Warning about metal valve caps.

[Throttled]

They can weld themselves on to the valve. I am talking about caps like this

http://www.superforma.co.uk/media/catalog/product/cache/1/image/650x/040ec09b1e35df139433887a97daa66f/g/o/gold_valve_caps__medium__1.jpg

I fitted them to both my bikes, I used ACF50 since there is a known issue, but it did not stop them from welding themselves on. So far one was stiff but came off, one had to be cut off, one has come off with the valve so I need a new inner tube and I have one more to try and remove.

Edited May 16, 2015 by Throttled

[Stu]

I have known this for years

I found out by my brother doing the same thing

[fullscreenaging]

Surely they will only weld themselves on if you're not checking your tyre pressures regularly?

Or this could happen over winter when not riding.

[Throttled]

Surely they will only weld themselves on if you're not checking your tyre pressures regularly?

Or this could happen over winter when not riding.

 

Both bikes are used in bad weather, one more so than the other and both happened in the space of a month.

[Stu]

yeah it doesnt take long for these to become stiff!!

I think its a reaction with the different metals that causes it

[Throttled]

I think that what happened is that I got lazy squirting a bit of ACF 50 into the valves before I put them back on and then they welded. All four in one go after no issues for over a year. They are being replaced with plastic ones, 12 for 99p off eBay.

[Tankbag]

yeah it doesnt take long for these to become stiff!!

I think its a reaction with the different metals that causes it

Dissimilar metal corrosion, these must love the valve stem though !

[mattycoops43]

A smear of grease solves it though.

[rice-pudding]

I think these cheap caps are aluminium and they react with the brass values and "weld" together. Don't buy crap! I did once and had to get brand new valves fitted on my car tyres

[fq-craigus]

I have metal caps on my car, but they are stainless with o-ring seals, i had some cheap novelty type r ones on my old car and they fused to the valves (didnt check tyres for ages) had to get a tyre shop to replace the valves in the end

[Guest]

yup it's a reaction between the metals. Simple solution, once a week pop them off give them a blow and then pop them back on. It'll stop them from getting stuck.

[rice-pudding]

I'd rather spend the couple of extra squid and buy steel ones, saves time and money in the long run.

I have nice yellow ones on, designed for HGV's. No more crap gets in there

[whitedevil]

copper grease should stop them stickibg