bike sizing reach&stack help

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seansis
Posts: 47
Joined: Fri Sep 23, 2016 9:58 am

by seansis

DJT21 wrote:
Thu Feb 01, 2018 1:42 pm
Is that a picture of you taken during your pedal stroke? If so, your saddle is too high; your left leg is over extended.

Just lower your saddle, you've got nothing to lose.
Oh, good. But how much to lower the saddle?
The more I lower the saddle, the more it seems to me that something is wrong. With a cadence of 100 or more, the legs break the constancy and the power is lost.

coriordan
Posts: 210
Joined: Thu Nov 16, 2017 3:30 pm

by coriordan

I take off my shoes and socks, get on the bike and then make it so my heel just reaches the pedal (on the spindle).

Then when you move your foot back so the ball of your foot is over the spindle, there is a teeeny bit of bend in the leg.
Then once you have shoes and cleat stack as well, it's generally perfect.

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bobones
Posts: 1287
Joined: Mon Aug 12, 2013 11:19 am

by bobones

Hard to see KOPS from that photo, but your saddle does look a bit high and the bars seem too far away for you. Perhaps you can make that bike fit you by moving the saddle forward and a shorter or flipped stem, but maybe you do need a smaller bike.

topflightpro
Posts: 829
Joined: Tue Jan 13, 2009 2:35 am

by topflightpro

I agree that your saddle looks high, but it is hard to tell, as your down leg is on the other side of the bike in the pic. I also cannot gauge your knee relative to pedal.

Lowering the saddle will effectively move the saddle forward, unless you slide the saddle back at the same time. That should shorten the reach and help with your knee position issues.

But remember, KOPS is a starting point and not a hard and fast rule. Some people prefer to have their knee in front of or behind the pedal spindle.

Also, the formula you referenced for setting saddle height is again a starting point. Some people need to go above or below that number.

Lastly, try rotating your hips more to improve your position on the saddle.

seansis
Posts: 47
Joined: Fri Sep 23, 2016 9:58 am

by seansis

Today I moved the saddle forward 1 cm and ride an hour.
The first 20 minutes i ride with a power of 80-100 watts, I thought that everything was fine. But as soon as I went with a power of 200+ watts, I again tried to move forward. And again started to go numb where it should not.
In addition, my hands pressed on the handlebar, they were not relaxed. I did not know where to remove them, so that it would be comfortable.
Perhaps, among other things, I needed to lower the saddle a little, tomorrow I will check this theory.
But it seems to me that I need a shorter frame ... everything comes down to this.

coriordan
Posts: 210
Joined: Thu Nov 16, 2017 3:30 pm

by coriordan

Try my method to get saddle height, then use KOPS to get saddle setback, then use the front hub method to get stem length.
I know it's incredibly crude but its somewhere to start.

I'm just struggling to understand how, at over 6ft, a 55cm frame is too big. It just does not make sense. You would be towering over it.

bobones
Posts: 1287
Joined: Mon Aug 12, 2013 11:19 am

by bobones

coriordan wrote:
Fri Feb 02, 2018 2:27 pm
Try my method to get saddle height, then use KOPS to get saddle setback, then use the front hub method to get stem length.
I know it's incredibly crude but its somewhere to start.

I'm just struggling to understand how, at over 6ft, a 55cm frame is too big. It just does not make sense. You would be towering over it.
Short torso, long legs. Similar to me. I tend to prefer a 54 to a 56 but either can fit, and I've got 2 56s, a 55 and a 54. It's hard to tell from the photo, but his head looks quite far back, his arms look quite straight, and the line from the eyes through the bars is well in front of the axle. Too much weight on the hands too. I'd try flipping the stem as a short term fix if a shorter stem or more spacers are not options. I don't believe it is impossible to get a good fit on this bike but he's got to change the setup front and back.

seansis
Posts: 47
Joined: Fri Sep 23, 2016 9:58 am

by seansis

coriordan wrote:
Fri Feb 02, 2018 2:27 pm
Try my method to get saddle height, then use KOPS to get saddle setback, then use the front hub method to get stem length.
I know it's incredibly crude but its somewhere to start.

