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

New: Take part in the September Giveaway for a Spider Rear Rack and a Heavy Duty Drybag from aeroe


Awkward bolts!
#1
Been trying to remove the cranks in order to replace the bottom bracket, after much effort I managed to remove one side, however despite being careful the thread inside the other one has 'rounded-out', meaning the allen key just spins round. There's not much room to drill a bigger hole or anything like that, but I can't figure out how to remove the darn thing now. Any ideas?
Cheers
Return of the Mech
  Reply
#2
Photos would be a big help here.

I think you are trying to remove the crank bolt , that's the only allen head I can visualize.
Never Give Up!!!
  Reply
#3
Yes that's right - I'll aim to post some photos shortly
Return of the Mech
  Reply
#4
[attachment=4256][attachment=4257]
Return of the Mech
  Reply
#5
Cannot tell too much from photos but at least we know what bolt you are talking about. Spray some good penetrating oil in there , do not know where you are so do not know brands, put bicycle on side and let the bolt soak overnight.
There are abrasive compounds you can put into the bolt head and that would help the allen wrench grab. Otherwise you can use a small sharp cold chisel maybe even a screwdriver that fits tightly and need to be forced in with taps from hammer than grab that with a wrench or pliers and try that. You do have a crank puller?
Once the bolt is mangled its pretty much a destracto job to get it out.

You could also drill the head off if the above fails. Just drill straight in till the head can be collapsed. You can use progressively bigger drill bits.Not fun...
Never Give Up!!!
  Reply
#6
Use a big bolt extractor... Use a Vise-Grip with it...

http://m4.uxcell.com/photo_new/20080929/c/ux_a08092900ux0077_ux_c.jpg
  Reply
#7
(06-17-2013, 07:55 PM)bobtravers Wrote:  Use a big bolt extractor... Use a Vise-Grip with it...

http://m4.uxcell.com/photo_new/20080929/c/ux_a08092900ux0077_ux_c.jpg

Yes easy out will work too, if you have a set . You first need to drill a center hole screw easy out in clockwise and unscrew bolt CCW. They are very hard therefore easy to break . No side forces.

Since you have the other bolt out that would give you an idea of how big an easy out you need. Smaller than the bolt.
Never Give Up!!!
  Reply


Possibly Related Threads...
Thread
Author
Replies
Views
Last Post
 
4,254
10-07-2012, 11:00 AM
Last Post: Bill
 
8,122
12-30-2009, 07:11 PM
Last Post: DaveM

Forum Jump:

[-]
10 Latest Posts
Know about the Hercules?
Yesterday 11:04 PM
Where are you from and What is your favo...
Yesterday 10:19 PM
Pedals: Clip vs. Clipless
Yesterday 07:48 PM
Raleigh "Trail" bike
Yesterday 05:41 PM
Wobbling freewheel
Yesterday 09:46 AM
Campagnoli seat post ID
09-16-2020 05:41 PM
Tour de France 2020
09-16-2020 07:43 AM
Drivetrain Problem!
09-15-2020 07:29 PM
Rebuilding an old Rockshox SID XC
09-14-2020 08:04 PM
Hi folks!
09-14-2020 11:02 AM

[-]
Top 5 Posters This Month
no avatar 1. Jesper
34 posts
no avatar 2. G_M
15 posts
no avatar 3. Sagan97
10 posts
no avatar 4. Papa Dom
10 posts
no avatar 5. Painkiller
9 posts