Seatpost quandary

dimmockg

Needing a post with bit of layback for my hopper expert, was pretty much settled on Thomson elite, but wonders I there were any others out there of similar price or spec?

Seen:

Cobalt 2
Cobalt 3
Nuke proof warhead layback
Easton (ea70 irrc)

Anything considered around same weight and price as Thomson,

Is the Thomson the pick of the bunch?

Needs to be 30.9 x 350 approx

supersonic

What bike is it for and how much do you weigh? Is light weight a priority?

dimmockg

For my rockhopper expert and I weigh approx 11st 8lb

Light(ish) weight would be nice but not the be all and end all

supersonic

Pity it's a 30.9, as this is a great buy:

http://www.carboncycles.cc/?s=0&t=2&c=47&p=798&

Unless you shim it.

But this would be my choice:

http://www.ukbikestore.co.uk/product/61 ... tpost.html

Tough, decent price, decent weight.

dimmockg

funny enough id just literally read up on the 2nd post in the bike and gear section here, seems like it could be a winner, had also checked the exotic stuff but would need a shim as rightly pointed out

supersonic

Koryak is great stuff, have a set of bars. Tough, light and stiff, and a good price, no point getting Thomson.

Bike-Rich

Got a few saddle questions if ok and thought i'd ask here.
I need to replace mine as it does not fully go to the bottom of the post. I need it to go right down as at the moment the ride height is too high.

Are there 2 main sizes to seat posts? 1 for raod bikes (thinner) and 1 for mtb?

supersonic

Many sizes of seatpost, both used on road and MTB. Most common are 31.6 and 27.2 - it should be wrote on the side of the post somewhere.

Or cut some off the bottom of your post. Though you must ensure at least 3 inches is in the frame.

Bike-Rich

supersonic wrote:

Many sizes of seatpost, both used on road and MTB. Most common are 31.6 and 27.2 - it should be wrote on the side of the post somewhere.

Or cut some off the bottom of your post. Though you must ensure at least 3 inches is in the frame.

Thanks

I have a cannondale ultra and I am sure it is 31.6 but will see if current post has any writing on.

I am also keen on that post you pointed out - if you were to recomend a saddle - what would you choose?

Do most people when replacing or upgrading parts stick with the stock spec i.e only buying cannondale parts for a cannondale bike - or are these aftermarket parts better?

supersonic

You can mix and match parts - best thing is to weigh what you have, as lighter is often why people upgrade.

Saddles are personal preference, but I like the Fizik Gobi series.

Bike-Rich

supersonic wrote:

You can mix and match parts - best thing is to weigh what you have, as lighter is often why people upgrade.

Saddles are personal preference, but I like the Fizik Gobi series.

Many thanks,

I have noticed some posts are straight all the way to clamp, whilst other have a small or sometime medium 'curve' at the top. Is one type suited for a certain bike - which would you say is the best.
Picture below is a straight post:

supersonic

One gives you 'layback' ie puts the saddle further back. Is what fits best really, but putting your weight too far back can upset weight balance. They are often used for bikes that don't fit properly.

Bike-Rich

Thanks for reply,

I think i am going to go with straight (or similar to the koryak you posted).

I just checked my old seatpost and there is no size info on it. I used a micrometer on the saddle post and it seems I have a 30.9. Is this an uncommon size. I have a Cannondale Ultra and I cannot find the specified size from a google search - does 30.6 sound right to you?

Kind regards,

njee20

30.9 is a fairly common size - all Specialized mountain bikes, certain Santa Cruz, Titus, Intense and Giant frames off the top of my head. Shouldn't prove problematic. 30.6 isn't common at all.

I'd disagree with SSs comment on layback posts countering an ill-fitting bike, it's a function of your leg length and all about fit. You could say inline posts are for bikes that are too short.

No point in upgrading if you just want a shorter seatpost - just cut yours down, you'll likely have to do the same with a new one anyway. What exactly are you trying to achieve?

