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

The issue in the SRAM doc is to do with adjusting the B-angle, whereas your issue is to do with axle-spacing. Best chat to your LBS. Did the rear wheel come with the bike, or is it a replacement?

Long story short: it turns out I have frikishly short legs and despite 195cm of height I need shorter cranks. I'll be going from 175 to 170mm, so I have to change the chainset. While doing so I'd like to go from the Cx 46/36 I am riding now to 46/30 - while climbing my hills around I am hitting cadences of 60 and still get over 95% of MaxHR. Smaller small cog should help with that.

So, I can see three options:
* FSA Omega Adventure 46/30 - rather rare and I'd like to avoid as they use the exotic 19mm spindle with bottom brackets costing far too much long term
* Shimano GRX FC-RX600-10
* Shimano MT210 (Alivio level) - it is much cheaper and have the added benefit of much wider Q-Factor (suprisingly tall people have wide pelves too and often cycle with pedal spacers). Weight penalty over GRX isn't that big - around 100g.

Is swapping the Ultegra road chainset for a MTB one even doable? Am I right to assume I'd need to get MTB BB and use spacers on my 68mm frame? Is the chain line difference of 5.5mm (43.5 vs 48.8) going to be an issue (might be for the front derailleur I guess)? Getting GRX would be much simpler, but cause it is trendy, it is costly for what you're getting.

I am open to ideas here. Maybe there are better MTB chainsets I could consider?

Recommendations for best Shimano compatible brake shoes and pads?

Rezident wrote: »

Finally found my new road bike - Giant Defy Advanced 3, ticks all my boxes, but it is tubeless.

Now I have googled tubeless a bit but have not used it before. I have been cycling years but am poor at maintenance (I just drop it in to LBS) I don't even do my own punctures anymore (getting old and lazy and the Polish guy in the shop does a way better job than me anyway).

Is tubeless that hard to get used to? What happens when you do, inevitably on Irish roads, get a flat, do you have to carry sealant around with you as well as a pump? Sounds great in theory but do you need much extra equipment etc.?

Most bikes come tubeless ready, and aren't shipped tubeless. So, unless Giant are different to other major manufacturers, your bike will come with tubes fitted and the possibility to convert to tubeless if you want to.

The people who like tubeless, love tubeless.
The benefits:
- Fewer small-hole punctures (plugged by sealant)
- Ability to run at lower pressure means more comfort
- lighter than most tube setup equivalents

The drawbacks
- Requires regular sealant top-ups
- Tricky to mount tyres and initial seating requires a special high volume pump

Lots of road riders will carry a spare tube to put in if they get a cut on the tyre that the sealant can't plug. Also carrying Co2 is a good idea, as you can top up a tyre that has had a puncture but sealed successfully.

Someone with more experience of tubeless might be able to tell you some more. I wouldn't let it put you off buying the bike however.

Type 17 wrote: »

No, the SRAM doc is about the front of the derailleur (where the parallelogram body meets the swing-cage) touching the chainstay when the chain is on the 10 sprocket. Usually the B-angle (AKA chain-gap) is adjusted to suit when the chain is on the biggest sprocket, but when the biggest sprocket isn't that big, this may may mean that the derailleur touches the chainstay when the chain is on the smallest sprocket, so the doc is saying to use a compromise setting to keep the top jockey wheel as close as possible to the cassette, while not touching the chainstay when on the smallest sprocket.

None of this has anything to do with your issue, which is not caused by the size of cassette fitted.

Thanks for the detailed explanation. Very clear now. I picked it up wrong and guess it's a non issue. Went out for a spin today and sure the stay got a little oil but chain does not appear to be rubbing. My other wheels did the same from new. I'd say there is a mm of a gap at most.

Hi.

I have a "squeak" in around the left side of the bottom bracket & would appreciate some expertise eliminating it.
The squeak happens when im putting in a little more than idling effort, pressing down on the left crank, so its difficult to reproduce on the stand.

What I have tried:
Im 100% sure the noise is coming from down where the left crank joins the bike but based on various blogs & discussions ive checked and eliminated the following:
- Saddle.
- Saddle post & nut.
- Lose chain rings.
- Chain (it couldnt be more lubricated).
- Pedal.
- shoes.

I took off the left crank and added some grease, which removed the squeak for a couple of spins but its back again.
Before i take the crank off again and pack it with grease, id like to get some advice on what it could be.

WRT the bike, its less than 6 months old, does not have huge mileage and is taken care of.
Its a Cube Road Race with a Shimano 105 FC-R7000, 50x34T


Appreciate any advice on what to check.

Technically, it's possible to over grease bearings etc., but realistically it's only an issue in high speed applications, where the excess grease gets "churned", causes excessive heat and can cook the bearing or destroy the seal. It's unlikely to be an issue in a bottom bracket

8valve wrote: »

Grease the 'face' of the bottom bracket bearing where the crank makes contact with it?


