Vertigo Cycles Fatbike

[smudge]

This is interesting;

Laying down a contiguous "bed" for the actual weld to nest/fuse into. Very interesting. I had never considered this, but it makes perfect sense! As he suggests, even with exceptional miters (which are mandatory for this), you are stealing material from both tubes to create this fusion, and necessarily thinning them at a critical juncture. You can do this with some materials and in certain applications and get away with a fusion weld alone (I do it on stainless intercooler/intake hard pipes), but not in this case. It also occurs to me that this fusion step makes it much easier to get visually stunning (and structurally solid) final welds when it is time to add the filler.

Thanks for letting that little trick slip out!

exactly right on all counts but it also gives the joint some thermal stability when you go back to add filler, all but entirely preventing too big a keyhole opening thanks to too much heat.

if you ever get an opportunity to cut up a bike, take it. Specifically, cut through an acute joint to see if there's a gap underneath the weld bead. Ideally, you won't see any air space at all between the two parent tubes. In a lot of cases though, you'll find that the filler rod "bridges" between them, leaving a triangular gap. With something as notch-sensitive as ti, that's bad news bears.

[MendonCycleSmith]

Thanks for the info Sean, sexy lookin' rig you're building there!

[SmooveP]

Nothing but the finest for this steed:

1. High-rise steel handlebar for strength
2. Post Moderne seatpost 26.6mm (might need a shim for 30.9mm)
3. Adjustable angle stem for easy adjustments in varying terrain
4. Avocet bottle cages, powdercoated pink
5. Scott AT-4 grips (made of real Kraton!)
6. Jandd pink handlebar bag with WOMBATS patch for power pills and energy snacks
7. Avid SD 2.0 cantilever brake levers
8. Gorilla brake booster for awesome skids
9. Cane Creek handlebar end grip extenders for aero tucks
10. Forte Easy Rider saddle in case the 'roids flare up

If Sean doesn't get the cantilever posts on the frame, I'll have to think of something else for #7 and #8.

Haha! Nice! I'm old enough to remember the WOmens' Mountain Biking And Tea Society (WOMBATS). I may have some of that old gear in my box o' parts - probly the pink grips and the SD 2's.

[Peter E]

really like the look of this fatbike. got any numbers of that geo? How short did you manage to get the chain stays?

[jncarpenter]

Smokin'!

WOW! I cannot muster anything more!

[Drevil]

I haven't completely decided on the parts, but I like to tinker. I'll probably start with a Salsa Enabler fork (which fits the A-C of the design), but I'm also in the queue for Lefty clamps. It'll be dressed as a singlespeed or a gearie when the mood strikes.

Since it's getting closer, I figured it was time to start gathering together the parts. Some of it recently purchased, some of it NOS, and some of it being stolen off other bikes:



Have:

• Fat Lefty Clamp (ala Mendon Cyclesmith)
• Tires: Almost all of 'em
• Spokes: double butted silver
• Brake Levers: Paul or Avid Ultimate (haven't decided which to use)
• Saddle: Specialized Phenom or WTB (undecided)
• Grips: Oury (whichever matches the saddle)
• Jones Ti Loop Bar
• Thomson Stem
• Eriksen 450mm 30.9 seatpost
• Speedway Uma 50mm rim for rear
• Avid Full Metal Jacket brake cables
• Paul Shifter Mounts
• Dura Ace Shifters
• XTR Rear Derailleur
• XTR Pedals
• Middleburn 58/94 170mm crank
• PC-951 Chain
• Pink and silver streamers

Haven't yet:

• BB-7 Brakes, 160s both ends
• Phil Wood Ti BB
• Endless Kick-Ass-Cog/ XT Cassette
• Some sort of direct mount front derailleur
• Project 321 Lefty hub
• Surly Large Marge Lite rim
• Silver Reflective tape for rim holes

If I do throw rigid into the mix, I'm thinking of getting a Carver O'Beast. It works with the fat front wheel I already use on my Jones (Paul Whub).

