Wednesday 14 December 2011

Winterproof Your Bike 3: The Rest

In Parts 1 and 2, we looked at easy (yet very thorough, according to feedback from readers!) ways to ensure that the chain and headset, two of the most delicate parts of the bike, continue to function smoothly throughout the winter by protecting them as far as is possible from the weather, moisture and salt. In this article, we'll look at protecting the rest of the bike. Depending on where you live, it's not essential to carry out all of these tips - if, for example, you live in a relatively dry climate such as lowland southern Europe or the southern USA, just basic protection will see you through the winter. If you live in an area that experiences heavy snow or rainfall, use all of the tips and your bike should keep going through to spring.

The Seat Tube
Moisture can find its way into the frame via the join
between seat pillar (black) and seat tube (silver)
(image credit: Keanu4 CC BY-SA 3.0)
Given enough time, moisture can find its way through the tightest gaps - and when it does, corrosion isn't far behind. That includes getting into the seat tube, even though the seat post is tightly clamped within it; and once it's in there it'll make its way down to the bottom bracket cluster, the most inaccessible part of the bike. Fortunately, it's one of the easiest parts to seal up due to the lack of moving parts.

First, unfasten the seat clamp and remove the seat pillar from the bike - use a marker to draw a line at the point where it emerges from the frame before removing it, even if you're sure you'll remember the correct height (some pillars have lines etched onto them), the reason for which will soon become obvious. While it's out, you may as well give it a quick clean - wipe or spray it with degreaser, wipe again with a  clean rag and then put it to one side. Using a rag fixed to a rod, use degreaser to clean the inside of the seat tube too.

In the article on sealing the headset, we used sections cut from an old inner tube to make a rubber barrier to keep water out. Did you keep the remains of the tube? Good. Cut another 11cm (4") section from it (note: this is only going to work if you have a non-quick release seat clamp or the quick release type with a removable lever. If yours is quick release with a non-removable lever, leave the inner tube unmolested). Now that the seat pillar has been removed, stretch it over the top end of the seat tube, rolling down to the top tube so it's out of the way.

Go back to the seat tube as the degreaser should by now have evaporated away. Apply some good quality grease and smear it over the part that will be concealed within the frame, making sure the entire lower part is covered and taking care to avoid a section beginning 4cm from the point you marked earlier - the pillar is clamped only at this point, so the grease will protect the remainder from moisture without making the pillar slide down inside the frame. If you have a titanium frame or seat pillar, use ti-prep compound instead - titanium and other metals tend to squeak otherwise.

Now slide it into the frame, using the clamp to fasten it a few centimetres before you reach the desired insertion point. Apply a thin layer of household silicone sealant to the 4cm section below this point, then loosen the clamp and insert the pillar to the correct place and refasten. If the sealant hasn't formed a complete ring around the top of the seat tube, apply a little more to form a complete seal - you can also use it to seal up the slot cut into the seat tube just below the clamp. Let it set: the time it takes to do so will be listed on the sealant's packaging. It'll form a complete seal but isn't strong enough to prevent you removing the pillar in the future.

Pick off any excess sealant that has dripped onto the frame, then unroll the section of inner tube so it covers the top section of the seat tube, covering the seat clamp. Use two plastic zip ties, one below the clamp and one above it, to tighten the ends. Your seat tube is now completely sealed from the weather.

If your bike has internal cable routing, as most road bikes and some mountain bikes (notably Klein) do, moisture can get into the frame via the cable entry holes. Many people are reluctant to fiddle with internally-routed cables for fear that they won't be able to run them back through the frame after removal. In some cases, the cable runs through a tube inside the frame which makes refitting a doddle, but care does need to be taken with "free running" cables when there is no tube running from entry to exit point - in this case, the trick is to ensure that there is always either an inner or outer cable running through the frame.

