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Full Tilt Boogie
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Discussion Starter · #1 ·
Hi guys. Here's a few teaser shots and some info on the 36er I've designed. I will be posting more in depth info after QBP's Frostbike this weekend. Enjoy!

Wheelbase: 46 inches.
Weight: 36 lbs, (with full Surly flask and holder!)
Chainstay length: 520 mm
Drivetrain: 3 X 6, 20-90 gear inches
Standover height: 30.5 inches
Top tube length: 24.5 inches

Pic #1: A line up of 26", 29", and 36" wheels featuring the local Titus rep.
Pic #2: Photo of the bike next to an 18" Salsa El Mariachi for size comparison.

My first impressions, it's more fun than I possibly imagined!
 

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Recovering couch patato
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Yeah, finally pics of a purposely-designed 36" MTB, props for having it done!!

Please do share any info and pics, details!!!
 

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holy poo

I have seen the Cokers before...but when you put it next to the 29er, the 29er looks like a little bitty bike...the difference is remarkable...looks like a 29er next to a BMX bike in terms of tire size.

Love to see more of that frame though.

Too bad you have a very limited selection of tires....at this point....
 

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Full Tilt Boogie
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Discussion Starter · #4 ·
There is only one tire actually. Coker tires no longer fit Airfoil aluminum rims. We've figured out how to cut our own tread into the slick TA tires easily enough, it actually yields a tire that is over a lb lighter than the Coker, and the tread is much better. The grip so far is unbelievable!
 

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Hike it or Bike it!
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287 Posts
benwitt11 said:
Hi guys. Here's a few teaser shots and some info on the 36er I've designed. I will be posting more in depth info after QBP's Frostbike this weekend. Enjoy!

Wheelbase: 46 inches.
Weight: 36 lbs, (with full Surly flask and holder!)
Chainstay length: 520 mm
Drivetrain: 3 X 6, 20-90 gear inches
Standover height: 30.5 inches
Top tube length: 24.5 inches

Pic #1: A line up of 26", 29", and 36" wheels featuring the local Titus rep.
Pic #2: Photo of the bike next to an 18" Salsa El Mariachi for size comparison.

My first impressions, it's more fun than I possibly imagined!
More importantly, how does it ride (outside of being "fun")?
 

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Holy Moly! I sure hope you have at least an 8" rotor on the front. I suspect that thing could pick up some serious speed going downhill!!!!
 

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Full Tilt Boogie
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1,650 Posts
Discussion Starter · #7 ·
SingingSingleTracker said:
More importantly, how does it ride (outside of being "fun")?
The momentum generated by the wheels is astounding. Once up to speed, it takes no energy at all to keep it moving. It really feels like a 29er on crack. Everying is magnified with the larger wheels. They are heavy but no one who has ridden it yet has even commented on that. On hills it is noticable, though the gearing seems fine in this regard. Coming down hills is awesome! I spun out the big gear, (over 90 inches,) last night in town.

The first thing people say is how surprised by how "normal" it feels. It is stable to a fault, but not hard to corner with at all. It feels much like a motorcycle, where stability in cornering is much higher than that of a bike. It is very confidence insipiring, inspite of the icy roads we have now. With the tires at about 10 psi, I could not make the rear tire slip on clearly icy roads. It's pretty unreal. Curbs are the clearest point of how these things roll over stuff. With lower pressure, the wheels simply pop over them.
 

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Recovering couch patato
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14,017 Posts
Are the airfoil rims too tight or too losse fitting for the Coker tires?

Which tubes are in there, if any?
The 24hr unicycle distance record was set with a tubeless setup.
I've read reports that the Schwalbe 28x2.35" tubes work just fine in 36" unicycle wheels, saves like half a pound per wheel, perhaps?

Will someone ever manage to make one tire out of two? Like joining two really wide 26" tires that clear mud well and roll decently. The frankentire technology (sticking a tread on a shaved bold tire) may also be an option again. We have many 29" options now, so there's less need for frankentires in that size now.
Please report on head tube angle, fork offset and toe clearance?
 

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Full Tilt Boogie
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1,650 Posts
Discussion Starter · #9 ·
The tires we are using are a bastardized Wheels TA slick. This tire is 300 grams lighter than the Coker before cutting the tread, and that drops a further 100 grams off the tire.

The Coker tire REALLY doesn't work with the Aluminum rim anymore. They blow off the rim at any more than 20 psi. It is not an option. The cut slicks do a better job anyway. 29er tubes do work fine. I'm using a standard Bontrager, though I have the rimstrips from Stan to make them tubeless, which we'll be trying wen the weather warms up.


Jan, this thing would be perfect for your beach races. You'd love it.
 

