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

doozerie

CramCycle wrote: »

I used to be against it but in recent times, I really don't see the issue if you keep an eye on your chain and are OK with a slight increase in wear. I have stuck solidly to the big ring and cross chained all year without issue. The slight increase in friction when crossing is minimal and considering it is only on decent climbs that happens, I can live with it. Using a SRAM chain, 1130 I think, previous anecdotal experience tells me it lasts longer than Shimano but this could be BS. It is definetly wearing quicker than in previous years though. At this point I'd be happy enough with a 1X set up for the road.

For me I don't see an actual need to cross chain so adding the extra wear (however marginal) and the potential extra risk (whether it even exists) that it entails aren't choices I ever have to consider. My choice of cassette ratio obviously plays a part here, as does my preferred cadence, so I don't feel the need to cross chain to avoid a significant jump in resistance when changing gear.

That's all personal preference, but there are sometimes other reasons to avoid cross chaining too. As one example, my wife's audax bike currently has 50-34 up front, a 12-34 cassette, and a medium cage rear mech. When sizing the chain for that I had two choices, make the chain short enough that small/small is just about usable but big/big isn't, or long enough that big/big works but small/small (plus 1 gear down from that) doesn't. A lot of the talk about cross chaining assumes that it's always an option, but with some bike setups it just isn't.

I read recently that by default at least one version of Di2 wouldn't allow cross chaining (that's the setting out of the box, you can change it). It's a novel aspect of electronic drivetrains that they can be programmed to either support you, or thwart you, at the whim of the person programming them. They may encourage you to keep on the good side of your mechanic I guess

LollipopJimmy

Yup the R8050 Ultegra on my bike doesn't allow cross chaining

usheeeen

Does anyone by any chance have a spare bolt for clamping the brake cable onto a cantilever arm? I seem to have lost mine when changing the pads and cable. I think its a 6mm bolt.

Dont think any shop would have a replacement and would like to avoid having to buy completely new arms as the bike is only a beater and worth nothing.

Pictures here of the other bolt on the other brake

Type 17

Any standard M6 bolt will work fine. It needs to be a few mm shorter than the hole, allowing for a washer* (cut the bolt if required), and you'll need an M6-sized washer that is thick enough not to deform.

If you can make it to the Donnybrook, Dublin area easily, PM me, and I can give you something suitable.

usheeeen

Type 17 wrote: »

Any standard M6 bolt will work fine. It needs to be a few mm shorter than the hole, allowing for a washer* (cut the bolt if required), and you'll need an M6-sized washer that is thick enough not to deform.

If you can make it to the Donnybrook, Dublin area easily, PM me, and I can give you something suitable.

Yeah I found a m6 bolt but I have no way of cutting it and cannot for the life of me find a washer in my shed. Might take you up on that if I cant find the bolt tomorrow.

Mickiemcfist

This is probably a terrifyingly dim question, I've just started commuting 10k each way into town & I've got an old 21 speed mountain bike which is quite heavy but I do like it as it's comfortable & sturdy & doesn't break my back going over the potholes, kerbs & grates in Dublin. Howweever....the gearing is quite low in that when I build up speed I'm pedalling like a maniac, is there a cost effective way of putting road bike gears on it?

Mc Love

Mickiemcfist wrote: »

This is probably a terrifyingly dim question, I've just started commuting 10k each way into town & I've got an old 21 speed mountain bike which is quite heavy but I do like it as it's comfortable & sturdy & doesn't break my back going over the potholes, kerbs & grates in Dublin. Howweever....the gearing is quite low in that when I build up speed I'm pedalling like a maniac, is there a cost effective way of putting road bike gears on it?

Sounds like the bike I have

magicbastarder

can you check to see how many teeth are on the large chainring, on the front? 44 or thereabouts would be relatively common for a mountain bike.

Mickiemcfist

magicbastarder wrote: »

can you check to see how many teeth are on the large chainring, on the front? 44 or thereabouts would be relatively common for a mountain bike.

Cheers for the reply, I'll have to check when I get home as I didn't cycle in due to the weather.

