Max seatpost Insertion on a Rise?

[theremotejuggernaut]

Medium frame, I've got about 2" of seatpost showing and the saddle keeps hitting me in the arse.

I've got 240mm stack and looking on the One Up site, that gets me a 210mm post shimmed down to 200.

It states the insert depth as 297mm. Anyone know whether it'll go that deep in a medium frame?

I know I could pull it apart and measure and I will if necessary but if anyone has experience of this combo, it makes life easier!

 

[ebsocalmtb]

You cannot bottom out a 210mm post into a medium frame. My wife's m20 has a 180mm oneup dropper installed and in order to insert it within 3mm of fully into the seat tube, I had to clock the adjuster on the dropper post so that it did not make contact with the power button. It still makes contact with the button, but I've gotten everything to play nicely and I added a bit of clear silicone to the collar on the power button to ensure it stays in place.

From my experience, the absolute max insertion on a medium carbon rise, is about 253mm. I cannot speak to this dimension on the hydro version.

 

[Malicefox]

 

[2WheelsNot4]

Unusual seeing the maximum insertion rather than the minimum.

 

[Shjay]

I have a 210mm one up in a large M20 & cannot fully slam due to the position of the power button

 

[BiGJZ74]

Unusual seeing the maximum insertion rather than the minimum.

Max insertion is the only thing people want to know.....let's you know how long a dropper you can fit in a frame slammed to the collar. Nobody needs to know what is the max length of post that I can have sticking out of my frame on my 210mm oneup .....maybe if you're 7'8" tall.

 

[BiGJZ74]

I have a 210mm one up in a large M20 & cannot fully slam due to the position of the power button

I slammed a 210mm on my large H15 by trimming the cable endcap in half to give the cable more room to flex around power internals

 

[YokoOno]

No problem fitting the 180 OneUp dropper in my medium m20. During installation I had seatpost at max insertion although I ride with seatpost about 1" up from max.

 

[ebsocalmtb]

Fwiw, the H-series is slightly better then the M-series for max insertion per size. The power button being relocated on the H-series buys another 5mm or so of insertion. @Malicefox was right to post the blue paper links for insertion for the M-series and for those following along, I can say that I believe the data in that paper to be accurate from what I have seen on the Medium and XL M-series I own, and my buddies Large H-series.

 

[BiGJZ74]

Surprisingly max insertion is supposed to be shorter on the Rise H. I shouldn’t be able to slam a 210mm one up but I can with a slight cable end modification.

 

[theremotejuggernaut]

Cheers everyone.

After @Malicefox posted the tech sheet I was set on the 180 (cheers for that by the way).

Looking at M vs H, I can see the on/ off button is in a different place so the H gets a little more depth. I've just measured (crudely, externally) the seat tube and I can't see there being more than 260-265 of depth before the seatpost fouls on the charging socket/ wiring.

I know the insert depth of the post includes the actuator so I guess there's a chance that the actuator could sit nicely with the charging port but it's all getting a bit close at that point.

Realistically, there's no way the 210mm post is ever going to drop all the way in with a 297mm insert depth.

Using the standard 150mm post, I currently have 37mm of post above the seat clamp. With the 210 post, I'd still have 37mm of post out of the frame due to the limited depth of the seat tube. That would leave me a max 203mm extension to keep that saddle height correct. Lowest the 210 post goes is 223mm so that's a no go.

(Overall height from the top of the seat tube to saddle rails would be 260 where I need 240ish).

Looking at the 180, insert depth is 267mm. Again, it'll only go 260mm into the frame leaving 7mm sticking out. With a stack of 213mm it'll leave my saddle 20mm too low so I'd need to pull it out another ~20mm (27mm in total) to keep the saddle height.

So although I'd have a 180mm drop instead of 150, surely the saddle would end up only 10mm lower when fully dropped?.. Is 10mm worth £200? Probably not...

Someone check my maths? It's been a long day.

I need 240mm stack from the seat tube to the saddle rails

One Up Chart

Orbea Chart

I'm off to research droppers with short insert depths...

 

[BiGJZ74]

Cheers everyone.

After @Malicefox posted the tech sheet I was set on the 180 (cheers for that by the way).

Looking at M vs H, I can see the on/ off button is in a different place so the H gets a little more depth. I've just measured (crudely, externally) the seat tube and I can't see there being more than 260-265 of depth before the seatpost fouls on the charging socket/ wiring.

I know the insert depth of the post includes the actuator so I guess there's a chance that the actuator could sit nicely with the charging port but it's all getting a bit close at that point.

