Retrobike Forum Index

It is currently Thu Dec 08, 2016 7:46 pm

* Login   * Register * Search  * FAQ



Post new topic Reply to topic  [ 20 posts ]  Go to page Previous  1, 2
Author Message
PostPosted: Tue Oct 08, 2013 1:43 pm 
Dirt Disciple

Joined: Tue Sep 17, 2013 7:06 pm
Posts: 46
The headset was well and truly wedged in this one, even, with the expansion from the crack, so i think an oversize headset being wedged in might be the answer fro this one- I measured the headset and it was just over 1 1/8

jimo746 wrote:
dyna-ti wrote:
Now we've established they have a tendency to crack in the headtube the question we must be asking is why? :?

Suspension fork ? Rough riding ? Must be some common denominator :?



This isn't a problem reserved for Pace frames though, plenty of other manufacturers produced aluminium frames which also seemed prone to cracking at the head tube, amongst other places.

Maybe the type, grade, and thickness of the aluminium used is the issue? The fact that the RC300 came with a butted head tube also says quite a lot about the construction of the head tube itself.

And lets not forget the finite fatigue life of aluminium alloys as opposed to steel or Titanium.

I do think there is an element of user error or abuse in some cases though. The Pace frames were designed for XC/ race use, so getting "insane" air or hitting "gnarly" drop-offs is perhaps exceeding the design parameters of the frame, pretty much any frame will break if you drop in from a sufficient height.
And the increasing travel of suspension forks no doubt contributes to both the abuse the frame takes, and the stresses put on the headtube on a daily basis.


Top
 Profile  
 
PostPosted: Tue Oct 08, 2013 2:13 pm 
Old School Grand Master
User avatar

Joined: Wed Apr 12, 2006 12:33 pm
Posts: 11105
Location: The Home Of Mountain Biking, And All Great Things.
Repairable or not I wouldn't get into it. The seller could not possibly have been unaware of that crack, I would return it. Rare that size may be, one will turn up sooner or later. Unless the seller gives you a refund of an amount that would make it 'economic' of course.


Top
 Profile  
 
PostPosted: Tue Oct 08, 2013 2:18 pm 
Retro Guru

Joined: Wed Aug 07, 2013 7:24 pm
Posts: 303
Location: New Brunswick, Canada
I've seen lots of top/downtube and weld failures from fatigue, but just about every cracked head tube I've ever seen was from incorrect installation of headsets. Allow one to "cock" as it's pressed in, and it's "all over". One of those "simple little jobs" that can easily end a frame.

J


Top
 Profile  
 
PostPosted: Tue Oct 08, 2013 9:27 pm 
retrobike rider
retrobike rider

Joined: Thu Apr 17, 2008 1:24 am
Posts: 7563
Location: Manchester
Mijbil wrote:
The headset was well and truly wedged in this one, even, with the expansion from the crack, so i think an oversize headset being wedged in might be the answer fro this one- I measured the headset and it was just over 1 1/8


It has to be oversize or it would fall out. From memory 1.1/8" headset cups are 34.3mm. It needs to be tight also to stop rotating.
Likely to be poor fitting practise!


Top
 Profile  
 
PostPosted: Tue Oct 08, 2013 9:45 pm 
BoTM Winner / Gold Trader / Rider
BoTM Winner / Gold Trader / Rider
User avatar

Joined: Fri May 15, 2009 2:21 pm
Posts: 1400
Location: The Flatlands
highlandsflyer wrote:
Repairable or not I wouldn't get into it. The seller could not possibly have been unaware of that crack, I would return it. Rare that size may be, one will turn up sooner or later.

++++1. Why buy something you have really wanted, only to find it is damaged. Why would you want to get it repaired when you will be much happier with a straight undamaged frame, even if it takes a little while longer to source.
Pack it up, send it back and keep those eyes peeled for a replacement

Cheers.......Nick


Top
 Profile  
 
PostPosted: Wed Oct 09, 2013 1:10 pm 
Old School Grand Master

Joined: Tue Oct 09, 2007 1:55 pm
Posts: 8219
Location: New Forest, UK
dyna-ti wrote:
Now we've established they have a tendency to crack in the headtube the question we must be asking is why? :?

Suspension fork ? Rough riding ? Must be some common denominator :?


It's a fatigue crack. Most likely is that it is too thin, so the fatigue life is short. Poor finishing with nicks and grooves which act as stress raisers doesn't help. Make any frame of any material thin enough and it will happen.


Top
 Profile  
 
PostPosted: Wed Oct 09, 2013 1:16 pm 
Gold Trader
Gold Trader
User avatar

Joined: Fri Jan 23, 2009 2:30 pm
Posts: 12436
Location: Surrey
My f3 frame is much thicker at the head tube than most, if not all bikes I own made from aluminium. I could be wrong of course but I doubt it is too thin.


Top
 Profile  
 
PostPosted: Wed Oct 09, 2013 1:18 pm 
retrobike rider / Gold Trader
retrobike rider / Gold Trader
User avatar

Joined: Sat Aug 15, 2009 4:16 pm
Posts: 4282
Location: Perfect Sound Forever
Looks like the headset is not square to me... poor fitting will have caused this crack... is my guess.

and yes... get your money back and await a better one - or at least a massive discount.


Top
 Profile  
 
PostPosted: Wed Oct 09, 2013 7:33 pm 
Dirt Disciple

Joined: Tue Sep 17, 2013 7:06 pm
Posts: 46
Thanks for all the advice everyone, I've decided to send it back as I don't want the hassle of the repair, or a chunk of weld staring me in the eye every time I ride to remind me I should have been more patient, or not feeling confident to push it on the trail and then stopping riding every 5 minutes just to check!

As luck would have it I'm off to view and hopefully bring home another 16.5 tomorrow!! :D :D


Top
 Profile  
 
PostPosted: Wed Oct 09, 2013 11:16 pm 
Old School Grand Master
User avatar

Joined: Wed Apr 12, 2006 12:33 pm
Posts: 11105
Location: The Home Of Mountain Biking, And All Great Things.
Nice one! I think you did the right thing. I would advise a nice steel frame anyway, old Al is never a great long term option.


Top
 Profile  
 
Display posts from previous:  Sort by  
Post new topic Reply to topic  [ 20 posts ]  Go to page Previous  1, 2

All times are UTC [ DST ]


Who is online

Users browsing this forum: cherrybomb, grarea, jez-4-bikes-max, jimo746, Maxipedia, mkone, Retro junkie, shawnb, Yahoo [Bot] and 51 guests


You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot post attachments in this forum

Search for:
Jump to:  

About Us

Follow Retrobike

Other cool stuff

All content © 2005-2015 Retrobike unless otherwise stated.
Cookies Policy.
bikedeals - the best bike deals in one place
FatCOGS - Fat Chance Owner's Group

Powered by phpBB® Forum Software © phpBB Group