It is important to not look at reach and stack in isolation, how the bike fits will be a combination of both factors. The Evo is certainly going to be a more upright position than the hardtail as they are currently set up. Good news is that you have some spacers you can remove and plenty of room to go for a longer stem than 60mm if you want a more familiar set up.
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As for the front end height, youâve got several spacers you can remove. Also, on the hardtail, youâve got a pretty long stem thatâs flipped upside down. And the bars on the EVO have some significant rise to them. Removing the spacers, flipping the stem and swapping the bars to something flatter would get you pretty close to your last stack height.
But also, make sure youâre comparing the stack from your pedaling position, not just from the ground. With the rear travel of the Full Sus itâs definitely possible that the BB is higher off the ground making the saddle and bar heights appear much higher than they would feel when sitting on the bike.
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Super key to look at delta from the BB. Ground measurements are nearly worthless when comparing HT to FS.
With respect to fit, most dimensions should start at the BB and then from the saddle (one set relative to the BB of course) to the bars.
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You canât compare the bikes sitting side-by-side. The geometry changes once loaded are very different between a 1000mm HT and a 120mm FS bike. With the HT, as you load it with your weight, the whole bike rotates around the rear axle. With the FS bike, assuming roughly equiv sag front and rear, the whole bike moves down (less change in reach and stack vs the HT).
And as mentioned a few comments up, you might find youâre faster through the rough stuff in a more upright position. But, it will feel weird and take some time to adjust.
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For reference, here are the closest bikes I can find on BikeInsights.
- Compared at BB origin:
- Compared at Ground:
Keep in mind these are likely unweighted and as mentioned, sag differences between an HT & FS will tweak these values in notable ways. Most important is that the HT sagged front only will effectively drop the bars and lengthen reach to name some bigger deltas.
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Thanks all, as many of you have pointed out, a lot of potential pit falls here! I was quite aware that I wouldnât be able to compare side my side but even recognising that my centre of gravity will be higher and further from the ground is useful to think about.
If anyone has any suggestions on how to measure and setup the full travel vs the hard tail two Iâd be super interested and grateful. The sort of thoughts Iâve had:
- Should I set my saddle setback with some sag applied (seems to make sense since Iâll be sitting)
Measure bb height and bar height, or take these calculators and figure out how they compare at sag. For full sus I always set saddle setback and angle at sag, because it changes substantially. Itâs a big fiddly to do well though.
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Put bike in trainer (or stand), get on, and use the o-rings on the shock/fork to see where it sags. Once off, you can let air out of both until the bike is pre-sagged. Of course, this assumes you know how much sag you want (which you probably donât yet). This also assumes you can and should replicate your HT or road position on the FS - Iâd wager you canât/donât want to.
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I appreciate thereâs a bunch of replies below mine I havenât read yet, but at the risk of repeating something thatâs been said, you will gain some reach by dropping the stem down the steerer.
On the PB pod, Dario discussed how he likes to get as big a frame as possible and slam the stem. Getting as much of the intended reach from the frame as possible. Using riser bars to regain any stack needed. It all.
I think you want to focus on measuring all the contact points consistently. It may also pay to try the âtallerâ position before you decide itâs wrong.
Judging from your photos, you run a lot of setback on your saddle, and have short legs/long torso. Make sure you get the saddle set to the same position from the BB for the seat bone sites (assuming same cranks/pedals), them set the bars relative the BB as well.
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I think just set your saddle position to the BB (assuming same crank length and pedals used for a known GOOD fit). The BB is connected rigidly to the seat tube.
Sag, in my opinion, should only really come into it if youâre looking at drivetrain/clearance issues, and obviously suspension setup.
The notable issue here is:
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Sagging a HT (front only drops) so the entire bike pitches forward and steepens all angles, shortens reach and saddle fore-aft vs unweighted.
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Sagging a FS (both ends drop) so then entire bike lowers. Any angle change is a result in the delta between front and rear sag. Most people sag the rear more than the front, which means the bike slackens all angles, lengthens reach and saddle fore-aft vs unweighted.
So, the simple act of sagging each bike may well move them in opposite directions. The simple act of setting saddle fore-aft, not to mention functional reach to the bars and even saddle to bar drop. Could be hair splitting for many, but some riders may well need to take all that into consideration and adjust as desired.
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I think if youâre setting up the bikes with so much more sag in the rear that you can see it leaning backwards then something needs fine tuning. Obviously only one manâs opinion and everyone rides differently.
I hear what youâre saying though, especially comparing HT to FS. He hasnât measured in Sag on the HT though, I think the simplest option here is to set it as it sits. Weâre talking a matter of a few mm between ends.
Itâs a starting point at least and a good place to go when still wrapping your head around position/set up measuring.
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I see a range of 10-20% front sag and 20-30% rear sag as common recommendations.
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Then consider that front sag as measured at the angled stanchions is less in pure vertical displacement. That is in contrast to what I think is more vertical sag direction at the rear with most suspensions. That means you have two factors (angle & amount) where the front will drop less than the rear in a typical setup.
What is your sag value method?
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That is the key reason Iâm harping on the deltas. Marginal gains/differences and all that since we live that ethos here
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HT to HT and FS to FS are not as big of a deal generally speaking. In this case, we are taking that HT to FS swap, along with changes in travel where the FS will drop more and change angle less/differently than the HT (pending what he ran as sag in the first place as you note).
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I only use sag for the initial set up to get in the ball park, then adjust pressure to get the right suspension performance.
Mineâs pretty even at 25% front and rear.
I agree with what youâre saying in terms of if you really want to get into the weeds, you can dial in your position for actual riding. Renus hasnât nailed down measuring his position as it is though so I think starting with a static position first makes sense.
Youâre far more versed in bike fit than me, but I think given a decent suspension set up and if we assume sag to be closed enough in terms of vertical distance, static is a better than decent way of doing it.
Itâs an interesting discussion though.
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