Realistically, there's no way the 210mm post is ever going to drop all the way in with a 297mm insert depth.

Using the standard 150mm post, I currently have 37mm of post above the seat clamp. With the 210 post, I'd still have 37mm of post out of the frame due to the limited depth of the seat tube. That would leave me a max 203mm extension to keep that saddle height correct. Lowest the 210 post goes is 223mm so that's a no go.

(Overall height from the top of the seat tube to saddle rails would be 260 where I need 240ish).

Looking at the 180, insert depth is 267mm. Again, it'll only go 260mm into the frame leaving 7mm sticking out. With a stack of 213mm it'll leave my saddle 20mm too low so I'd need to pull it out another ~20mm (27mm in total) to keep the saddle height.

So although I'd have a 180mm drop instead of 150, surely the saddle would end up only 10mm lower when fully dropped?.. Is 10mm worth £200? Probably not...

Someone check my maths? It's been a long day.

I need 240mm stack from the seat tube to the saddle rails

One Up Chart

View attachment 95585

Orbea Chart

View attachment 95586

I'm off to research droppers with short insert depths...

If your comparing the OC dropper to the One up, even a 150 One up with the collar set at the same height as the OC would be at least a half inch lower as stack height on the OneUp is much lower.

 

[theremotejuggernaut]

If your comparing the OC dropper to the One up, even a 150 One up with the collar set at the same height as the OC would be at least a half inch lower as stack height on the OneUp is much lower.

Indeed. But surely with the lower stack, the saddle would sit lower (if the collars were the same height). So to preserve my saddle height, I'd need to pull the post out by half an inch which would mean the saddle ended up at the same height when dropped?

Unless I'm looking at completely wrong which is very possible right now.

Going to the 180 post would get me an overall ~10mm lower saddle at max drop because I'd have to pull the post out of the frame to preserve my saddle height?

 

[Richridesmtb]

If you set your saddle height the same for the raised position you will get 30mm more drop with the 180mm.

The stack is only slightly different between the two posts, but one is doing a slightly higher stack with a much greater drop.

 

[Richridesmtb]

The key bit you're missing is the top of the seat height when dropped. Not the collar position.

 

[BiGJZ74]

So Stack of Oneup 180 is 213mm vs OC 150 @ 208mm which means that with Collars at equal height, A Oneup V2 with 30mm extra drop is only 5mm taller. Shows how crappy the stack height of the stock dropper is. Max insertion of M frame is 255, Oneup 180 is 267 which means you'll have ~12mm exposed at full insertion with the 180. If your collar to rails currently measures 240mm. With the One up 180 to get your same current saddle height you would need 240(desired stack) - 213mm (V2 180 stack) = 27mm of exposed post on the OneUp V2 180. Since the new collar height will be 5 mm lower than it currently is....in actuality you'll get 35mm of extra drop from the new post.

 

[theremotejuggernaut]

Right. I think I'm with you.

As @Richridesmtb says, my above post was based on the collar, not the saddle clamp.

So the way I should have looked at it is

(Stack height - drop) + seatpost extension to maintain 240mm saddle clamp height = saddle clamp height at full drop.

We get,

Orbea
(208-150)+37 = 95mm

Oneup
(213-180)+27 = 60mm

So yeah, maths would suggest that I'm wrong and @BiGJZ74 is correct with 35mm lower at full drop.

 

[neilo]

Right. I think I'm with you.

As @Richridesmtb says, my above post was based on the collar, not the saddle clamp.

So the way I should have looked at it is

(Stack height - drop) + seatpost extension to maintain 240mm saddle clamp height = saddle clamp height at full drop.

We get,

Orbea
(208-150)+37 = 95mm

Oneup
(213-180)+27 = 60mm

So yeah, maths would suggest that I'm wrong and @BiGJZ74 is correct with 35mm lower at full drop.

You shouldn't have to do any maths here. Unless one of the manufacturers is telling fibs about their product, the difference in saddle height off ground at full drop between a 180mm and a 210mm MUST be 30mm, if the saddle height off ground at full extension is the same.

 

[theremotejuggernaut]

You shouldn't have to do any maths here. Unless one of the manufacturers is telling fibs about their product, the difference in saddle height off ground at full drop between a 180mm and a 210mm MUST be 30mm, if the saddle height off ground at full extension is the same.

Yeah, but it's not the over all drop that I'm concerned with, it's the height of the saddle relative to the frame at full drop.

