i have a silly dust cap problem

Because its probably got a better chance than boiling water

[ophic]

Originally Posted by fastdruid

Penetrating oil . Average load .. Price per fluid ounce
None ................. 516 pounds .
WD-40 .............. 238 pounds .. $0.25

surely that's gotta be why.

[fastdruid]

Originally Posted by The Guru

Because its probably got a better chance than boiling water

Boiling water will cause the cap to expand[1], ideally expanding enough to free off what is presumably the corrosion attaching it to the stem. Using a naked flame is either asking to be burnt, set fire to the stem, blister the paint or all three. WD40 as previously stated is *not* a penetrant so will do virtually nothing unless there was little wrong in the first place. BTW that test was after *soaking* the parts for 8 *hours*.

Druid

[1] I'm not sure what the metal the thread on the valve is made from but I presume either steel or maybe brass, both of which have a lower Coefficient of Thermal Expansion[1] than Aluminium - http://en.wikipedia.org/wiki/Coeffic...rmal_expansion

Looking at the picture it seems to be cross threaded-----let the tyre down, break the rim seal, cut the old valve off and fit a new one and blow the tyre back up to the proper pressure.
Apart from the MOT Examiner being able to refuse it is dangerous to ride if it is so under inflated that you are worried about it passing the MOT.

Virtually nothing or nothing? There is a difference.

And yes tyre valves are typically made out of *Brass*

ive seen people loctiting these on so they cant be nicked bit stupid because then you can get the proplem uve got. proberly have to get the valve changed

Originally Posted by yorkie_chris

And don't forget to bitchslap whoever put such tacky chavness on there

Strange that. It is possible to get those in black too and Bridgestone actually recommend metal caps with o-rings because UNDER LOAD (i.e. riding), a trye can go down very quickly without a cap fitted.

That's what the man says and he knows better than I. Don't fancy doing a test either before some wisearse suggests it.

Garry

wasn't cross-threaded, was just corroded in place, new valve on it and MOT passed

At least when its stuck on no one can nick them

Originally Posted by Holdup

At least when its stuck on no one can nick them

i had some nice dust caps that even said SV650 on the top and then i went to portrush for the nw200 and came back to the bike and they wer gone........gurrr