The internal cable routing can be clearly seen on this Orbea
(image credit: Marcela CC BY-SA 3.0)
To remove old cables, unfasten the cable from the brake or gear mechanism and then - having instructed your glamourous assistant to hold onto both ends of the outer and, on pain of death, not let it come out - pull the inner through and out, having snipped off the end with cable cutters if it's frayed. If you're not going to replace the outer, squirt some light oil (the kind that comes in an aerosol with a little plastic tube to allow you to squirt it into tight spaces) into both ends of the outer. You can then thread the new inner through the outer, using it as a guide. If you will be replacing the outer, carry out the same process but don't fasten the inner to the derailleur or brake. Once it's through, pull the inner taut and then slide the outer through and out of the frame, then off the inner - keep it, as it'll be handy if you need to cut the new one to the correct length. Having applied light oil again, thread the new section of outer onto the inner, then have your assistant hold the inner taut while you slide the outer into the frame. Getting it to poke out at the other end can be fiddly and might require several attempts, but it's a hell of a lot easier than trying to do it without the inner in place.

Pulled the whole lot out of the frame? Well, you should have read this section in full first, shouldn't you? Oh well - how are we going to get the new one through? If your frame has a tube running from entry to exit point, it's a simple matter of threading through a new outer - but if you have free cables, you're in trouble. One way is to use a thin length of stiff wire which can be fed laboriously into the frame and - hopefully - out of the exit point, so that you can fix a piece of string to the end and then use that to pull a section of cable outer through the holes. However, getting the wire through the exit point depends on luck more than skill - if it doesn't work, you might need to visit the bike shop where a mechanic will probably have a pair of very small artery forceps kept for precisely this task. He or she will laugh at you.

If you want to re-use the cables already fitted to your bike or are fitting standard cables, you can use silicone sealant used to create an extra barrier between the entry and exit points and the rubber ferrules that fit into the holes - the ferrules work well, but an extra line of defence won't do any harm.

To seal the cables themselves, be they internally or externally routed, get hold of some thin surgical tubing of a diameter that will slide onto the inners without being tight. Cut it into 3cm lengths, one for each point where the inner cable enters or exits a section of outer cable and slide them onto the inner at the relevant points. These can then be stretched over the ends of the outer cable and provide an effective seal to keep moisture out.

If you want to make sure your cables are completely sealed, invest in Gore Ride On Cables - they're not cheap at around £50-60 per set and fitting them can be tricky the first time, but nothing keeps the weather out so effectively. These feature an inner cable protected along its entire length by a thin polytetrafluoroethylene (PTFE) sheath running through a PTFE middle liner, thus creating a system that both reduces friction to an absolute minimum and keeps the inner completely sealed from the outside world. To fit them, first cut the outer section to the correct sizes (some mountain bikers run a full-length outer from brake/gear lever all the way to the brake/derailleur, thus sealing the system entirely at the expense of increased friction and in some cases having to fasten the cable to the frame with ugly zip ties).

When using sealed cables, it's essential to make sure that the ends of the outer sections are smooth and free of sharp burrs as these will damage the PTFE, making your £50 cables no better than £10 cables. While a good quality pair of cable cutters will cut outers to a satisfactory smoothness for standard cables, when using sealed cables it's advisable to smooth the tips using a fine needle file to remove any sharp edges both around and just inside the hole. If the cutters have crushed the outer, use an awl to make it round again - and pick up some better cutters next time you're in the bike shop. Once done, prepare the inner by threading on the rubber ferrules and outer sections (which, if you have internal routing, will already be in place within the frame provided you followed the guide above). Remember that for a cable to work efficiently, it needs to avoid any acute loops - but outer sections also need to be long enough to avoid interference when the handlebars are turned as this will cause "ghost braking" or "ghost shifting" when the bars pull on the cables.

You'll now need to cut the middle liner, taking care not to kink of damage it - the best tool for the job is a sharp pair of scissors or a razor blade, since a knife is likely deform it. Each section needs to be slightly longer than the the relevant outer section so as to continue into the ferrule and keep everything sealed - the amount varies depending on position and manufacturer, so follow the instructions on the cable packaging. Next, thread the inner cable through the outers. If you've cut it cleanly with a decent pair of cutters, it will usually slide through without any problems; however, to ensure the middle liner doesn't get damaged by a strand of wire that successfully comes loose, it can be useful to scrape a small amount of PTFE from the end of the inner and then apply a tiny dab of solder before using the file to smooth it off.

