How Do I Find Out My Seatpost Size

Replacing your wheel dropper can be daunting if you don't know how to determine Seatpost size. A good Seatpost is the key to achieving a comfortable ride. Further, it enhances the aerodynamics and usability of your cycle. The Seatpost is ane of the most overlooked components of the bike, yet critical for efficiency and performance. Installing the incorrect size not but damages the frame of the bike only tin can also lead to back pain. How then do you lot determine the size of your Seatpost to avoid all this? We have prepared a step-by-footstep guide that volition show you how to measure your saddle postal service and then that you lot can get the full benefit out of your workout.

How to Determine Seat Post Size

Look at the Old Seatpost

It might seem obvious, but it is worth maxim, you tin decide the seat postal service size by looking at your existing or former saddle mail service. This is the simplest fashion to know the size of your dropper.

If y'all plan to change your Seatpost and don't have a clue nigh the measurement, then you need to pull out your old mail service and check. By and large, the sizes are unremarkably stamped, or laser marked near the stop of the insertion line.

Measure Your Old Seat Post Diameter

Due to old historic period and frictions, the marking tin be erased. Thus, how do y'all decide the size of your dropper? Well, this is where we get hands-on and have the measurement. You lot tin can easily measure the size of the post using a digital caliper and metric calipers to check the bore of the existing seat mail service.

First, if you lot accept an one-time saddle-post that attaches firmly, then you can mensurate its outer diameter for an accurate guess of what yous need to buy. However, if the one-time seat post is worn out and y'all are unable to make reasonable estimates from it, and then you demand to follow the next step, where nosotros will show you how to measure out the seat tube to determine the right seat post size.

Find Your Seat Tube Bore

How do y'all measure your bicycle seat mail service size if y'all don't take an existing seat mail service? Well, it is simple, read on.

A seat tube is a frame that holds the Seatpost. Put it another way; information technology is where you mount the seat postal service. When measuring the seat tube, you should pay close attention to the internal diameter of where the seat mail service will be inserted. Ensure yous don't measure the external diameter equally it does non help measure Seatpost size.

We recommend using a Vernier caliper to measure the diameter of the seat tube. Vernier caliper is extremely precise when taking either external or internal measurements. You tin can check for calipers with digital readouts, which you lot can set in metric or inch at the click of a button.

Do You Want an Internal or External Routing?

Cable routing of the Seatposts can be internal or external. Internal routing (as known as stealth) is the near common type of cabling in mountain bikes. In internal cable routing, the Seatpost is linked to the remote level at the shaft of the postal service. Contrary, in external cablevision routing, cables are routed on the outside of the tube and attached to the shaft or the head of the mail.

The routing you lot take will determine the type of postal service size that you lot will get for your bike. I advise y'all go for the seat postal service, which has the cablevision routed to the shaft as opposed to the head of the post. This makes information technology less prone to harm and looks groovy aesthetically.

Determine the Travel Needed

The next crucial gene in determining the seat post is the length of the dropper. The length of the dropper is ever measured when the post is at full extension.

Also, yous need to know how much "drib" you need. Well-nigh bikes will have an assart of 100 to 150 mm. Information technology is advisable to get as much travel as you tin can become. This means that you have the liberty to move the seat, and you can lower information technology for more comfort and fun. Ultimately, you want a seat post that will maintain your saddle in a position suitable for pedaling. Avert going for a seat postal service that leaves the seat likewise high even when fully inserted in the frame.

Determine Your Maximum Extension

To measure the size of the seat postal service correctly, you need to determine the tiptop you want to have when your seat is extended to the maximum. You practise this past measuring the seat from the neckband to the center of the seat rail. When choosing a post, you don't desire it to be too long since information technology tin can impact the efficiency and transfer of ability when pedaling.

Determine Your Minimum Insertion

How deep tin you insert your Seatpost into the frame? You tin can determine the size by measuring from the acme of the saddle collar down to where you feel in that location is nothing that can become further. It is essential to know the minimum insertion because it helps you to avert focusing on extension numbers that tin can mislead you lot and make it hard to adjust your postal service to lower points.

