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New bike fit
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Looking to buy this Specialized Shiv if I can convince myself it fits. I'm pretty comfortable but for racing I think the front end could go lower. At 94.5 degrees hip angle, how much tighter would be recommended. Am I far off anywhere?

Geoff from Indy
http://www.tlcendurance.com
Last edited by: geoffreydean: Feb 5, 20 18:15
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Re: New bike fit [geoffreydean] [ In reply to ]
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Maybe it's browser related, but I see no picture. I see an icon for a graphic, but that's it.

To breathe, to feel, to know I'm alive.
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Re: New bike fit [Tsunami] [ In reply to ]
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I see it on my iPhone.
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Re: New bike fit [geoffreydean] [ In reply to ]
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Well, look - if you're asking "does this bike fit?/can I go lower?" the answer is yes of course you can simply remove some of the arm pad pedestal and voila, you're lower. They only issue you might face is not the 94.5 degree hip angle but the hip angle when that leg is at the top of the pedal circle - and that brings us to the two critical questions as it relates to this bike purchase:
1) How long 'dem cranks?
2) Are you willing to pony up for shorter ones?

Ian

Ian Murray
http://www.TriathlonTrainingSeries.com
I like the pursuit of mastery
Twitter - @TriCoachIan
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Re: New bike fit [Traket92x] [ In reply to ]
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yep, me too. oh well, it was a guess as to there being 42 views but no responses at the time I first saw it.

To breathe, to feel, to know I'm alive.
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Re: New bike fit [ianpeace] [ In reply to ]
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ianpeace wrote:
Well, look - if you're asking "does this bike fit?/can I go lower?" the answer is yes of course you can simply remove some of the arm pad pedestal and voila, you're lower. They only issue you might face is not the 94.5 degree hip angle but the hip angle when that leg is at the top of the pedal circle - and that brings us to the two critical questions as it relates to this bike purchase:
1) How long 'dem cranks?
2) Are you willing to pony up for shorter ones?

Ian

So to understand your reply, @ 94.5 degrees, I'm bumping up against the limit? But if I get a 170 or so crank, I can go lower? And yes there are a bunch of spacers on the front end that can come out, but I'm wondering more about not getting too pinched.

Geoff from Indy
http://www.tlcendurance.com
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Re: New bike fit [geoffreydean] [ In reply to ]
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Have you considered 150mm or 160mm cranks?
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Re: New bike fit [geoffreydean] [ In reply to ]
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Looking at your bike position relative to my recent bike fit: You are sitting further back than me, my hip is almost directly above the centre of the crank. If you sit further forward, you would rotate your body forewards, and would have a lower pad position, while mataining roughly the same hip angle. I am 173cm (5'8'') tall and use a 165 crank, as others have said a shorter crank would help open the hip a little.
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Re: New bike fit [geoffreydean] [ In reply to ]
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geoffreydean wrote:
ianpeace wrote:
Well, look - if you're asking "does this bike fit?/can I go lower?" the answer is yes of course you can simply remove some of the arm pad pedestal and voila, you're lower. They only issue you might face is not the 94.5 degree hip angle but the hip angle when that leg is at the top of the pedal circle - and that brings us to the two critical questions as it relates to this bike purchase:
1) How long 'dem cranks?
2) Are you willing to pony up for shorter ones?

Ian

So to understand your reply, @ 94.5 degrees, I'm bumping up against the limit? But if I get a 170 or so crank, I can go lower? And yes there are a bunch of spacers on the front end that can come out, but I'm wondering more about not getting too pinched.

There’s no limit, there is no spoon. Ignore the angles. Comfort, power, aerodynamics.

Your fit is not optimal. If it were, you’d normalize hip angle as you optimized, which would probably result in the proper length cranks for that position and your power output and use case, ie shorter cranks, as well as a normalized reach, UCI rules dependent.

Eric Reid AeroFit | Instagram Portfolio
Aerodynamic Retul Bike Fitting

“You are experiencing the criminal coverup of a foreign backed fascist hostile takeover of a mafia shakedown of an authoritarian religious slow motion coup. Persuade people to vote for Democracy.”
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Re: New bike fit [geoffreydean] [ In reply to ]
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Quote:
Well, look - if you're asking "does this bike fit?/can I go lower?" the answer is yes of course you can simply remove some of the arm pad pedestal and voila, you're lower. They only issue you might face is not the 94.5 degree hip angle but the hip angle when that leg is at the top of the pedal circle - and that brings us to the two critical questions as it relates to this bike purchase:
1) How long 'dem cranks?
2) Are you willing to pony up for shorter ones?

Ian
So to understand your reply, @ 94.5 degrees, I'm bumping up against the limit? But if I get a 170 or so crank, I can go lower? And yes there are a bunch of spacers on the front end that can come out, but I'm wondering more about not getting too pinched.

Geoff,

How long are those cranks? Look on the inside of the crank arm, near the pedal axle hole and you're gonna see a number like 175 or 172.5 or 170 or some such.

