Power ARC Saddle - How to setup?

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JScycle
Posts: 260
Joined: Wed Mar 08, 2017 11:41 pm

by JScycle

Berzin1 wrote:
Mon Mar 11, 2019 8:02 am
Actually, the Power Arc by Specialized (at least the one I have) specifically states to adjust the saddle 3 cm behind where you had the old one.

Chafing may be an issue if you purchased the 155mm saddle because of the width. I went with a 143 and no problems with that as of yet.

As far as getting the saddle itself level, put the frame on a stand, level the top tube, put the level on the saddle, and loosen/tighten the saddle rails accordingly until its' level.

It takes a while and could be frustrating, but once you get it you're good to go.
Are you saying the saddle rails should be parallel with the top tube?!!?!? :shock:

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rollinslow
Posts: 866
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Location: New York

by rollinslow

The way I learned it from professional fitters is to level your bike (bottom of both tires on a level surface). Then put something flat that goes across your saddle like a clipboard with a digital level on it. After a pro fit, I know that my specialized power arc should be 6 degrees downward. This angle may be different for you but probably in the few degrees downward range.
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nonamed
Posts: 153
Joined: Tue Apr 09, 2013 1:45 pm

by nonamed

rollinslow wrote:
Tue Mar 12, 2019 12:14 am
The way I learned it from professional fitters is to level your bike (bottom of both tires on a level surface). Then put something flat that goes across your saddle like a clipboard with a digital level on it. After a pro fit, I know that my specialized power arc should be 6 degrees downward. This angle may be different for you but probably in the few degrees downward range.
Gonna check what angle I have currently when I put something long and flat across saddle (starting from front to the end) . Now I measured the angle only for front part of the saddle (where it looks like it is the most 'flat') and set the angle for 0.5 degree upward (measured with recallibrated custom level app for iphone). I am testing this setting now

3phase
Posts: 124
Joined: Tue Oct 30, 2018 4:26 am

by 3phase

I have the Power Expert on my Allez, and it's on -8 Degrees. I'm not sure what the difference betwwn the Power ARC and the Power Expert is but they look the same to me :lol: What I did was trial & error until I get it right. I had difficulty adjusting the tilt but eventually found the sweet spot after the 3rd ride, and it's -8 Degrees. Now when I compared that to my Aeroad with Fizik Arione, I realized the tilt is exactly the same. I set it back also about 3cm and played with the tilt.

nonamed
Posts: 153
Joined: Tue Apr 09, 2013 1:45 pm

by nonamed

3phase wrote:
Tue Mar 12, 2019 9:46 am
I have the Power Expert on my Allez, and it's on -8 Degrees. I'm not sure what the difference betwwn the Power ARC and the Power Expert is but they look the same to me :lol: What I did was trial & error until I get it right. I had difficulty adjusting the tilt but eventually found the sweet spot after the 3rd ride, and it's -8 Degrees. Now when I compared that to my Aeroad with Fizik Arione, I realized the tilt is exactly the same. I set it back also about 3cm and played with the tilt.
8 degress measured across saddle from top to end? Downwards?

boots2000
Posts: 1394
Joined: Mon Oct 15, 2007 9:28 pm

by boots2000

I use 1.5-2 degrees of downslope- Measured from back to front.

3phase
Posts: 124
Joined: Tue Oct 30, 2018 4:26 am

by 3phase

nonamed wrote:
Tue Mar 12, 2019 10:36 am
3phase wrote:
Tue Mar 12, 2019 9:46 am
I have the Power Expert on my Allez, and it's on -8 Degrees. I'm not sure what the difference betwwn the Power ARC and the Power Expert is but they look the same to me :lol: What I did was trial & error until I get it right. I had difficulty adjusting the tilt but eventually found the sweet spot after the 3rd ride, and it's -8 Degrees. Now when I compared that to my Aeroad with Fizik Arione, I realized the tilt is exactly the same. I set it back also about 3cm and played with the tilt.
8 degress measured across saddle from top to end? Downwards?
Yup, downwards as measured on my iphone app(Measure). Did a 178km over the weekend and no complaints. Could be different to each individual

Berzin1
Posts: 238
Joined: Wed Jul 20, 2016 9:35 pm

by Berzin1

JScycle wrote:
Mon Mar 11, 2019 11:37 pm
Are you saying the saddle rails should be parallel with the top tube?!!?!? :shock:
No. When I was adjusting the saddle I just set the seat parallel to the top tube and it works great for me.