Type 17

Switch chainsets to a hybrid one (48 tooth big ring). You could look at a road chainset, but then you’ll probably be looking at a different front derailleur and other chain-line and compatibility issues.

Mickiemcfist

Type 17 wrote: »

Switch chainsets to a hybrid one (48 tooth big ring). You could look at a road chainset, but then you’ll probably be looking at a different front derailleur and other chain-line and compatibility issues.

Yea I did the count, there's 44 teeth, if I change to 48 would that mean a 9% increase to top end speed? Thanks again

cletus

usheeeen wrote: »

Yeah I found a m6 bolt but I have no way of cutting it and cannot for the life of me find a washer in my shed. Might take you up on that if I cant find the bolt tomorrow.

You should be able to get a suitable washr in any hardware store. As regards cutting the bolt, a hacksaw will suffice. If you dont have one, maybe check with a friendly neighbour, somebody in work who likes diy etc.

Worst case scenario, Mr. Price sell junior hacksaws for €1.49, which should get you through one bolt

cdaly_

Mickiemcfist wrote: »

Yea I did the count, there's 44 teeth, if I change to 48 would that mean a 9% increase to top end speed? Thanks again

You can buy just the 48t chainring rather than a full crankset. You need to know the number of arms on your crank and the BCD (bolt circle diameter). You'll also probably need to raise your derailleur on the seat tube to accommodate the bigger ring.

That said, you could also learn to pedal faster. 'Spinning' is usually a better way to pedal. You do less work in each pedal stroke but you do more of them. It tends to be less wearing on the knees and more aerobic.

devonp

V brakes adjusting cable tension ..??


so put some new pads on a bike with V-brakes but the pads are rubbing off the rim now...tried adjusting the cable at the anchor bolt..no good
should i adjust the barrel screw at the lever too


is there a sequence to getting the whole system adjusted ??


cheers

Type 17

Screw in barrel adjuster on the brake lever fully.
Unhook springs from behind lugs on arms.
Screw in adjuster screws at bottom of springs all of the way (or most of the way and equally).
Adjust cable in pinch bolt so that there is about 10mm (a fingertip's width) of slack when you jiggle the top of the arms.
Re-hook the springs behind their lugs.
Check the brakes for centring on the rim (ensure wheel isn't excessively buckled).
Open the spring-tensioning screw of the arm that moves too much - work in quarter turns or less.
if you go too far, open the other spring in quarter turns to match.

CantGetNoSleep

This is maybe the definition of a stupid question. I got a new Cannondale Synapse carbon today. I had to take the seatpost out as I was putting it in my tiny car. Somehow the seatpost screw got stuck in the seat tube. I've tried turning upside down, rattling and an old coat hanger (worried about scratching the inside of the carbon) but it seems wedged in there. Any idea on how to get it out?

magicbastarder

Magnet? I'm trying to visualise how that might have happened but I'm not familiar with how the bolt works.

CantGetNoSleep

magicbastarder wrote: »

Magnet? I'm trying to visualise how that might have happened but I'm not familiar with how the bolt works.

I'm not entirely familiar with the mechanism either as it is a new bike - but the seat post clamp seems to be internal rather than the normal one that is bigger than the tube. When looking at the bike normally you can see the seat post and seat tube but not real bolt or mechanism like you usually can.

Some form of strong magnet might be the only option. I can't even get the seat post in where it is wedged so ignoring it isn't an option either

They have manuals on their site for most of the bikes , so you might find a clue there maybe

https://www.cannondale.com/en/USA/Support/OwnerManuals/Road

Is it like in the 2018 model shown there ? Page 9

CantGetNoSleep

Deleted User wrote: »

They have manuals on their site for most of the bikes , so you might find a clue there maybe

https://www.cannondale.com/en/USA/Support/OwnerManuals/Road

Is it like in the 2018 model shown there ? Page 9

Thanks - yeah it is exactly that - the whole piece in figure 1 - so a bolt and some sort of mechanism holding it in place. Whatever way it has lodged itself it just isn't moving. I'll either have to figure out a way to get a piece of string around it and the two ends back out, or else disassemble the bottom bracket and hope that i can push it from there with a coat hanger

Oh nuts so it's more like a lego brick than a simple screw and fig.A there is what should have happened but it's dropped down in the seat tube? How much movement is there in it ? like will it travel up and down the tube?

