Have questions or want to discuss cycling? Join Now or Sign In to participate in the BikeRide community.

New: Take part in the June Giveaway for NAKTO Camel e-bike worth $739


Crankset keeps on unscrewing
#1
Hello,
My bike as a M443 Shimano (low end) crankset , with a Deore front derailleur and a Deorre XTR rear derailleur.
The crankset doesn't stay screwed on. every 50/100km I have to fix it. Any body has an idea about what I may want to do ?
As a side question, my crankset is secured in the opposite rotating direction, so when I ride it is normal that I slowly free it, is it normal ?
Thanks in advance

  Reply
#2
I'm not 100% sure if you mean that the crank arms are coming loose or that the bottom bracket (BB) is unscrewing itself out of the frame.
If the crank arms, it could either be that you are just not tightening them enough (I'd recommend finding a shop that can tighten them with a torque wrench to get it right. Or it could be that the arms are damaged and may need to be replaced.
But I think you mean that the BB is coming loose. Again, it could be that you just aren't getting it tight enough, but these don't really need to be cranked down that hard. Is it coming loose just on one side? Some lower end BBs have a plastic cup on one side and that cup can get mashed out of shape. This will allow a little bit of movement in the BB as you pedal which could cause the cup to unscrew. You may be able to just replace the cup.
On the drive side, I think it is always metal threads which shouldn't have this problem unless the threads are completely stripped.
If you can't see any obvious damage, you could try a little locktight on the threads. But nothing too permanent, you will need to remove this someday. Otherwise, either try replacing the plastic cup or whole BB. The drive side of the BB has reversed threads (rightly loosey), the left side is normal threads. This is standard.

  Reply


Possibly Related Threads...
Thread
Author
Replies
Views
Last Post

Forum Jump:

[-]
10 Latest Posts
Electric Bike Safety Tips
Today 04:05 AM
ZULIANI Oria 'helical' tubing 80s
Today 01:37 AM
Rode my First Double Century in June
07-01-2022 10:50 AM
NAKTO Giveaway June 2022
06-28-2022 03:52 AM
NAKTO GIVEAWAY
06-28-2022 12:16 AM
2022 road cycling season
06-27-2022 02:31 PM
OnGuard K9 Folding Plate Lock
06-27-2022 10:38 AM
Bike for commuters
06-27-2022 05:50 AM
Rim replacement for Old Cosmos SuperCors...
06-26-2022 11:24 PM
What was your first bicycle?
06-26-2022 07:18 PM

[-]
Join BikeRide on Strava
Feel free to join if you are on Strava: www.strava.com/clubs/bikeridecom

[-]
Top 5 Posters This Month
no avatar 1. Jesper
19 posts
no avatar 2. ReapThaWhirlwind
8 posts
no avatar 3. Yevhen
8 posts
no avatar 4. Munich Transfers
7 posts
no avatar 5. aliccon
7 posts