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Discussion Starter · #1 ·
I need a 30.9mm seatpost to go with the SC carbon blur that I am ordering but I can't decide what solution to go with!

1. Use my existing Thomson Masterpiece 27.2mm seatpost - reliable, reasonable weight - and look for a lightweight shim. Does one exist? I see that Extralite's 31.6 to 34.9mm weighs 22g - is there anything lighter than this for 27.2 to 30.9? Adding 22g to a ~190g seatpost is decidedly against WW principles.

2. Thomson Masterpiece 30.9
3. Easton EC90 Zero 30.9

These both have identical claimed weights - which is lighter in real life? weightweenies.starbike.com seems to suggest the Thomson is a little lighter. I have owned both these seatposts in different sizes, so I know they both perform well. The shock-dampening of carbon is probably superfluous seeing as this is going on a full susp. bike.

4. KCNC Ti Pro Lite

I rode this seatpost in 31.6 this year on my carbon hardtail. I LOVE the weight, but the clamp mechanism just does not perform. Am I doing something wrong? I have a short inseam so I push the seat forward on the seatpost. I tighten the bolts as best I can, but even with loctite by the end of a ride the saddle has slid all the way back, and I am riding on the nose of the saddle.

Help!
 

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I have a KCNC but am not a big fan of the cradle design and substituted another one that has a grooved section about an inch long for the saddle rails to sit in (a standard cradle design). It only added about 7 grams to the post and holds the seat more securely (and I hope more resistant to rail damage). Would likely help with your problem of the saddle moving.
 

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stevesbike said:
I have a KCNC but am not a big fan of the cradle design and substituted another one that has a grooved section about an inch long for the saddle rails to sit in (a standard cradle design). It only added about 7 grams to the post and holds the seat more securely (and I hope more resistant to rail damage). Would likely help with your problem of the saddle moving.
Could you elaborate more on what you used? Like the OP I like the KCNC seatpost but I am forever readjusting the saddle on my hardtail as it always slips (yes everything is torqued to spec etc etc).

I'd personally be very grateful for a fix.
 

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Discussion Starter · #6 ·
Yes, I too am curious about the modification above. What seatpost did you take it from? Something with a nice bed for the rails, like a thomson clamp's lower half wouldn't fit with the KCNC design methinks.

nino said:
May i add one more 30,9 seatpost?

Token Carbon 30,9/350: 140g (verified)
Ah nino, always a step ahead! I will have to look into this other option. From your blog, I see that the clamp design is the same as KCNC. What can be done to make it more robust and reliable?

My saddle has usual ti rails. Maybe carbon rails would be more grippy, hehe.
 

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~ScaryFast~ said:
Yes, I too am curious about the modification above. What seatpost did you take it from? Something with a nice bed for the rails, like a thomson clamp's lower half wouldn't fit with the KCNC design methinks.

Ah nino, always a step ahead! I will have to look into this other option. From your blog, I see that the clamp design is the same as KCNC. What can be done to make it more robust and reliable?

My saddle has usual ti rails. Maybe carbon rails would be more grippy, hehe.
I have these kind of seatposts on ALL my bikes for the last 4-5 years and none is slipping. I don't know what the problem is but maybe just as mentioned above you guys should try to put some grease on the bolts thread.Maybe this allows for more torque which makes for a thight fit? Maybe the friction caused in the thread is too high so the torque wrench stops before the "real" measurement is reached? i don't know. But as mentioned i have these clamps on all my bikes, also on my Winterbikes where i used regular Ti-railed SLRs as well.
 

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G-Live said:
I'd stay with the Thomson and a shim. Not the true WW solution but a cheap and easy one.

G
How well does shimming work? I have to go from 27.2 to 30.9 as well and my Thomson Masterpiece is nearly brand new. I was planning on buying a new one and trying to sell the current one ... but might prefer to just get a shim .... if it works w/out hassle.

It would have to make adjusting post height a bit of a hassle ... but otherwise?
 

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slcpunk said:
How well does shimming work? I have to go from 27.2 to 30.9 as well and my Thomson Masterpiece is nearly brand new. I was planning on buying a new one and trying to sell the current one ... but might prefer to just get a shim .... if it works w/out hassle.

It would have to make adjusting post height a bit of a hassle ... but otherwise?
I've used a metal shim 27.2 to 30.9 that was seamless to use. Grease shim and post. Shim with relief cut will tend to expand in seattube and stay put when you move post.
 

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BadHabit said:
I've used a metal shim 27.2 to 30.9 that was seamless to use. Grease shim and post. Shim with relief cut will tend to expand in seattube and stay put when you move post.
cool. $7 is hard to argue with...although my "lightweight" (surely not by most on this forum's standards) Masterpiece does seem wasted...with such a hack.
 

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slcpunk said:
cool. $7 is hard to argue with...although my "lightweight" (surely not by most on this forum's standards) Masterpiece does seem wasted...with such a hack.
I read here recently that smaller-diameter carbon posts are more resilient/compliant than larger--makes sense--maybe carries over a small bit into alloy.
 

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I must do this also... With my new Tomac...
Sux in a few ways
First gotta Ditch my 2 brand new carbon collars..31.8
And if shim doesn't work I,m down another masterpiece.

Have current one at 148 grams modified without cutting it.

So 140$ down in collars ... Just hope shim works... And going to try to get rid of collars...
But eBay clueless...
 
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