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long travel wagon wheelers

March 26, 2018, 11:41 a.m.
Posts: 1102
Joined: Sept. 30, 2006

Posted by: pedalhound

Not usually an Ibis fan...but that's a nice looking bike. Too bad about the short seat tube...grrrrr...

Not to mention the slack STA.  I still really wonder how they measure that at a 76-77 degree STA.  16.5" seat tube on a large is rediculous.

March 26, 2018, 12:41 p.m.
Posts: 367
Joined: Jan. 31, 2005

If the published ESTA is the same across sizes then it's probably measured at the seat collar. Which means that for an XL rider it's much much slacker than that at pedaling height. It's like they resisted modernizing their geo for so long and now they've delivered half measures.

March 26, 2018, 2:16 p.m.
Posts: 1102
Joined: Sept. 30, 2006

Posted by: craw

If the published ESTA is the same across sizes then it's probably measured at the seat collar. Which means that for an XL rider it's much much slacker than that at pedaling height. It's like they resisted modernizing their geo for so long and now they've delivered half measures.

If you look at their geometry diagram, it looks as though they measure STA at the intersection of a line drawn up from the BB, passing the back of the ST and intersecting with the reach line if it were extended back beyond the stack/reach intersection.  Since the BB is a fair distance behind the ST, this gives a pretty bad indication of what the actual STA will be.

March 26, 2018, 2:29 p.m.
Posts: 367
Joined: Jan. 31, 2005

The main takeaway is that this isn't a steep seat tube angle.

March 27, 2018, 4:01 p.m.
Posts: 79
Joined: July 5, 2010

Actually I think we've come to the conclusion that it IS a steep seat tube.  Its been mentioned in a couple spots, I think I heard it in Jeff K-W's YouTube broadcast, that Ibis measured seat tube angle at different extensions depending on frame size, XL was at 810mm, L at 770 I believe.

March 28, 2018, 7:26 a.m.
Posts: 367
Joined: Jan. 31, 2005

Agreed. Looks like they do vary their STA so that it yields the same ESTA across sizes. Good for them!

March 28, 2018, 11:33 a.m.
Posts: 696
Joined: March 18, 2017

Any bike without  75˚+ actual STA is unridable today.

March 28, 2018, 1:32 p.m.
Posts: 367
Joined: Jan. 31, 2005

Pretty much.

March 28, 2018, 3:11 p.m.
Posts: 1102
Joined: Sept. 30, 2006

Posted by: robnow

Actually I think we've come to the conclusion that it IS a steep seat tube.  Its been mentioned in a couple spots, I think I heard it in Jeff K-W's YouTube broadcast, that Ibis measured seat tube angle at different extensions depending on frame size, XL was at 810mm, L at 770 I believe.

Have we decided that?  Sure the ESTA is measured to each frame size, that is a start.  The Actual STA on the other hand is not as steep as they claim given the information from the review that was posted here on NSMB.

March 28, 2018, 3:35 p.m.
Posts: 367
Joined: Jan. 31, 2005

From Hans Heim, CEO of Ibis: https://www.pinkbike.com/news/first-ride-ibis-ripmo-long-travel-29er.html


 Last edited by: niels@nsmb.com on March 28, 2018, 3:51 p.m., edited 5 times in total.
Reason: fixed the image for you
March 29, 2018, 8:53 a.m.
Posts: 9180
Joined: Nov. 19, 2002

I kinda like that...but it's different from the rest of the industry...maybe something they should talk about more in their marketing stuff. Thanks for posting the info Craw!

March 29, 2018, 9:17 a.m.
Posts: 367
Joined: Jan. 31, 2005

Posted by: pedalhound

I kinda like that...but it's different from the rest of the industry...maybe something they should talk about more in their marketing stuff. Thanks for posting the info Craw!

All the other frame measurements are standardized except for ESTA. Ideally ESTA would be the angle of the line that passes through the BB center, the back or center of the seat tube and intersects with the Reach line. That would give a size-specific number.

March 29, 2018, 11:48 a.m.
Posts: 1102
Joined: Sept. 30, 2006

Posted by: craw

Posted by: pedalhound

I kinda like that...but it's different from the rest of the industry...maybe something they should talk about more in their marketing stuff. Thanks for posting the info Craw!

All the other frame measurements are standardized except for ESTA. Ideally ESTA would be the angle of the line that passes through the BB center, the back or center of the seat tube and intersects with the Reach line. That would give a size-specific number.

Why can it not be a line that passes through the centre of the seat tube? If bottom brackets and seat tubes all lined up like they did back in the hardtail days, then drawing a line through the BB would make sense.  Most seat tubes are more or less straight these days, so having to deal with wildy bent or interrupted ones is not really a factor is it?  BBs offset behind the seat tube make for exaggerated ESTAs when measured as you propose above.


 Last edited by: shoreboy on March 29, 2018, 11:53 a.m., edited 1 time in total.
March 29, 2018, 12:05 p.m.
Posts: 367
Joined: Jan. 31, 2005

Posted by: shoreboy

Posted by: craw

Posted by: pedalhound

I kinda like that...but it's different from the rest of the industry...maybe something they should talk about more in their marketing stuff. Thanks for posting the info Craw!

All the other frame measurements are standardized except for ESTA. Ideally ESTA would be the angle of the line that passes through the BB center, the back or center of the seat tube and intersects with the Reach line. That would give a size-specific number.

Why can it not be a line that passes through the centre of the seat tube? If bottom brackets and seat tubes all lined up like they did back in the hardtail days, then drawing a line through the BB would make sense.  Most seat tubes are more or less straight these days, so having to deal with wildy bent or interrupted ones is not really a factor is it?  BBs offset behind the seat tube make for exaggerated ESTAs when measured as you propose above.

I think I agree. So what if you drew a line from BB center to the center of the seatpost head at 4 different extensions (one for each size, or 6 if the brand makes XS or XXL) and took the angle of that? i.e. not involve the seat tube itself at all. Seeing how wildly those numbers varied would tell you a lot about how the bike fit.

March 29, 2018, 1:52 p.m.
Posts: 1102
Joined: Sept. 30, 2006

Posted by: craw

Posted by: shoreboy

Posted by: craw

Posted by: pedalhound

I kinda like that...but it's different from the rest of the industry...maybe something they should talk about more in their marketing stuff. Thanks for posting the info Craw!

All the other frame measurements are standardized except for ESTA. Ideally ESTA would be the angle of the line that passes through the BB center, the back or center of the seat tube and intersects with the Reach line. That would give a size-specific number.

Why can it not be a line that passes through the centre of the seat tube? If bottom brackets and seat tubes all lined up like they did back in the hardtail days, then drawing a line through the BB would make sense.  Most seat tubes are more or less straight these days, so having to deal with wildy bent or interrupted ones is not really a factor is it?  BBs offset behind the seat tube make for exaggerated ESTAs when measured as you propose above.

I think I agree. So what if you drew a line from BB center to the center of the seatpost head at 4 different extensions (one for each size, or 6 if the brand makes XS or XXL) and took the angle of that? i.e. not involve the seat tube itself at all. Seeing how wildly those numbers varied would tell you a lot about how the bike fit.

That is an interesting idea too.  It wasnt what I was getting at though.  Take the BB out of it (unless it is inline with the seatpost), and draw a line straight down the seatpost.  Where it intersects with the imaginary horizontal line to the dropout is your STA.  Please let me know if I am missing something, because this seems too obvious to me.

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