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

Type 17

I'm guessing that, with the worldwide demand for new bikes, there is a resulting shortage of components for the spares/groupset markets.

This also happened a few years ago in the supplies of low-end gear hubs (eg: Shimano Nexus 3-speed) and hub brakes/generators - the dockless bike hire market was taking them all.

8valve

CantGetNoSleep wrote: »

Tbh there seems to be a shortage of disc components / groupsets at the moment - both new and second hand. I'm trying to sell a frameset but any of the buyers pull out when they realise they can't find a 105 disc groupset in stock anywhere, and any second hand groupsets seem to sell in minutes

Massive shortage of groupsets worldwide; Shimano think the current blip will only last about 12-18months, so are quite happy to max out current facilities production capabilities and ride out the storm, rather than build another factory to meet short term demand.


Retailers can't get groupsets, either; in work, I've been building up framesets over the past couple of months with any combintion of mixed Sora/Tiagra/105/Ultegra groups, and adding a set of Mavic wheels, just so bikes can be completed and sold.

a148pro

Ok this is really annoying me now - I've had I think 1 puncture in the last two years, but have lost three separate presta tubes when the screw bit breaks when pumping it up. What am I doing wrong? I usually screw it open a bit, toot out some air and then put on the pump. I don't think I'm unscrewing to too far, unless I'm supposed to?

Its often a struggle to get the pump on, you have to push it down quite hard to get it to lock. Maybe a cheap pump putting too much pressure on the valve?

I have to say I find presta valves just awful, they're finickey and hard to fit a pump onto. Can you get Schraeder valves for road bike tyres / wheels? What's bad about them?

Type 17

Sounds like a cheap pump, and you're wobbling the head around too much whilst attaching or pumping, which bends the thin stem. If you're pumping at home regularly to top up the pressure (which everyone should be), get a track-pump, which has a long hose so there's no side-load on the valve when you're pumping. If you're pumping when out (after a puncture) and using a mini-pump (one where the pump body fastens directly onto the valve), wrap your fingers around the valve-end of the pump and the tyre to keep everything steady, and keep the other end of the pump in line, to avoid straining the valve.

You should open the valve all the way - the top of the thin stem is stamped, so you can't lose the part you unscrew.

Presta valves exist for the narrower rims of racing bikes - if the valve-hole was big enough for a Schraeder valve, the rim would be weakened enough to fail.

a148pro

Pretty comprehensive Type 17, thanks, no excuses now. I wasn't opening it the full way as I figured the longer it was extended out the more pressure out on it.

Someone best recommend me a good track pump so? I mean I have a track pump in the sense that it sits on the ground but my recollection is it was cheap. The hose isn't that long so it probably has some lateral pressure as you use it. And it is quite hard to get on so I'm obviously pushing quite hard on the valve to get it on, and pump them before more or less every ride

07Lapierre

Joeblow track pumps are good.

secman

Noticed a slight rattle in the headset on my spin today, the part of the brain that deals with mechanical stuff just never worked for me . So did a quick search on YouTube, got out the necessary tools and delighted to say it's sorted, not over tightened either, steering nice and free and just a gentle bounce like in the video

cletus

Nothing beats the feeling of doing a job yourself. Fair play

Mr. Cats

I’m installing di2 into a frame build & looking for a recommendation how to stick the wire that’s going through bottom bracket shell onto frame? I want to fix it above the bb I think - do people just use gorilla tape? Also, does the centre part of bb rotate or just the bearings? I think it’s just bearings. It’s a bb865 with shimano hollow tech.

Type 17

No issue with that BB rotating - the hollowtech spindle is inside the (non-rotating) dust/moisture shield, so no danger of the cable being entangled, but do have it carefully taped for BB insertion and to avoid rattles in the future - shouldn't matter if you go above or below the BB, but there's more surface to stick onto on the bottom, and you're not fighting gravity. The biggest issue will be to avoid the cables rattling (use the Shimano plastic clips).

Mr. Cats

Type 17 wrote: »

No issue with that BB rotating - the hollowtech spindle is inside the (non-rotating) dust/moisture shield, so no danger of the cable being entangled, but do have it carefully taped for BB insertion and to avoid rattles in the future - shouldn't matter if you go above or below the BB, but there's more surface to stick onto on the bottom, and you're not fighting gravity. The biggest issue will be to avoid the cables rattling (use the Shimano plastic clips).

Makes sense. Will do under bb then. Thanks a lot!

stop

Was fixing a puncture the other day (first time doing it myself, 12 years cycling ), after replacing the rear wheel, my disc brake seems slow to respond (spongy?), I have to really pull the lever to get any result from it.
Could I somehow have damaged the brake/disc when putting the wheel back on?

Type 17

The disc may not be centred evenly in the drop-outs, and therefore between the pads. Check if the wheel is a little crooked compared to before the puncture - loosen the skewer or thru-axle and jiggle the wheel and then lean down on the saddle whilst re-tightening the wheel.

Pump the brake a few times to re-settle things, and see if is better.

If not, check if the calliper is centred on the disc - re-centre it if not.

Other things to check are the seating of the pads and their spring, and whether or not one piston is stuck/starting to stick.

