Rail - Dropper post

p3eps

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Longer than...?
Mine has a 170 in a Large. How long do you want to go?
 

p3eps

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The 9.9 Large comes with 170 as standard. Not sure why another Large model would only come with 130?

2F2DEBC5-54B2-4B9E-B8B1-6A814B0815B0.png
 

Doomanic

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That's the "Dentist Spec" Rail, us mere mortals have to make do with 130mm on all sizes.
Rail 7:
1581407545845.png
 
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p3eps

E*POWAH Elite World Champion
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Dec 14, 2019
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That's the "Dentist Spec" Rail, us mere mortals have to make do with 130mm on all sizes.
Rail 7:
View attachment 25812
Weird! I get that they’d not put an AXS dropper on lower specs, but I thought they’d have done the same size?
I had about 2cm of the post out when fully dropped, so I see why you’d want to change from 130.
 

Doomanic

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I’d like to get a 150 for mine, I think 170 might be pushing it a bit. I’ll have to measure how much post is sticking out from the seat tube.
 

zaykay

Member
Dec 3, 2019
93
79
Finland
I swapped the short stock dropper to 180mm long One Up v2. What I have measured I could actually use even the longest 210mm model. There is enough insertion depth on large size frame for it. Might upgrade to that later.
 

WilkyWay

Active member
Dec 26, 2019
120
102
Durham UK
I swapped the short stock dropper to 180mm long One Up v2. What I have measured I could actually use even the longest 210mm model. There is enough insertion depth on large size frame for it. Might upgrade to that later.
Very useful information. My Large Rail 7 has the 130mm one. Set it to the right height for climbing and it’s not far enough out the way when it’s dropped, nearly been bucked a couple of times because of it. I was going to change to a 170mm ish post but I thought they may have fitted a short one because a long one wouldn’t fit all the way in. Ideally I’d want it inserted all the way into the collar.
 

Hannibal

New Member
Jan 24, 2020
16
7
Essex
In my short experience so far on my rail 7..... I manually lowered my seat on my 7 as I felt 130 was a bit silly as the nine has 170.... but when your steep enough to drop the post that much you end up with the wheel up your arse anyway so I’m not sure it’s worth getting a bigger drop. That was my conclusion on root canal at Aston hill anyway.
 

Philly G

Well-known member
Jun 29, 2020
692
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New Zealand
FYI I have just put a none dropper seat post into my 7 in Large. the seat tube will allow for around 280mm of penetration, for anyone interested.
Sounds like a Bike Yoke Divine 185mm might just fit? Total insertion length to bottom of actuator is 289mm, but you can rotate the actuator to help it fit. Tight, but OK I think?
 

Stanpipe

Active member
Jun 12, 2020
81
80
Isle of Wight - UK
DBA030D4-2E59-4EC4-AFEC-AD1F2357410C.jpeg

This gives me 915mm from top of pedal at 6 o’clock to top of saddle. This is what fits my body. It’s not the Min insertion you need (we know that fits), it’s how much post you need in the frame for your legs. I’m 33” inside leg. I’d measure what you run at mo (at full extension) and then measure what you need from pedal to top of saddle.
 

Stanpipe

Active member
Jun 12, 2020
81
80
Isle of Wight - UK
Just FYI I run 305mm from top of seat collar to top of saddle. That still leaves the 40mm of lower post above the collar. I could prob only lower another 4-5mm before it hits the kink in seat tube. Hope this helps.
 

Philly G

Well-known member
Jun 29, 2020
692
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New Zealand
Just FYI I run 305mm from top of seat collar to top of saddle. That still leaves the 40mm of lower post above the collar. I could prob only lower another 4-5mm before it hits the kink in seat tube. Hope this helps.
Thank you for all the info and photos! This is exactly the information I need. ?
 