The longer post will have a greater drop but if the shorter post has to be pulled way out of the frame to keep the saddle height correct for pedalling, it's going to affect how high the saddle is when it's dropped.

Say we have identical bikes, one with a 200mm drop and one with a 100mm drop. If both posts were fully inserted into the frame, at full drop both saddles would be in the same place.

At full height, the 200mm post would have the saddle 100mm higher.

If we pulled the 100mm post out of the seat tube so the saddles were the same height when the posts were extended, the 100mm post is going to leave the saddle 100mm above the seat tube when it's dropped.

It's that bit which needed the maths although I'd be getting more drop overall, would the differences in stack height and pulling the post out of the frame to preserve saddle height mean I'd get a meaningful difference in saddle height at full drop?

 

[BiGJZ74]

You shouldn't have to do any maths here. Unless one of the manufacturers is telling fibs about their product, the difference in saddle height off ground at full drop between a 180mm and a 210mm MUST be 30mm, if the saddle height off ground at full extension is the same.

Only if ur talking same model seatpost that can be inserted deep enough to get same saddle height. 210mm on Ops medium fully inserted would be way taller (290mm stack) than the Ops desired 240mm stack height.. The Ops Stock Orbea 150 dropper has a really tall clamp height hence the stock Orbea 150 having a stack of 208mm vs 213mm on a oneup 180. Seat at same height one drops 150, one drops 180 but the difference is 35mm......

 

[BiGJZ74]

Comparison of the stock Orbea 170 vs an Original V1 oneup 180 (v2 has an even shallower stack at full drop). Blue line designates max insertion point of post. Green dots are center of rails.
edit—after posting you can see line of max insertion point of Orbea post is still a few mm below my blue line.

 

[neilo]

Only if ur talking same model seatpost that can be inserted deep enough to get same saddle height.

Yes that was the caveat in my post - assuming same saddle height at full extension. Which was also the OP's goal.

Seat at same height one drops 150, one drops 180 but the difference is 35mm......

This I still don't get. The stack heights don't matter (since the stack amount for a given post/saddle combo is the same at full extension as it is at full drop, all the stack height does is control how much insertion you need to get the desired max saddle height). If the drop amount is 30mm different, and the saddle heights are the same at full extension, then the saddle height at full drop WILL be 30mm different. Noting of course that for a post/saddle with a bigger stack height, you will need more insertion of the post into the frame to achieve the caveat (same saddle height at full extension). But assuming you have the clearance in the frame to achieve that for both posts, 30mm will be the difference.

For the OP - I've done exactly this on my Rise M10 size Large. Replaced the 150 OC with a 180 OneUp V2, I have the same max saddle height as before, with 30mm lower minimum saddle height at full drop . But I'm fairly tall, and so had no issues with insertion depth, I still have around 3cm of post showing with the 180 OneUp.

Happy riding!

 

[BiGJZ74]

Yes that was the caveat in my post - assuming same saddle height at full extension. Which was also the OP's goal.



This I still don't get. The stack heights don't matter (since the stack amount for a given post/saddle combo is the same at full extension as it is at full drop, all the stack height does is control how much insertion you need to get the desired max saddle height). If the drop amount is 30mm different, and the saddle heights are the same at full extension, then the saddle height at full drop WILL be 30mm different. Noting of course that for a post/saddle with a bigger stack height, you will need more insertion of the post into the frame to achieve the caveat (same saddle height at full extension). But assuming you have the clearance in the frame to achieve that for both posts, 30mm will be the difference.

For the OP - I've done exactly this on my Rise M10 size Large. Replaced the 150 OC with a 180 OneUp V2, I have the same max saddle height as before, with 30mm lower minimum saddle height at full drop . But I'm fairly tall, and so had no issues with insertion depth, I still have around 3cm of post showing with the 180 OneUp.

Happy riding!

You're right i'm an idiot lol.....

 

[HarryJune]

I have a size medium h15 rise, when original post is fully down saddle is about 2-3 cm to low at extended hight.
would the 180 OneUp V2 solve this. ( still be able to have seat slammed and gain 2-3 cm when extended)
thanks

 

[theremotejuggernaut]

I have a size medium h15 rise, when original post is fully down saddle is about 2-3 cm to low at extended hight.
would the 180 OneUp V2 solve this. ( still be able to have seat slammed and gain 2-3 cm when extended)
thanks

No. Unfortunately not. That's what I was wondering when I started the thread.