Remove the bottom bracket bearings, grease threads and refit/retorque?


IMO, There is no such thing as too much grease...lash it on and remove any that squidges out once the bike has been in motion; any that remains will both lubricate and act as an effective water resistant seal.

Thanks for the replies all!

WRT "retorque", is it critical to have this near bang on? I dont have a large torque wrench, just one with an upper limit of 15Nm, so would have to guess.
In this case, would it be better to just bring it to bike mechanic?

Type 17 wrote: »

It is important to get the torque (fairly) right on a Shimano Hollowtech II crankset or similar designs - the two 5mm Allen bolts should be 12-14Nm, and the important bit is that they're not too tight (thread damage), but also not too loose - if too loose, they will fall loose in riding, and the LH crank splines will skip and shear off, leading to a fall and the LH crank being ruined.

It's also very important that the two bolts are torqued similarly tight, because if they're not, the looser bolt will fall fully loose and the remaining one's threads will then fail under heavy load, also leading to the shearing mentioned above.

When tightening paired bolts like this (also seen on stems & some Giant seatpost clamps), note that tightening one bolt makes the other fall loose a bit, so you have to "walk them up" to the correct torque in a few steps (tighten one then the other x 3 or 4), until they are both the required torque.

What he said! :rolleyes:


Carbon bikes are the only ones I use a torque wrench on; everything else is done by feel, based on experience.


Bikes are not subjected to massive forces, so there's no need to go all HUUUULK SMAAAASH, when tightening stuff up. A particular pet hate of mine.

Deano12345 wrote: »

So I may be going down the dark path of having a Campag bike in the stable. Won an eBay auction for an almost old enough to be cool Willier Laverado Crono. Seems to be running 10 speed Campag.

I know compatibility ain’t great between them and other brands. It’s a weird setup in that the “base” bar is just a set of bullhorns with the brifters on the end!

If I wanted to convert it properly to TT bike spec, would any set of bar end levers, like the Dura Ace ones that pull the cable (not r2c) work? Google tells me it should!

If it’s going to be a faff, I’ll just put drop bars on it and have a fast aero bike I guess!

JTEK do a range of SHIFTMATE shift cable pull converters, that will allow you to run any combination of Campag/Shimano shifter/derailleur/cassette.


Their website has a table that allows you to work out which one you need, based on the components you are using.

Deano12345 wrote: »

Thank you kindly!

Sounds like that’ll do the trick, I’ll post pictures of the process of cleaning it all up once it arrives too!

you are most welcome!


I have used one for a shimano ten speed cassette with campag chorus 10 speed shifters/rear mech on my old Merckx and shifting is perfect.


looking forward to pics.


P.

grogi wrote: »

Long story short: it turns out I have frikishly short legs and despite 195cm of height I need shorter cranks. I'll be going from 175 to 170mm, so I have to change the chainset. While doing so I'd like to go from the Cx 46/36 I am riding now to 46/30 - while climbing my hills around I am hitting cadences of 60 and still get over 95% of MaxHR. Smaller small cog should help with that.

So, I can see three options:
* FSA Omega Adventure 46/30 - rather rare and I'd like to avoid as they use the exotic 19mm spindle with bottom brackets costing far too much long term
* Shimano GRX FC-RX600-10
* Shimano MT210 (Alivio level) - it is much cheaper and have the added benefit of much wider Q-Factor (suprisingly tall people have wide pelves too and often cycle with pedal spacers). Weight penalty over GRX isn't that big - around 100g.

Is swapping the Ultegra road chainset for a MTB one even doable? Am I right to assume I'd need to get MTB BB and use spacers on my 68mm frame? Is the chain line difference of 5.5mm (43.5 vs 48.8) going to be an issue (might be for the front derailleur I guess)? Getting GRX would be much simpler, but cause it is trendy, it is costly for what you're getting.

I am open to ideas here. Maybe there are better MTB chainsets I could consider?

Just to answer myself here...

With the introduction of GRX Shimano increased the chainline with the GRX from 43.5 to 46.9mm to accomodate wider tyres. Typical road FD has only capacity to deal with chainline upto ~45mm (there isn't much more reach on mine from what it is doing now) and with the GRX might not reach far enough and GRX FD will be required. The chainline will be even bigger issue when trying to use MTB chainset.

It seems the easiest and definately most cost effective option is to go with the FSA Omega Adventure.

Whats the best way to deal with bangs and scrapes on the body of a bike? Tape them over? Or is there a sealing spray or something you can get?

fixXxer wrote: »

Whats the best way to deal with bangs and scrapes on the body of a bike? Tape them over? Or is there a sealing spray or something you can get?

Nail varnish does an ok job of covering them up. If you can't match the colour, clear nail varnish isn't too bad. I don't know how good a job it does of preventing oxidation on the underlying metal though.