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

Paul Kiernan · 22-04-2021 01:28PM

Pdoghue wrote: »

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.

A compatible fork will need to have the same bearings, flat mount discs and wheel mount (i.e thru-axle or Quick Release). If you loosen up the stem and remove the fork you can get the bearing numbers for the top and bottom of the head tube. I'm surprised BH can't help as it's probably a still current fork! If it's QR and current are thru-axle you could switch to thru-axle and get new wheels! Many wheels can be set up as QR or thru-axle.

Pdoghue · 22-04-2021 01:41PM

Type 17 wrote: »

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.

Thank you very much for the help.

Pdoghue · 22-04-2021 01:43PM

Paul Kiernan wrote: »

A compatible fork will need to have the same bearings, flat mount discs and wheel mount (i.e thru-axle or Quick Release). If you loosen up the stem and remove the fork you can get the bearing numbers for the top and bottom of the head tube. I'm surprised BH can't help as it's probably a still current fork! If it's QR and current are thru-axle you could switch to thru-axle and get new wheels! Many wheels can be set up as QR or thru-axle.

Thanks very much - it's a real struggle trying to source a replacement from BH. I will have to go down the compatible fork route soon if I don't get success from BH themselves.

Paul Kiernan · 22-04-2021 02:07PM

Pdoghue wrote: »

Thanks very much - it's a real struggle trying to source a replacement from BH. I will have to go down the compatible fork route soon if I don't get success from BH themselves.

Some of the earlier BH Quartz had QR before they switched to thru-axle. Which is yours? AFAIK they always used 1.125 to 1.5 tapered steerers. This type of carbon fork with thru-axles is the de-facto standard now and on almost every new mid to high level disc brake bike. It should be fairly easy to find, even from BH!

Breezer · 22-04-2021 02:08PM

My rear derailleur is catching and moving forwards when freewheeling. Video here: https://www.dropbox.com/s/jfk1yhm2op8402b/IMG_5613.mov?dl=0. This started after I cleaned the chain and lubed it up again. I definitely used too much lube.

I've searched online and read that a dirty freehub body is the most likely cause, which would make sense. However, I have a separate problem in that I can't get my cassette off! It won't budge and I managed to bend my chainwhip before giving up because I didn't want to damage the cassette (if I haven't already...)

So I've cleaned the drivetrain as best I can without removing the cassette. Put it all back together and the video is the result.

I guess I'm asking if anyone can confirm a dirty freehub body is the likely cause, before I start all over again. And also, any ideas for a stuck cassette?

gaffmaster · 22-04-2021 03:09PM

I had this problem the winter before last on a Mavic Aksium rear wheel. "Wheel Suck" I think is what people call it, and essentially, the free hub internals need a clean and regrease. Had that done and it worked perfectly again after.

Some wheel freehubs can be accessed without removing the cassette - someone with better knowledge can provide more info perhaps?

Type 17 · 22-04-2021 03:24PM

Yes, definitely a dirty freehub.

For the tight cassette, straighten out your chainwhip(!), and use a lever on the cassette lockring tool that is at least as long as the chainwhip.

Have a look at the below pic, and stand with the wheel/tools in this position.

If a good push down on your right arm isn't doing it, you need to jerk it free (rather than just pushing harder), so lift the wheel up about 6 inches/15cm and slam it down on the ground hard (ensure tyre is pumped up!), following through with your body-weight on your right arm only. You may need to do this a few times to get it to budge. Most cassettes have toothed facing surfaces on the lockring & outer sprocket, so it's easy to over-tighten them and to need to open it this way, but they are built to take your entire effort, so you won't snap anything, once a tool doesn't slip.

F0V9G2XHTNO6RXV.jpg?auto=webp&frame=1&width=900&height=1024&fit=bounds&md=0a23efc25759a64f59342fa94dd7577e

F0V9G2XHTNO6RXV.jpg?auto=webp&frame=1&width=900&height=1024&fit=bounds&md=0a23efc25759a64f59342fa94dd7577e

Breezer · 22-04-2021 03:27PM

Thanks guys. I live a 5 minute walk from my LBS so I brought it there, they got the cassette off in 5 seconds and I bought a new chain whip to say thank you! I've cleaned the freehub body and it's working fine now.

I didn't actually take the freehub body off (it's a Shimano Deore hub, which I think is sealed?) Do I need to regrease it?

ironictoaster · 22-04-2021 03:43PM

Does this sound normal? Concerned as it's only back from service from my local bike shop. I can't see anything rubbing!

https://streamable.com/88mqpz

magicbastarder · 22-04-2021 03:49PM

is the guide jockey wheel lining up with the smallest sprocket on the cassette? and does it only occur when the chain is on the smallest sprocket?

Type 17 · 22-04-2021 03:51PM

Breezer wrote: »

Thanks guys. I live a 5 minute walk from my LBS so I brought it there, they got the cassette off in 5 seconds and I bought a new chain whip to say thank you! I've cleaned the freehub body and it's working fine now.

