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Yesterday while out on my daily exercise (I live in London) I had to cycle through a pothole (bus too close behind so couldn't swerve or stop) that jolted the whole bike. I then noticed a rattling sound from the bike on the rest of the ride, although it seemed to be handling normally (gears, steering, brakes). Nothing is obviously loose. Given that there aren't any open cycle shops near us, is there any way to check what is damaged on the bike with limited tools and experience? Will it be safe to continue cycling on? The bike is a Trek Domane SL 5 2019.

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    Look the frame over closely for cracks. Apr 12 '20 at 12:15
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    Clean the bike, hang it up off the ground, and inspect it closely for the cause of the rattling. If it goes away when you stop pedalling, its related to the chain/transmission. If its always there when coasting then cause is more general. If the sound changes as you brake, it might be wheel/rim/brake related, or rotor if you have them.
    – Criggie
    Apr 12 '20 at 12:43
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    Unrelated - this might have been avoidable if you were able to bunny-hop. Do please report this pothole to whatever local roading authority is responsible for your area.
    – Criggie
    Apr 12 '20 at 12:44
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    Maybe bunny hopping a pothole on short notice isn't feasible for many cyclists, but you could definitely attempt to unweight the saddle next time, i.e. get your butt just off the saddle. Cyclists often do this when riding over minor bumps or train tracks. It would reduce the impact to the bike.
    – Weiwen Ng
    Apr 12 '20 at 15:25
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    One though is bottle holder bosses.
    – mattnz
    Apr 13 '20 at 2:01
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CFC frames are not as fragile as many people seem to think they are. If you got a heavy jolt but didn't feel like you were going to be thrown off the frame is probably fine. I'd be more immediately concerned about the wheels than the frame, and that may be the source of the rattle.

You can examine the frame closely looking for cracks. If it's dirty clean it first. Using a bright light will help.

Is the rattle coming from the drive train? Does it happen when pedalling only? Does it happen when coasting? Or does it happen when you go over a bump and seems to be something loose on the bike? If the latter, a good way to track it down is to pick the bike up and bounce it on the ground fairly hard on it's tires. By carefully listening you can track the noise down. Trying to locate a source of a rattling noise is almost impossible when actually riding.

Check your wheels are running true. Check spoke tension by systematically going around the wheel pinching pairs of spokes. You may have a spoke broken at the nipple end that is hanging on in the rim.

It's a good idea to learn some bump-mitigation techniques. for smaller bumps raise your butt off of the seat, keep your knees bent and absorb some of the impact. For bigger bumps it's useful to know how to pull off even a small bunny-hop.

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    Agree. It’s definitely possible to damage the frame, but it would have to be a massive hole. Also, if the frame were damaged, it’s likely the wheels would be damaged as well. Probably severely so.
    – Weiwen Ng
    Apr 12 '20 at 13:37
  • To add to Weiwen's comment, I think if damage to your frame was bad enough to hear a rattle, you would see some obvious damage. On the other hand you might have a slight warp in a rim that makes a spoke loose, and it wont necessarily be different looking than the spokes next to it.
    – bradly
    Apr 12 '20 at 14:20
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    Yeah, the rattle could very well be a broken spoke. Apr 12 '20 at 14:41
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    @DanielRHicks Or a loose rim sleeve Apr 12 '20 at 16:06
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If your bike has internally routed cables it could be the 'plugs' from those which were unsettled from the jolt. Could also be the internal part of a bottle cage m

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