Sunday, November 28, 2010

Bike component entropy.

Dammit. You'd think what with owning a few bikes i'd be able to keep one of them in working order. Not so much!...

After a stunning ride on friday in the Trossachs, i decided to pull the tubeless system i had been trying to use. I'm not a massive fan of nasty chemicals, so for a while i had resisted using the ammonia based sealants. Instead, i have been using Effetto Mariposa cafe latex with some ground up PVC and stuff in it to act as clotting/matting agent. For the most part it has worked well, though i have still punctured (which at times has been pretty exciting - at this years 10 at Kirroughtree, where a blow out due to a split side wall nearly spat me off the trail).

However, i had been getting fed up with surfing all over the trail due to the panaracer and maxxis tyres i had been using clogging up as we came into winter. So it was time to slot on a pair of Conti Mountain Kings. But it was clear that sealing them was going to be an issue due to porous sidewalls. Nevertheless, a touch of superglue here and some judicious shoogling there got em good to go.

Until half an hour into the ride, when the rear tyre lost pressure. Then again on the homeward bound end, the front lost pressure several times and required a tube (fortunately i had 2 with me). Yes i could fouter around with it a bit longer, or use a different sealant, but i decided to just stick a tube in there. New technology 1, old technology 2.

So i got home and washed out the tyres, talc'ed it all up and slotted in some mid thickness 26" tubes and pumped 'em up. While doing so, i was holding the spokes and BAM! one of the nipples shattered across the 'shoulder' section. Normally with aluminium nipples this is a sign that the spoke is too short: not supporting the full length of the threaded section of the nipple. But on inspection the spokes were the correct length and all was otherwise well. No corrosion found, alignment good. Hmm...

So i replaced the nipple, trued the wheel up and BAM! another went. I know a lot of folk have negative opinions of aluminium nipples, but having used them for many years now in all sorts of conditions i have never had any problems. Indeed, a certain wheel fanatyk, whose opinion i hold in high regard, would back this faith up.

Anyways, with another potential ride on the horizon, and no other working off road bike, i needed to rebuild the wheel quick sharp to get it in order. No worries! i tend to keep an array of spokes and nipples kicking around, so i rebuilt it with dt comps (it did have supercomps - i wonder whether the narrower gauge spoke or perhaps the stan's non eyeletted rim with the massive distance between flanges on that wheel were partly to blame?) and prolock brass nips. Gaining some weight, but also longevity. Old technology 3, new technology 1.

When i popped it back on the bike i realised something was up wit the fork. It looked like the bike was straining at the leash. On closer inspection i had no available travel - it was essentially locked out. I had noticed that the spring rate was increased on the last ride, but put it down to the cold weather. Clearly this wasnt the reason!....The negative spring chamber had lost all pressure. The valve core was tight and i could see no other reason for this. On pumping it up, it drained in minutes. Hmm!...

I then emptied both +ve and -ve chambers and again pumped it up...still no benefit. Ok, i think, maybe there is a micro leak in the i let the +ve chamber out, pump up the -ve chamber and dribble some water over the valve. No bubbles, but POP! out comes the stanchion seal and wiper. Thats not right is it? I reckon it is an internal seal, something Rebas have a bit of a rep for, so the fork needs to go to a professional for a look-see.

So. After all this i'm thinking i need a simple bike to act as a back up. A singlespeed, basic components, you know the drill....except i have 3 and they are all in need of work to get 'em rideable....Dammit! New technology 1, old technology 1.

Are my bikes seeking solace in entropy? You just cant win can you...


muddytrail said...

It's bad karma due to you moving away from the Holy Grail that is rigid ss!

(sounds like a bloody nightmare btw!)

BUCK said...

I like the old tech stuff, tubes and the like. Yeah sure I fix a few more flats than the tubeless dudes, but no messy clean up has been worth it thus far. I might drink the cool aid soon to see how it really is. I have also been shifting a 3 x 8 set up since the beginning of October. How's that for old tech stuff?

dicky said...

I had a similar issue with alloy nips on a road bike. One after the other pulling apart. Sucked.

Never had it happen before.

Replaced with all brass nips.


Anonymous said...

Fork suspension = 0
Fork rigid =1

Score now old technology 4 :)