JMcL

8valve wrote: »

Any feedback on the TRP HY/RD calipers?


Considering a set for the next frankenbike.

I have them on a Genesis Croix de Fer and find them grand. I don't have any full hydraulic setup to compare them to (though this may change soon....), but they're much more confidence inspiring that rim brakes especially in wet weather. The original pads weren't great (no idea what they were) and I've replaced them since with a set of no-name pads from Amazon bought on a whim which have in truth been excellent for the price

Weepsie

New headset bearing on my croix de fer. I had cleaned the old one as best I could and tightened back up but still a bit of play and wasn't brilliant when braking.

Night and day now and superstar components sealed bearings we're about half the price too

silverharp

more a settings/app question, I have a standard lunchtime mid week route and I want a simple way of pacing it to that I can beat the previous week's time, the route isnt flat so an overall average wont be of much use. If its a feature in a mobile app what is it called? practically what is more useful, screen, earpiece if its a common feature?

Type 17

Have a look at Cyclemeter for your phone (iOS at least, not sure if it's on Android too)

You can set up routes and set voices to tell you your av speed, time, etc per km or per x-hundred meters if you like.

Fancy version costs €10/year (export to Strava, etc), but the free version can do the pacing thing. (I pay the €10 - I find it better/more stable than Strava when out on the road - I only look at Strava on the laptop)

Zen0

Probably not the answer you’re looking for, but most of the Garmin bike computers let you “race” yourself over a route you have previously completed, showing you how far ahead or behind you are compared to your previous best time. I’m not aware of any apps that do that.

cletus

I know in Garmin connect you can trim an activity you forgot to press stop onve you get home, but is there any way to cut out the dead time if you forgot to pause the ride when stopped for coffee etc?

Morris Garren

My question is related to gear ratios: is a 54t big ring workable with 36t inside ring? I was once told that the jump was 'too big'- whatever that means. It is a double chainset

magicbastarder

generally road oriented chainsets come in three sizes - 53/39, 52/36, and 50/34. i suspect an 18 tooth difference might be outside tolerances for a front derailleur, and possibly RD too?

Morris Garren

magicbastarder wrote: »

generally road oriented chainsets come in three sizes - 53/39, 52/36, and 50/34. i suspect an 18 tooth difference might be outside tolerances for a front derailleur, and possibly RD too?

Thanks-- I am interested in knowing if there is a maximum 'jump' in terms of teeth on a standard front Derailleur. Looks like it is 16?

keane2097

cletus wrote: »

I know in Garmin connect you can trim an activity you forgot to press stop onve you get home, but is there any way to cut out the dead time if you forgot to pause the ride when stopped for coffee etc?

You can edit the GPX file with a text editor quite easily, but for future rides you can also tell the garmin to autopause if you're under say 5kph which works fairly well

dermabrasion

Mechanical Disk brake question:
The movable (single outer) piston has come loose within the cavity of the brake housing. I can't seem to get it back into where I think it comes from. I don't know how it is fixed to the spring-loaded lever arm. I don't think it is treaded as I've tried to screw it back in.
thoughts or knowledge welcome
D

MojoMaker

Morris Garren wrote: »

Thanks-- I am interested in knowing if there is a maximum 'jump' in terms of teeth on a standard front Derailleur. Looks like it is 16?

Very hard to get a straight answer on this. The general feeling appears to be that Shimano are quite conservative in their official line around max 16T jump. Have heard of at least one chap on here who said he's running a 52/34 without issues, but no detail with that.

Among other things with a larger gap you're risking chain drop from outer to inner I guess? I'm sure the chain needs a tweak, but no idea on RD settings. Anything else?

Type 17

While you might have the cage nice and close to the teeth of the big ring, when the chain drops to the small ring, and the RD is on a relatively small sprocket you may find the chain fouls on the cage - it depends on the FD model and what type of bike it's meant for.

Look at how far around the rings the FD cage extends - ones for triples and older MTBs are very deep (top to bottom) and will take any ring-difference, but older FDs (eg:for 42/52) are very shallow and therefore limited:

Planet X

Never had a MTB before.


OK.......First "kinda" mountain bike. Kona Unit. New.

Bought new tyres, Schwalbe Marathon Mondial 28 x 2" to replace, what came on the bike, WTB Ranger TCS 2.6"

Struggling. Tyres off, new Schwalbes on but cannot seat anything. I think this is because the inner tubes in the WTB's state, 2.5" to 3.0".
I have new matching tubes.......in work. Didn't think I'd need them.

So, is it the 2.5" to 3.0" inner tubes that won't let me seat the 2" tyres?
Think so.

wheelo01

Quick question, I have hydraulic disk brakes on my road bike, should i buy resin or steel replacement pads, it's only leisure/fitness cycling (max70km (occasional 100)) i do.

Shimano BR-R7070 brakes

Cheers

magicbastarder

what's the difference in price between the options?
i wouldn't worry so much as to their 'everyday' use, i'd be more concerned with maintenance and confidence in them. you want to judge them by how good they are when you *need* them.

CramCycle

Either will do the job, I would just pick the ones that fit and are available.