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Technical & Reference Section => Tech and Restoration => Topic started by: oldschoolace on April 28, 2015, 08:14 PM

Title: More seatpost woes! Is there another sizes besides 7/8ths and 13/16th?
Post by: oldschoolace on April 28, 2015, 08:14 PM

This fookin vitus has me stumped lads. After finding a glassfibre post lodged in the bottom of it the other day I gave the seat mast a good scrub and a going with a tube honer. Clean as a whistle now.  :daumenhoch:

tried the cleaned up Gt post back in it today and it was still tighter than you would expect and wouldn't go much further past the keyhole slot.

I assumed as its French double butted tubing and that it has a glassfibre post lodged in it that it probably needs a 13/16th post but I reckon if I took the 1.6mm difference off the gt post it would rattle around in there like a Biro in a hooker  :-\

Is there another size im unaware of or is it deffo 13/16 or 7/8th

Title: Re: More seatpost woes! Is there another sizes besides 7/8ths and 13/16th?
Post by: Gnarlyscoots on April 28, 2015, 08:30 PM

Quote from: oldschoolace on April 28, 2015, 08:14 PM

13/16 or 7/8th

Is that 20.6 (21) and 22.2 mm yes  :whistle:

Title: Re: More seatpost woes! Is there another sizes besides 7/8ths and 13/16th?
Post by: oldschoolace on April 28, 2015, 08:34 PM

Yep that's right for you younger kids  :LolLolLolLol:

Title: Re: More seatpost woes! Is there another sizes besides 7/8ths and 13/16th?
Post by: Gnarlyscoots on April 28, 2015, 08:51 PM

Quote from: oldschoolace on April 28, 2015, 08:34 PM

Yep that's right for you younger kids  :LolLolLolLol:

;D

I think I am right, I may be just b**********g but, didn't GT make their posts different sizes, chrome and painted? If you remove the paint from a GT post it is slightly smaller than a chrome post. I think it was GT anyhow  :-\

Title: Re: More seatpost woes! Is there another sizes besides 7/8ths and 13/16th?
Post by: glenboy on April 28, 2015, 08:54 PM

Yep there's 22.8 as well

Title: Re: More seatpost woes! Is there another sizes besides 7/8ths and 13/16th?
Post by: Gnarlyscoots on April 28, 2015, 08:56 PM

Quote from: glenboy on April 28, 2015, 08:54 PM

Yep there's 22.8 as well

I think Clint means a post size in between 13/16 and 7/8 Glen  :)

Title: Re: More seatpost woes! Is there another sizes besides 7/8ths and 13/16th?
Post by: oldschoolace on April 28, 2015, 08:58 PM

I did wonder if the post was an oddball size Terry but I measured it with my digital calipers and was Bob on 22.2mm

Title: Re: More seatpost woes! Is there another sizes besides 7/8ths and 13/16th?
Post by: glenboy on April 28, 2015, 09:05 PM

Ah got it terry and yes  some gt  posts are 22.6mm for some weird reason so maybe you have one of them Clint

Title: Re: More seatpost woes! Is there another sizes besides 7/8ths and 13/16th?
Post by: glenboy on April 28, 2015, 09:20 PM

Easiest way if not is use a alloy or fluted alloy post and just sand it and polish it down a bit

Title: Re: More seatpost woes! Is there another sizes besides 7/8ths and 13/16th?
Post by: Bigfrawg on April 29, 2015, 06:38 AM

Or smash the coont in with a hammer

Title: Re: More seatpost woes! Is there another sizes besides 7/8ths and 13/16th?
Post by: snoopy72 on April 29, 2015, 07:09 AM

Shine a touch down the seat mast tube and make sure the weld from the top tube hasn't penetrated into the seat mast tube , I have had this before with a mongoose frame, once I carefully removed this tiny bump the seat post fitted perfectly all the way down the frame.

Title: Re: More seatpost woes! Is there another sizes besides 7/8ths and 13/16th?
Post by: oldschoolace on April 29, 2015, 12:58 PM

Seat mast is clean as a whistle. Doubled checked my measurements and the mast is 25.4mm diameter with a 1.6mm wall which would mean it should take a 22.2mm post  :-\

Gt post is deffo 22.2mm and its deffo round with no obvious dents, marks, anything that may make it a tight fit.
Really dont want to knock it in with a hammer  :-\

Might just find a 20.6 post and shim it with a pop can if need be

Title: Re: More seatpost woes! Is there another sizes besides 7/8ths and 13/16th?
Post by: bobbbbsy on April 29, 2015, 01:03 PM

clint we all use mm these days .  :LolLolLolLol:

the euros used it long before us to .

Title: Re: More seatpost woes! Is there another sizes besides 7/8ths and 13/16th?
Post by: CustardLips on April 29, 2015, 01:22 PM

Make a wooden one Clint.  :daumenhoch:
Then polish it to a mirror finish... no-one'll know.  :D

Title: Re: More seatpost woes! Is there another sizes besides 7/8ths and 13/16th?
Post by: chubby on April 29, 2015, 07:42 PM

(http://images.tapatalk-cdn.com/15/04/29/67ed19896d35f89aa940e24c30609cbe.jpg)

Still here if you need it chum 😊

Title: Re: More seatpost woes! Is there another sizes besides 7/8ths and 13/16th?
Post by: oldschoolace on April 29, 2015, 07:54 PM

Hey Hey almost forgot that beauty  :smitten:

Title: Re: More seatpost woes! Is there another sizes besides 7/8ths and 13/16th?
Post by: chubby on April 29, 2015, 08:07 PM

Quote from: oldschoolace on April 29, 2015, 07:54 PM

Hey Hey almost forgot that beauty  :smitten:

Just say the word  :teef:

Title: Re: More seatpost woes! Is there another sizes besides 7/8ths and 13/16th?
Post by: griff on April 29, 2015, 10:26 PM

Quote from: chubby on April 29, 2015, 07:42 PM

(http://images.tapatalk-cdn.com/15/04/29/67ed19896d35f89aa940e24c30609cbe.jpg)

Still here if you need it chum 😊

Fooking lol
There it is again

That reminds me, we need to have a think about sacrifices for the MK fire gods

Title: Re: More seatpost woes! Is there another sizes besides 7/8ths and 13/16th?
Post by: oldschoolace on April 29, 2015, 10:32 PM

NOOOOO! im half way through a display cabinet for this gem  :-X

Title: Re: More seatpost woes! Is there another sizes besides 7/8ths and 13/16th?
Post by: chubby on April 29, 2015, 11:13 PM

Don't worry, Griff threatened to burn it last year too