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the bolt or quick-release lever which clamps the post in the frame, especially where this acts on two brazed lugs rather than a separate clamp-on collar. Overtightening can bend or break the frame lugs or strip the threads in a separate collar. Metal seatposts should be very well greased, with the slot in the bicycle's seat tube also filled with a smear of grease. This helps to prevent water from running down the seat tube.
961:
355:. This can be used to quickly lower the saddle and position it out of the way to allow for better body positioning and maneuverability on technical sections. The same lever or switch can then be used to return the saddle to its normal position for better pedaling efficiency. Most dropper seatposts use a hydraulically damped air or coil spring with cable, hydraulic, or electronic actuation.
41:
255:
17:
201:
Conversely, an "in line" post may be required if the seat tube angle is too slack. Some saddles, notably Brooks leather saddles, have relatively short rails, allowing less adjustment of setback, and changing the seatpost or inserting a saddle adjuster may be the only way to achieve the correct position.
411:
Seatposts should be periodically removed from the frame, cleaned, greased and refitted to prevent the seatpost seizing in the frame. This is particularly important with bikes which do not have mudguards (fenders) that are regularly ridden in wet conditions. Care should be taken not to overtighten
214:
This type, usually found on older bikes, less expensive bikes, or kids bikes, consists of a tube which may decrease in diameter for the last inch or so (2.54 cm) and a separate clamping mechanism at the top. One bolt tightens the clamp to the rest of the seatpost and to the saddle rails at the
307:
bikes. They have a concave semicircle of ridges at their top that matches the convex semicircle of ridges on the bottom of a pivotal saddle. The two semicircles are held together with a bolt to attach the saddle to the seatpost. Pivotal seatposts are currently expanding rapidly in popularity with
262:
As alternatives to the integrated seatpost mentioned above, some seatposts merely have an aerodynamic shape that either matches the shape of the aero seat tube or is only not round above a certain point. In the case of aero seat tubes, there are a variety of clamping mechanisms for such seatposts
245:
frames are made from one piece of molded carbon fiber with an integrated seatpost that is cut to length depending upon the rider, also known as a seat mast. The advantage is that it is lighter, can be molded into an aerodynamic shape, and removes the need to clamp an irregular tube shape. The
200:
Offset or "layback" can range from 0 mm to 45 mm. A seatpost with offset is necessary when the seat tube angle of the frame is too steep to give the desired saddle setback (the horizontal distance between a plumb line hung from the nose of the saddle and the bottom bracket spindle).
122:
can be used). The seatpost is held in place by squeezing the top of the seat tube with a tightening ring (temporarily reducing its diameter; a vertical slit cut into the tube allows this to happen without crumpling) until the tube firmly hugs the post where it leaves the frame. A hole for a
127:(also known as a "binder bolt") may be built into the frame for this purpose, or a "seatpost clamp" may be purchased separately (but must be sized to closely fit the diameter of the seat tube). Whether integrated or separate, the seatpost bolt can have a simple nut, can be an
415:
There is some controversy about whether to grease carbon seatposts or not. There does not yet appear to be a consensus. There are now specialty products, referred to as "carbon prep" or "carbon paste", specifically for the interface between carbon and most other materials.
149:
of the bicycle frame. They come in various diameters, lengths and offsets. Offset is the distance between the centerline of the seatpost tube, and the centerline of the clamp area. Shims are often available to adapt a too-small seatpost to a too-large seat tube.
131:, or can include a quick-release mechanism, with a handle that releases the clamp without tools. A quick-release allows easy height adjustment of the seat, though increases the risk of seat theft unless it is also used to detach the seat when parking.
326:
Madones, provide saddle height adjustment with a seatmast and cap arrangement. The seatmast is extension of the seat tube above the top tube, and the cap slides into it, clamps in place, and attaches to the saddle.
163:
bikes commonly use 25.4 mm seatposts. In some modern bikes with thicker alloy or carbon tubing, larger diameters such as 30.9 mm are used. Tapering seatposts often have a diameter of 22.2 mm
158:
Seatpost diameters generally range from 22 mm to 35 mm in 0.2 mm increments. The most common size is 27.2 mm (1.07 in) for most bikes, especially for the higher-quality models.
