the 'there's no such thing as a stupid question' bike maintenance thread

Leprechaun77

Type 17 wrote: »

Take a look at the current tyre sidewall and, beside the 24 x 1 marking, there will be other numbers in the format xx-xxx - this is the ETRTO measurement (more details here, if you're want the whole story).

This is the bike/tyre/rim manufacturers' measurement and is the definitive size, because all of the other sizes are a historical mish-mash of metric, imperial, French, British, American, japanese and other measurements.

Post the ETRTO size and we can work out if wider tyres are available and/or suitable.

Thanks for that. The numbers are 23-540.

Type 17

Leprechaun77 wrote: »

Thanks for that. The numbers are 23-540.

Ok, the 540 is the rim diameter in mm, so any tyre you want must have 540 (or 541, which I did see on a search) in the ETRTO size.

The other number is the tyre width in mm. The 23 on the current tyres is almost the narrowest size available, so if you can find tyres with say 25, 28 or even 30 (if the frame/fork/brakes will take it) in the size, then you'll be onto a winner, but if the three-digit number isn't 540, then they're not going to fit.

PS: There isn't a huge gain to be had in grip by fitting a tyre that's a few mm wider, but a wider tyre will be a bit more comfortable, and is less likely to suffer from pinch-flat punctures.

07Lapierre

Anyone built up a frame / integrated stem and handlebar recently and fitted internal mechanical shifter cables? I’m told it can be done, but you have to use a full length outer cable housing from the shifter all the way down to the front and rear derailleurs? I’m concerned it won’t work due to the sharp turns /in direct cable routing combined with the increase in friction? Any tips/recommendations? ( besides upgrading to di2 that is! )

woody33

Hi, does this look like a cup and cone or a sealed bearing? (A bit grubby, I know.) Thanks...

Type 17

Cup-and-cone. The brown tint of the grease on the silver dust cover is a sign that the grease inside is (also) dried/drying up. Time for a service...

woody33

I have just checked, it seems to be dried grease all right and not corrosion as i thought. Would a dribble of oil in the gap do any good? At the back I have already failed to remove the freewheel myself (blush), having bought and adapted various tools, so I could probably only service the non-drive side. Hmm I have a large tub of Castrol LM grease which should do.

Type 17

Some dribble-oil (not the thin, aerosol types) would help - grease is basically oil in thickening agents to slow its drying up and/or running out of the required place, so some oil is better than none (obviously, grease is more complex than that, and there are multiple types, to take account of varying loads, temperatures, moisture levels, etc).

Freewheels are virtually impossible to remove without the right tools - the action of pedalling tightens it onto the hub, so they're almost 100Nm tight.

You should service the bearings on the drive side, as they're the ones that take all the load when you pedal, and dried grease will kill them quickly enough (pitted cup and cone). Castrol LM (lithium-based) would be fine, once you get the freewheel off.

woody33

Previously I had to go to my LBS to get a spoke replaced on the drive side, I might try some chain oil dripped into that side, and re grease the others. The wheels seem to spin ok without wobbling at the moment, but good to know what type bearings they are, Thanks again.

tomasrojo

If it's a screw-on freewheel you only need one specialised tool: a nut that slots into the splines that surrond the axle. Then you need a ring spanner that fits that nut, and an awful lot of force to unscrew the freewheel. I used to use my legs to get enough force. It usually came free very suddenly but I managed to never injure myself.

woody33

Finding the correct tool was the issue, I bought one, wrong, bought another, wrong again, filed it down, still no go. Drat. Possibly should get a new cassette with the right tool, or a wheel with a free hub, but set up for v-brake. Anyway, I'm still on the road, within the 5 kilometres, obvs. Thanks again.

07Lapierre

tomasrojo wrote: »

If it's a screw-on freewheel you only need one specialised tool: a nut that slots into the splines that surrond the axle. Then you need a ring spanner that fits that nut, and an awful lot of force to unscrew the freewheel. I used to use my legs to get enough force. It usually came free very suddenly but I managed to never injure myself.

You also need a chain whip.

cython

07Lapierre wrote: »

You also need a chain whip.

Not to remove a screw on freewheel (as opposed to taking a cassette off a freehub).

tomasrojo

Yeah, based on what's been said, it's an old-fashioned freewheel which screws onto the hub body like a bottle top screws onto a bottle, rather than a freehub.

07Lapierre

Ok, my mistake.

crosstownk

cython wrote: »

Not to remove a screw on freewheel (as opposed to taking a cassette off a freehub).

Unrelated but ...... I vaguely remember needing two chain whips to remove the freewheel on a 7 speed Shimano 600 Select hub back in the 1980s. Maybe the smallest cog was threaded? Am I right or just old and confused?

8valve

crosstownk wrote: »

Unrelated but ...... I vaguely remember needing two chain whips to remove the freewheel on a 7 speed Shimano 600 Select hub back in the 1980s. Maybe the smallest cog was threaded? Am I right or just old and confused?

I think that was the system on the old shimano uniglide freehubs, precursor to the current hyperglide cassettes, which is the design still in use.


the giveaway was the couple of mm of thread on the outside of the freehub body for screwing on the smallest sprockets.


