Actual Rolling Diameter Question

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Pedal4life
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Pedal4life
Edited Date/Time 11/15/2017 11:55am
Some of the current 27.5 tires have so much sidewall/volume they really look close in size to a 29 but how close are they really?
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Falcon
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Falcon 11/15/2017 11:53am
11/15/2017 11:53am Edited Date/Time 11/15/2017 11:54am
They don't do bicycle tires the same way car tires are sized; in other words, width/sidewall height as percentage of width - diameter of wheel, so you'd have to get freaky with some math and the Pi constant. Since I'm no math whiz, I'm not about to do that. However, I do know that the Pivot Switchblade is made to accept a 27.5+ wheel OR a 29. I don't think there are even any frame adjustments, although I could be wrong. Therefore, the rolling diameter must be very close.
Pedal4life
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Pedal4life 11/23/2017 4:25pm
11/23/2017 4:25pm
We’ll definitely not looking for anything difficult just line the valve stem with the ground, mark the ground & then roll until valve stem is @ the ground again this from 2 of my tires there fully inflated the 1st is.
Maxxis Minion DHF 27.5x2.5wt 87.375” or 221.932cm
The 2nd tire is
Maxxis Minion DHR2 27.5x2.3 86.5625” or 219.868cm
Jsmith
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Jsmith 11/24/2017 3:43pm
11/24/2017 3:43pm
I just rolled my 29 DHF 2.3 and got 91.375". That was on a stans flow ex at 26 lbs..
'size
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'size 11/24/2017 4:06pm
11/24/2017 4:06pm
Pedal4life wrote:
We’ll definitely not looking for anything difficult just line the valve stem with the ground, mark the ground & then roll until valve stem is @...
We’ll definitely not looking for anything difficult just line the valve stem with the ground, mark the ground & then roll until valve stem is @ the ground again this from 2 of my tires there fully inflated the 1st is.
Maxxis Minion DHF 27.5x2.5wt 87.375” or 221.932cm
The 2nd tire is
Maxxis Minion DHR2 27.5x2.3 86.5625” or 219.868cm
i hope those tires aren't mounted on the same bike at the same time. without equal rolling distance who knows what's going to happen, but i'm sure it's nothing good.
Pedal4life
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Pedal4life 11/30/2017 5:22pm
11/30/2017 5:22pm
Pedal4life wrote:
We’ll definitely not looking for anything difficult just line the valve stem with the ground, mark the ground & then roll until valve stem is @...
We’ll definitely not looking for anything difficult just line the valve stem with the ground, mark the ground & then roll until valve stem is @ the ground again this from 2 of my tires there fully inflated the 1st is.
Maxxis Minion DHF 27.5x2.5wt 87.375” or 221.932cm
The 2nd tire is
Maxxis Minion DHR2 27.5x2.3 86.5625” or 219.868cm
'size wrote:
i hope those tires aren't mounted on the same bike at the same time. without equal rolling distance who knows what's going to happen, but i'm...
i hope those tires aren't mounted on the same bike at the same time. without equal rolling distance who knows what's going to happen, but i'm sure it's nothing good.
Yes there both on the same bike & running 1-2 10th’s of a inch difference front to rear is fairly common & on this bike it’s truly incredible how it corners massive grip & great speed, I went further with the front to rear differences with a narrower rim on the back also so as to keep tire profiles in the proper shape.

Building a collection of rolling diameter would be great for all of us
'size
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'size 11/30/2017 6:50pm
11/30/2017 6:50pm
Pedal4life wrote:
Yes there both on the same bike & running 1-2 10th’s of a inch difference front to rear is fairly common & on this bike it’s...
Yes there both on the same bike & running 1-2 10th’s of a inch difference front to rear is fairly common & on this bike it’s truly incredible how it corners massive grip & great speed, I went further with the front to rear differences with a narrower rim on the back also so as to keep tire profiles in the proper shape.

Building a collection of rolling diameter would be great for all of us
i was being sarcastic at the idea of two tires rolling different distances on the same bike, not their widths. guess you had to be there.
bturman
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bturman 11/30/2017 7:53pm
11/30/2017 7:53pm
Pedal4life wrote:
Yes there both on the same bike & running 1-2 10th’s of a inch difference front to rear is fairly common & on this bike it’s...
Yes there both on the same bike & running 1-2 10th’s of a inch difference front to rear is fairly common & on this bike it’s truly incredible how it corners massive grip & great speed, I went further with the front to rear differences with a narrower rim on the back also so as to keep tire profiles in the proper shape.

Building a collection of rolling diameter would be great for all of us
'size wrote:
i was being sarcastic at the idea of two tires rolling different distances on the same bike, not their widths. guess you had to be there.
Now that's funny!

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