80:. The amount that it extends out of the frame can usually be adjusted, and there is usually a mark that indicates the minimum insertion (or maximum extension). Seatposts can be made of
223:
They can be divided into two types; ones which can adjust the saddle angle continuously, and ones in which the saddle angle can only be adjusted to a certain number of positions.
263:
that include pinch bolts and wedges. Aero seatposts are typically proprietary designs for a specific frame model and thus cannot be mounted on bikes of other manufacturers.
539:
saddle pin n. (a) any of various pins which fit into a saddle (in various senses) or resemble a saddle in shape (rare); (b) Motorcycling and
Cycling = saddle pillar n.
760:
246:
disadvantage of this setup is that the seatpost height is not as adjustable. There is usually 2-3 centimeters of adjustment with the clamping device.
880:
395:
33:
371:
687:
383:
180:
collected and published a list of seatpost diameters on his website, evidence of the common problem of finding compatible replacements.
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670:
111:
with which they must be compatible, while old or inexpensive seatposts slide into a separate clamp that then clamps the saddle rails.
853:
461:
436:
279:
Suspension seatposts allow the saddle to move up and down with either a telescoping or parallelogram mechanism and incorporate a
177:
803:
522:
saddle pillar n. Motorcycling and
Cycling the pin extending from a cycle saddle which fits into a socket on the cycle frame.
733:
873:
93:
295:
and mountain bikes. Suspension seatposts usually come in fewer diameters, and shims are more likely to be necessary.
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to insulate against bumps. The preload of the spring may be adjustable. These seatposts are most common on
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734:"2011 Dropper Seatposts, Mountain bikers have several new options to choose from next year"
599:
1190:
1150:
1130:
761:"Milan-San Remo: Dropper post was Matej MohoriÄŤ's secret weapon on winning Poggio descent"
280:
804:"Installation Instructions Profile Design Razor & O3 Carbon Seatposts [sic]"
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492:. International Triathlon Union (ITU) / China Triathlon Sports Association (CTSA)
258:
An aero seatpost in an aero seat tube held with two pinch bolts on an Orbea Ordu.
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To attach it to the bicycle's main frame, the seatpost is inserted into the
571:
254:
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The size of the seatpost is dependent upon the internal dimensions of the
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can be remotely adjusted while riding using a lever or switch on the
118:, which must be of a very slightly larger diameter (or a cylindrical
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270:
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81:
39:
31:
15:
712:
858:
827:"Technical Q&A with Lennard Zinn - ... carbon questions ..."
862:
36:
A microadjust seatpost (black) of a Trek Fuel 80 mountain bike.
304:
160:
45:
361:
used a dropper seatpost on his road bike to help him win the
779:"Technical Q&A with Lennard Zinn - More greased carbon"
192:
seatposts tend to be longer than road bicycle seatposts.
401:
Control lever for a dropper post mounted on handlebars.
487:"2010 WEIHAI ITU LONG DISTANCE TRIATHLON WORLD SERIES"
1108:
1072:
1011:
968:
896:
688:"Tech Report, with Lennard Zinn – The new Madone"
665:(4th ed.). Park Tool. pp. Chapter 15.
188:Lengths range from 75 mm to 430 mm.
874:
661:Jones, C. Calvin (2019). Garceau, Dan (ed.).
8:
639:"Compact frame geometry and aero seatposts"
44:A seatpost with a significant setback on a
881:
867:
859:
600:"Sheldon Brown's Bicycle Glossary Sa - So"
586:"Sheldon Brown's Bicycle Glossary Ba - Bn"
501:One(1) bike number, to be attached to the
275:Suspension seatpost (parallelogram type).
20:A "plain" seatpost (silver) connects the
615:"Sheldon Brown's Seatpost Size Database"
104:Seatposts generally clamp directly onto
72:is a tube that extends upwards from the
431:
429:
425:
367:
96:, or aluminum wrapped in carbon fiber.