I didn't actually take the freehub body off (it's a Shimano Deore hub, which I think is sealed?) Do I need to regrease it?

If it's a sealed Shimano one, then it's not practical to open and you won't be able to get actual grease into it, but reasonably thick oil (dribble-oil from a bottle, rather than thin aerosol stuff) will be fine.
If it's still on the wheel, then you need to take out the axle and put oil between the bearing cup and the outer body and spin it around - add more and spin it again a few times. Listen out for gritty grinding noises (dirt in bearings). If you have taken the freehub off the wheel (remove axle and use a 10/12mm Allen wrench in the drive side), you can also oil the inner (spoke-side) bearings - lift the rubber seal on that side carefully with a toothpick or similar and dribble oil in.

If things are really gritty, and the freehub still sticks, the industrial method/last resort is to remove it from the wheel, spray in loads of degreaser to wash everything out, blow through the gaps with a compressed air nozzle, (degrease and blow through again, if required), and then rinse with fresh water and blow through to dry it out before oiling (washing with water is required, as degreaser will break down the oil causing future damage from no real lubrication).

Type 17 · 22-04-2021 03:59PM

ironictoaster wrote: »

Does this sound normal? Concerned as it's only back from service from my local bike shop. I can't see anything rubbing!

https://streamable.com/88mqpz

Is it a steady rubbing noise, or is it a random gritty noise (it's hard to hear, even with headphones)?
If you (or the LBS) sprays lube into the freehub/freewheel, it's possible to wash dirt into the bearings and for it to make a gritty noise whilst pedalling - even though the freehub bearings aren't rotating during pedalling, they do squirm about as the load rotates about the freehub's axis, causing any grit present to get crushed noisily.

Edit: listened again, and it does sound like gritty bearings (as mentioned to Breezer above). It'll be worst on the smallest sprocket as the load on the outermost end of the freehub causes more squirming/movement, but will be audible in most gears.

ironictoaster · 22-04-2021 04:14PM

magicbastarder wrote: »

is the guide jockey wheel lining up with the smallest sprocket on the cassette? and does it only occur when the chain is on the smallest sprocket?

Looks in line to me

It seems to get quieter as you go up the gears.

https://streamable.com/nme71j

Breezer · 22-04-2021 05:00PM

Type 17 wrote: »

If it's a sealed Shimano one, then it's not practical to open and you won't be able to get actual grease into it, but reasonably thick oil (dribble-oil from a bottle, rather than thin aerosol stuff) will be fine.
If it's still on the wheel, then you need to take out the axle and put oil between the bearing cup and the outer body and spin it around - add more and spin it again a few times. Listen out for gritty grinding noises (dirt in bearings). If you have taken the freehub off the wheel (remove axle and use a 10/12mm Allen wrench in the drive side), you can also oil the inner (spoke-side) bearings - lift the rubber seal on that side carefully with a toothpick or similar and dribble oil in.

If things are really gritty, and the freehub still sticks, the industrial method/last resort is to remove it from the wheel, spray in loads of degreaser to wash everything out, blow through the gaps with a compressed air nozzle, (degrease and blow through again, if required), and then rinse with fresh water and blow through to dry it out before oiling (washing with water is required, as degreaser will break down the oil causing future damage from no real lubrication).

Thanks. I ended up only having to scrub the outside of the freehub body and it's fine now, just been out on it and all good.

Of course, I managed to overtighten the lock ring when putting the cassette back on, and now can't get it off again. Job for another day. I'm special today

CramCycle · 22-04-2021 05:40PM

ironictoaster wrote: »

Looks in line to me
It seems to get quieter as you go up the gears.
https://streamable.com/nme71j

Cross chaining or an alignment issue.?

ironictoaster · 22-04-2021 08:04PM

CramCycle wrote: »

Cross chaining or an alignment issue.?

I have no idea to be honest. I am usually in the 4th hardest gear in the big chain ring 90% of the time.

I rarely use my hardest or easiest gear in both chain rings so I can't see myself cross chaining.

Mundo7976 · 22-04-2021 08:09PM

Maybe try turning the barrel adjuster slightly, quarter turns at a time?

CramCycle · 22-04-2021 08:40PM

ironictoaster wrote: »

I have no idea to be honest. I am usually in the 4th hardest gear in the big chain ring 90% of the time.

I rarely use my hardest or easiest gear in both chain rings so I can't see myself cross chaining.

Sorry, badly explained, I mean its an alignment issue and its is relieved/exacerbated by cross chaining in your video, if that makes sense. Just an idea but it sounds like my 9 speed when it wasn't aligned.

ironictoaster · 22-04-2021 10:07PM

CramCycle wrote: »

Sorry, badly explained, I mean its an alignment issue and its is relieved/exacerbated by cross chaining in your video, if that makes sense. Just an idea but it sounds like my 9 speed when it wasn't aligned.

Sorry Cram. I'm still new to cycling. First bike since I was a child. What do you think needs to be alligned exactly?