Ian Murray
http://www.TriathlonTrainingSeries.com
I like the pursuit of mastery
Twitter - @TriCoachIan
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Re: New bike fit [ianpeace] [ In reply to ]
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ianpeace wrote:

Quote:

Well, look - if you're asking "does this bike fit?/can I go lower?" the answer is yes of course you can simply remove some of the arm pad pedestal and voila, you're lower. They only issue you might face is not the 94.5 degree hip angle but the hip angle when that leg is at the top of the pedal circle - and that brings us to the two critical questions as it relates to this bike purchase:
1) How long 'dem cranks?
2) Are you willing to pony up for shorter ones?

Ian
So to understand your reply, @ 94.5 degrees, I'm bumping up against the limit? But if I get a 170 or so crank, I can go lower? And yes there are a bunch of spacers on the front end that can come out, but I'm wondering more about not getting too pinched.


Geoff,

How long are those cranks? Look on the inside of the crank arm, near the pedal axle hole and you're gonna see a number like 175 or 172.5 or 170 or some such.

Hey Ian! Yes, they're 175's. I'll look for something shorter.

I've always been more comfortable in the traditional TT position than most people. John Cobb did a quick look at my position years ago in his shop and said I had flexible hips or small stomach or something. I didn't know I had any flexible parts, but getting back to my original question. I was kind of looking for a general guide for the angles so I could work towards them - try them - and adjust for comfort and power. I don't think I could be too crazy far off because I did a 50 mile ride Tuesday and was pretty darn comfortable even for a 62 year old with a spacer in my c7 vertebrae and tight shoulder from rotator cuff surgery.

Geoff from Indy
http://www.tlcendurance.com
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Re: New bike fit [geoffreydean] [ In reply to ]
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Hey Ian! Yes, they're 175's. I'll look for something shorter.

I've always been more comfortable in the traditional TT position than most people. John Cobb did a quick look at my position years ago in his shop and said I had flexible hips or small stomach or something. I didn't know I had any flexible parts, but getting back to my original question. I was kind of looking for a general guide for the angles so I could work towards them - try them - and adjust for comfort and power. I don't think I could be too crazy far off because I did a 50 mile ride Tuesday and was pretty darn comfortable even for a 62 year old with a spacer in my c7 vertebrae and tight shoulder from rotator cuff surgery.

Geoff,

Now we've got some good data!!!

Get a 165 crank - I don't care if it's used (new rings though), if it's 105 or DA, if it's alum or carbon - Just as long as it's 165. You could probably go even shorter and Cobb has some GREAT new cranks that are 160, 155, etc. This will allow you to go lower BUT you can't do too low (nor do you really need to) because of C7 issue: when you go lower you have to crane neck up higher to look forward. Keep in mind when you move from a 175 to a 165 crank your seat height needs to go up 10mm so right there you've already got 10mm more drop to arm pads so ride that for a while FIRST then decide if you want to go lower in the front end. Also - stop chasing the body angle numbers and start playing with the 2-3mm here and there in terms of COMFORT not angles.

Ian

Ian Murray
http://www.TriathlonTrainingSeries.com
I like the pursuit of mastery
Twitter - @TriCoachIan
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Re: New bike fit [ianpeace] [ In reply to ]
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ianpeace wrote:
Quote:
Hey Ian! Yes, they're 175's. I'll look for something shorter.

I've always been more comfortable in the traditional TT position than most people. John Cobb did a quick look at my position years ago in his shop and said I had flexible hips or small stomach or something. I didn't know I had any flexible parts, but getting back to my original question. I was kind of looking for a general guide for the angles so I could work towards them - try them - and adjust for comfort and power. I don't think I could be too crazy far off because I did a 50 mile ride Tuesday and was pretty darn comfortable even for a 62 year old with a spacer in my c7 vertebrae and tight shoulder from rotator cuff surgery.


Geoff,

Now we've got some good data!!!

Get a 165 crank - I don't care if it's used (new rings though), if it's 105 or DA, if it's alum or carbon - Just as long as it's 165. You could probably go even shorter and Cobb has some GREAT new cranks that are 160, 155, etc. This will allow you to go lower BUT you can't do too low (nor do you really need to) because of C7 issue: when you go lower you have to crane neck up higher to look forward. Keep in mind when you move from a 175 to a 165 crank your seat height needs to go up 10mm so right there you've already got 10mm more drop to arm pads so ride that for a while FIRST then decide if you want to go lower in the front end. Also - stop chasing the body angle numbers and start playing with the 2-3mm here and there in terms of COMFORT not angles.

Ian

Ian, Right on. What great information! Thanks. I'll figure out tonight what BB I have and start my search for a crankset.

Geoff from Indy
http://www.tlcendurance.com
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Re: New bike fit [geoffreydean] [ In reply to ]
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Good advice given to you here. I would only add that I would go shorter than 165. With Shimano making a 105 series in 160mm, that is where I would look.
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