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Some questions

890 views 6 replies 4 participants last post by  skidad 
#1 ·
So after reading a bunch of the threads on here after hearing about 650b from the guy at my LBS, I'm convinced I want to at least go 650b front. I don't think it will clear the rear.

Here's my question, the 09 Compulsion has a HA of 69, but I noticed the 11 has a 67.5.

Right now I have a 140mm front fork, but was thinking over going 150mm to balance it out with the rear, adding a 650b it seems would get me close to the 67.5 the new frame is at?

Opinions?

Also any way to measure and see if a 650b would clear the rear?
 
#2 ·
I would just go for the front wheel to start.
You get most of the benefits of the larger wheel (relative to going 650b f/r) and slacken things out like you are trying to do.

Be sure to tweak your position slightly...slide saddle forward (maybe 1cm) and lower stem (ideally move a spacer form below to above on steerer).

As far as checking the rear, I would recommend getting your hands on an actual rear wheel to try, if you cannot get sound evidence it will work. Too much to invest based on measurements taken from the inter-web. CS length alone is not the way to check.
Also, having a 650b rear will not slacken the steering.
Good luck.
It worked like a charm on my blurXC.:thumbsup:
 
#3 ·
Adding 10mm to A/C height (140-150 fork) will slacken the head angle approx. 1/2 degree.

From the measurments I took from my new 650B front wheel it seems in reality it's only 3/4" larger in overall diameter than a 26" so that's about another 19mm.

19 +10 = 29mm so yeah about 1.5 degrees from your 69 and your at 67.5 degrees.

My Prophet was 69 degrees also with a 140mm Fox fork (can be set at 67.5 as well but I always left it at 69) and adding the 650B wheel has been fantastic. Everything is better IMO with no negatives. I haven't touched any cockpit setting although I may remove a spacer under the stem to see how that feels at some point. Right now I'm totally happy and money well spent.

Stans Flow with Neo-Moto 2.3
 
#7 ·
Thanks, and I hope so. The bike will/is more capable than myself LOL but I'm having fun with this and the 650B front was a very nice improvement. If the back is 1/2 as good I'll be stoked. Now if that Hadley would just ship :madman:

Next up will be suspension improvements to compliment the 650B setup. :D
 
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