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

54and56

magicbastarder wrote: »

what sort of cleaning did you try on the pads? the rotors clean easily, pads require a tiny bit more work.

I didn't try cleaning the pads myself. LBS said the pads were contaminated and transferring oil to the rotors leaving a black rim mark on the rotors which I could see. They said replacing the pads and cleaning the rotors may solve the problem in the short term but the rotors would never be fully clear of the contaminant so would likely pick up new contaminant and the cycle would just continue.

magicbastarder

hmm. i wouldn't be so quick to write them off like that. i've successfully cleaned pads and rotors before.
obviously, the situation might be different with yours.

Type 17

The problem is that if the contaminated brakes are still used for any period of time, the discs lose their (microscopic) rough texture from being polished by the contaminated pads. Once they're this smooth (glazed), it's very hard to bring them back, even with new pads and treatments with sandpaper or an oilstone.

Thicker discs on motor vehicles used to be de-glazed by re-surfacing on a lathe, but these days this is probably only done on especially rare/expensive discs with lots of life left in them.

54and56

Type 17 wrote: »

The problem is that if the contaminated brakes are still used for any period of time, the discs lose their (microscopic) rough texture from being polished by the contaminated pads. Once they're this smooth (glazed), it's very hard to bring them back, even with new pads and treatments with sandpaper or an oilstone.

I think this is what the LBS were getting at. The rotor's have been damaged so cleaning them and/or changing the pads alone isn't going to restore their operating performance.

tomasrojo

tomasrojo wrote: »

Think this might be the correct tool.

https://hollandbikeshop.com/en-gb/bicycle-tools-maintenance/bicycle-tools/bicycle-hub-tools/shimano-key-hub-dynamo-tl-dh20/?country_id=260

Pretty pricey. I might have to make something after all. The video I linked in that post, and another post on YouTube, seem to have used 8mm bolts filed to be square embedded in some metal as a wrench.

Just for posterity: that is the correct tool. Mentions here that it's compatible with the following dynamo hubs:
DH-2R30/2R35/3R30/3R35 DH-C6000-3R/2R/1R DH-F703

And mine is the DH-C6000-2R.

Still thinking about making the tool instead. It's the type of part you only have to install once and remove once, so damage to the crenellations wouldn't be that important, if I made a two-pin tool, as you'd always have more diametrically opposed crenellations to attack next.

€60.50 is cheapest I've seen.

EDIT: Given the economic concept of opportunity cost and how many other things I have to do right now, I suspect I'm going to buy the €60.50 one.

CramCycle

For taking it off, I can't help but feel a flat head screwdriver and tapping at various points with it held in place should do the job, if stuck to hard, a large socket, drilled in a few places and short nuts and bolts through it might also do the job.

tomasrojo

CramCycle wrote: »

For taking it off, I can't help but feel a flat head screwdriver and tapping at various points with it held in place should do the job, if stuck to hard, a large socket, drilled in a few places and short nuts and bolts through it might also do the job.

Yeah, I used to use a hammer and chisel to get the notched lockring off old-fashioned bottom brackets, though I did buy the right tool in the end.

From one YT video, it does look as if the lockring(*) for the hub internal assembly would be on fairly tight. The other YT video made it look as it it was easy to get off with the homemade tool, but I suspect he'd already had a dry run before videoing. It was suspiciously easy to get it off: no exertion at all; while in the other YT video I watched, the guy had to turn quite hard, and he damaged some of the crenellations.

(How do you mean "a large socket"? The guys in the videos used various types of metal, drilled holes and put bolts through, and at least one of the guys filed the bolts to have a square profile.)

(*)EDIT: Not a lockring; the crenellated perimeter is an integral part of the dynamo body, so I mean the internal assembly might be screwed in place quite tight.

CramCycle

tomasrojo wrote: »

(How do you mean "a large socket"? The guys in the videos used various types of metal, drilled holes and put bolts through, and at least one of the guys filed the bolts to have a square profile.)