Once the inners and outers are in place, you'll need to remove a little more of the PTFE coating. The exact amount again depends on position and manufacturer: in the case of Gore cables, it's 2.5cm at the front derailleur and 1cm at both the rear derailleur and the brakes - the instructions on the packaging will provide further details. Finally, fit the rubber ferrules that protect the last section as it protrudes from the derailleur/brake stop, then tighten into the anchor bolt. Finish the cables off with a dab of solder or superglue before rounding off with a file and fit a metal ferrule to prevent fraying (tip: if you find a friendly bike mechanic and ask nice, he or she will often give you a handful of ferrules for free or for next to nothing - you get a lot more for a lot less this way rather than you do if you buy them in a packet). There will be a rubber end-cap for each cable which can be fitted over the ferrule, thus protecting even the last few centimetres.

If you have a workstand, click up and down through the gears and make any adjustments that are necessary with particular attention paid to the shifts from the second-largest to largest cog and second-smallest to smallest for the rear derailleur, as these are ones that if not adjusted correctly can cause the chain to come off. Do the same with the front derailleur - if you have two rings, pay attention to the shift from smallest to largest and vice versa; if you have three rings pay attention to the shifts from middle to smallest and middle to largest for the same reason. It's not possible to apply the same stress to the brakes will experience when the bike is being ridden while it's in a workstand, so ride it a short distance and apply the brakes hard a few times to make sure everything is settled in and tight.

Bottom Bracket
Most bikes today use sealed cartridge bottom brackets, in which all moving parts are securely housed within an outer tube. In some cases, these can be dismantled to allow access to the bearings within, in which case it will be possible to relubricate the parts with grease and keep moisture out. Many are sealed units and cannot be taken apart without destroying them - good quality models will be fitted with one or more internal seals at each end to keep dirt and water at bay.

Square-taper Shimano bottom bracket with removed cup
(image credit: Michael Shields CC BY 2.5
However, steps can still be taken to prevent the winter getting in. The bottom bracket itself - or the type that can't be disassembled, at any rate - is designed to fulfill its purpose for a certain period, then be replaced: how long that period is depends on the manufacturer, the model, the distance covered and the conditions. So, as an example, if the information supplied for Megabikebitz's Model X says it'll last a year, that' a year of whatever Megabitebitz consider to be a typical distance for a year and in the dry - plus a bit extra because they probably want you to buy a new one a little bit more often than you really need to. The simplest way to tell if yours needs to be replaced is rotate the cranks on a brand new bike when you're in a bike shop - that's what your should ideally feel like. If it's a little stiffer, don't worry but start considering replacement. If it's either a lot of effort to pedal or the bottom bracket makes loud creaking noises when you do, then it's time for a new one.

Even if the bottom bracket doesn't need to be replaced, both it and the frame will still benefit from a clean and regrease before winter gets underway. We're going to assume you have the standard three-piece system, because if you have anything more special there's a reasonable chance that you either know how to remove a bottom bracket or employ a mechanic. To begin, you'll need to remove the cranks - if they're fitted to a splined bottom bracket (Shimano Octalink 1 and 2, ISIS and assorted other designs), this is a simple matter of removing the bolts that fasten them in place (either by screwing into the bottom bracket axle or by pinching the crank onto it) after which the cranks will slide off. However, many bikes still use the square-tapered design, in which case the fastening bolts will need to be removed before a dedicated crank puller is used. This tool features an outer barrel which screws into the crank and an inner core that is then screwed into the barrel, forcing a hardened (and in the best models, rotating) tip against the axle, thus pulling the crank off. To remove the bottom bracket, it will be necessary to use another dedicated tool - unimaginatively named a bottom bracket tool - to unscrew the removable cup from one side. The removable cup is often made of plastic or in a different colour to the other end, allowing for easy identification. Different designs of bottom bracket require different tools, so you may need to ask your bike shop which type will be suitable or, if you know the make and model of your bottom bracket, check the manufacturer's website.

Once the removable cup is out, the tool is used on the other side of the bottom bracket to draw it out of the frame - this may require considerable force, in which case it's helpful to place a length of metal tubing over the tool to increase leverage. Slowly and surely is the way - strip the threads and you'll be looking at an expensive visit to a frame builder.