Based on specs, the 180mm OneUp post won't fit all the way into the frame as it will hit the charging socket. There will be approximately 12mm of post out of the frame (255mm depth stated, 267mm post length).

I haven't been able to find a 180mm post that will fit flush to top of the seat tube so you'll always have a bit of post showing.

I have ordered a 180mm Oneup so will be able to make some proper measurements.

I'm hoping that it'll get a bit more clearance with the saddle fully down.

To get your saddle at the correct height, you'll have to pull the post out a bit.

 

[HarryJune]

No. Unfortunately not. That's what I was wondering when I started the thread.

Based on specs, the 180mm OneUp post won't fit all the way into the frame as it will hit the charging socket. There will be approximately 27mm of post out of the frame.

I haven't been able to find a 180mm post that will fit flush to top of the seat tube so you'll always have a bit of post showing.

I have ordered a 180mm Oneup so will be able to make some proper measurements.

I'm hoping that it'll get a bit more clearance with the saddle fully down.

To get your saddle at the correct height, you'll have to pull the post out a bit.

Thanks for that, will Look forward to see how you get on.

 

[theremotejuggernaut]

So, I ordered a 180mm OneUp (Leisure Lakes have a 20% sale on Oneup stuff if anyone looking).

It hasn't arrived yet but I realised that the 150mm Oneup post on my hardtail is actually a 180...

So I didn't actually need to order a new one and the answer to saddle clearance was always sitting in the garage!

Never mind.

Anyway, a quick measure shows that fully compressed, the Orbea post (150) leaves the saddle clamp 65mm above the bottom of the collar.

The Oneup (180) leaves the saddle clamp 35mm above the bottom of the collar.

So with the Orbea post fully inserted and saddle dropped will give a saddle clamp height of 65mm above the seat tube.

With the OneUp (180) inserted as far as will will go, saddle clamp at full drop will be 47mm above the seat tube. Or a fairly limited 18mm lower over all due to needing 12mm of post out of the frame.

Where neither post is fully inserted, despite having 30mm more drop with the OneUp, the overall difference in saddle height at full drop looks to be about 25mm.

Fully dropped, the orbea post sits ~40mm above the top of the collar. The Oneup manages to reduce this to only 15mm(ish)

My measurements are only rough and until I've swapped the post over I can't be 100% but it looks like it'll get the saddle about 25mm lower at full drop.

Missus has gone shopping so currently on dad duties but if I have time later, I'll swap them over.

 

[theremotejuggernaut]

Well, I finally got around to fitting the 180mm OneUp post this afternoon.

First thing to report is that the overall length of the post below the collar was almost exactly the same as the Orbea 150mm post.

I was able to fully insert the 180 into my medium sized H.

It did get tight about 2 inches off full insertion but measuring measuring measuring proved that it would fit.

The rule bottomed out on the plastic housing of the charge socket at just shy of 280mm.

With the post fitted and my original stack height of 240mm (seat clamp to middle of saddle rails) I now get a saddle rail height of 55mm at full drop. The Orbea post left me with 95mm so I've gained (lost?) 40mm by swapping.

That doesn't tally with any of the calculations that I did earlier but the new post has done what I wanted.

I guess looking at it now, I've gained 30mm from the extra drop plus 10mm(ish) from a reduced collar to clamp height of the oneup post?

@HarryJune this might mean that a 180 post will work for your requirements. I think the only way to be sure would be to pull the post out and measure how deep you can go before you hit the charge socket.

Cheers for everyone's help! I'm still quite sure how the numbers have worked but they did!

 

[HarryJune]

Great, that’s exactly what I wanted to know. Thanks

 

[neilo]

With the post fitted and my original stack height of 240mm (seat clamp to middle of saddle rails) I now get a saddle rail height of 55mm at full drop. The Orbea post left me with 95mm so I've gained (lost?) 40mm by swapping.

That doesn't tally with any of the calculations that I did earlier but the new post has done what I wanted.

I agree this doesn't tally. If your full stack height at full extension is 240mm from clamp, the Orbea (nominal 150mm drop) should be at 240 - 150 = 90mm at full drop and the OneUp (nominal 180mm drop) should be at 240 - 180 = 60mm at full drop. So what you're measuring is saying that the Orbea is actually a 145mm drop and the OneUp is actually 185mm drop! I suspect some measurement inaccuracy is creeping in.

I just went out to the shed and did the same measurement on mine (OneUp 180), it's set at 246mm above clamp at full extension and hits exactly 66mm at full drop - 246 - 66 = 180mm.