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aight, so im comin off a double wide rim (53 mm ish) and it was wayyyyyyyyyyy to wide and hard to pedal round, so ive narrowed it down to the mavic 823 (23mm) or the 729 )29 mm) rims. they need to be pedallable and still beable to be hucked. its goin on a vp free and will be tubeless. my question to you is, is 6 mm in a rim that big of a difference? will pedal efficientcy be harmed that much?

-stevo
 

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sreiman said:
my question to you is, is 6 mm in a rim that big of a difference? will pedal efficientcy be harmed that much?
more importantly, check the weights.
100 - 200 grams of wheel weight difference is where you would start to notice. over 400 grams of wheel weight difference is huge. it depends on the application, whether or not it's too much.

basically, 1 pound of wheel weight is equivilent to 2 pounds of frame weight.

that being said, a 729 is a strong and true wheel, pretty sure it's not a tubeless rim.
if you get the 823, make sure it's a 2006, not older. the older version fails at every spoke, ask SMT. the new ones are wider and resolved this issue.
 

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I have a wheelset with 729s and another with 823s. Both are excellent rims.

If you're going to run tubeless, then run the 823s with Michelins. Otherwise I like the extra width of the 729s. The weight difference is negligible -- 823s including the nipple-holders are ~630 grams and 729s are ~675 grams. And unlike others on this board, I have had no trouble with older d3.1 and 823 rims, despite riding hard enough to break forks, 20mm hub bearings, pedals, cranks, and bottom brackets. Maybe their spoke tension was too high -- I've seen lots of Mavic rims with cracked eyelets because of this. Maybe there wasn't enough air in the tires -- low pressure kills rims, 30-35 psi works great. And casing jumps will toast any rim. And I always run double-butted spokes because their little bit of extra give makes the wheel stronger than running straight-gauge spokes (DT proved this a while ago).
 

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the 2005 823's are absolutely incredible and strong as hell.

Here are numbers:

823== 657g (UST nipples included)

729== 675g + 400 g DH tube or 350 g stans ghetto setup

823 is also more rigid because there are no holes in the outer rim
729 also would not be as secure tubeless, becuase it would not have a bead lock like 823

I would say the new 823 is very close to 729 in terms of strength, it looks like a very beefy version of the 721 in person. Go for it.
 

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Depends on which tubes you run. I run Specialized thin tubes and they are fairly light. If I were to go tubeless, I would loose nothing. UST tires are heavier and then the sealant if you want to be safe.

There is hardly any weight differnece if you use light tubes.


If you use DH tubes there is a little weight difference.
 

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kanter said:
Depends on which tubes you run. I run Specialized thin tubes and they are fairly light. If I were to go tubeless, I would loose nothing. UST tires are heavier and then the sealant if you want to be safe.

There is hardly any weight differnece if you use light tubes.

If you use DH tubes there is a little weight difference.
We all know SMTs reply
"Go Tubeless with the 823s"

the he will say

"buy something From Azonic"

j/k another factor is price, if the rims are about the same price then go for the 823s so u dont have to deal with stans no tubes stuff, wieght shouldnt be that much of an issue with either of them
 

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KonaStinky05 said:
If weight is the same between the two, tubes and tubeless, would it even be worth going tubeless?
iyt is not the same weight, but if it was i would be a "surfer" and get tubed...it would be "totally narly"
 

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urbanfreerider666 said:
We all know SMTs reply
"Go Tubeless with the 823s"

the he will say

"buy something From Azonic"

j/k another factor is price, if the rims are about the same price then go for the 823s so u dont have to deal with stans no tubes stuff, wieght shouldnt be that much of an issue with either of them
Go Tubeless with the 823s...still run the sealant though and replace it every 2 to 3 months
 

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kanter said:
Depends on which tubes you run. I run Specialized thin tubes and they are fairly light. If I were to go tubeless, I would loose nothing. UST tires are heavier and then the sealant if you want to be safe.

There is hardly any weight differnece if you use light tubes.

If you use DH tubes there is a little weight difference.
in addition to weight, tubless aloows lower tire pressure and less rollign resistance (the tube and tire are not rubbing against each other)
 

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flatulentfox said:
in addition to weight, tubless aloows lower tire pressure and less rollign resistance (the tube and tire are not rubbing against each other)
How does the tube and tire rub against each other?

How does that have anything to do with rolling resistance?

Then you run lower air pressure and ruin your rims.
 

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yeah running lite tubes is genious till you flat or rip one.

i know guys that get away with it but compared to a tubeless setup, the get about 60% of the traction.

Stans is ghey unless u need it.

Yes flatspots are a problem on tubless rims, but if you run over 20 psi, u will be fine because they have reinforced clinchers.
 

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kanter said:
How does the tube and tire rub against each other?

How does that have anything to do with rolling resistance?

.
as the tire rolls, the part that is in contact with the ground flattens and changes shape to fit the contour of the ground. as the tire changes shape, the tube does as well. two objects moving against each other results in kenetic friction. friction converts energy into heat. energy that could be better spent propelling you forward is lost as heat. thus, higher rolling resistance.
 

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j6105 said:
Stans is ghey unless u need it.

Yes flatspots are a problem on tubless rims, but if you run over 20 psi, u will be fine because they have reinforced clinchers.
if you run low air pressure...then the tire rolls over the rim at speeds and hard turns....flatspots are on all rims

Stans is good stuff......i have about 5 holes in my tire and it is all sealed
 
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