[dRjOn]

i particularly like the tassels...one in either direction?

[Rockin]

I see you are going with the dual-seat option, good choice.

Looking forward to the build-up pics.

[miesj]

nice work!!

[SmooveP]

I see you are going with the dual-seat option, good choice.

Looking forward to the build-up pics.

2 seats, 4 tires and half a fork...

[miesj]

that's a nice list of parts, Jones bar is supersweet!!!
mount a lefty in the frame is awsome, do you have a technical drawing of those clamps for the lefty ??

[elgordo]

2 seats, 4 tires and half a fork...

hilarious

[Drevil]

hilarious

You forgot the prior post. There'll be 3 seats, 2 bars, and 6 brake levers. This thing is gonna be outta control!

[Drevil]

that's a nice list of parts, Jones bar is supersweet!!!
mount a lefty in the frame is awsome, do you have a technical drawing of those clamps for the lefty ??

No sir. Hit up Mendon C to the S for the numbers.

[smudge]

I'm still curious how you're going to keep those tassels attached to your nipples for an entire ride.

[rasse1977]

Different rims front and rear...? Why...?

[Drevil]

Because Lefty is offset, and the Marge Lite has an offset spoke bed, is relatively light, and is available now. Why not the same on the back? Because I bought it a little ways back, plus I already know it works well for me.

[SmooveP]

I'm still curious how you're going to keep those tassels attached to your nipples for an entire ride.

With nipple clamps, of course.
(Sorry, no pics - you'll have to look that up for yourselves.)

[Smallfurry]

Because Lefty is offset, and the Marge Lite has an offset spoke bed, is relatively light, and is available now. Why not the same on the back? Because I bought it a little ways back, plus I already know it works well for me.

I've just put together a lefty wheel with a 80mm GFS, with non-offset drilling. Theres a fair amount of tension on the right side, with a notable amount less on the left side. But IMHO these tensions are fine. With a BFL mounted (at 18 PSI), the disc mounts of the hub, are 1-2 mm from the floor when laid flat. So I'm not sure you actually need an offset rim to make this work. In fact when I get my Lefty, I fully expect to be able to losen the right nips half a turn, while tensioning the left by the same.

Also the project 321 hub is a lovely component. So well made.

[Drevil]

"Direct" from Sean:

A slightly augmented Direct mount standoff

Make it work, then make it pretty.


The standoff wasn't long enough to work with a 100mm shell with a +5mm offset for the rings so...
machined a sleeve to a light press fit, welded around the circumference, turned the weld into a taper, mitered for extra tire clearance, cut a hunk out of a scrap tube, shaped and then fusion welded. Then the weld cap was filed down to make it look as if it were machined from a solid bar.

[rockcrusher]

"Direct" from Sean:

A slightly augmented Direct mount standoff

Make it work, then make it pretty.


The standoff wasn't long enough to work with a 100mm shell with a +5mm offset for the rings so...
machined a sleeve to a light press fit, welded around the circumference, turned the weld into a taper, mitered for extra tire clearance, cut a hunk out of a scrap tube, shaped and then fusion welded. Then the weld cap was filed down to make it look as if it were machined from a solid bar.

Hoe Lee Cow. That is a pretty part. Function over form always works for this architect!

[dRjOn]

i didnt fully clock that you were getting front gearage on this beast til i saw these pics...thats super cool...short fat and shifty!//// impressive space management..!

[Enel]

Subscribed.

Sorry I missed this one for so long. Nice bike Drevil.

[Drevil]

i didnt fully clock that you were getting front gearage on this beast til i saw these pics...thats super cool...short fat and shifty!//// impressive space management..!

After 10 years of almost exclusively riding rigid singlespeeds, I wanted a change. Besides, I have enough fine examples of them.

The sliding drops are insurance, just in case.

[Drevil]