Darby
sage
Reged: 08/03/06
Posts: 420
Loc: Orange County California
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I am having a bit of a love hate relationship with my seat post. For the past of couple of years it has worked flawlessly, until I realized it was too low and raised it one inch. Now it won't stay put. I start out on a ride with it adjusted where I want it, but by the 10 mile mark it has drop one inch. I have taken it apart and cleaned it to make sure that there is no grease or oil.
I had heard that there is some sort of gritty chemical that I can coat the seat post with so that it doesn't slip--anyone familiar with this chemical?
By the way, my seat post is a Thompson Elite which is about as good as seat post can get or so I hear.
Bruce
Edited by Darby (06/15/08 02:12 AM)
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CalfeeJames
new member
Reged: 11/12/07
Posts: 7
Loc: Santa Cruz, CA
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Yes, it's called Fiber Grip and it's made by Finish Line. You can also try ordering a new seat collar from us as yours may have become stretched or warped. They cost $18 for the somewhat unusual 33mm size. Email repairs@calfeedesign.com
CalfeeJames, repairs guru, Calfeedesign
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Darby
sage
Reged: 08/03/06
Posts: 420
Loc: Orange County California
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Quote:
CalfeeJames wrote:
Yes, it's called Fiber Grip and it's made by Finish Line. You can also try ordering a new seat collar from us as yours may have become stretched or warped. They cost $18 for the somewhat unusual 33mm size. Email repairs@calfeedesign.com
CalfeeJames, repairs guru, Calfeedesign
James,
Thanks for the recommendation. I have already ordered the Finish Line product and will most likely change the seat collar as well.
Bruce
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Umlungu
contributor
Reged: 03/04/05
Posts: 183
Loc: Plano, TX
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Sounds Like FiberGrip is the way to go. Especially if the recommendation comes from James.
(BTW - Welcome James! - It's great to see you here on the boards)
I had this same issue in the past with an Alpha Q carbon post. Someone told me to give toothpaste a try which I did and it worked. I ended up switching to the Thompson Masterpiece and never had slippage issues after that. If you want a stopgap measure till your FiberGrip arrives you might try the Crest/Colgate/Aquafresh school of bike repair.
- Michael Whitley
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Darby
sage
Reged: 08/03/06
Posts: 420
Loc: Orange County California
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Quote:
Umlungu wrote:
Sounds Like FiberGrip is the way to go. Especially if the recommendation comes from James.
(BTW - Welcome James! - It's great to see you here on the boards)
I had this same issue in the past with an Alpha Q carbon post. Someone told me to give toothpaste a try which I did and it worked. I ended up switching to the Thompson Masterpiece and never had slippage issues after that. If you want a stopgap measure till your FiberGrip arrives you might try the Crest/Colgate/Aquafresh school of bike repair.
- Michael Whitley
Hi Michael,
I didn't know about the tooth past or I would have tried it. However, I did order the FiberGrip which should be here in a day or two. James also recommended changing the collar which I may do but will probably try the FiberGrip first.
Bruce
Edited by Darby (06/16/08 09:01 PM)
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Umlungu
contributor
Reged: 03/04/05
Posts: 183
Loc: Plano, TX
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Very good Bruce. Let me know how that stuff works.
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TandemGeek
new member
Reged: 05/25/08
Posts: 5
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I haven't used the Finish Line Fiber Grip, but have experience with FSA's carbon Installation Compound and Tacx Dynamic Paste. They all appear to be similar products that use micro polymer spheres suspended in a gel and are a must have for the home shop, especially if you're using carbon seat posts, handlebars, or stoker stems. Also, for Calfee tandem owners, these pastes work quite well on the eccentrics.
FSA's packaging / pricing is a bit obscene -- too much for too little -- but uses what seem to be slightly larger sphere's than Tacx making it bite better than the Tacx paste. However, the Tacx stuff can be found in a small tub that you can find for as little as $10. While the micro polymer spheres are a bit smaller what you'll find in FSA's paste, it works just as well. Again, Finish Line's paste looks similar and the pricing seem reasonable too.
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Darby
sage
Reged: 08/03/06
Posts: 420
Loc: Orange County California
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I put FiberGrip on my seatpost about a week ago and so far so it hasn't slipped at all.
FiberGrip is transparent jell with a look and feel that reminds me of Vasoline with sand in it. At any rate, it works.
I highly recommend it.
Bruce
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Umlungu
contributor
Reged: 03/04/05
Posts: 183
Loc: Plano, TX
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Great to hear! Thanks for the follow up.
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Don_Ventura
new member
Reged: 06/09/08
Posts: 3
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Quote:
Darby wrote:
I am having a bit of a love hate relationship with my seat post. For the past of couple of years it has worked flawlessly, until I realized it was too low and raised it one inch. Now it won't stay put. I start out on a ride with it adjusted where I want it, but by the 10 mile mark it has drop one inch. I have taken it apart and cleaned it to make sure that there is no grease or oil.
I had heard that there is some sort of gritty chemical that I can coat the seat post with so that it doesn't slip--anyone familiar with this chemical?
By the way, my seat post is a Thompson Elite which is about as good as seat post can get or so I hear.
Bruce
I had the exact same problem with a 27.2mm Thomson Elite seatpost slipping. A 27.2 Campy post worked perfectly, no slippage. I measured the diameter of the Thompson post with a dial caliper at several points, and found the seatpost to be undersized. According to the Thompson engineering drawing, the 27.2 seatpost should have an outside diameter of 27.15mm +.00/-.03mm. That means the minimum diameter should be 27.12mm, and my measured diameter was considerably smaller than that. I telephoned Thompson and they agreed to exchange my seatpost for one that was within spec.
