at lunch and it's flat again. ffs no.2. He has a free after lunch so he lobs another 50 psi in it and I follow him back to mine. At this point me, my mate and my colleague assume it's my shoddy workmanship and i've minced the valve in my tiredness and haste. Back at mine we take the tyre off put another valve on and he's good to go. He's got an MOT first thing [the MOT place is 100m from my house] so he says he'll pop in for a coffee whil-he-waits.
20 mins later he's phoning me - its flat again ffs no.3, so i stick the trailer on my car grab my lash down gear and head to him to trailer it back. By now we are both pretty pissed off, but he's a fantastic colleague (maybe the best person ive had the pleasure to work with] so i am happy to help him get sorted. We trailer back to mine and he heads off home on my bike again.
Being an engineer and not a slacker I decide to find out why it's gone flat again. I stick in on the centre stand and the beads are located fine it isnt that. But hello, what's this? the valve cap almost has a nick in it (the valve that failed this morning had a damaged cap and the centre pin had gone) and looking the valve core is missing the detent bar. Eureka!!!!! the valve is hitting something on the way around - it's single sided swing arm and the valve is on the centre line like the torsion arm, caliper and carrier. It's whacking the carrier every revolution. How either valved survived 8 miles this morning and this afternoon is testament to the good elasticity and resilience of the stem and body.
Ill have to go to the tyre depot at 8am and get a short valve so we can have it ready for MOT at 0910.
What a bloody day. Was beginning to doubt my own workmanship - never a nice feeling.