[Closed] 650b into a fox float 36 fork...

they'll go straight in, for sure - question you haven't asked is "will I die ?" (depends whether the tyre fouls the crown at full compression - in which case, v.v.slightly more likely to be "yes, soon" than if it doesn't)

Hmm I did wonder that there's not allot of room there 😯 that would be an unpleasant off

Loads of clearance for 650b in a 36. Loads.

Well if it fits in and the wheel rotates then as the crown doesnt move you wont die.

as the crown doesnt move you wont die.

I bow to wrecker's experience (I've never used or even had a proper look at a 36) but if it was me I'd fit the wheel and compress the fork with ALL air out of the chamber (can you take out the valve core ?) to be sure, esp if it was a big volume tyre

Loads of clearance for 650b in a 36. Loads.

Slight exaggeration. There are quite a few that hit the crown on full compression, which isn't really the time you want to be finding out if your wheels fit...

The lower profile smaller tyres will all fit, the newer, bigger volume stuff that's coming is unlikely to.

Well if it fits in and the wheel rotates then as the crown doesnt move you wont die.

Good luck with that, let us know how you get on.

Dales rider confusing crown with bridge
Easy done, lay off

Do you have the 36 to hand? What tyre are you running and what do you plan to run, what happens if you let all the air out and compress it fully with the 26? Now add a bit and see whats going to happen.
If your running small xc tyres then probably fine, but then you will just have the same effect as running a bigger(proper) sized tyre on the rim.

Checks forks.

[img] [/img]

Nope I was right the crown doesnt move, it stays firmly attached to the steerer and only rotates.

Now the bridge and lower legs do move.

Dales Rider. Not patronising you here. The crown doesn't move but the wheel does. On compression the wheel moves nearer to the crown. Therefor when the fork is compressed a wheel with too big a diameter can then hit the crown.

Im running spesh captain control on the front at the moment there 2.2" and theres a gap of about an inch between the tyre and the Arch

Checks forks.

Nope I was right the crown doesnt move, it stays firmly attached to the steerer and only rotates.

Now the bridge and lower legs do move.

Keep trying Einstein.

What does the tyre move towards when the suspension compresses?

I think what Dalesrider hasn't fathomed is that when the lowers move up the stanchions during compression, the bridge slides up and the crown can be exposed lower than the bridge.

Yes the bridge/tyre relationship is constant but it is the potential contact with the bottom of the crown (around the area where the steerer joins) and possibly even the underneath of the down tube that could cause a face/trail meeting. When the slider section of the fork is as high as possible at full compression the bridge sits forward of the crown/head tube allowing for this exposure.

Is that a concise enough explanation? Not trying to be patronising either....although sometimes it just happens involuntarily 😀

Oh for crying out loud! So long as the wheel (whatever its size) fits within the lowers (i.e. beneath the arch) it doesn't matter what the suspension does.

The crown and the lowers on fox forks are designed to work in concert, so under full load the inner shape of the arch assumesthe same shape as the crown.

You're both right...sort of anyway.

Oh for crying out loud! So long as the wheel (whatever its size) fits within the lowers (i.e. beneath the arch) it doesn't matter what the suspension does.

The crown and the lowers on fox forks are designed to work in concert, so under full load the inner shape of the arch assumesthe same shape as the crown.

Really?

Sure?

[img] [/img]

And the same image from the front, to show it does actually fit under the arch of the lowers.

[img] [/img]

I've got 3 sets of Fox 32s and have no problems even with a 650b wheel, I've also designed the crown for a series of Fox forks and was given detailed instruction relating to the allowable clearance.

You've got to admit, you've properly squeezed that tyre in there?!

You've got to admit, you've properly squeezed that tyre in there?!

It looks like at least one rider will live another day by reading the warnings some of you folk have mentioned on this thread!

You've got to admit, you've properly squeezed that tyre in there?!

Yes, but it was a point proving exercise - clearing the lowers arch certainly does not equal clearing the crown, by a long way as you can see & the fork isn't even bottomed out at that point.

It's a 650b Maxxis HR2, so yes, quite a big tyre, but no bigger than a Schwalbe 2.3 Hans Dampf etc.

As I said before, some tyres will work, generally the smaller stuff. However, given the OP is running a Fox 36, I don't think he'll be rocking the 2.1 XC choices 😉

Fox Float 32 150 QR15 with Halo Vapour and Pacenti Neo Moto 2.35:

[img] [/img]

Haven't got a photo of the fully compressed fork but there was still some clearance!

HTH

Fox 32s and have no problems even with a 650b wheel

Also the chances of bottoming out a set of float 36s is the same as anything coming from Mars - A million to one

Thanks chaps its looking more and more doable 😀

If you've got a Float then, worst case, you could just reduce the travel by 10mm with a spacer.

ndthornton - Member

cor that must be flexy...

Why would it be any more flexy? My 32's use a 15mm TA, so the hub-fork interface is effectively rigid, and we're only talking a 12.5mm radial difference in spoke length. I'd bet that even if you were looking for it, you'd struggle to notice ANY difference at all.

Daffy - Member

Why would it be any more flexy?

Longer lever- increase the radius of the wheel/tyre and you're increasing the leverage on the fork.

Not that it's really relevant, it's a 150mm 32 therefore flexy regardless of what wheel is in it.

Also the chances of bottoming out a set of float 36s is the same as anything coming from Mars - A million to one

Not really the time you want to be finding out your fork bottoms out on the tyre before using all of its travel though.

If you've got a Float then, worst case, you could just reduce the travel by 10mm with a spacer.

That won't work as it reduces stanchion height, not limits the last 10mm of travel.

You can bodge a bump stop to limit travel at the end of the stroke, but its doesn't really work too great as it affects the air cartridge.

Longer lever- increase the radius of the wheel/tyre and you're increasing the leverage on the fork.

even the boys at mojo are doing it

[img] [/img]

Takes all air out of all my forks, yes the Fox bottom out. Maybe I should ride them with air in.

If you've got a Float then, worst case, you could just reduce the travel by 10mm with a spacer.

Err, doesn't the spacer drop the travel when uncompressed, reducing the axle to crown measurement and therefore it will still compress to the same point on the stanchion at full travel creating the same issue 😕

That Mondraker is hideous.

I must confess the rubber band on the stanchion does regulary end up at the top? so they do just about bottom out

I never managed to bottom out my 36s - not even close - even with less than recommended pressure. For the last 20mm I reckon I would have to drop off a roof - which Im not going to do.

I am pretty lightweight though - and I have heard that post 2012 forks have a more linear air spring.

ndthornton - Member
I never managed to bottom out my 36s - not even close - even with less than recommended pressure. For the last 20mm I reckon I would have to drop off a roof - which Im not going to do.

I am pretty lightweight though - and I have heard that post 2012 forks have a more linear air spring.

You'd want to be pretty sure - the day you bottom out your forks on a big drop and the front wheel locks at the same time will be a bad, bad day.

I had something similar happen when a branch in my spokes locked my front wheel and snapped aspoke a while back. Going from full tilt down a rough, steep lose trail to sudden stop was no fun at all. Still sore.

Ok ive been to my LBS and had a look at one of the fives there with 36's on and compared a 650b wheel with it and unfortunately its no good on that fork i will almost certainly die 🙁 however i have discussed some rather naice mavic 819 tubeless wheels with them and it looks like ill be staying at 26" unless i come into some money and buy a Bronson 😀

Thank god for that..... mis-matched tiny clown wheels on a five with big forks my eyes would bleed 😉

They got a Bronson in yet ???

There getting a couple next week one black large and a med yellow and a demo day in june