front hub service

This is a quick service job on a 20mm DMR Revolver through hub. The bearings are sealed so replacement is required when you hub starts to sing to you on a quick downhill section.

Do not assume that your local bike shop will hold stock but the manufacturer’s site  will normally state the size and some show simple instructions for changing the bearings. The main internet suppliers will reply to a query about size and even offer you a part code.

If you are really keen then there are some sites which delve into bearing nomenclature and the delights of hoop stress and radial stress. Please allow me to bore you with this individually on a ride.

Hub showing the outer cup but with through axle removed

bearing in hub

gently tap out inner axle and bearing on lower side

carefully tap out second bearing

tap in new bearings and axle using correct sized socket to prevent damage

pressing bearings fully home

I fitted the external cups and gently pressed the bearings fully home. The manufacturers instructions suggested using the socket and hammer method but this seemed harsh. I did consider using a drill press or a vice but the correct tool is a bearing press. I used this ratchet clamp as a substitute.

Everything was cleaned and regreased at the appropriate points.

A quick service job that is less difficult than cup and cone as all the worn bits get replaced as a unit.

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jobs,jobs,jobs

Spring was sprung in a flurry of snow and rain, summer seems to have arrived immediately, and all the maintenance jobs that have built up over the winter need to be completed before long summer days begin to shorten.

Some bikes may need virtual rebuilding of the transmission, forks, brakes, wheels and perhaps all the bearings and bushes in that clever linkage. Got a singlespeed, rigid forked hardtail and feeling smug? You still have a headset, bottom bracket, cables, and brakes. Obviously both hubs need servicing, wheels that need to be trued and maybe that maintenance free frame needs all the protective tape and patches replaced.

Forks seem to last almost forever nowadays until they fail and you fall off into a bomb hole at Pitch Hill. Some forks are less straightforward than others are when it comes to servicing and 36 Vanillas seems to need more than most. After checking component prices and even a tool or two perhaps consider a specialist like Mojo or TFShox. My Vanillas came back from Mojo with new lower legs, fully serviced and all for £100. So think about whether the service cost is reasonable especially considering the benefit of the warranty guarantee.

Rear shocks can seem perfect but when did you last even check the air pressure or the sag. Many shocks are an easy lubrication task with various guides in the bike magazines or online.

Brakes have improved dramatically over the last few years with all the latest models offering great stopping power and almost forget it reliability. However, mud, grit, rain, and damp storage are the perfect combination to encourage corrosion in even the most resistant alloys. Try removing your pads and pushing the pistons in your brake callipers fully home. You might have to allow some fluid release from the reservoir but also allows you to check carefully for signs of corrosion due to even the smallest of leaks and like your car they need re-bled occasionally or even the whole fluid changed. If you are lucky, you might just need to remove the pads and clean the springs before refitting. If it needs a little more then perhaps your local bike shop would appreciate the work.

Bottom brackets are easy to remove and now do not need complete rebuilding down to the smallest parts after a wet ride or two but a strip and re-grease will delay the time until replacement is required.
Headsets tend to work uncomplainingly but even the best units appreciate a wipe and some new grease. Cheaper models would be delighted with some new bearings too.

Transmissions are complex mechanisms that we want to be light, stiff, and smooth as silk when changing gear up a hill, in the mud under load. That chain that has had a bit of a clean and oil over the winter needs a close check for twisted links and for wear in its length. Use a chain gauge or a ruler to check the length for wear. Cassettes wear too so squint at all the rings. If the teeth look hooked then it needs replacement. While working at the rear hub take off the freehub and service it too. Replacement bearings and even axles are available and save loads of effort turning a worn hub up a hill.

Cables seem to look perfect even at the end of their life so if you want to check them cut off the cable end and pull them out of all the cable outers. If it is not almost perfect, new cables are cheap and easy to replace and it forces you to reset the indexing.

Front hubs require a clean and re-grease and bearings replaced occasionally.
Other parts seem maintenance free but check saddle rails for straightness and maybe a proper clean underneath and on top.

The seat post needs the clamp and bolt cleaned and regreased and the post itself checked for cracks.

 

Talc on tubes

talc-bottle.jpg

A long time ago, in a land of my youth, everyone learned to repair punctures in fragile tubes. Tyre levers and cutlery handles were used to pull off a bead and the ritual of partially inflating a tyre and immersing it in the sink to find the telltale bubbles were familiar to all. However the march of technology has taken us to tubeless self sealing tyres and the affair with changing tubes has cooled.

However I still use tubes, albeit gunk filled, and can feel the difference when the tyre and tube stick together so I periodically invest in a large plastic bottle of talcum powder and use liberally over the tube before fitting. It is important that the tyre well is clean and dry and a small amount is squirted inside the tyre but when fitted the tube and tyre distort independently and it feels softer or more compliant.I have ridden without talcum on my tyres but found that the gunk spreads further after a puncture and the bead can end up stuck to the rim.Instead apply a foot’s worth of talcum and feel the difference. Obviously when forced to change a tube at the farmyard gate the smell of the occupants will be completely masked by the perfume, your riding buddies will stay to help and you will immediately find the thorn.The last bit is not guaranteed.