I am completely out of my depth with bike maintenance outside cleaning and lubing the chain!

magicbastarder · 22-04-2021 10:19PM

the reason i asked why it was only in the smallest cog when you heard the noise was that there are limit screws on the derailleur - no matter how the derailleur is adjusted with cable tension, etc., the limit screws prevent the derailleur from moving outside its high and low limits. i.e. to prevent the chain going past the largest or smallest cogs. so you can play with the limit screw which won't adjust the indexing in other gears, but it could prevent it from aligning with the smallest cog, and sounding 'chatty'.

Mundo7976 · 23-04-2021 12:14AM

ironictoaster wrote: »

Sorry Cram. I'm still new to cycling. First bike since I was a child. What do you think needs to be alligned exactly?

I am completely out of my depth with bike maintenance outside cleaning and lubing the chain!

Cal Jones might be able to help you out, thorough video helped me out.
https://youtu.be/UkZxPIZ1ngY

MangleBadger · 23-04-2021 10:57AM

Confirmed rear derailleur cable snapped at the hoods. So off to find a replacement cable. Might as well replace the front as well.

Should I replace the outers as well? If I don't have to I can possible route the cable through without having to rip off my bar tape?

magicbastarder · 23-04-2021 11:02AM

the outers were not a factor in the break i assume? when were they last changed?

MangleBadger · 23-04-2021 11:18AM

magicbastarder wrote: »

the outers were not a factor in the break i assume? when were they last changed?

Never been changed. Bike is 18 months old. Cable snapped where it joins the hood it appears

Pdoghue · 23-04-2021 12:26PM

Paul Kiernan wrote: »

Some of the earlier BH Quartz had QR before they switched to thru-axle. Which is yours? AFAIK they always used 1.125 to 1.5 tapered steerers. This type of carbon fork with thru-axles is the de-facto standard now and on almost every new mid to high level disc brake bike. It should be fairly easy to find, even from BH!

Mine is quick release. The part seems be "Quartz Evo Disc Integrated Tapered Full Carbon 1.5"

BH Bikes themselves don't stock this: https://www.bhbikes.com/en_GB/equipment/cycling-components/forks-mtbs-road-bicycles

Plus they weren't very helpful in trying to help me source the fork. They told me to contact the nearest BH agents. I've emailed about 10 of them so far and none have replied.

Large bottle small glass · 23-04-2021 12:34PM

MangleBadger wrote: »

Never been changed. Bike is 18 months old. Cable snapped where it joins the hood it appears

There is no point having expensive and precisely engineered Italian or Japanese technology at either end of your bike if you don't properly maintain what connects them.

Regularly changing both inners and outers will ensure better shifting (even with lower end shifters and derailleurs) and give a longer lifespan for your shifters.

Buried gear cables are a backwards step in terms of function and ease of maintenance; 7800 FTW

cletus · 23-04-2021 12:38PM

Large bottle small glass wrote: »

There is no point having expensive and precisely engineered Italian or Japanese technology at either end of your bike if you don't properly maintain what connects them.

Regularly changing both inners and outers will ensure better shifting (even with lower end shifters and derailleurs) and give a longer lifespan for your shifters.

Buried gear cables are a backwards step in terms of function and ease of maintenance; 7800 FTW

In fairness, I wouldn't think that a bike would need to have inner and outers changed after only 18 months

07Lapierre · 23-04-2021 01:09PM

cletus wrote: »

In fairness, I wouldn't think that a bike would need to have inner and outers changed after only 18 months

Depends on how much cycling you’ve done in the 18 months?

Large bottle small glass · 23-04-2021 01:20PM

cletus wrote: »

In fairness, I wouldn't think that a bike would need to have inner and outers changed after only 18 months

Depends on a lot of things; distance covered, riding conditions, storage conditions, mudguards, inner/outer interface location etc.

I have a road bike which is only out in dry weather and has lubed Dura ace cables, that's a very different proposition to my gravel bike which is out in all types of weather.

I've had mtb which saw a lot of muck and sh1t which had inner cables changed and lubed every few spins.

I put 15k km trouble free over 18 montgs on a tiagra equipped bike with zero maintenance and all weathers but it had a single run of Dura ace inners & outers from shifters to derailleurs cable tied to the frame! Even I struggled with the aesthetics of that

Type 17 · 23-04-2021 01:21PM

Given that the rear inner cable has failed, there's a fair few km's on the bike (or the cable was a stainless steel one, which can fail sooner).

If the gears were working well until they began acting up recently (because the cable was failing and loose wire strands were getting stuck in the shifter mechanism), then I'd leave the outers that are under the bar tape for now.
If the part of the failed inner cable that is in the bit of housing that leads to the rear derailleur itself is dirty or rusty, then I would change this piece of housing, as it gets a lot of road-spray, and is the other main cause of issues (as well as the inner failing at the shifter end).

PS: It's not necessary to change the front derailleur inner cable (unless there are issues), as the usage patterns are quite different than the rear derailleur (al lot less on the front, for most people).

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

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