Johan Bornman

I sincerely doubt that it is a case of coming back worse than what it went in. There is almost nothing one can do other than malicious mischief, to make a fork leak. It if wanted to leak, it will leak. You may not have noticed the leak before or, a little bit of movement could have been the last straw. Perhaps it was left upside down. However, I'm certain it is not of their doing. Whether they should have phoned you and asked if they can repair a fault that they noticed, is another matter. Dont be too quick to shoot the mechanic.

UST stands for Universal System Tubeless (it sounds stupid 'cause it's translated from French). It is a joint trademark by Mavic, Hutchinson and Michelin - all French companies. You can license the trademark, a little bit like you putting the Heart Foundation logo on your beer, but then you have to conform to certain standards. Loosely stated, the UST consortium requires a thick juicy tyre bead, a thick juicy sidewall and a tread area that is completely sealed underneat. Such a tyre should seal and run, without the use of sealant on any suitably-sized clincher rim which had its spoke holes sealed. In order to have the UST logo on your tyre, you pay someone a license fee. That means that some tyres may technically be UST but doesn't have the logo. I don't know of such a case but it may exist. On the other hand, there is no standard for Tubeless Ready and it is a loose term that could mean anything from "leaks lilke a sive" to "may seal with enough snot inside". You don't have to pay anyone to use that term and you can slap it on anything from fishnet stockings to tyres. The tyre industry is one that thrives on dishonesty and claiming tubelessness is by no means a gaurantee of running a tyre tubeless. I accuse the industry of dishonesty because every single player (except for Avocet) plays a game to fool the weight weenies. They overstate their tyre size in order to come in first on lightness when baaicycle magazines do shootouts with little electronic scales. I've had tubeless ready tyres that won't seal unless I fit a permatube from Makro. At the moment the industry is at a loss with what to do with 29er tyres. Getting a proper tubeless (as in UST-style tubeless) on a 29er is easy. What isn't easy is to get it within an acceptable weight determined by the 29er fraternity. These guys want bigger wheels, yet they insist they don't weigh less than 26er wheels. What they all seem to do is produce inferior (in the tubeless sense) tyres and hope that no-one notices.

Hmmmm. I don't think so.

What happened? There was a leak between the rim tape and the rim itself. Air and sealant leaked into the rim cavity and came out at the nipples. Bear in mind the nipples don't make an airtight seal at the rim. After a while the sealant sealed the leak between the tape and the rim and the air stopped escaping. It had nothing to do with the swimming pool or the lurking creepy crawley in there. What you will find soon is that the wheel will start to leak and sealant will come out the spoke holes. This is because the sealant lifts the adhesive-backed tape and it looses contact with the rim. The process fills the rim cavity with sealant and causes an unholy mess. What is important is that you cracked a cold one and thought about it and your sins. That gave the sealant time to do its thing, albeit at the wrong "puncture". You must now decide whether to do it all over or just let is simmer in its own juices and damn the consequences. If you have aluminium nipples, it is best you fix it properly, it will cause problems with the crappy nipples. If you can't decide, crack a few more frosties and watch some reruns of The A-team. That will take your mind off the mess inside.

You're a victim of the weight weenies. I've disabled PMs because lots of people PM me wanting to engage me in a conversation that involves what stuff weighs. I don't care. johanatyellowsaddledotceeodotzeda

Headsets don't get torqued. You turn the preload bolt until there is no play. This may be tight on some bikes and finger tight on others. The stem pinch bolts should be about 6NM. I doubt his crank has to go to 40nm. I would assume it is a modern crank with the axle attached to one of the cranks. If it is a Shimano, 14NM on the two pinch bolts and hand tight on the preload cap. (vice versa actually, the preload cap first and then the pinch bolts. We really need more information here. For instance, 4mm stem bar clamp bolts (if there are four of them) require about 4NM where as 6mm bolts can probably take 12, since there are only two of them. It depends on the bolt size and materian it screws into. One would have to know whether the sealpost is carbon, the bar, etc etc etc. I prefer to ignore questions with too little information. That way you harm no-one.

