Cycling UK Forum

I think cantis on touring bikes is what drove people to discs!

Frankly, cantis were rarely good. They replaced big centre-pulls on tourers, being rather less flexy, and were essential on early MTBs to fit around fat tyres. Their heyday was quite short-lived; from the 80s to the mid-90s, when V-brakes took over on MTBs. They lumbered on for tourers with dropped bars for much longer.

Low-profile cantis on flat bars work quite well with the big original 4-finger levers, where a lot of the mechanical advantage comes from the length of the lever and it doesn't easily run out of travel. Late 80s DX levers and DX/XT cantis are pretty good stoppers. They are less successful with 2-finger levers or drop bar levers. Playing with the geometry (maximum pad extension until just before they start squealing, straddle wire just off the tyre) helps, as does pad material, but they're always compromised. Ok in the dry, marginal in the wet, really bad in the wet with a heavy load on.

Plain gauge spokes have three marginal advantages:

- Cheaper
- Easier to build with
- If one breaks, the wheel doesn't go as far out of true

In every other respect, butted spokes are better, as they are just as strong (spokes rarely breakin the middle), lighter and more resilient.

(Insert urban legend about someone who used vaseline on the plunger and exploded the pump by compression-ignition).

sjs wrote: ↑16 Nov 2024, 1:07pm

pjclinch wrote: ↑21 Oct 2014, 3:11pm

AMC wrote:, the old two wheeler cyclist gets on trike without realising trick - don't I know it too!

It's worse than that, you climb aboard and, somehow realising you have 3 wheels, you say, "I remember all those things I read about the steering being different! I'm a canny chap though, and I'll not try to take the corners by leaning, but by steering the bars alone", and then you ride along a straight road and drift down the camber in to the kerb as if completely incapable of doing anything about it...

Or, errr, so I hear...

Pete.

I had a go on a trike at the cycle museum in Llandrindod Wells a few years ago. Couldn't ride it competently even on a perfectly flat interior floor. Succeeded only in becoming (even more of) an object of ridicule to the rest of my family.

I tried a RWD recumbent trike around a field once. Hilariously easy to wheelspin, as there is really very little weight on each rear wheel (being split between two of them) and only one is normally driven.

For 700c wheels, that fork offset is pretty standard for that head angle. It will handle like a racing bike, i.e. with significant lean steer, fine for an unladen or lightly-laden bike.

If you were going camping on it, it would want a lot more offset to neutralise the lean steer and stop it wagging its tail when you pedal standing up.

They're lower power (under 2W) so weren't any good with the typical 2.4W or 3W halogen lamps in latter incandescent dynamo lights, but they are fine with most LED lights.

Most LED lights can't use the full 3W from a typical dynamo. I recently fitted an old Schmidt E6 light with the Reflectalite 1W LED. The voltage regulator (basically two zener diodes that dump excess voltage to a large-ish resistor) gets quite warm. I assume most cheaper LED lights have a similar wasteful regulator, unless they have a high power LED chip with appropriate heatsinking. LEDs have a higher luminous efficacy than halogen lamps but the waste heat stays on the chip and has to be conducted away somehow, instead of being mostly radiated as IR.

Just find an old steel frame with decent tubing and build one up. Fixies are supposed to be built, not bought.

I'm always fascinated by Orla's choice of footwear, often completely at odds with the rest of her wardrobe

They're not really designed for bike use as the rubber seal is to exclude airborne dust and grit, not water. Having said that, they hold up pretty well and you effectively have a brand new hub when you change the bearings.

If you have rim brakes, fine aluminium dust is completely normal, and is just the rims wearing down. In dry conditions, this might take decades, but I have taken rims to the wear limit in 18 months through commuting in all weathers on muddy lanes. Some mountain bikers used to destroy rims even faster than that, which is why they adopted disc brakes first. It mainly depends on how much abrasive crud gets thrown at the rims, and rear rims wear fastest as they're right in the firing line from the front tyre.

If the rim had been touching tarmac, you'd see really severe damage.

Brucey wrote: ↑24 Oct 2024, 7:28pm

mister_ed wrote: ↑24 Oct 2024, 9:06am... the head tube is bigger than expected....

the most common size for threaded headsets is 30.2mm ID for the head tube, but there are some that use a 30.0mm ID head tube. I think it is OK to use a little adhesive (eg. epoxy resin) to hold loose-fitting cups in place. The first time I did this, I thought it was probably a bodge. However, being almost stress-free, I now consider it to be an improvement. In fact I consider most interference fits to be fairly barbaric.

A beer can shim is better, as it doesn't affect removability.

If a headset won't stay tight, it often means the head tube and fork crown seat want facing.

Not much difference for 135mm spacing, unless you want to use original thumbshifters, which are 7 speed and only sort of work on 8 speed, whatever you may have read.

For road spacing there is a bigger difference, since frames are 126mm for 7 speed and 130mm for 8 speed!

I'm not sure I want to know why you still own four cracked aluminium bikes

hamster wrote: ↑22 Oct 2024, 3:03pm

rjb wrote: ↑22 Oct 2024, 2:36pm I'd lusted after a titanium frame but after reading about multiple failures of them I've gone for steel or alluminium tubing.

Fair enough with steel with a potentially infinite fatigue life, but Aluminium inherently has a finite fatigue life. So it will eventually crack after so many stress cycles.
So you are saying that you were so worried about a Ti frame possibly cracking that you decided to buy a frame that definitely will crack.

Nowt as strange as folks.

Badly made Ti frames with poor control of welding conditions are likely to fail. So are badly brazed steel frames. I loved my (early) Litespeed - which is still going strong. Later it seems that they tried to keep pace with the low weight of carbon frames and underbuilt them, leading to cracking.

I don't think the material.matters as much as the quality of construction, and it's also likely that steel or titanium frames sometimes exceed the local fatigue limit (which can be severely compromised by an overheated weld) during riding on bad roads.

Aluminium frames, 1980s Alan and Vitus bikes excluded, are oversized to minimise bending and I've seen fewer reports of those cracking than anything else. Ok, early Cannondales sometimes had the head tube fall off, but some of the welding on those was atrocious, apparently using filler where the man with the smoothing file had gone right through and made a hole.

Obviously the thinner the tubing, the more likely it is that a crack will propagate, whereas your average Apollo gaspiper is very tough indeed.