Bottom bracket with splined axle (in this case, Shimano's Octalink 1)
(image credit: Ralf Roletschek CC BY-SA 3.0)
Now the bottom bracket is out, give the threads a thorough cleaning with degreaser and wipe with a lint-free cloth. Check that the bearings aren't damaged - while it may seem an unnecessary expense to replace a bottom bracket that is otherwise fine, it's a lot less expensive than having stripped threads milled out of the bottom bracket shell before replacement with a custom-made threaded sleeve will be. If it can be disassembled, do so and clean the internal bearings in the same manner before regreasing them and putting the unit back together again. If it can't be disassembled, simply regrease the threads on both ends. Apply more grease to the bottom bracket shell's internal threads, then screw the bottom bracket back into the shell taking great care not to cross the threads - it should go in without any problems. Once in, screw in the plastic cup on the other side. Although the bottom bracket's moving parts are safely sealed within the units, the grease will prevent water getting into the frame by seeping through the threads.

It's not necessary to apply grease to square-tapered axles - in fact, some riders have found that doing so has allowed the cranks to slide too far onto the axle, causing the tips to splay and making it impossible to remove the cranks as a result. However, this is rare and other riders always grease them without problems. I do not; but this is largely because I never have done so - whether you do is up to you. In the case of splined axles, which feature a positive stop point and cranks that rely entirely on a bolt to keep them in place, grease is recommended. Some people insist that threadlock is essential on crank bolts to prevent them coming loose - however, I prefer to use grease and tighten them to the recommended tolerance, which has prevented them coming loose. If you have a torque wrench you can do this, if you don't then threadlock might be useful.

It's not possible to completely seal wheel bearings as doing so would impede rotation. However, most quality wheels are fitted with rubber guards that keep as much of the world outside where it belongs as is possible. As winter approaches, these should be checked for wear and tear.

Remove the wheels from the bike - the seals resemble rubber washers and can be seen pressed into the hub at either end. They can be pried out using the tip of a pointed knife or with a very thin flat screwdriver. At this point, you may as well strip down, clean and regrease the hub as this needs to be done at regular intervals and will help to ensure your bike survives the bad weather to come. Dismantle, lying all the components in a lint-free cloth in the same order they come off so you'll know which order to put them back on again, then clean all parts with dregreaser. Visually inspect all surfaces and bearings for signs of cracks, pits or other damage and replace any that are showing signs of wear, then reassemble using new grease - if you haven't previously stripped and rebuilt your particular make of hub or feel insufficiently familiar with its inner workings, it can be useful to search for diagrams online - most manufacturers make full blueprints and maintenance instructions, including recommended tolerances and other handy information, available in this way.

Hub components. Seals, if fitted, will be located over the bearing cones to keep dirt and moisture
away from the bearings.
(image credit: Keithonearth CC BY-SA 3.0)
Check the seals, which should be pliable and smooth. If they've begun to show signs of petrification such as cracks or other damage, it will be necessary to replace them. Bike shops may keep stock of those used in common hubs such as the Shimano range, but they may need to place a special order for other manufacturers - if they can't, search for the manufacturer online and see if you can buy direct. As a final resort, the keen-of-eye-and-hand might like to try hand-cutting a replacement from a piece of rubber - it's fiddly work, but can be done (you might also try asking a rubber stamp manufacturer for help - they're skilled at hand-cutting fine detail into rubber and might take the job on as a special project). Finally, apply some grease to the bearings, then reposition the seals.

Mudguards serve two purposes - they protect the bike from spray and salt, not just your clothes. However, if you use the bike purely for recreational rides or racing rather than for commuting and have carried out other winterproofing modifications, they become virtually redundant and do little other than add weight, so whether you choose to fit them or not is entirely up to you.

In the case of rigid bikes - such as road bikes and mountain bikes that don't have suspension - the standard design that covers a large section of wheel is best and the more wheel it covers the better it will protect. Nowadays, they tend to be made of flexible plastic rather than metal and even 180 degree coverage will add less weight than a cut-down metal guard of days gone by. To fit one, first check to see if your bike has the necessary eyelets brazed onto the frame and in the drop outs - these provide points for the metal rods that support the mudguard and prevent it from flapping around to fit onto. If you don't have them, you can use bolt-on brackets which are often supplied with the mudguards or can be purchased separately.

Crud RoadRacer Mk. 2 - the lightest and most attractive racer mudguard ever?
(image credit: Crud Products)
On racing bikes, which tend to have very little clearance between the tyres and frame, it can be difficult to find a mudguard that will fit - and even then, they frequently require modification to avoid fouling the tyre. Crud make an especially attractive and very lightweight mudguard called the RoadRacer Mk.2 which requires only 4mm of space.