So I have a socket wrench in work, if you had a socket that fits just inside, you could then drill holes into it to have small nuts and bolts to interface with the. I think this would be awkward but doable. The other option which might work better is a larger socket that fits just inside the outer circumference and using a dremel cut out notches so it can slide in.

In fact, if you could live without the wheel for a few hours I could collect and see if any of my old sockets in work fit and could I make one for under a tenner. or PM me the measurements and I can check on Monday.

tomasrojo

CramCycle wrote: »

So I have a socket wrench in work, if you had a socket that fits just inside, you could then drill holes into it to have small nuts and bolts to interface with the. I think this would be awkward but doable. The other option which might work better is a larger socket that fits just inside the outer circumference and using a dremel cut out notches so it can slide in.

In fact, if you could live without the wheel for a few hours I could collect and see if any of my old sockets in work fit and could I make one for under a tenner. or PM me the measurements and I can check on Monday.

That's very decent of you. I'll have a think about this very kind offer!

You do need a gap in the circle of whatever is interfacing with the crenellations, because the connectors for the wires and spade coming down from the front light would get in the way of a complete circle, which is why the Shimano tool is like a C in profile, and why one homemade tool has this cutout:


... and another uses long bolts.

EDIT: That's not why the cutout is necessary, now I think about it, but it is why the Shimano tool is a C rather than an O, like a lockring tool.

CramCycle

tomasrojo wrote: »

That's very decent of you. I'll have a think about this very kind offer!

You do need a gap in the circle of whatever is interfacing with the crenellations, because the connectors for the wires and spade coming down from the front light would get in the way of a complete circle, which is why the Shimano tool is like a C in profile, and why one homemade tool has this cutout:


... and another uses long bolts.

EDIT: That's not why the cutout is necessary, now I think about it, but it is why the Shimano tool is a C rather than an O, like a lockring tool.

In case you wonder why my PM says pretty much what you said, it is because I had't seen this message.

adrian522

I'm so annoyed at my own stupidity.

I was putting some clipless pedals on my bike and to practice I wanted to put it on the turbo trainer.

It's a new bike so was first time taking off the wheel. Thru axel and disc brakes are both pretty new to me.

Anyway I had a lot of difficulty putting the wheel back on, seemed a lot more tricky that the quick release/rim brakes on the old bike. Anyway it seems I've somehow managed to break a gear cable as I now can't shift up on the rear derailleur. Added to that no where can take it for repairs for a few weeks so now I'm back on the old bike

cletus

adrian522 wrote: »

I'm so annoyed at my own stupidity.

I was putting some clipless pedals on my bike and to practice I wanted to put it on the turbo trainer.

It's a new bike so was first time taking off the wheel. Thru axel and disc brakes are both pretty new to me.

Anyway I had a lot of difficulty putting the wheel back on, seemed a lot more tricky that the quick release/rim brakes on the old bike. Anyway it seems I've somehow managed to break a gear cable as I now can't shift up on the rear derailleur. Added to that no where can take it for repairs for a few weeks so now I'm back on the old bike

If it's a broken gear cable, you'd see that at the derailleur. You say you can't shift up, can you shift down?

adrian522

cletus wrote: »

If it's a broken gear cable, you'd see that at the derailleur. You say you can't shift up, can you shift down?

Not sure really, the chain goes to the bottom ring when I pedal and I can't shift off it. If I manually move the chain to a middle ring it still goes back to the bottom ring when I pedal.

cletus

adrian522 wrote: »

Not sure really, the chain goes to the bottom ring when I pedal and I can't shift off it. If I manually move the chain to a middle ring it still goes back to the bottom ring when I pedal.

That sounds like a broken cable, but like I said, you'll see this at the derailleur. Take a picture and post it up.

Replacing a cable is relatively simple

adrian522

What would you need a photo of? The cable routing is internal, do you mean a photo of the derailleur?

cletus

adrian522 wrote: »

What would you need a photo of? The cable routing is internal, do you mean a photo of the derailleur?