656:
654:
7:
572:"Sheldon Brown's Bicycle Glossary P"
287:, or compressed air and possibly a
313:Bicycle saddle § Saddle_clamp
228:Bicycle saddle § Saddle_clamp
14:
335:Dropper seatposts (also known as
959:
394:
382:
370:
303:Pivotal seatposts are common on
713:"Modeling seatmasts in BikeCAD"
663:Big Blue Book of Bicycle Repair
759:Hood, Andrew (19 March 2022).
552:"Felt 6061 T6 Carbon Seatpost"
1:
686:Lennard Zinn (Jun 5, 2007).
136:Bicycle saddle § Rails
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310:
225:
133:
957:
535:Oxford English Dictionary
518:Oxford English Dictionary
850:seatpost sizing database
537:(2nd ed.). 1989.
520:(2nd ed.). 1989.
377:Extended dropper post.
276:
259:
174: in) at the top.
49:
37:
29:
389:Lowered dropper post.
311:Further information:
274:
257:
226:Further information:
134:Further information:
43:
35:
19:
1003:Quick release skewer
619:www.sheldonbrown.com
466:"Glossary: Seat Pin"
441:"Glossary: Seatpost"
322:Some bikes, such as
363:2022 Milan–San Remo
277:
260:
50:
38:
30:
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196:Offset or layback
100:Attachment points
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318:Seatmast and cap
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219:Micro-adjustable
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890:Bicycle parts
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854:Sheldon Brown
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785:on 2006-10-17
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365:one-day race.
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359:Matej MohoriÄŤ
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337:dropper posts
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190:Mountain bike
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66:saddle pillar
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1085:Bowden cable
988:Spoke nipple
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821:
810:. Retrieved
798:
787:. Retrieved
783:the original
773:
764:
754:
743:. Retrieved
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728:
717:. Retrieved
715:. BikeCAD.ca
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695:. Retrieved
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494:. Retrieved
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470:. Retrieved
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445:. Retrieved
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349:gravel bikes
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94:carbon fiber
69:
65:
61:
57:
53:
51:
1181:Skirt guard
1126:Bottle cage
1109:Peripherals
1090:Cable guide
1040:Master link
503:saddle pole
407:Maintenance
215:same time.
1176:Reflectors
1171:Spoke card
1050:Derailleur
1013:Drivetrain
993:Valve stem
951:Suspension
906:Handlebars
832:2008-08-21
830:Retrieved
812:2008-01-21
789:2007-01-18
745:2013-01-25
719:2014-04-02
697:2010-07-11
644:2008-08-21
624:2023-05-08
557:2009-01-26
496:2010-07-25
472:2010-07-25
447:2009-08-02
420:References
267:Suspension
233:Integrated
129:Allen bolt
125:pinch bolt
70:saddle pin
62:saddlepole
52:A bicycle
1166:Saddlebag
1156:Mudguards
1141:Kickstand
1059:Gear case
1054:Hub gears
916:Head tube
739:Bicycling
711:BikeCAD.
353:handlebar
285:elastomer
154:Diameters
147:seat tube
116:seat tube
1206:Category
1161:Panniers
1146:Lighting
1064:Sprocket
1026:Crankset
946:Fork end
931:Seatpost
765:VeloNewd
692:VeloNews
345:mountain
341:droppers
90:titanium
86:aluminum
54:seatpost
1131:Fairing
1100:Ferrule
1080:Shifter
1073:Cabling
998:Dustcap
921:Headset
331:Dropper
299:Pivotal
169:⁄
76:to the
58:seatpin
24:to the
1186:Fender
1116:Basket
1045:Cogset
970:Wheels
936:Saddle
669:
293:hybrid
289:damper
281:spring
184:Length
106:saddle
78:saddle
28:(red).
22:saddle
1095:Brake
1031:Chain
1021:Pedal
983:Spoke
898:Frame
807:(PDF)
490:(PDF)
343:) on
283:, an
210:Plain
205:Types
141:Sizes
109:rails
82:steel
68:, or
48:bike.
26:frame
1121:Bell
1035:Belt
978:Tire
926:Fork
911:Stem
667:ISBN
347:and
324:Trek
250:Aero
241:and
239:road
120:shim
852:by
339:or
305:BMX
161:BMX
46:BMX
1208::
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171:8
167:7
164:(
Text is available under the Creative Commons Attribution-ShareAlike License. Additional terms may apply.