Mudguards experience a very high degree of vibration and, as such, can rapidly become loose - and a loose mudguard support through the spokes is not good at all. To prevent this, use split washers, friction nuts, threadlock or a combination of all three to make sure everything stays nice and tight - superglue works as well as threadlock, and can be bought for as little as £1.

A Crud Catcher, designed to be fitted to the down tube
If the bike has suspension, full mudguards cannot be used as they need to be fastened to parts that move independently. Instead, fit the Crud Catcher type (proper Crud Catcher-branded ones cost about the same as the firm's many imitators, but Crud are a company run by cyclists for cyclists so it's worth the small extra expense to support them). The front guard is a single piece of plastic that fits onto the lower surface of the frame's down tube and is held in place either with screws in dedicated mounts similar to bidon cage mounts or with rubber bands. Their effectiveness is reasonable, doing a good job of catching dirt and water sprayed off the front wheel, but at high speed dirt tends to allow spray forward and blow back into the rider's face (as once happened to me with a big lump of mud containing a stone that cracked my tooth - serves me right for smiling when riding at high speed down a hill). Another type features an expansion device allowing the mudguard to be fitted to the lower end of the steerer tube, in between the forks - the main disadvantage here being that the gap between the front and rear sections, present to allow space for the fork, tends to be rather large and allows a lot of spray to get through. The most effective type is the one designed to be used specifically with a particular brand or model of suspension fork, as originally introduced by Marzocchi and since widely imitated. With these, the fork crown has a pair of threaded mounts allowing the mudguard - which is shaped so that when fitted it flows smoothly into the fork's lines and looks like an integral piece - to be screwed into place. I've been using one of these on my hardtail MTB with a Mazocchi Dirt Jumper fork for several years and it both look good and works extremely well. Check your fork online to see is a similar mudguard is available for it.

Mudguards designed for use with rear suspension are, unfortunately, somewhat of a compromise as it's not possible to position them closely enough to the wheel for them to do their job yet not get in the way of suspension travel. Crud were the first company to introduce a guard that fitted to a bracket bolted onto the seat pillar and these remain the best option - the longer and wider they are, the more crud they will catch.

As can be seen here, the drainage holes in the frame
frequently serve only to let dirt and water get in
Sealing The Frame
If you look closely at your frame - especially if it's steel - chances are you'll find some drainage holes. Look at the surfaces of the chain stays where the meet the bottom bracket shell and underneath the bottom bracket shell itself: not all bikes have them, but the majority do. These are intended to allow water that gets into the frame to get back out again but, if you've sealed the headset, seat tube and internal cable routing a already described, they're more likely to just let water in rather than out. So, we may as well seal them.

If you think there's any chance there may be moisture in the frame, first remove the forks, head set and seat pillar and spray some aerosol oil into the frame before hanging it upside down in a dry, warm room for a day or two - this will allow water to flow out or evaporate. Once done, simply plug the drainage holes using silicone sealant. The same can be done to seal bidon cage and mudguard mounts if you don't wish to use them.

It's also worth checking the frame for damage to the paintwork at this point. Scratches or other damage to carbon fibre frames need to be repaired by someone skilled in working with the material, as in time the fibre will fray and the frame will fail. Minor scratches in unpainted titanium frames can be polished away, as can those in aluminium frames. However, a scratch in the paint of a steel frame will very rapidly allow corrosion to begin. If you find one, lightly sand the affected area, then clean thoroughly with degreaser. Car parts shops sell small pots of "touch-up" paints in a huge variety of colours which are ideal for this purpose. Apply one thin coat, allow to dry, apply another coat, allow to dry and polish. If you can't find a matching paint, go to a shop that sells cosmetics - nail varnish comes in an even wider variety of colours and does the job just as well - you'll also be able to colourmatch your bike and your fingernails, which is nice.

Sealing Derailleurs
It was once possible to buy soft rubber devices that fitted over the front and rear derailleurs, protecting them from dirt and water and yet not impeding movement. These were produced either in the USA or for the US market, with sporadic consignments making their way to Europe where they would sometimes show up in bike shops. If you can find them, they're well worth fitting. If you know of a shop that has a supply, let us know.

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