Mountain Bike Reviews Forum banner
1 - 13 of 13 Posts

·
Registered
Joined
·
205 Posts
Discussion Starter · #1 ·
I'm thinking about getting a 650b hardtail. I have two concerns. First, there aren't too many options for parts. White Brothers and X-Fusion are the only two companies I know of making 650b specific forks. The White Brothers is $$$$ and there isn't much out there on the X-Fusion in terms of performance and reliability. Second, if the 650b doesn't catch on, I don't want to be stuck three years from now with a frame built for an obsolete wheel size.

There seems to be a lot more options for 29ers, but at 5'6" I think it'll feel like I'm driving a truck on the single track. So, is it possible to have a frame designed for a short travel (80mm) 29er fork that'll work with 650b wheels and 26" wheels? Or will there be too much of a compromise in geometry?
 

·
Registered
Joined
·
3,825 Posts
If you are 5'6", 650b is a bit big. You should really stay with the 26". I'm 5'10". I build a frame around 650b, rode it for a year and gave up. 26" is just so much better for trailriding and my size.

Frames designed for 650b will completely suck with 26" wheels in them and vis-a-via. A 0.750" change in bb height is absolutely massive.
 

·
Registered
Joined
·
9,598 Posts
A few thoughts:

Don't be scared off by XFusion forks - they are solid reliable and good forks at a price that makes good sense too. Check out the price on the Velvets at www.bikeman.com and compare that to a similar model from Fox and you'll see what I mean.

650b has been around as a wheelsize for years and years and years, only recently has it regained some buzz in the mtb community, but people have been using them for touring bikes etc. etc. for many many years. It is highly unlikely that 650b rims will ever go away (actually I suspect you'll see more options creeping into the market place over time), and you'll also slowly but surely see more tire offerings.

Also, you might want to double check pvd's claims of a .75" inch change in bottom bracket height as I think (not 100 percent sure) he has inflated that change a bit. I think the real change is closer to a half or maybe even as low as a quarter inch difference.
 

·
Premium Member
Joined
·
7,491 Posts
Depends on the tires

It's possible to make a 650b frame work with 26" wheels, especially if you minimize the wheel radius difference (which, comparing equivalent size tires, is about 15mm) by using big 26" tires (say, big volume 2.4s or something). But it's still a significant difference in BB height. You can ask your builder to make the BB 5mm or 10mm higher than he/she thinks is optimal with the 650b wheels and split the difference, too, if you're getting a custom setup. But that's a kinda kludgey way of solving the problem - a little high or a little low but never just right.

There are a decent number of 26" and 29" fork options that will work fine with 650b wheels (well, any 29er fork is fine). The Fox is a popular 26" choice, though they officially say not to do it (the neo-moto knobs will just *barely* graze the crown when bottomed). Old Manitou Xvert (barf) will work well too. Probably others - there's a whole thread about this on the 650b board.

I'd probably just do 26" if I were super concerned about parts availability, but I'm fairly confident that we'll continue to see 650b stuff available, so I don't think you should be too worried about that problem.

Like most things in life there's no free lunch here.

-Walt
 

·
Registered
Joined
·
3,310 Posts
I not a builder, just like to look around here, but the BB height question was interesting to me.

Again, if it were a custom build, could you use an eccentric BB in the up position for 26" wheels, but rotate it 180deg to lower the BB (relative to the frame) for 650?

is the point of this that you really want both sizes, either for comparison or just different conditions, or are you concerned that 650 will go out of style and parts become less common?
 

·
Premium Member
Joined
·
48,238 Posts
Joules said:
I not a builder, just like to look around here, but the BB height question was interesting to me.

Again, if it were a custom build, could you use an eccentric BB in the up position for 26" wheels, but rotate it 180deg to lower the BB (relative to the frame) for 650?

is the point of this that you really want both sizes, either for comparison or just different conditions, or are you concerned that 650 will go out of style and parts become less common?
The EBB would work though it can be difficult to setup the front derailleur with the BB in the down position.
 

·
Non Dual Bliss
Joined
·
6,240 Posts
2 position dropouts. Halves the difference. No need to pay me but I like maple syrup, french roast coffee, and long walks on the beach holding hands.
 

·
Registered
Joined
·
647 Posts
Bah, I like 700-710mm tires the most, be they 26x2.3-4 (voluminous ones), 650bx2.0, or 700x45... As long as you can change fork lengths to correct for trail, you can make a bike that is passable with all three.... I do that with some of my frames. I design them around the 650b stuff, but they feel super carvy with 26" wheels, and a little more nimble with the 700's. I fall asleep almost everynight dreaming about being home in mass and the snow melting and carving roostly loamy corners on some Quasi-motos...
 

·
Registered
Joined
·
205 Posts
Discussion Starter · #10 ·
So it does sound like there could be some noticeable compromises in having the cake and eating it too. My concern is over parts availability. I know a lot of companies have said they're coming out with 650b stuff, but there are really just a handful of companies with actual 650b stuff and only one company (Panaracer) making a 650b mtn tire. Compare this to all the 29er offerings out there.

The other concern is what if I decide 650b just really isn't for me. Ideally I could demo a 650b, but I checked around a few shops in my area and nobody has a 650b to demo - 26" and 29er yes. That's an interesting thought on the EBB. DWF, what do you mean by two position dropouts? Are you talking about sliding dropouts?

After reading everybody's comments, I've decided to first build up a set of 650b wheels on some hubs I have lying around. I measured the clearance on a Rock Lobster (26") and it looks like the wheels will just clear. I'll demo them for a bit and if I don't like them I won't be out a whole bike.
 

·
Registered
Joined
·
2,230 Posts
Okay.

Get yourself an 80mm travel 29er fork, and a 100mm travel 26er fork.

Buy some sliding dropouts and an EBB, and put them in the same frame.

Of course, it will help if you design the thing before you do any of this, and if you do, you'll notice that you can build a single frame that can run any wheel size from 26" to 29" with surprisingly few compromises.

Well, except from the fact that it's one huge compromise.

:thumbsup:
 

·
Premium Member
Joined
·
48,238 Posts
lml1x said:
So it does sound like there could be some noticeable compromises in having the cake and eating it too. My concern is over parts availability. I know a lot of companies have said they're coming out with 650b stuff, but there are really just a handful of companies with actual 650b stuff and only one company (Panaracer) making a 650b mtn tire. Compare this to all the 29er offerings out there.
Panaracer make the tires for Pacenti, NeoMoto and Quasi Moto.
Kenda offers the Nevegal in 2.35 and 2.1
Schwalbe the Racing Ralph in 2.25
IRD is having Panaracer make a Fire XC Pro.
 
1 - 13 of 13 Posts
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top