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Your questions answered
How to shorten SRAM/ Avid brake hoses, tyre compounds demystified, plus tech Q&A – glazed brake pads, clutch mech problems and Cannondale’s AI back end
GLAZING NOT BLAZING
I’ve been having issues with my brake pads inexplicably glazing after just a month or so. They’re bona fide Shimano resin pads, fitted to Deore XT brakes, and it’s usually the front ones that are affected. I’m careful not to get lube or anything like that near them. Is there any way to resurrect them? There’s loads of pad material left. I’ve heard you can sand them or even bake them in the oven!
Steven Wright, Cheshire
Brake pads glazing over (their braking surface becoming smooth and shiny) is generally due to excessive heat build-up. This then leads to poorer performance and squealing. As a short-term fix, we’ve had good results from sanding back glazed pads, and giving both pad and rotor a good clean. Baking in an oven is something that’s often talked about for contaminated pads, but is unlikely to help with glazing. If yours are contaminated, we’d suggest replacing them.
You could think about upping your rotor size, which would reduce that heat build-up. Also, you mention that you have resin pads; you might want to think about using sintered (aka metallic) pads instead, because these are a little more resistant to heat, although you may lose some initial bite. Finally, it’s worth a look at your braking technique to see whether you’re dragging the brakes a lot.
IN PLAIN ENGLISH
I’m looking at buying a Cannondale. The brand claim the bike has an ‘AI’ rear triangle. What is this, does it matter, and if so, why?
James Ruskin, via email
AI stands for ‘Asymmetric Integration’. On most bikes, the seatstays are symmetrical and the wheel is ‘dished’ (the spokes on the drive side extend straighter out of the flange than those on the non-drive side) to make room for the cassette.
Cannondale take the opposite approach, making the rear triangle asymmetrical instead of the wheel. The hub and drivetrain are shifted 6mm to the right, while the rim is centralised over the hub. In theory this gives a stiffer wheel build for a given spoke type and spoke count. It also allows use of shorter chainstays. On a complete bike, this approach shouldn’t cause any problems. However, if you wish to upgrade the cranks or rear wheel down the line you’ll have to make sure they’re compatible and will likely need to re-dish (re-centre) the wheel if it’s not AI-specific.
clutching at straws
My Shimano XT clutch mech has become quite stiff. I’ve been dropping the chain a lot, and it takes a fair bit of force to push the mech forward so I can put the chain back on the chainring. Does it just need a good clean or could the spring have gone (it’s four years old)? Lee Norton, via email
It’d be unusual for the spring to have gone, and for that to cause the issue you’ve described. As such, it’s likely dirt or a clutch issue that needs sorting out. You should be able to strip the mech down and have a look. Take care doing so, though, because small parts can spring out at you, and they’ll all need replacing exactly where they originally were. Give everything a gentle clean with Muc-Off Bio Degreaser or similar, add fresh grease where needed, and nip it all back together again. As a side note, if your mech is several years old, it’s worth checking the jockey wheels for wear – they could be due a refresh, which may also help improve your shifting.