Determine the Overall Length

The overall length of the dropper is crucial when determining the size. Seatpost vary in length, and if you are looking for ane, yous should brand sure that the length is sufficient for your needs. A brusque post can be uncomfortable and ergonomically unfit. Most Seatpost lengths range between 75 mm to 400mm.

Brusk Seatpost tend to exist lightweight but less adjustable, while longer Seatpost tend to be more flexible. From observation, most mountain bikes have longer Seatpost, which makes them easy to adjust for uphill and downhill terrains, making them safety and offering you protection against injury.

Use Seat Mail Sizing Rod

How else can you mensurate Seatpost diameter? We have additional ways that you can determine the size of your seat post. I of those includes the use of seat sizing rods. To measure, you lot place the rod within the seat tube and match the diameter. The rods are designed to have an increasing diameter from one end to the other. Therefore, the correct reading, which matches, is the one above the terminate of the seat tube.

Bank check Manufactures Website

In this age of the internet, you tin can determine the size of your post by checking the manufactures website or through Google. Nigh manufacturers will put a catalog of the saddle size for their model, and the seat-tubes they can fit. So, if you are planning to replace your post, I suggest you visit the manufacturer's website for details. You should also read below for more information on post sizes and their fit.

Additional Measuring Hacks

In instance you don't have a Vernier caliper, you tin can employ an adjustable wrench to measure out.
Measuring is better than guessing. However, if yous don't take the tools to measure out, you tin use the nautical chart developed by Sheldon Chocolate-brown (or the nautical chart provided in the FAQ section)to compare and determine the size.

FAQ

What Size Seatpost Do I Need?

The size of the dropper depends on your needs. Yet, y'all should exist aware that the size of the mail service can touch the efficiency and the comfort of your wheel. For instance, an oversize post makes a wheel to be stiff though it enhances power transfer when pedaling. On the other manus, a narrow mail is more than comfortable on a rough surface.

Lastly, you lot need a Seatpost whose diameter can fit with the diameter of the seat tube for a perfect snug fit. Going past the industry standards, the most common size that fits nigh bikes' frame is 27.2 in diameter (which is standard), and thirty.9 or 31.66mm

Will A 31.6 Seat Postal service Fit A 30.9 Frame?

No. Yous demand a larger frame. Trying to fit a large seat mail in a small frame tin lead to damage. As a full general rule, if the seat postal service is bigger than the frame's tube, then information technology cannot fit. While at that place are some instances when manufacturers' sizes differ, it is not advisable to fit a larger post on a smaller frame.

However, on the flip side, a small Seatpost can fit in the big tube, simply yous must add together shims to fit. Therefore, you need to follow carefully the steps we have provided in this article, so yous don't brand the fault of buying a Seatpost that does not fit in your frame.

Standard Bike Seatpost Clamp Size Nautical chart

mm
21.15	25	26	27	28	xxx	31
22	25.four	26.2	27.two	28.half dozen	30.2	31. ii
22.two	25.five	26.four	27.4	28.8	30.iv	31.4
23.four	25.8	26.5	27.7	29	30.eight	31.5
23.8		26.6	27.8	29.two	30.ix	31.six
24		26.viii		29.4		31.8
				29.half dozen		32
				29.8		34.9

I recommend you lot have this chart as your checklist before buying a Seatpost. The beginning row shows the standard size of the seat tube and the different sizes that tin fit. For case, the 25 in the 2nd column tin can fit sizes 25.4, 25.5, and 25.eight.

Tin a Wrong Size Cause the Seatpost to Get Stuck?

Yep. Your Seatpost can get stuck either because of improper installation or the wrong size. Getting the right size eliminates the need to force in the post. An oversize dropper volition necessitate y'all to force information technology down, thus causing a bulge in the seat tube, while a sparse dropper will necessitate y'all to overtighten its bolts, hence causing a deformation: This is what leads to post getting stuck.

Last Verdict

A Seatpost that fits well in the bike is vital for a comfortable ride. With a good mail service, you tin can reduce loftier-frequency road vibration, rest weight, and increase the aerodynamics of the bike.

To choose the right Seatpost, you need to measure out the bore of the frame accurately. Having the correct size will give you the freedom to conquer varying terrain and have fun while at it. On the other side, getting the right measurement volition save you the cost y'all would incur in purchasing a dropper that does non fit or ane that amercement your frame.

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