Your take on Mcfk seatpost & seat-clamp?

Discuss light weight issues concerning road bikes & parts.
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by sugarkane

Yea your right it's not magic. If you need more than 4.5nm on the seat clamp something is defiantly too small

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by DMF

Here's something. Campag shifters on 3T carbon bars, no freaking amount of force would keep them clamps from slipping with very little hand pressure on the bars. Never had that problem with Shimano shifters on the same bars. The clamping area of the bars are btw not smooth but rather rough for extra grip.

Tried cleaning with alcohol and tried mounting several times with ridiculous amounts of force on the clamp bolt.

Googled it, known issue with Campag/3T Carbon combo, use carbon assembly paste. Said and done, they stay very secure with average force on the clamping bolt. This stuff works.

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by NiFTY

Just spray some extra layers of clear coat around the clamp zone. Preferably matt/satin (grippier). After having some slip with numerous posts i did this and have never had another slip with standard torque values. I use carbon paste too.
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by Limbo

I sent an email to the bike manufacturer : and it was confirmed 27.2mm.
I also sent an email to Mcfk directly for confirmation : and it is also confirmed 27.2m, and are compatible with my bike brand.
With two assurance on-hand: I went on to measure both the seatpost and frame seat diameter with my caliper and readings came out accurate too.

I went on to consult my trusty LBS for possible advise, and was told to use carbon paste.
Used the paste on the frame, and a week passed without any slippage in last two 3 hours++ rides.

Many thanks for the contribution and providing possible scenarios.
I will continue to monitor it for another week to a month, just in case.

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by DMF

Did you use an accurate digital caliper that shows 2 decimals and took measurements from several different angles at several different depths to rule out any potential oval tubes. To be fair it is extremely difficult to measure a seat tube inner diameter within a consistent 0.05mm (or preferably less) margin of error, as it may also vary along the length of the tube. That btw goes for both seat tube and seat post, albeit the post is a lot easier to measure, but would still require atlest 10-15 different measuring points to be considered accurate...

I've seen 0,15mm variations within the same aluminium seat post (not the same model, the actual same post!)

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