[Green Monk]

I'm considering getting my redundant 26" ti hardtail converted into a Rohloff specific 650B.

The BB height is currently 11.8" meaning that in 650B mode it'll be around 12.55".

How will this effect the handling?

 

[DekerfTeamST]

I'm considering getting my redundant 26" ti hardtail converted into a Rohloff specific 650B.

The BB height is currently 11.8" meaning that in 650B mode it'll be around 12.55".

How will this effect the handling?

I wouldn't worry about it. My 650b specifically designed frame was built around 12.25".

 

[derby]

Actually the BB will rise to 12.3 inches. 650b axle height a 1/2 inch difference to a 26 inch wheel with the same tire model.

A higher BB raises the rider and bike weight center. There is more pedal clearance, a benefit for pedaling rocky and rooty trail. But side to side response is theoretically slowed, although I personally didn't notice any loss in cornering ability converting my bike to 650b, only the improved grip, rolling ease, and added stability overall.

Without changing wheelsize a lower BB is more stable, and easier to handle and climb on smoother trail, and rocky downhill when not pedaling.

BB height is personal preference, mainly depending on trail conditions. Rocky trail riders usually prefer higher BB's than common.

 

[Green Monk]

Actually the BB will rise to 12.3 inches. 650b axle height a 1/2 inch difference to a 26 inch wheel with the same tire model.

ok - i thought that the difference in diameter was equal to 1.5" (27.5" - 26") ?? Or have i misunderstood something??

 

[Green Monk]

I wouldn't worry about it. My 650b specifically designed frame was built around 12.25".

What length chainstays did you go for?

 

[88 rex]

ok - i thought that the difference in diameter was equal to 1.5" (27.5" - 26") ?? Or have i misunderstood something??

That's just the rough guideline. I believe most 26" tires are closer to 26.5-27"

I think the sweet spot is 12-12.5 "

 

[DekerfTeamST]

What length chainstays did you go for?

16.75"

 

[Cracked Headtube]

ok - i thought that the difference in diameter was equal to 1.5" (27.5" - 26") ?? Or have i misunderstood something??

Diameter yes, but when looking at the axle height, we're talking about the radius. Split the difference.

 

[laffeaux]

ok - i thought that the difference in diameter was equal to 1.5" (27.5" - 26") ?? Or have i misunderstood something??

Yep. But half of that change is above the wheel axle which does not affect the BB height.

There's not correct BB height, there are advantages to high BBs and advantages to having lower BBs. I personally prefer lower heights - the same on a 650b as I have on my 26er - about 11.7 inches. Find a bike (regardless of wheel size) that has a 12.3 inch BB height and ride it to see if you like it.

 

[derby]

ok - i thought that the difference in diameter was equal to 1.5" (27.5" - 26") ?? Or have i misunderstood something??

The rim diameter difference "26" to 650b is 1 inch, measured. "26" inch wheels with 2.1 tires are typically 26.5 inches, measured. 650b 2.1 are typically 27.5, measured. Tire brand and sizes vary in heights, some are taller than others. :thumbsup:

 

[Green Monk]

Thanks for all your feedback.