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Discussion Starter · #1 ·
There is a large (4mm) gap between the bottom of my QR seatpost collar and the top of the main carbon part of the frame. The collar is pressed down all the way with the machined lip resting on top of the carbon insert. The collar and frame have matching curves and look like they should be nearly touching. It's like the carbon insert is too tall or not fully inserted into the frame. How tall is the gap on your Mojo SL with bolt or QR collar?


 

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After further review...
I would just sand top of seat insert with a flat file, (stick a rag down the tube first) then proceed a little at a time. I would not cut it even with a hacksaw guide blade and a carbon blade. (Just because it is such a small amount and better too high than too low.
Btw, be sure and use a little bit of the included carbon tacx grease (NOT regular grease) on the seattube/seatpost interface. (I did not see evidense of any in the tube in the pic.) Happy Holidays.
 

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Discussion Starter · #7 ·
Thanks for the pic to give me some reference. Even your's would look better with less gap but my gap is over 1mm greater than your's. It's not that big a deal I guess but with this pricy a frame greater "fit and finish" would be appreciated. I'm waiting to hear back from an email I sent to Ibis.

P.S. I think they should go back to the drawing board on their QR collar. It's too heavy (61g vs my Yeti's 37g) and there's no need for the 8mm of aluminum sticking up above the seat tube . It looks like they had a sculptor design it, rather than an engineer. They could increase the clamping area and make the gap disappear.
 

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Unpredictable
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The seatpost sleeve (insert) is sitting a little high, but is it loose? Don't use a dremmel or file as you may make the clamp less effective. The slit which allows the clamp to compress the seatpost in the sleeve is fairly short and making it shorter may make it less effective.
 

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www.derbyrims.com
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Without pulling mine apart to see, it looks like in your pictures that you could file the forward edge of the post insert down that amount and not loose any strength, and maybe get better post grip with less clamp leverage. Better check with Ibis first.

Mine is flush, no gap ('06 Mojo, not SL).
 

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you're right

That one is a bit proud as they say. I had one like that on a trade show bike a while ago and carefully cut a couple of mm off the top of the seat tube insert with a hacksaw. Then it was a near perfect fit.

Obviously, you would want to have a steady hand and make a guide for yourself out of tape and then clean up the edge with sand paper.

We also have a 14 gram binder with Ti bolt that looks good one the frames, it comes stock on the SL. Let us know if you need one.

Hans
 

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Discussion Starter · #15 ·
I may get the bolt-on collar for the weight drop but I've always used a QR so I ordered my SL with one. Please consider redesigning the QR to be less pretty but more practical.
As always, thank you for keeping an eye on the forums and being so hands-on with your customers Hans. I really am stoked with the bike.
 

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Mines exactly the same distance as the OPs, doesnt bother me enough to take a saw to my frame tho lol...

One question, why not use regular greasefor the seatpost, i am doing so. I figured the carbon specific ones just contain a slight abrasive to enhance grip and reduce clamping force, does regular grease harm carbon?
 

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Discussion Starter · #18 ·
Some kinds do but most likely the one you're using doesn't. Grease will increase the chance of the post slipping and require more clamping force. You'd be better off with no grease. Your bike came with a little packet of the carbon grease right? Seems best to use it and go easy on the torque.
 

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Discussion Starter · #19 ·
Hey Hans, can I just use the finest tooth hacksaw blade at the hardware store or should I try to borrow a carbon specific blade from a bike shop. I saw one of these at a shop I worked at years ago but I don't know if any shops around me have it.
 

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hanssc said:
If you have an alloy insert / carbon post combo the grease seems to enhance galvanic corrosion / stuck seat post syndrome. The grease does not harm the carbon though, it's just more conductive than the LPS1 we use.
H
Ok im on the SL so no issues. I did get the FSA grease with the frame but due to the muddy winter here in the uk and deep cleaning after every ride got thru it all. I use a brand called rock n roll, it doesnt wash away like the fsa and no slipping issues with a thomson post.

Thanks for the heads up
 
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