I don't have suggestions but would like to look at your bike. Something else is at play here. 9-speed chainrings with 10-speed chain perhaps? I dunno.

This Tokolosh wants to differ with you. I maintain, that the smaller the chainring, the higher the propensity for suck. This is due to three reasons. 1) The smaller the chainring, the lower the chain tension. 2) The smaller the chainring, the more the chain has to articulate, and therefore straighten again, upon release. 3) The hook at the release point is more pronounced. I'm sure you'll figure the first one out for yourself. On the second point, for example, a 42 -tooth chainring requires only eight degrees of articulation at each chainlink. A 26 tooth ring requires 14 degrees of articulation. The work required to untangle an 8-degree bend and a 14 degree bend is considerably more. Hence, a smaller chainring, given all things being equal, will suck more. Thirdly, given exactly the same tooth profile, with a pronounced hook at the leading edge of the cog, the smaller chainring will have a more pronounced hook. Hence more difficult release. Finally, I don't see where the derailer hanger comes into it other than at the catastrophe end of it all, but then you may as well mention spokes, seatstays, jockies and other victims of chain suck.

Kerzactly. However I dont see where confusion could creep in. OP did say semi.

We don't know what your workshop/garage has in the line of equipment but if you have a big vice, you're all set. A carpenter's vice will work really well. Press the cups in one at a time. Protect the frame from the vice jaws with some wood. You will need help since there will be too many things to hold in place. Make sure the cup enters the frame nice and true. If it goes off centre early on in the press, correct it by pressing on the laggard side only until it is square. Once the one cup is in, do the other one, but don't try and press both at once. The headset race is more of a problem. This will easily damage if you force it in with an inappropriate tool. A well-sized piece of pipe will do but the chances of you having one at hand are nill. I'm all for split races, it is a good idea with no apparent downside. If you don't have a vice, your hammer and wood idea is good too. Howver, be ultra patient. Have an assistant at the ready. Hit once and then inspect for true and protect all bike surfaces with wood. If you can solve your headset race problem, the operation should take you 6 minutes. We're timing you.

Yes, but unfortunately the area of attack is so small that full penetration just about never happens. What I mean by this is that the oxide forms perfectly good seal in there and pouring ammonia in only attacks the axial end of the little cylinder of oxide. I'm not sure if my explanation makes sense but it is the converse of say, painting ammonia onto a sheet of aluminium oxide.

OK, now that you've tried everything and blistered your paint, cracked the frame, bust a gut and cursed a bit, do it the right way. Aluminium oxide is the culprit. The post was probably greased before inserted. Water gets in there, forms an emulsion with the grease and then proceeds to corrode the alu. Aluminium oxide is a larger molecule than an alu molecule and therefore the alu oxide crystals expanded inwards, trapping the post. No chemical process will reverse this and no penetrant will work. Force may or may not work. Saw the seatpost off, about 25mm above the top of the seat tube. Now insert a hacksaw blade with the one end wrapped around a cloth and proceed to saw the seatpost lengthwise until you touch the frame. It is a long, laborious job but gets shorter with beer. Be patient, do a decent job and don't inhale that horrible carbon dust and don't get carbon splinters in your fingers. Once the seatpost is now sawn through, tap it with a mallet and it will pop right out. The reason why it can now get out so easily is because the corrosion doesn't bond it, but just expands. With a groove in there it can expand inwards and come loose. PS - I notice no-one has suggested the Coca Cola remedy yet? C'mon, get with it!

Yup, and when you get tired of it or it gets ugly, you can remove it with petrol, whisky, diesel, paraffin, acetone, spray and cook, Q20 or that other nasty brown vile fluid....Nescafe. Carbon is impervious to anything you* can throw at it. *Disclaimer: this statement holds true for the average household. We once had a chemistry prof here who kept some pretty nasty stuff under his kitchen sink that could harm carbon and kill a horse.