BdaGhisallo
Posts: 3278
Joined: Wed Mar 17, 2004 1:38 pm

by BdaGhisallo

Berzin1 wrote:
Thu Mar 14, 2019 3:13 pm
JScycle wrote:
Mon Mar 11, 2019 11:37 pm
Are you saying the saddle rails should be parallel with the top tube?!!?!? :shock:
No. When I was adjusting the saddle I just set the seat parallel to the top tube and it works great for me.
I guess that begs the question then as to what angle to the horizontal your top tube is?

JScycle
Posts: 260
Joined: Wed Mar 08, 2017 11:41 pm

by JScycle

Berzin1 wrote:
Thu Mar 14, 2019 3:13 pm
JScycle wrote:
Mon Mar 11, 2019 11:37 pm
Are you saying the saddle rails should be parallel with the top tube?!!?!? :shock:
No. When I was adjusting the saddle I just set the seat parallel to the top tube and it works great for me.
That's not a suggestion people should follow as that could lend them a saddle pointing tip up a looooong way. Ouch

nonamed
Posts: 153
Joined: Tue Apr 09, 2013 1:45 pm

by nonamed

boots2000 wrote:
Tue Mar 12, 2019 5:57 pm
I use 1.5-2 degrees of downslope- Measured from back to front.
It looks like the tip of the saddle is pretty much upward with this angle? Can You post some pic?

I found that Power Arc is level (on the rails) when from back to front is 7 degrees (I measured this with saddle removed and put on even glass surface).

Now on bike I set 7 degree angle measured from front to back and will test it..

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WorkonSunday
Posts: 540
Joined: Tue Jan 16, 2018 4:39 pm

by WorkonSunday

i recently set up my wife's bike with a Power Mimic Expert. we are lucky that we have a turbo trainer so this makes things quite alot easier without have to lean over the wall etc. What we found was:

A) for back/forth, when you sit on the old saddle and lean against a wall or put it on turbo, get into riding position, then use one hand to slide between your butt and saddle to feel where to sitbone lands on the saddle. this should normally close to the middle of the seatpost and near the "wing" of the saddle. This should be reference point to replicate when switching over to another saddle. 3cm for specialized is a guide line but it's essentially trying to repeat your sitbone location going to a new saddle.

B) for tilt, our seatpost allows us to loosely tighten the seatpost screws so that the saddle can move/tilt while rider is setting on it. (if you have one of those two bolts (front and rear) type, it may take a few more try and error). This is definitely a two people job. Rider on the bike, while second person observe and tighten the screws. We found that for the power mimic, it is most comfortable if you sit on it with your body straight (hands off handlebar, as if you are reaching your backpockets or playing on the phone) , and you can feel if your body weight is neutral (neither is sliding backward or forward). We did it with pedals at 3 and 9 o'clock positions, stand up, then slowly place the butt on the saddle to start to feel the pressure. Once you have the tilt balanced, the pressure should feel pretty even. We found this takes alot of stress off the arms and wrists. (my wife rides with 5mm spacer so i would say, pretty aggressive position)

The end result is that we have the saddle slides back 1cm from center (according to the markings on the rail) and, using method shown in previous posts, the angle is tilting downwards 0.4 degrees.
Some say pour 10ml water out of your bottle to save that last bit of the weight. Sorry, i go one step further, i tend to the rider off my bikes. :thumbup:
n+1...14 last time i checked, but i lost count :mrgreen:

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