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Recovering couch patato
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No kidding, I SO BADLY want a bike like this, for beach racing as well as other stuff!

Which Stan's strips, custom? Stretching them will narrow them down of course, and may affect stickyness/sealing properties?

How wide are the rims?

Do us a favor and mount a stupidly short gear, and see how steep you can climb with that long-ass chainstays? I bet at 10psi you can ride up steep staircases!

Only real downside I see for larger wheels is that at the lower pressures you'll run, the rims may hit more easily, the volume being bigger to boot.
 

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Full Tilt Boogie
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Discussion Starter · #11 ·
You have to remember that the tires are FOUR PLY!! This changes the PSI scale like you wouldn't believe. The tire are rock hard at 35 psi, and at 10-17 psi they feel pretty normal. With the hub I'm using in the rear, it's hard to get a 34t big ring to work without rubbing the upper der jockey wheel. I'm working on that. The der is simply not designed to move that far down in that short of a space. I had to modify it as well in regards to the low set screw, which would not screww in far enough to stop the der. If a longer screw was used it prevented the der from moving normally to the lower gears. The solution is very simple, but took some time to figure out. I think that combined with the heavier wheels, a gear lower than 22-27 that's on there would be relativly useless. It's simple going to be had to keep the bike going at that low of a speed anyway. That said, with that low of a gear, you could pull stumps!
 

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Recovering couch patato
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You're using a Hope SS hub, I presume? Or Profile 6-speed 150mm?
Yes, it's hard to get a 34t to work then. SRAM is a no-no them, by lack of B-tension spring (if that's how you say that).
Have you considered a longer derailer hanger? With a custom (say) 40t cog (can be had, really), and then like 32-26-22-18-15 you'd still have a great range.

On "my" 36" I'll certainly have wide hubs and the longer derailer hanger I just came up with. Or someone will have to make a longer-body derailer.
 

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Full Tilt Boogie
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1,650 Posts
Discussion Starter · #13 ·
The hubs are 135 front and rear, Surly SS front, Profile 6 spd 135 rear. 150mm makes sense, but hub availability is shoddy at best. I wanted everything on here to be as available as possible. The "simple" solution to the rear der is to have a threaded and tapped "plug" made that would screw into the existing der mount, and move the der out an inch or so. I'm working on that.
 

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Recovering couch patato
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Moving the hanger out an inch will give you 2 x Pi x 2 = over 12t extra clearance if I am not mistaken. On the lower end shifting might hurt a bit, an 11t already feeling like it was placed where a 23t belongs.
Half an inch might do the job if you want to stick to a 34t largest cog?

I have not ridden a 36" more han a couple straights and corners at a bike show, but I think it's not "heavy wheel momentum" keeping you going, but a greatly reduced pulling effect of the uneven terrain on your bike.

4-ply, wow... If those could be ordered in 2-ply, they'd be totally different again I'm sure.
Is rolling resistance over smooth pavement now even a benefit over a fast 26/29" tire?
I can't emphasize enough how much you ROCK daring to do this. You will most certainly not be the last either.

My 36" wishlist :
- V-brakes should do fine
- Really wide hubs, please!
- Long crank compliant (if the wheels are going to fit me, so are the cranks)
- sub-30lbs is possible. With alu frame/fork, pounds lighter still.

Time to come up with a frank/crank design that does away with a bottom bracket. Move the rear wheel as far forward as one wants. :)
 

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OMR - Old Man Riding
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429 Posts
What about....

Using a Rohlof hub? Would this work? (Excuse the ignorance)

Gladshooks!.... that tire is bigger than my inseam :eekster:

We aren't easily impressed here in SoCal but that is an awesome bike! A big fun factor :thumbsup:

OLM...:cool:
SoCal
 

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This place needs an enema
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Nice stuff.

Where'd you source the spokes? Or did you cut 'em yourself from old fenceposts?!!

In case no one else has mentioned it, you *really* need a pic of the bike by itself...

Cheers,

MC
 

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This is just too good to be true!

Please post some extra pics from the bike + frame, willing to share frame drawings? Any commercial plans with this?

Please shoot Mark Slate from WTB an Email about this, also with ride report. I'm talking with him about 31" / 32" mountainbike wheels, but he simply thinks it's not going to work ......
 

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Witty McWitterson
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Sweet!

Can't wait to take some fancy pics of this beast at the open house! I'm all giddy now....
 

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It is all that and more!

I rode that monster Saturday ( I had to leave my first born son as a deposit ;) ) and I must say Ben did a wonderful job of designing this bike. It rides without any unusual quirks at all. For the right application this bike will rock!
Thanks again.
 
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