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I've got an old `86 Raleigh fixed gear bicycle that is making a loud clicking noise when the cranks rotates. It seems to have just started doing this today. I'm looking for someone who, maybe has experienced this type of noise with a bike before, that can possibly point me in the right direction to fixing it.

Both bolts on each side are stripped so I'm not sure how I'd get it apart to see if it could be the bottom bracket, if you have any ideas on how to do that, that's appreciated too.

The only thing that I can think of that could possibly be a variable in this is yesterday I sprayed some pb blaster down my seat post and into a little hole in the frame to get my extremely stuck seat to come loose.

Anyway...here's a video of the noise:

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    There are a half-dozen possible causes, but the somewhat irregular nature of the sound suggests it has something to do with the chain or chainrings. First check that the chainring bolts are tight. Oh, and to eliminate several other possibilities give each crank arm a good shake, looking for any looseness at the crank arm to shaft connection or between the crank shaft and the bearings. And maybe you can send a small mouse down there to get the PB out! Apr 10, 2019 at 2:20
  • chainring bolts are very tight, i took the chain off and its still making the noise, no looseness in the crank arms
    – m4rsi
    Apr 10, 2019 at 2:29
  • (I'll note that this doesn't appear to be a "fixed gear" bike, since I see two chainrings. And your problem may be somehow connected to the fact that the bike was somewhat clumsily painted at some time in the past. Paint may have gotten into the bearings.) Apr 10, 2019 at 2:30
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    Does it make the same noises if you pedal forward too?
    – Criggie
    Apr 10, 2019 at 6:33
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    Why the heck has this got a downvote? Question is clear and a video is included that clearly demonstrates the problem. Apr 10, 2019 at 17:14

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That sounds like the bottom bracket bearings to me.

It could be the chain, but you can eliminate that by loosening the rear wheel and slipping the chain off the chainring.

It's not chainring bolts as these only creak under load. It's not the bottom bracket cups for the same reason.

You appear to have a loose ball bearing bottom bracket with an axle with square tapers that the cranks fit onto. I linked a video below that shows how to service this type of bearings. When you say 'Both bolts on each side are stripped' I think you mean the end-caps. You should be able to get those off by jamming something that will engage with the rounded off hex hole. I'd try a large screwdriver with a tapered head.

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  • But, as I indicated earlier, getting the thing apart requires some specialized tools and at least modest mechanic's skills. Apr 10, 2019 at 18:04

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