The Rookie

A lot more OE seatposts use setback clamps than use inline in my experience.
All it does is change the effective seattube angle (and top tube length), even that can be corrected back to an extent if you run the saddle forward of central by a bit.

Simon

Bike-Rich

njee20 wrote:

No point in upgrading if you just want a shorter seatpost - just cut yours down, you'll likely have to do the same with a new one anyway. What exactly are you trying to achieve?

The seatpost that came with my bike has quite a large 'curve/lay back' meaning I cannot lower it any more. Bike is ridable but not fully comfortable. If I could get a straight post and lower saddle I think it would be much better.

Just thought i'd add this, I presume I am taking the sizes right going from outside - outside diameter? Does it look like a 30.9 to you?



Many thanks,

supersonic

I'd disagree with SSs comment on layback posts countering an ill-fitting bike, it's a function of your leg length and all about fit.

I didn't mean for everyone - but there seems to be quite a few people who get bikes that are too small, then combat it with large layback seatposts and the saddle rammed far back, placing their weight too far behind the BB. This upsets front end grip. Fine if you want it like that, but is something I (and Steve Worland) have seen a lot.

supersonic

Bike-Rich wrote:

njee20 wrote:

No point in upgrading if you just want a shorter seatpost - just cut yours down, you'll likely have to do the same with a new one anyway. What exactly are you trying to achieve?

The seatpost that came with my bike has quite a large 'curve/lay back' meaning I cannot lower it any more. Bike is ridable but not fully comfortable. If I could get a straight post and lower saddle I think it would be much better.

Just thought i'd add this, I presume I am taking the sizes right going from outside - outside diameter? Does it look like a 30.9 to you?



Many thanks,

Lets have a pic of the bike with the seatpost in the normal position.

njee20

Well yes, running the saddle as far back as possible on a layback post is daft, but to link that directly to the use of layback posts is quite a leap.

The seatpost that came with my bike has quite a large 'curve/lay back' meaning I cannot lower it any more. Bike is ridable but not fully comfortable. If I could get a straight post and lower saddle I think it would be much better.

Just thought i'd add this, I presume I am taking the sizes right going from outside - outside diameter? Does it look like a 30.9 to you?

I'd not trust a tape measure in the least. Are you sure there's nothing stamped on the post? Not printed, actually embossed?

If you have a layback post and it won't go low enough it sounds like the frame could be too big, as SS says do you have a photo as you ride it?

Bike-Rich

njee20 wrote:

I'd not trust a tape measure in the least. Are you sure there's nothing stamped on the post? Not printed, actually embossed?

Just had another look and it does have a faint size printed on it, it's 31.6 so i guess you were proved right about not trusting a tape. I was surprised at that as I thought it was definitely a 30.9.

njee20 wrote:

If you have a layback post and it won't go low enough it sounds like the frame could be too big, as SS says do you have a photo as you ride it?

Yes it is slightly to big, I bought the bike from a friend who is 3-5" bigger then me. Bike is only slightly too big though, i think if I could reduce saddle height all would be ok.
I'll get some pics up of saddle fitted to bike later, only took saddle with me this morning as i wanted to measure in work.



The white arrow indicates the point the saddle stops going down.

nicklouse

then the bike is way way too big for you.

The Rookie

+1, if you want the seatpost lower than that, the frame is too big! most MTB's will have circa 6" of seatpost showing, maybe a bit more.

Simon

Bike-Rich

nicklouse wrote:

then the bike is way way too big for you.

I think you could be right actually, the frame is large so I guess there is not much to be done about that.
I might pass it onto a taller relative who is in need of a bike.

What would you say the average size needs to be of the showing post on any bike?

bails87

Depends on the bike and the person. Get a bike that fits, across the top of the bike, then adjust the seatpost to make the height right.

I'm near-as-makes-no-difference 6 foot, ride an 18" frame with my seatpost pretty close to the minimum insertion line, I think it's 28cm from the seatpost clamp to the saddle rails.