CantGetNoSleep

[Deleted User] wrote: »

Oh nuts so it's more like a lego brick than a simple screw and fig.A there is what should have happened but it's dropped down in the seat tube? How much movement is there in it ? like will it travel up and down the tube?

Seems to be wedged in - the seat tube isn't a complete circular cylinder all the way down, it changes shape around the upper bottle cage bolt and it just seems to have lodged itself there and not rattling at all

CramCycle

Best I can think of is either upside down and shake the frame like bejaysus, or a coat hanger suitably bent if there is any space to the side of it, can you see it down the tube?

CantGetNoSleep

CramCycle wrote: »

Best I can think of is either upside down and shake the frame like bejaysus, or a coat hanger suitably bent if there is any space to the side of it, can you see it down the tube?

Yeah I have a repair stand - whatever way it had lodged itself it won't come out just by hanging the frame upside down.

I managed to get a bit of dental floss looped around it today by adding a washer to one end but the floss snapped - tried the same with a shoelace but can't get one end of it looped around.

I worry about a coat hanger damaging the carbon if it were to scratch the inside? There is a very small space either side, I got a flag pole that was close to 10mm wide id say up the side of it but it won't move at all. My only options I think are that or disassemble the cranks and bb - but it's a Cannondale so not that easy to disassemble.

Proper weekend ruining stuff it's that frustrating - trying everything and not something I've ever heard of going wrong with a new bike

Would it be simpler to leave it there and try and source a new one from Cannondale or would it cause issue with fitting the seatpost or block it or some other issue?

CrowdedHouse

CantGetNoSleep wrote: »

I worry about a coat hanger damaging the carbon if it were to scratch the inside?

Wrap a layer of electrical tape around the coat hanger ?

CantGetNoSleep

Deleted User wrote: »

Would it be simpler to leave it there and try and source a new one from Cannondale or would it cause issue with fitting the seatpost or block it or some other issue?

With the way it was wedged I'd worry it would damage the seat tube - it would also limit the amount you could lower the saddle as it was less than half way down the tube.

Finally - IT IS OUT though. After trying every tool, kitchen utensil, shoe lace, pieces of string, magnets, dental floss - it somehow wiggled out with a coat hanger with a very small hooked shaped into the end of it, less than the diameter of a pencil. I even made the gf order sushi last night, she thought it was to make up for being in a bad mood all afternoon as she knows I hate sushi even though she loves it - in reality I just wanted the chopsticks.

Hope there is no lasting damage to the inside of the brand new carbon frame - I really had to force it out in the end as it wasn't moving up or down and a few of the things I tried could have scratched by moving the part itself around. There is a gear cable end cover stuck inside the frame somewhere too but I will just have to live with that I think.

Word of warning for anyone getting a Cannnondale frame - don't take out the seatpost without making sure the clamp is secure (even though it was a Cannondale dealer who did this, not me).

Thanks for the advice - one of the more frustrating things I've had go wrong with a bike (and definitely a brand new bike)

Weepsie

I'm assuming this is a no but:

I've a bike that's currently set up with a Compact 50/34 crankset and an 11-32 cassette. The RD is basically at it's limit as it's a Tiagra 4601 (long cage) and it's listed as 30t maximum.

However, if I wished to change the front to a 48/32 or 46/30, will that offset anything and allow me to change to an 11-34 at the back? I basically want to be able to get up a vertical wall!

cdaly_

Yep, that'll work (probably). You're reducing the tooth count of your chainrings by 2 or 4 and increasing the cassette by 2 so the derailleur now has less to take up.

If you're going to 46/30, why not go 46/26 for an even lower climbing gear?

Mind you, I haven't yet managed to climb the Dying Cow in 26x32 (front x rear) without putting a foot down...

Weepsie

I'm stubborn and can get up most things withouts stopping with 26 as my bigest cog, since changed to a 28 and found it easier as you would, but my winter bike, allows for even more experimenting.

Thanks.