Yeah, take a pic of the derailleur. It'll be clear if the cable snapped

adrian522

cletus wrote: »

Yeah, take a pic of the derailleur. It'll be clear if the cable snapped

See attached.

cletus

If you look at where the cable is clamped into the derailler (it will be past the adjuster on at the derailler end of the housing, can't see it in the picture), you should be able to tell if the cable is snapped by pulling on it. If its broken, there'll be plenty of slack, it will pull through the housing. Also, pressing the shifter lever should take much less pressure, it should click freely if there's a break, and the derailleur itself should'nt move at all

cletus

I just had a look at the video there, tomasrojo. The tool he made would be very easy to make. You would even have to file the bolts square. As long as the diameter was a fairly snug fit you'd be fine. A flat metal bar, two bolts, a hacksaw and a drill should see you right.

If you don't have the material to make the tool, a pin spanner might work in a pinch, but I don't see why the screwdriver and hammer method cramcycle mentioned wouldn't work. The lock ring on the hub is unlikely to be much more tight than the lock ring on a BB. And even if it's a bit tighter, the shock from the impact should help loosen it

tomasrojo

cletus wrote: »

I just had a look at the video there, tomasrojo. The tool he made would be very easy to make. You would even have to file the bolts square. As long as the diameter was a fairly snug fit you'd be fine. A flat metal bar, two bolts, a hacksaw and a drill should see you right.

Yeah, I was thinking I could borrow a drill. I only have a hand drill, as most handiwork I have to do is with wood, and I try to minimise my use of powertools, as my attention tends to wander.

The one thing thta gives me pause is there's another video where the guy said his first attempt with thinner metal ended up with the metal failing, so he went with a piece of channel iron instead, and drilled a third bigger hole for the axle exit point to pass through. His internal assembly seemed to be screwed in a lot tighter than was the case in the first video.

cletus wrote: »

If you don't have the material to make the tool, a pin spanner might work in a pinch, but I don't see why the screwdriver and hammer method cramcycle mentioned wouldn't work. The lock ring on the hub is unlikely to be much more tight than the lock ring on a BB. And even if it's a bit tighter, the shock from the impact should help loosen it

I shouldn't have said lockring; the crenellations are an integral part of the dynamo body, so the you have to move a lot more mass than hitting a lockring with a chisel/screwdriver. But I think you and Cram are probably right that it would work.

I've ordered the internal assembly anyay, and holding off on the tool for the minute, while I deliberate!

cletus

Make the tool from whatever materials you can get your hands on. It's not going to be an heirloom piece

When you say you've only got a hand drill, do you mean like a carpenter's brace, or egg whisker style, where you have to manually turn the chuck?

If so, yes, minimum you'll need is a battery powered drill. Make sure whoever is loaning it gives you the appropriate drill bit too. You'll want a HSS bit

Also, just to correct my previous post, I intended to say that you wouldn't need to file the bolts square

tomasrojo

cletus wrote: »

Make the tool from whatever materials you can get your hands on. It's not going to be an heirloom piece

Yeah, a tool you need every 30,000 or 40,000km isn't one you'd have at the front of the shelf is it?

cletus wrote: »

When you say you've only got a hand drill, do you mean like a carpenter's brace, or egg whisker style, where you have to manually turn the chuck?

Yeah, sorry, hand-powered, I meant: egg-whisk style. I just borrow a power drill for jobs with metal and concrete. All the men in my immediate family have them; they all have better powers of concentration than I do!

Richard Hillman

I have 622x19 Rims on my hybrid bike with 700x38 tyres. I'm looking to replace the tyres. If my rims are 622x19, can I basically put any tyre on that is 700 x low 20s to high 30s? It has disc brakes so I'm OK for clearance generally.

Type 17

Yes, you have a wide (no pun intended) range of choices, but there are limitations - if you fit a tyre that is too wide for the rim, the bike may handle poorly as the tyre tends to roll around from side to side on corners, and the tyre may suffer from wear where the rim meets it (just beside the bead). Tyres that are narrower than the rim can leave the rim open to accidental damage if the wheel is rubbed off a kerb.

