Bicycle Mechanics - 30.9 seatpost in 30.8 Specialized

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View Full Version : 30.9 seatpost in 30.8 Specialized


Lightspeed
10-08-04, 09:47 PM
Will this work. There seem to be a lot more 30.9 seatpost for sale than 30.8. I'm hoping I can squeeze one in.


Raiyn
10-08-04, 10:10 PM
I don't know where you got that the30.8 number from but the Specialized MTB's use a 30.9 seatpost and the road bikes use a 27.2. So in a nut shell yeah using a 30.9 will work fine.

seely
10-08-04, 11:30 PM
If you want a Thompson Elite Setback post, brand new in the bag, 30.9, 367mm, let me know, I will let it go for cost basically.


Raiyn
10-08-04, 11:33 PM
If you want a Thompson Elite Setback post, brand new in the bag, 30.9, 367mm, let me know, I will let it go for cost basically.
Hell I'm tempted But I'd need the full 400 :D

Lightspeed
10-09-04, 12:27 PM
The Specialized specs say 30.8.

Lightspeed
10-09-04, 12:29 PM
I don't know where you got that the30.8 number from but the Specialized MTB's use a 30.9 seatpost and the road bikes use a 27.2. So in a nut shell yeah using a 30.9 will work fine.

Thanks for the info. I'm new to this mountain bike stuff. Where I come from everything is pretty much 27.2.

cryptid01
10-09-04, 05:10 PM
The Specialized specs say 30.8.

Must be a typo.

Who's sweating a tenth of a millimeter anyway? :p

Scooby Snax
10-09-04, 07:20 PM
Must be a typo.

Who's sweating a tenth of a millimeter anyway? :p

...... somewhere far far away, an engineer just had a shiver run down his back....

Scooby Snax
10-09-04, 07:23 PM
If you want a Thompson Elite Setback post, brand new in the bag, 30.9, 367mm, let me know, I will let it go for cost basically.
Tempting... very tempting...

Whadaya say cost is.....?

Derek
10-09-04, 09:34 PM
"The Specialized specs say 30.8."

What bike is it?

Derek
Think

Lightspeed
10-09-04, 09:56 PM
"The Specialized specs say 30.8."

What bike is it?

Derek
Think

Stumpjumper. a few years old has 8 speed parts.

EastKY
10-10-04, 07:40 AM
Thanks for the info. I'm new to this mountain bike stuff. Where I come from everything is pretty much 27.2.

Don't know "Where I come from" is, but if you can dial an 800 number, you can get a 30.8 MTB Suspension seatpost from Bike Nashbar, regularly sales for $29.99, now on sale for $19.99. Part no. is NS-SSP2-30.8

I am not associated with Bike Nashbar in any way, shape or form. I just happened to order one for my Giant just this week.

Derek
10-10-04, 07:54 AM
"Stumpjumper. a few years old has 8 speed parts."

I have a 2004 Stumpjumper and the seatpost is a 30.9mm. I wonder if Specialized changed the size of the tube in their newer frames or if it is a typo as was already suggested. Try contacting Specialized just to make sure it is a .8 and not a .9.

Derek
Think

EastKY
10-10-04, 07:59 AM
You know, after posting that about Bike Nashbar, I remembered Sheldon Brown's site has lots of seatpost info. Here's the link http://www.sheldonbrown.com/seatpost_sizes.html#s or even better yet, if you've access to a decent set of metric calipers, remove the seat post and meaure it or the downtube inside diameter.

jstream
10-10-04, 09:19 AM
Check your existing seatpost. The size may be stamped on it somewhere.

Raiyn
10-10-04, 10:28 PM
The Specialized specs say 30.8.
...and where does it say that? In the owners's manual? I'm curious because Specialized has been using 30.9 seatpost seemingly since the dawn of time, certainly since they started using 8 speed parts on Stumpy's.

Scooby Snax
10-11-04, 07:38 AM
Lightspeed, My Stumpy is 30.9, Either way, I have one that has about 7 or 8" of useable seatpost. pay for the postage and its yours. PM me if you're interested.

Lightspeed
10-12-04, 02:01 AM
...and where does it say that? In the owners's manual? I'm curious because Specialized has been using 30.9 seatpost seemingly since the dawn of time, certainly since they started using 8 speed parts on Stumpy's.

I'm sniffing a little elitism here. Before I posting I double checked by measuring myself. 30.8 (digital calipers).
I posted here to find out. I don't mind being wrong. I've been taking apart and assembling bike since about 1970 and have built and custom painted 100's of bikes. Almost all road racing bikes, so that's why I was unfamiliar with the odd size posts that seem to be common on MTB's. Odd sizes (not 27.2) are still mostly rare on road bike with the exception of carbon and Tri frames. I'd rather try to make a smaller post work than a larger one.
There, so now you know the whole story.

Lightspeed
10-12-04, 02:05 AM
Anyway, anyone know where to get a USE XCR Shockpost rebuild kit? The one I have wobbles and that's why I was thinking change. I need some setback also and the older 2 bolt clamp on my XCR has no setback.

Raiyn
10-12-04, 12:33 PM
I'm sniffing a little elitism here. Before I posting I double checked by measuring myself. 30.8 (digital calipers).
I posted here to find out. I don't mind being wrong. I've been taking apart and assembling bike since about 1970 and have built and custom painted 100's of bikes. Almost all road racing bikes, so that's why I was unfamiliar with the odd size posts that seem to be common on MTB's. Odd sizes (not 27.2) are still mostly rare on road bike with the exception of carbon and Tri frames. I'd rather try to make a smaller post work than a larger one.
There, so now you know the whole story.No not eliteism, just someone who's been dealing with / working on Specialized bikes for quite a while and knows the sizes commonly used by them.

spinbackle
10-12-04, 06:23 PM
Use the 30.9 seatpost. I've got an older Stumpy with a 27.0 seattube and a 27.2 Thomson seatpost in it. Just lube it up real good and stick 'er in.