Trek roscoe 8 2019 chainring removal.

Howie1987

I'm trying to remove my front chainring. Removed the bolt on the left side and according to the video i'm watching https://youtu.be/bO5SaLkRhO0 that should remove the arm. But not on mine it isnt budging. There also seems to be an bolt in drive side aswell which there isn't in the video.

Fyi i've never fixed anything on a bike so i'm a complete novice haha.

Not wanting to break the bike so playing it safe before i take a hammer to it.

whyamihere

The video shows a GXP chainset - The axle is part of the crank arm, and goes through the bottom bracket. Unfortunately, that's not what you've got. You have what looks to be an ISIS bottom bracket, where the axle is part of a separate bottom bracket, and the arms tighten onto that. To get the crank arms off, you need a crank arm extractor. This screws into the threads you see in your picture, and then part of it presses against the bottom bracket axle to pull the crank arm off. Something like this: www.wiggle.co.uk/x-tools-crank-extractor-1

I do also note that the video shows the changing of a direct mount ring. I would advise checking that you actually have a direct mount ring. A photo of the other side would be useful to check that this is what you actually have.

Howie1987

whyamihere wrote:

The video shows a GXP chainset - The axle is part of the crank arm, and goes through the bottom bracket. Unfortunately, that's not what you've got. You have what looks to be an ISIS bottom bracket, where the axle is part of a separate bottom bracket, and the arms tighten onto that. To get the crank arms off, you need a crank arm extractor. This screws into the threads you see in your picture, and then part of it presses against the bottom bracket axle to pull the crank arm off. Something like this: http://www.wiggle.co.uk/x-tools-crank-extractor-1

I do also note that the video shows the changing of a direct mount ring. I would advise checking that you actually have a direct mount ring. A photo of the other side would be useful to check that this is what you actually have.

Cheers mate. Thats exactly what i needed. Took it to halfords and they done it on the spot for a tenner. It was the correct chainring i had.

But least i know next time if i ever need to take it off. And i'll buy that tool also.

Cheers again.