Here's a guide: https://www.lightbicycle.com/newsletter/tire-size-chart-for-bicycle-rim.html

Richard Hillman

Type 17 wrote: »

Yes, you have a wide (no pun intended) range of choices, but there are limitations - if you fit a tyre that is too wide for the rim, the bike may handle poorly as the tyre tends to roll around from side to side on corners, and the tyre may suffer from wear where the rim meets it (just beside the bead). Tyres that are narrower than the rim can leave the rim open to accidental damage if the wheel is rubbed off a kerb.

Here's a guide: https://www.lightbicycle.com/newsletter/tire-size-chart-for-bicycle-rim.html

Excellent thank you. My tyres are quite wide for the rims and I do notice a specific corner that I regularly take where it feels like the rear is slipping. And then wear i have noticed is actually at the sides.

That makes a lot of sense now, thank you

tomasrojo

I ordered that Shimano dynamo hub tool, by the way. I got paid for some teaching on Sunday, and I thought I might as well make things really straightforward, and I'd thought I might have a stronger chance of having the current internal assembly as a slightly wonky but otherwise undamaged back-up in the event that it's screwed in insanely tight, for while I'm so dependent on the cargo bike.

Thanks for all the advice and Cram's offer of dremel and socket help.

Don't judge me harshly!

padyjoe

I'm looking for wheelsets at the moment. How can I make sure that the Shimano hub is 9 speed compatible on the rear? The infos sometimes are contradicting themselved.

adrian522

cletus wrote: »

If you look at where the cable is clamped into the derailler (it will be past the adjuster on at the derailler end of the housing, can't see it in the picture), you should be able to tell if the cable is snapped by pulling on it. If its broken, there'll be plenty of slack, it will pull through the housing. Also, pressing the shifter lever should take much less pressure, it should click freely if there's a break, and the derailleur itself should'nt move at all

Thanks for your help, it didn't need a replacement cable, just an issue with the tension on the cable. Took the place I bought the bike in around 3 mins to fix. Doesn't say much for the guy in local bike shop.

Pdoghue

Hello,

I need advice about a fork.

I have a BH QUARTZ DISC ULTEGRA 2017 road bike. I bought it in Spain in 2018. There is a problem with the fork and so I need a replacement. Not covered under warranty - I checked.

Upshot is, it's proving difficult to source a replacement fork from BH.
Question: do I have to get a specific BH fork, or could I get another make/model? I've been told I need a 9 mm disc brake fork.

Type 17

You don't have to get a BH fork, but you will need one that has the correct dimensions. Given the amount of stuff to get right (see below), I'd give your fork to a shop and let them work out which one(s) they can get which will fit.

You'll want a carbon fibre one, to match your frame and keep the quality-level similar to the rest of the bike
Wheel diameter 700c - needs to match, but almost every road bike uses this wheel size
Dropouts - pics online seem to show a thru-axle on the front - could be 12mm diameter skewer (Road) or perhaps 15mm (more likely MTB), but check to be sure - needs to match.
Disc brakes - a 2017 bike with Ultegra almost certainly uses 160mm disc on the front but measure yours to confirm.
The brake calliper mounting type is called direct-mount - needs to match.
The steerer-tube (the tube that goes inside the frame) diameter is probably 1⅛", but check your existing one. It might also be tapered (wider at the bottom) - needs to match.
There may also be different chamfer-angles where the lower headset bearing sits (crown seat), so this needs to be checked too.
Steerer tube length - this varies by frame size, but a spare-part fork will have a long one to cover all sizes, but will need to be cut (cut properly square, using a mitre). Cutting carbon needs a special hacksaw blade to prevent splintering, and the dust is really bad for your lungs, so probably get a shop to do it for you. Some carbon forks have aluminium steerers, which are easier to cut, but then you also need to set the star-clip for the top-cap bolt after cutting - shops have a tool for this.