I think suntour had something similar?

cython

crosstownk wrote: »

Unrelated but ...... I vaguely remember needing two chain whips to remove the freewheel on a 7 speed Shimano 600 Select hub back in the 1980s. Maybe the smallest cog was threaded? Am I right or just old and confused?

Before my time, to be honest! I'm just basing my comment off how it works removing freewheels with a remover tool like https://www.parktool.com/product/freewheel-remover-fr-1-3

However, as another poster has said, you may be referring to the uniglide cassettes, where the smallest sprocket double jobbed for the lockring in the current hyberglide system:

https://www.youtube.com/watch?v=1zWYLb2RMPA

Type 17

Yes, Uniglide (and previous offerings from Shimano and others) gave the opportunity to configure your rear cluster to whatever sizes you wanted because each sprocket (sold separately at your LBS) worked in almost any position in the setup. I remember buying one new sprocket after changing a chain, because the old chain had caused a bit too much wear on one (fourth of the six). I still have six-speed Dura-Ace Uniglide on a 70's road bike I have - I found that the previous owner had got around the skipping issue with a new chain by turning the first five sprockets around to use the other side of the teeth (an old trick, no longer possible with Hyperglide).

While Hyperglide removed those flexibilities, it allows for quicker, smoother shifting, and with continuous pedal pressure* because each sprocket's profiles and side-stampings/cutouts are related to its position in the cluster, and to the other sprockets beside it.

*On older stuff, if you didn't ease up the pressure when shifting, the chain could slip and/or skate over the tops of the teeth, causing a fall or chain/sprocket damage. Especially tricky when on a steep climb.

tomasrojo

8valve wrote: »

I think that was the system on the old shimano uniglide freehubs, precursor to the current hyperglide cassettes, which is the design still in use.


the giveaway was the couple of mm of thread on the outside of the freehub body for screwing on the smallest sprockets.

Sounds very plausible:

The smallest sprocket on a Uniglide cassette was not splined, it was threaded. The threads of this sprocket would hold everything else together. Dura-Ace Freehubs used a different, smaller thread, which worked only with Dura-Ace threaded sprockets.

https://sheldonbrown.com/k7.html#uniglide

crosstownk

Type 17 wrote: »

Yes, Uniglide (and previous offerings from Shimano and others) gave the opportunity to configure your rear cluster to whatever sizes you wanted because each sprocket (sold separately at your LBS) worked in almost any position in the setup.

Yep. Uniglide it was. I vaguely remember being able to change individual sprockets alright.

padyjoe

I have a KMC X9-silver, Pedros II showing around 0.5% wear nearing 3k kms. Is it ok to run it down to 0.75%? This is on a new outer chainring and cassette. The jockey wheels have 27k kms on them, time to change I wonder?

LollipopJimmy

padyjoe wrote: »

I have a KMC X9-silver, Pedros II showing around 0.5% wear nearing 3k kms. Is it ok to run it down to 0.75%? This is on a new outer chainring and cassette. The jockey wheels have 27k kms on them, time to change I wonder?

I wouldnt run an old chain on a new cassette, you're just going to wear the cassette much quicker.

Jockey wheels are cheap, id be inclined to change them also at that mileage

padyjoe

LollipopJimmy wrote: »

I wouldnt run an old chain on a new cassette

It's an all new set, well it was 3k ago, when I changed every component: chain, cassette, chainring. Considering the below explained, better off not 'stretching' to .75%?
I don't go OCD on cleaning the chain but I wipe and lube it on a regular basis.
The chain is stressed above average I reckon: ca. 105 kg total, 36 spoke wheel and average 27-30 km/h.
Thank you!

Type 17

Think of it this way: if you run the chain down to .75%, you're also running the cassette & rings down to .75%, so they will drag a new chain down to their wear-level that bit quicker.

If you keep changing the chains at .5 or .6%, the cass/rings will only ever be at the that level and the extra few km you "lost" off the end of each chain (by not going past .5% or so) will add up to less than one chain, which is far cheaper than a cassette and big ring.

padyjoe

Well, this needs no further explanation. And no excuse either as I have a spare chain in my drawer. KMC threw in a 17k number for a roadbike in their leaflet, I know it's extreme distance with a minimal abuse. I think, I should be proud of myself being able to kill the chain in 3k. Or I'm still a fat fúkker! :-DDD

LollipopJimmy

Sorry I had read your post as you had just fit the cassette and chainring now. Answered above anyway by Type17

padyjoe

No, it's my mistake, I've never mentioned the chain condition, it wasn't clear.

Thanks for your input!

Away With The Fairies

I got home ok yesterday. I didn't cycle over anything sharp, that I know of. Then this morning, I woke up with a flat tyre.

I done a google search and cold weather can cause flat tyres! How likely is cold weather the cause? Have the bike almost a year and no bother with it until the flat tyre this morning.

Type 17

Most likely a slow puncture, picked up on your way home, but not noticeable until later on.

The kind of cold weather that causes punctures is the kind you get in Siberia, Northern Canada, etc.

Away With The Fairies

Type 17 wrote: »

Most likely a slow puncture, picked up on your way home, but not noticeable until later on.

The kind of cold weather that causes punctures is the kind you get in Siberia, Northern Canada, etc.

Thanks, have to get this fixed.