FREQUENTLY ASKED QUESTIONS AND REGULAR ISSUES - I've tried to keep this concise but somethings just need explaining. I'm sure I've missed a few things and am constantly surprised by what can be achieved with no servicing, but the below is intended as a guide to some home solutions if in doubt book a service :) that's why I'm here
- Help - my disc brakes squeal?
- Were the disc's correctly bedded in? - This is the very first instant the brakes are used a series of controlled braking should be undertaken to "burnish" the rotor and ensure an even coating of brake pad material on the rotor or under heavy braking the disc may resonate. - Rotors will need to be polished back and pads faced off or replaced and the initial burnishing process completed
- Have the disc's been contaminated either through the liberal use of spray oils accidentally or through an unfortunate wet ride where a combination of road grease/debris/diesel etc has had enough of an effect -contamination squeal as a rule of experience becomes louder as more brake pressure is applied, very loud indeed, a complete lack of initial bite from the brake is further evidence. In some cases refacing the pads and thorough cleaning can solve the issue, however brake pads are porous and as such pull oil contamination through the entire pads meaning the squeal can quickly return -
- Are the rotors excessively worn, experience has taught me the middle of the brake tract wears down first, substantial grooves may be visible, pads may be wearing unevenly as a sign, chunks of pad material may be missing - Replace pads and rotor
- Has a seal failed and hydraulic fluid begun to contaminate the pads and rotor symptoms as above - Remove a pad and look for a tell tale ring of fluid on the pads back plate. Brake dependent and labour time allowing either caliper seals can be replace and system rebleed or replace entire caliper and rebleed
- Is it just a case of being wet and cold. Do the brakes stop when its nice and dry and sunny, say a nice ride in, in the morning but on a wet/damp ride home the squeal occurs? Brakes generate friction and friction generates heat and vibrations these if outside of normal operating tolerances can resonate as the horrible sound we hear - this is a tricky one, differing pad and rotor combinations, wheels manufacturers, tyre pressures, rider weight, speed all play influences roles in this,
- Help my Gears Tick, slip or just seem to shift on their own, I have to click up 2 and click down 1 for a shift
- Has the issue been from new or started soon there after: Its likely this is just cable tension, either initially poorly set or that the cable outer has settled in to the ferule's and caused the cable to slacken. Test shifting from highest gear(smallest cog at rear) 1 up, does a smooth shift occur - Find the cable adjuster barrel at end of outer either on rear mech or shifter and turn anti clockwise, half turns at a time and re-test - Once one shift is set All shifts are set, further issues means further problems
- I've done the above but it skips a shift in the middle of the cassette inconsistently now: if on the way up the cassette ( towards bigger cogs) this suggests an alignment issue with mech/dropout/cassette - have a look along the bike from behind the gear mech, does it look bent? It may require a new dropout/mech
- I've tried step one, I can get it to shift up but it wont come back down: This is usually Friction on the cable, modern internally routed bikes can be incredibly fussy some more than others (One day I will name and shame) Fancy coated inner cables can help, fresh outers makes a massive difference, in many cases outer is the route cause as the liner wears and adds friction.
- There is just an odd shift intermittently in the middle somewhere: This usually suggests something is bent out of alignment - back to looking down the bike from behind mech to check drop out, mech lower arm
- My gears tick in the high or low gear - This again points to alignment of a component or if all straight the limit screws. These H and L screws only effect the absolute limit the gear mech can move either inboard or outboard of the cycle, tiny quarter turns adjustments are called for
- My gears slip under heavy load, pulling away or climbing hills: If cable tension and shifting is all correct this points to a wear issue, either a worn damaged tooth/teeth on rear or front cogs causing the chain to jump or that the chain and or cogs have worn out, at times referred to as stretched. Chain measure devices can help here and show how worn things are, it is generally accepted to replace chains between .75 and 1 - this is millimeters of stretch (I know its not stretch - its flank wear on the pin, but stretch is easy to comprehend and understand) beyond this level of wear the chain begins to cut the cog teeth to what looks like a shark tooth or leaning over profile - this in itself can lead to chain suck if just a chain is replaced.
- Help My bike/BB ticks/clicks when I pedal, most notably as the pedal goes past 2 o'clock position
- Is there obvious play on the cranks suggesting the BB bearings have collapsed, or is the crank stiff to rotate suggesting a bearing has seized - replace unit, if not its the start of an elimination process
- Check the rear QR, this can be just for tightness but also with some cam designs removing the QR and cleaning lubricating the shaped cam lever seat, many times this can become stiff and give the impression of a very tight QR when in fact the compression load applied is not all that
- check the pedals, if possible test an alternative set of pedals - remove apply or refresh the grease,assembly compound on the axle threads and reassemble
- check the saddle rail clamp, if you have been bike fitted you may want to tape mark the rails to ensure getting back together exactly again. Clean and apply a fine swipe of grease to any metal to metal contact points or carbon assembly paste where carbon is
- check the seatpost in the frame. Due to winter weathers moisture does creep down the post/seat tube this can ultimately result in cold welding, don't go thinking carbon is inert, carbon will bind together in both alloy and carbon frames without paste to hold and protect
- check headset - is the compression cap tight, rock the bike for an aft with the front brake applied is there a knocking feel. are the bearings clean and OK
- Check chainring bolts for correct torque, and that of bolt on chainring spiders if applicable
- All above completed it still clicks. Then its likely to be the BB - Old school square taper and Octalink Shimano types if there is no actual play in the bearing I would remove the cartridge type unit clean both it and the BB threads and reassemble with grease or like compound. If Isis type unit this can be tried however new unit likely from experience. Pressfit types - These rely on a series of interference fits and thus machine tolerance. In many cases the effect of removal can be damaging ( not always but it hard to tell sometimes) Retaining compound 638 or the like can help in a metal to metal environment however if its a bare carbon shell then thats not always an option, a catalyst compound to be further used to ensure hardening. A Hope type BB or BB infinte/ Praxis where the BB cups pull up on themselves causing a compression fit as well as an interference is a good solution aided by the fact that future servicing should be pull and press of future bearing from the units without disturbing them - with a good puller.. BB30 direct fit with the circlip behind are a well documented ticker - however many times when I pull these apart the springclip/circlip and back of bearing are full of grease, as I first mentioned ticks and clicks are movement thus grease will only go so far or long before clicks return, a retaining compound is the engineering solution to pressfit cylindrical applications, this will harden in 24hours or so a you should be done. That said bikes are many differing component parts placed together and as such differing materials will have differing rates of expansion in both hot and cold environments - its not uncommon for ticks to suddenly occur on the first really hot days of the year or the first frosty morning.