This is a fairly common problem with Thompson seatposts if you can believe the various internet reports, and if this is your problem, I don't believe you can remedy the slippage until a correctly sized seatpost is used.
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Darby
sage
Reged: 08/03/06
Posts: 420
Loc: Orange County California
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Quote:
Don_Ventura wrote:
Quote:
Darby wrote:
I am having a bit of a love hate relationship with my seat post. For the past of couple of years it has worked flawlessly, until I realized it was too low and raised it one inch. Now it won't stay put. I start out on a ride with it adjusted where I want it, but by the 10 mile mark it has drop one inch. I have taken it apart and cleaned it to make sure that there is no grease or oil.
I had heard that there is some sort of gritty chemical that I can coat the seat post with so that it doesn't slip--anyone familiar with this chemical?
By the way, my seat post is a Thompson Elite which is about as good as seat post can get or so I hear.
Bruce
I had the exact same problem with a 27.2mm Thomson Elite seatpost slipping. A 27.2 Campy post worked perfectly, no slippage. I measured the diameter of the Thompson post with a dial caliper at several points, and found the seatpost to be undersized. According to the Thompson engineering drawing, the 27.2 seatpost should have an outside diameter of 27.15mm +.00/-.03mm. That means the minimum diameter should be 27.12mm, and my measured diameter was considerably smaller than that. I telephoned Thompson and they agreed to exchange my seatpost for one that was within spec.
This is a fairly common problem with Thompson seatposts if you can believe the various internet reports, and if this is your problem, I don't believe you can remedy the slippage until a correctly sized seatpost is used.
Wow, I thought Thompson was one of the most respected seatpost manufacturers. I will monitor it and see if Thompson will help out in this department.
I had thought about buying a Campy seatpost but was concerend about two things, the carbon fiber on the seatpost would scratch as I adjusted it. The other was that the one bolt adjustment wouldn't be percise enough.
Thanks for letting me know.
Bruce
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skuke
captain
Reged: 12/22/03
Posts: 321
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Quote:
Don_Ventura wrote:
...I measured the diameter of the Thompson post with a dial caliper at several points...
...According to the Thompson engineering drawing, the 27.2 seatpost should have an outside diameter of 27.15mm +.00/-.03mm.
Not to imply that your seat post isn't undersized, but dimensions with tolerances that tight should be measured with a micrometer, not dial calipers.
--------------------
Skuke
95 Carbonframes Tetra Pro
92 Bridgestone MB-1
90 Moser 51.151
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cccyclist
journeyman
Reged: 09/27/05
Posts: 80
Loc: Central California
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I think Thompson has gone down hill in the last few years. I have always used their seat posts, but tried their X2 stem with carbon bars and couldn't get it to clamp down enough. The end cap would bottom out on the stem before there was enough force to keep the bars from rotating. It was only marginally better with aluminum bars. Eventually They began slipping also, so I scrapped it.
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Don_Ventura
new member
Reged: 06/09/08
Posts: 3
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Quote:
skuke wrote:
Quote:
Don_Ventura wrote:
...I measured the diameter of the Thompson post with a dial caliper at several points...
...According to the Thompson engineering drawing, the 27.2 seatpost should have an outside diameter of 27.15mm +.00/-.03mm.
Not to imply that your seat post isn't undersized, but dimensions with tolerances that tight should be measured with a micrometer, not dial calipers.
The dial calipers I used have a resolution of 0.01mm. Thompson confirmed my measurement when I returned the seatpost for warranty replacement. The replacement seatpost measured within tolerance using the same Mitutoyo calipers. Apparently they were sufficiently accurate for this purpose.
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Darby
sage
Reged: 08/03/06
Posts: 420
Loc: Orange County California
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Update on the FiberGrip.
I have put over 100 miles on my bike since using the FibeGrip and the seatpost hasn't slipped at all.
I think this is enough time to say that FiberGrip works.
Bruce
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skuke
captain
Reged: 12/22/03
Posts: 321
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Quote:
Don_Ventura wrote:
Quote:
skuke wrote:
Not to imply that your seat post isn't undersized, but dimensions with tolerances that tight should be measured with a micrometer, not dial calipers.
The dial calipers I used have a resolution of 0.01mm. Thompson confirmed my measurement when I returned the seatpost for warranty replacement. The replacement seatpost measured within tolerance using the same Mitutoyo calipers. Apparently they were sufficiently accurate for this purpose.
Again, a dimension with a tolerance of +.00/-.03mm should be measured with a micrometer rather than calipers.
Your caliper may have a resolution of .01mm but it's accuracy is .02mm. In addition, calipers are more prone to frame flex, loosening of the jaws, and operator error from over/under pressuring the jaws. Calipers jaws are more difficult to keep parallel and I've never seen one that has heat (from your hands) insulation. Dial calipers are subject to parallax error. Digital and vernier calipers don't have a parallax error.
I'm not saying your measurements is wrong. I'm saying that you can't say with reasonable certainty that it's accurate (correct). It would be like asking you to time a foot race to the nearest second with a regular wrist watch. You could time the race, but you couldn't be reasonably certain that your time is accurate to the nearest second.
--------------------
Skuke
95 Carbonframes Tetra Pro
92 Bridgestone MB-1
90 Moser 51.151
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spted
new member
Reged: 11/03/04
Posts: 11
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I've been using FSA's stuff on my seatpost. I recently ran across this alternative, too: Effetto Mariposa CarboGrip. I can't vouch for it, having not used it (yet). But the price is much more reasonable than the FSA product and Effetto makes a great torque wrench.
http://cantitoeroad.com/catalog/product_info.php?cPath=21&products_id=32
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