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Discussion Starter · #1 ·
Ok simple question

Going from 27.5x3 in front to 29x2.6 is about one degree slacker angle which is not good to roll but at the same time you’re running bigger diameter wich is good to roll

So with this new setup is going to roll faster slower equally?

Thanks!
 

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Discussion Starter · #3 ·
Why is slacker not good to roll?
As far I know xc bikes are about 69 slack vs the 66 of enduro

However let's no get in other sub-thread

You got a 27.5x3 bike with 69 slack angle, you put some 29x2.6 front that gives now 68 but you get more diameter

It's going to roll faster slower or same?
 

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It will roll faster because 29ers roll faster than 27.5 x 3s.

Slacker does not make a bike roll slower, in general terms it makes it less manueverable but adds stability (for going faster) in return. However, no offroad bike should be on a 69 degree HTA regardless of the application imo so I don't see even a loss in manueverability going to a 68 HTA.

The only negative I'm seeing is the slacker STA and maybe the increase in the BB height.

Good luck.
 

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g=9.764m/s2
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Right, wheel diameter and tire rolling resistance have the greatest impact on speed. Just try different things and see what works for you. Guerrilla Gravity bikes now have a GeoAdjust headset which includes a 0 and 15mm lower cup to encourage the rider to try different reach, wheelbase, and stack height to find what works best for them. I put a 15mm lower cup on my ‘14 Stache to slacken it and enjoy the stability going down and everywhere my full squish goes.
 

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Discussion Starter · #6 ·
It will roll faster because 29ers roll faster than 27.5 x 3s.

Slacker does not make a bike roll slower, in general terms it makes it less manueverable but adds stability (for going faster) in return. However, no offroad bike should be on a 69 degree HTA regardless of the application imo so I don't see even a loss in manueverability going to a 68 HTA.

The only negative I'm seeing is the slacker STA and maybe the increase in the BB height.

Good luck.
Hey men thanks for you answer

You mean it's going to be more hard to handle in tight turns for example?
 

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Discussion Starter · #7 ·
Right, wheel diameter and tire rolling resistance have the greatest impact on speed. Just try different things and see what works for you. Guerrilla Gravity bikes now have a GeoAdjust headset which includes a 0 and 15mm lower cup to encourage the rider to try different reach, wheelbase, and stack height to find what works best for them. I put a 15mm lower cup on my '14 Stache to slacken it and enjoy the stability going down and everywhere my full squish goes.
is there a headset that allows to get steeper? I don't want to go any slacker
 

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There are angle headsets but they are generally designed to slacken. Realistically the difference in 27.5x3 vs 29x2.6 diameter is nominal and increasing fork sag is enough to compensate for maintaining current ride height geometry. Try not to overthink this...maneuverability is most useful in slow technical XC style climbing where 80mm-100mm short travel forks are the norm. So if your intention is for this to be an XC climbing machine, shortening your fork ride height may accomplish this, especially if your mid-phat has a 120mm fork.

is there a headset that allows to get steeper? I don't want to go any slacker
 

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Discussion Starter · #9 ·
There are angle headsets but they are generally designed to slacken. Realistically the difference in 27.5x3 vs 29x2.6 diameter is nominal and increasing fork sag is enough to compensate for maintaining current ride height geometry. Try not to overthink this...maneuverability is most useful in slow technical XC style climbing where 80mm-100mm short travel forks are the norm. So if your intention is for this to be an XC climbing machine, shortening your fork ride height may accomplish this, especially if your mid-phat has a 120mm fork.
Oh then is ok, no im not interested in that stuff i ride wide trails, high speed confidence and a better rolling for long distances is my target

Yes seems that that 29er in the front its going to be nice to me and my bike just as a freeze beer in a hot day
 
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