Branny21

New Member
May 22, 2020
15
8
california
i have a 9.7 size large and fit a One up 210 dropper. Where i have it i could lower it about another 10mm. Its awesome. so the lowest i could put it is with the seat collar of the dropper about 10mm above the frame
 

Philly G

Well-known member
Jun 29, 2020
692
517
New Zealand
i have a 9.7 size large and fit a One up 210 dropper. Where i have it i could lower it about another 10mm. Its awesome. so the lowest i could put it is with the seat collar of the dropper about 10mm above the frame
That's great! The 210 oneup has a max insertion of 297mm vs 289mm for the 185 bike yoke, so I'm certain I can run the Bike Yoke fully inserted. The actuator can be rotated as well to gain extra clearance. Pulled the trigger on the Bike Yoke yesterday, so will post pics of how I get on!
 

Philly G

Well-known member
Jun 29, 2020
692
517
New Zealand
Bike Yoke 185mm fits easily
20200723_112338.jpg

into large frame, fully inserted. Didn't need to rotate the actuator to make it fit. I do get some tyre buzz though, just on my hip pack. It's my first 29er though, so could be I'm just getting used to the bigger wheels
20200723_112244.jpg
 

BiGJZ74

E*POWAH Master
Subscriber
Mar 17, 2021
573
444
American Canyon, CA
I’ve got the 210mm One-Up dropper in a Large Rail 9. 33” inside leg and post just fitted to where I needed it.
Can the 210 be inserted fully down to the collar? I'm currently running a oneup 180 but at my preferred climbing height, at full drop its a bit higher than I prefer....if its at the right drop height.....extended it's too low. I had the same issue on my Orbea rallon and the 210 was the perfect fit
 

dixie600mhz

Active member
Oct 13, 2020
174
159
Austin, Texas
Just in case it helps anyone, I'm 5' 10' with 32 inseam and the 170mm bontrager dropper was just right for me with the stock seat when fully extended. I swapped seats to ergon coreplus that turned out to be a bit thicker so the 170mm was just too high with the post all the way down into the frame. Luckily Bontrager have copied one up and now sell shims to limit dropper travel. They come in 10mm or 30mm size. You can only use one at a time but can trim them down if needed, to get the perfect extended height with the bontrager elite dropper posts. I still love the oneup seatpost on my canyon too.
 

dypark

New Member
Nov 17, 2021
4
0
Hawaii
Does anyone have measurement info for a Rail 9.7 in a Small frame? I'm hoping to move up to a 150 mm dropper from Oneup with the tube down all the way to the collar. Oneup lists an insertion depth of 237. Bike comes with a 100 mm dropper with a listed max insertion of 210.
 

irie

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May 2, 2022
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Chichester, W.Sussex, UK
Does anyone have measurement info for a Rail 9.7 in a Small frame? I'm hoping to move up to a 150 mm dropper from Oneup with the tube down all the way to the collar. Oneup lists an insertion depth of 237. Bike comes with a 100 mm dropper with a listed max insertion of 210.

From memory the OneUp dropper cable attachment is 15mm but the Bontrager cable attachment is 27. 7mm so there's more than 12mm to play with. I put a OneUp 180 dropper (without shims) in my Trek Rail 5 Large and it fitted with room to spare in spite of the fact that using Trek's insertion lengths the Oneup dropper site recommended shimming to 160mm
 
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BiGJZ74

E*POWAH Master
Subscriber
Mar 17, 2021
573
444
American Canyon, CA
From memory the OneUp dropper cable attachment is 15mm but the Bontrager cable attachment is 27. 7mm so there's more than 12mm to play with. I put a OneUp 180 dropper (without shims) in my Trek Rail 5 Large and it fitted with room to spare in spite of the fact that using Trek's insertion lengths the Oneup dropper site recommended shimming to 160mm
FAQ on insertion depths for the rail are wrong. When I got my 2020 Rail 7, the Trek Chart said large was 300mm. I run a 210mm Oneup v2 slammed to the collar on my Rail 7.
 

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