I'm just struggling to understand how, at over 6ft, a 55cm frame is too big. It just does not make sense. You would be towering over it.
Of course, I'll try. Thank you!

I myself do not understand why I can not find a comfortable position on the bike.
But I have a friend in another city, which at an heigh of 5'10'' was able to fit on bmc slr 51 sizes (ett 530, head tube 128!).
And everything is fine with him.

seansis
Posts: 47
Joined: Fri Sep 23, 2016 9:58 am

by seansis

bobones wrote:
Fri Feb 02, 2018 2:44 pm
Too much weight on the hands too. I'd try flipping the stem as a short term fix if a shorter stem or more spacers are not options.
Yes, that's right! But why?
I do not quite understand ... if I flipping the stem, it will be higher. How does it help to relieve the load from the hands?

bobones
Posts: 1287
Joined: Mon Aug 12, 2013 11:19 am

by bobones

seansis wrote:
Fri Feb 02, 2018 2:56 pm
bobones wrote:
Fri Feb 02, 2018 2:44 pm
Too much weight on the hands too. I'd try flipping the stem as a short term fix if a shorter stem or more spacers are not options.
Yes, that's right! But why?
I do not quite understand ... if I flipping the stem, it will be higher. How does it help to relieve the load from the hands?
It will be higher and closer (due to fork angle) so you don't need to reach as far and your weight distribution will move back toward your seat.

seansis
Posts: 47
Joined: Fri Sep 23, 2016 9:58 am

by seansis

bobones wrote:
Fri Feb 02, 2018 4:34 pm
It will be higher and closer (due to fork angle) so you don't need to reach as far and your weight distribution will move back toward your seat.
Thank you. I understood.

But ... If we consider Pinarello 65.1 think 2 (53 size) as the only bicycle. Can I fit on it with my height?

coriordan
Posts: 210
Joined: Thu Nov 16, 2017 3:30 pm

by coriordan

Is it about to sell? I would concentrate on getting your current bike fit correct.

Generally speaking you should use a mix of your bum, feet (on the pedals) and core strength to carry your upper body weight. If you are hurting your hands from weight on the bars, one or more of these is wrong.

It's hard to recommend a new bike when the fit on the current bike is wrong. Get some more pictures and perhaps videos as well.

seansis
Posts: 47
Joined: Fri Sep 23, 2016 9:58 am

by seansis

coriordan wrote:
Fri Feb 02, 2018 4:59 pm
Is it about to sell? I would concentrate on getting your current bike fit correct.

Generally speaking you should use a mix of your bum, feet (on the pedals) and core strength to carry your upper body weight. If you are hurting your hands from weight on the bars, one or more of these is wrong.

It's hard to recommend a new bike when the fit on the current bike is wrong. Get some more pictures and perhaps videos as well.
I wanted to sell. But there was rather a question of profit. Pinarello has a DI2, my bike is equipped with an old mechanical Ultegra.

I'll shot photos when I find at least some comfortable position on the bike.
So I'll come back. Thank you!

bobones
Posts: 1287
Joined: Mon Aug 12, 2013 11:19 am

by bobones

Perhaps the saddle to bar drop would be too extreme for you on the Pinarello in such a small size, and you need one with a taller headtube as well as a shorter top tube.

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DJT21
Posts: 382
Joined: Sun Mar 27, 2011 7:35 pm

by DJT21

FFS, lower your saddle. I'm not surprised it feels like something is wrong as you're obviously used to cycling with a sky high saddle. You need an adaptation period.

Measure your pubic bone height, then measure it again and again. Take an average. Use the Lemond formula to find your saddle height. Then set it 10mm lower than that. It will feel low. You will get used to it. You can always raise it (3mm at a time). It is clear something is very wrong at the moment. You are shifting forward on the saddle in an attempt to shorten the reach to the pedals and the bars.

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