Thorn Cycles Forum

Technical => General Technical => Topic started by: rflynnr on February 03, 2017, 11:25:52 AM

Title: Advice on removing older eccentric bottom bracket
Post by: rflynnr on February 03, 2017, 11:25:52 AM
Hi,

I have an older Thorn Me N U2 (and by older I mean up to 15 years old). One of the eccentric bottom brackets has seized (and I mean seized beyond all efforts to loosen it). However the effort of attempting to get it to move has worn away at the holes used to turn the bracket within the frame and I need to replace it. (It looks like this https://www.sjscycles.co.uk/bottom-brackets/eccentric-bottom-bracket-insert-taiwanese-fits-thorn-voyager-explorer-tandems-etc/ (https://www.sjscycles.co.uk/bottom-brackets/eccentric-bottom-bracket-insert-taiwanese-fits-thorn-voyager-explorer-tandems-etc/)incidentally.) Given my location it looks like I'll have to do the job myself. But my question is: can the EBB be removed simply by loosening the two frame bolts or is there some additional mechanism controlling lateral movement (to prevent the bracket moving sideways while in the frame)? If so, what and where is it?

Thanks in advance
Title: Re: Advice on removing older eccentric bottom bracket
Post by: Peter_K on February 03, 2017, 02:12:26 PM
On my newer Thorn Nomad there is no such "additional mechanism controlling lateral movement". It can easily be removed by unscrewing the two frame bolts.

I have two frames with excenters from other manufacturers, and those excenters can also be removed after loosening the bolts.

So I guess that will also be the case with your Thorn Me N U2.
Title: Re: Advice on removing older eccentric bottom bracket
Post by: Javier on February 03, 2017, 06:46:52 PM
@rflynnr,
If I were you I would ask SJS mechanics, they know the stuff and they are very helpful.
Regards
j
Title: Re: Advice on removing older eccentric bottom bracket
Post by: rflynnr on February 05, 2017, 12:18:54 PM
Hi guys, thanks for the advice - both of which I took. SJS recommended a gentle tap with a mallet which did the trick.
Title: Re: Advice on removing older eccentric bottom bracket
Post by: jags on February 05, 2017, 08:16:29 PM
is there such a thing as a gentle tap with a mallet ;D ;D
glad it worked tho.


jags.