Mechanics and Fixing Any Questions Answered

I’ve taken a representative sample of them, well worked on quite a few and they have all been the same. I’ve tried to push the bearing on to the axle out of the frame and the NDS goes on ok, but the DS is ever so slightly bigger. I thought it was a well know as none of my colleagues were surprised.

Coolio! Those NBD cranks sat on the shelf may live again then :D

Well, I've now got my gravel cranks fitted to the Mason using the Shimano bottom bracket. That bit seems ok. The chain angle looks more extreme than before but maybe I've never taken notice of it when cross-chaining.

It's quite slack in the small-small end, so you reckon I could lose a link from it?

This is what it looks like in big-big. I reckon I could run this one link shorter since I should never actually be in this gear but then again I don't want to remove a link and make it too short. But I'm sure my TT bike had the RD at a much more extreme angle than this.

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Can you pull the chain together in big/big to simulate dropping a link?

Good idea. I basically just pushed the cage up and eyeballed a fair amount of movement. Your way is a bit more accurate.

Yeah, I reckon I could lose another link.

I guess the poor Ultegra ain't up to dealing with 46/30 x 11-42

Mason seatpost clamp just let go. (hot tip: don't work on bikes before coffee and remember the wrong bike's clamping force - Mason is 4Nm)

Before I get another of the same, didn't you used to have a thing for a particular brand/design of clamp @gbj_tester ?

https://masoncycles.cc/products/mason-macro-seat-clamp-31-8mm

Actually my seatpost clamp doesn't have those two bits of cylindrical steel - it must be an older version.

The one pictured is of the #tester_approved design, I usually suggest the BBB version as it's widely available which is so similar that I wouldn't be surprised if Mason had gone to BBB's OEM department 🙂

Try and get same again, that style with both parts of the bolts in floating eyelets are the best ive come across

If its just bolt thats snapped get another, pretty impressive if you've broken any other part of it?

Awesome. I'll buy the Mason one because matchy matchy. They must've updated it at some point as mine is the more basic clamp, ie. one piece of metal and a bolt.

Mine is different, an older version, it doesn't have the little steel barrels.

I'm surprised I didn't break it out on the road when fucking around after crashes and stuff to be honest. I stupidly gave it 5Nm instead of 4Nm with a new post installed and I felt an odd pop. It had cracked across the front.

1. Seat post clamp - 4Nm
   
2. Stem to handlebar - 5Nm
   
3. Stem to fork steerer - 5Nm
   
4. Fork steerer top cap - no torque setting for this, secure it until there is no play but the headset turns freely
   
5. Carbon fork mudguard near axle - 3Nm
   
6. Carbon fork mudguard near steerer - 3Nm
   
7. Carbon fork brake mount - 5Nm
   
8. Frame brake mount - 5Nm
   
9. Frame bidons - all frame eyelets are 3-4Nm
   
10. Frame front derailleur clamp - 3Nm
    
11. Seat to seat post - 7Nm
    
12. Rear thru axle - 9Nm
    

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No idea what the industrial standard is, but I’m surprised 1Nm above stated torque limit caused a seat post clamp to fail. It’s one of the parts that gets hamfisted the most on a bike.

What's the old forum joke about @hippy again?

It's has had a lot of use. I've traveled with this bike quite a lot and things like crashing with saddle bags on probably cause some pretty wonky forces. I didn't actually check but it's entirely possible my failing eyesight and lack of coffee actually put the line over 5Nm.

I found a spare clamp I can use until the replacement turns up. Another option might be that I've not seated it properly when swapping the post and it got tightened on an angle - doesn't look that way though.

Oh, during Brimstone I was bashing the bike onto a wooden post in an attempt to get the Di2 battery out. That's probably not in most seat clamps normal life cycle! :D

#hippyisfat

Lucky I wasn't on the bastard when it broke.

This doesn't look like it has been installed properly. The diameter of the tube in the bottom part of the clamp looks larger that the diameter in the top part. Which would explain why it has snapped.
The ISO standard for critical bolt failure on seatpost /handlebar /stem is minimum 20% above manufacturers stated max.

That's after it snapped though. I was holding the post while tightening and could feel it move up.

It's possible but unlikely that it wasn't flush with the seat tube. I don't think I've ever removed the clamp so fail to see how it could've not been flush in x years, especially given the bashing last weekend.

I'm putting it down to old age, lots of 'during race' use where it wouldn't always have been torqued with a torque wrench, etc.

I've got a spare clamp on for now, until the Mason replacement arrives.

Fork steerer top cap - no torque setting for this, secure it until there is no play but the headset turns freely

You can use 5Nm after tightening the steerer clamp of the stem. The torque used to set the bearing preload isn't enough to stop the preload screw rattling loose, but the bolt tension due to 5Nm isn't enough to move a tightened stem and affect the bearing preload

Carbon rim brake question. I'm using some Mavic Cosmic Pro Carbon SL USTs as my summer wheels, thing is the yellow Swisstop Mavic pads that you're supposed to use with them are dogshit. They've basically disintegrated after 400k of Essex riding (I'm not hooning it down mountainsides).

I've got a set of Black Princes spare that I'm considering using instead, but wondered whether anyone else has experience of using non-proprietary pads on carbon rims. Mavic says it'll wear the rim out faster and void the warranty. I'm not really concerned about the warranty, I bought them second-hand off a forumer so don't have one and I tend to lean more towards pads that'll stop me.

Just want a second opinion on whether it's safe, really...

I do that sometimes. I never torque it though, just add a lil' summin' summin' to it.

Headset Garnish™

I've heard good things about the Lifeline pads
https://www.wiggle.com/p/lifeline-performance-carbon-road-brake-inserts-pack-of-4

@dubtap you still use them?

Yeah they are dirt cheap, will stop you (I'm like 100kg and some change) and wear out quickly which I'd rather have than replace rims. These Light Bicycle clinchers are now into their 8th summer of cycling and still not dangerous.

Lifeline brakes pads are allegedly all Ashima and basic Ashima carbon pads all have the same oblique segments as Lifeline so seems to stack up.

Another Lifeline carbon pad user here, they're super cheap and work really well (for carbon pads) I'm sure there's pads out there that work better to a degree, but they're usually 8 times the price for not 8 times the stopping power

I thought (naïvely) having about a million different bottom bracket tools I would be cover for fitting one of these SM-BBR60 bottom brackets. I was expecting that some combination of the below would have worked. Does anybody know what I need, there is conflicting information on wiggle, surprise surprise.

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I find wolftooth to have the easiest BB tool chart: https://www.wolftoothcomponents.com/collections/tools/products/bottom-bracket-tool
You need a 41mm, 16 notch tool. The shimano adapter should be the TL-FC25.