Patches, write to Castrol locally and ask them for the data sheet on Castrol LHM Mineral oil. They have to send it to you by law - it is probably on the website anyway. That is exactly the same as Shimano's and you'll have your answer. In the hydraulic oil business the W in 10W or 5W means nothing. It is a bit like small, medium and large. Not defined. Viscosity is indicated in centistats at a given temperature.

Try some punctuation and capitalisation. It is important. It could mean the difference between helping your uncle Jack off a horse and, helping your uncle jack off a horse. Now. That little metal plate is only to prevent most of the scratches and scrapes that a sucked chain causes. Chainsuck is a tri-partiate alliance: dirt, wear and chainring size. Dirt: The more of it, the more the chainring will stick to the chain. Wear: The more the chainring is worn, the greater the hook effect will be and more frequent the chain suck. Chainring size. For a given amount of wear, a smaller chainring will suck more than a larger one because of the hook's angle. The hook I'm referring to is the worn cog* that now looks like a shark's fin. Upside down at the suck side, it is a hook. There are chainsuck devices on the market. These bolt to the BB or such and prevent the chain from passing it. I'm not sure if they're effective. Never used one. Chainsuck doesn't know if it emanated from double or triple chainrings. It only sees the three factors above. A temporary solution could be to file off the tips of the hooks. *A cog is one tooth on a gear or sprocket.

You can attach it with anything other than bolts or pop rivets. You have nothing in your garage, under your sink ior in n your drinks cabinet or your poison store that can harm carbon.

Someone once said that any dork with a CAD program can design a standard and nowhere is it more visible than with headsets. The original headset spec called for cartridge bearings with a 36 and 45 degreee chamfer on the inside and outside. However, the likes of Ritchie, Chris King, Campagnolo and others have raped the standard and came up with strange angles. Therefore, the headset may be cheap but if no-one carries spares for it (including spare crown races), it becomes obsolete at its first service. The golden rule with headset choice is to see if the bearing is a standard 36/45 degree bearing. If not, run away from it.

0823086847

Yes, standard grease is fine. There is no such thing as waterproof grease and marine grease just copes with salt a bit better, but doesn't make things waterproof. A cartridge bearing can be sealed or unsealed. Im this picture there are many cartridge bearings. The ones with blue bits in are sealed, the others are unsealed. The specific type of cartridge bearing in this photo is a deep groove bearing. You also get roller bearings, double row ball bearings, self-aligning ball bearings etc - all in cartridge bearing style. The seal may or may not be required, depending on its use.

If your chain was worn to or beyond the 1% elongation point (approx 1/8th of an inch), then your new chain will NOT work with the old cassette and will jump on your frequently-used gears as Stretched found. Any new cassette will work perfectly with any chain worn below the 0.5% mark. Period. Shifting has nothing to do with chain wear. A worn drivechain can shift perfectly. The cheapest way to run a healthy drivetrain is to replace your chain at the wear limit point with the cheapest possible compatible chain. The most expensive way to run a drivetrain is to let everything go.

Guys, don't confuse a sealed bearing with a cartridge bearing. Cartridge bearings can be sealed or unsealed. Cup and cone bearings can be sealed or unsealed. Therefore an unsealed bearing can't be equated with cup and cone bearings and a sealed bearing cannot be equated with a cartrige bearing. A note on Fulcrum wheels - some Fulcrum MTB wheels use extremely expensive proprietary cartridge bearings that you won't find at any old Bearing Man.

Why?

This is a pretty common problem and one that is easily fixed with the right tool - but only the right tool. Your jockey hanger is bent. The bike was dropped on its right side and the hanger is bent inwards. Find someone with a derailer hanger straighter and have it done professionally. You could attempt to simply fit a new hanger - they're removable and sacrificial, but the underlying frame structure may also need attention. No use fitting a nice flat new hanger onto a bent frame section. It is always a good idea to carry a spare hanger with you. Hardcore okes wear their spare like a piece of obscure jewellery around their necks on a leather thong.

Beats me, she obviously hasn't seen my dog operate on car rims.

StevieL, I'm sorry I somehow overlooked you. I can't put name to profile so to speak but if you e-mail me I'll do good on you.