Post your Dirty Jumper

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balooon
balooon's picture

Interested! I'd ride a medium NFE but will reserve judgment pending geo details!

sparksflyhigh wrote:
There were no statistically significant results connecting power output (maximum and average) or heart rate to stiffness, except that the "power quotient", which is the average power/maximum power during a sprint, was higher on the stiffer frame

This is referring to the hypothesis that buttery vibes should smooth out power over the pedalstroke? So per that hypothesis you'd expect a higher 'power quotient' on a buttery frame? Interesting. And you tested that under non-sprint conditions and there wasn't a discernable difference?

holy new page:

sparksflyhigh wrote:

sparksflyhigh wrote:

I tested with a Pioneer crankset power meter, and most runs were on a trainer, so I could compare power in/power out. There were no statistically significant results connecting power output (maximum and average) or heart rate to stiffness, except that the "power quotient", which is the average power/maximum power during a sprint, was higher on the stiffer frame, which is the opposite of Jan's claim. Jan also says that he feels he can do more cardio on a flexy frame, which was not supported by my data. There are all kinds of confounding factors, so I wouldn't go ascribing a performance advantage to stiff frames. Like Jan's test, I only varied the front triangle stiffness, but I used 858 standard, 969 standard, and 858 oversize. Jan's original test with power meter was based on 5 data points, so not exactly the definition of rigorous. My results also didn't support the "stiffer=better power transfer" people, so at least there's that. I'd like to do more research with better equipment and more tightly controlled procedures so I can get more/higher quality data.

Mon, 08/21/2017 - 21:05
Rusty Piton
Rusty Piton's picture

Ryan, you need one of these man. Total spaghettimobile.

emor wrote:
Bicycle commuting is the worst way to get anywhere except for all the other ways.

Mon, 08/21/2017 - 21:53
NOVELTYNAME
NOVELTYNAME's picture

Well shit
Tarck has an actual scientific nerd in the house now

"Folks want options!"

Mon, 08/21/2017 - 22:10
emor
emor's picture

I'm very interested in one of those frames of it fits 650bx50mm

"my main life goal is to have a dirtbag camper van with a bunch of bikes on it, go camping every vacation forever" -- me

Mon, 08/21/2017 - 22:23
jawn doe
jawn doe's picture

well, which one did you keep?
proof of the planing is in the consuming.

Mon, 08/21/2017 - 22:45
sparksflyhigh
sparksflyhigh's picture
(Reply to #46556)

Rusty Piton wrote:
That's awesome. I home you got an A+ on your project!

Thanks, I passed.

Blakey wrote:
This is great!

When will you show Jan your contradictory results?

I already emailed the report to him. No response, lol

emor wrote:
I'm very interested in one of those frames of it fits 650bx50mm

euclid wrote:
Wheel size/tire clearance?

They're designed around 650b, but you could run 26. The S-bend seatstays did not go as planned, so the curve constricts the tire clearance the smaller the wheelsize. They can all fit a 52 THUNDER Burt in the back, but the pokes were cut a bit too short, so they can fit a 48 or 50 mm tire, but only leaves at most a few mm for fenders, dependent on rim. I can get pictures with a Horizon if people are interested. One of the four bikes has a shorter fork than the others, and can't fit a 48. This is the one I'm using on my junk townie.

jawn doe wrote:
well, which one did you keep?
proof of the planing is in the consuming.

I'm using the flexy 858 standard frame, but that's because I have 2 of those, as opposed to 1 of the others. This way I have 1 of each frame spec to get rid of.

balooon wrote:
This is referring to the hypothesis that buttery vibes should smooth out power over the pedalstroke? So per that hypothesis you'd expect a higher 'power quotient' on a buttery frame? Interesting. And you tested that under non-sprint conditions and there wasn't a discernable difference?

The theory proposed by Jan as I understand it is that the buttery vibes improve muscle efficiency and allow a higher level of cardiovascular exertion, whereas with a stiffer frame, the extra resistance will cause the muscles to tap out prematurely, resulting in a lower power quotient. The higher cardiovascular exertion was not evident in my study, as measured by heart rate. I only tested under sprint conditions. Like Jan, I think without a much larger ensemble of data collection gear, there is no reliable way to control the level of exertion, which must be either quantified as an independent/dependent variable or held constant. I would prefer to measure VO2, as well as using a set of strain gauges to construct a more dynamic model of the frame/rider energy system and get a better idea of how the spring of the frame interacts with the rider's biological systems. I need a lot of money for that though

I'll add some more photos of the frames and exact specs in a couple days for those interested.

Tue, 08/22/2017 - 00:46
fixed
fixed's picture

fascinating. can you feel the difference when you ride them on the road? have you ridden them all on the road, or just the trainer?

Tue, 08/22/2017 - 08:17
shane.rrr
shane.rrr's picture

sparksflyhigh, I am very interested in one of these frames. What do i need to do?

Tue, 08/22/2017 - 10:17
sparksflyhigh
sparksflyhigh's picture
(Reply to #46559)

fixed wrote:
fascinating. can you feel the difference when you ride them on the road? have you ridden them all on the road, or just the trainer?

I've only ridden 2 of the frames at length: The stiffest and flexiest ones. They didn't have the same parts on them, so any difference I noticed isn't a worthwhile observation. I don't think I'm a strong enough rider to notice much difference anyway, much less strong than Jan. My strongest test rider, who could consistently hit 750-800 watts during sprints, barely fading even after 16 runs, could feel when he was on the flexy frame.

Shane.rrr, when I post again on the thread with the exact specs. You can message me or whatever if you want to pull the trigger.

Tue, 08/22/2017 - 12:20
shane.rrr
shane.rrr's picture

Sounds like a plan. I'll await on the exact specs. I am 6'2" and ride a 61cm Grando. How small are these frames?

Tue, 08/22/2017 - 12:48
sparksflyhigh
sparksflyhigh's picture

Found the drawing.

385 reach
598 stack
620 front center
440 chainstay
510 actual seat tube
72d Sta
73d hta
67 fork offset
70 mm bb drop
Fillet brazed joints
27.2 seatpost
2x bottle bosses
Standard iso disc tabs
Qr 100/135 spacing
68 bsa threaded bb
Clearance for 50-34 crankset on 45 mm chainline (shimano)
Token needle bearing threadless 9/8 headset
No rear rack bosses
Top tube has cable stops, not guides, meaning that wet brakes would require frame modification or some tape job to route the hoses that way

Tubing specs
Top tube
-25.4 969
-25.4 858
-28.6 858 (like the NFE)
Down tube
-same as above, but add 1/8 inch to diameter
Seat tube
-28.6 9-6 externally butted
Heat tube
-36.0 1.1 wall
Chainstay
-19 mm .9 wall, or 3/4x.035 inch straight gauge, s bend
Seatstay
-12.7 mm .9 wall, or 1/2x.035 inch straight gauge s bend
Dropouts
-Breezer hooded rear, fender eyelet.
Fork
-blades same as old NFE biplane, with extended disc tab
-lightweight Henry James threadless steerer
-brazeons for bottle boss on side, as well as fender, low-rider rack, and platform rack in Haulin colin/nitto spec

Color is RAL 5011 steel blue powder coat

Caveats: I used a tight radius bender to make the s bends, there are some small ripples on the inside of the bends. A cosmetic issue
The powder coat is not professional, I did it personally, each frame has some blemishes/orange peel, etc
Fork tire clearance is significantly more than crown vertically, there is for more room for fenders in the back
These were the last frames I build before I got a real jig. Alignment is not perfect, you may have to pull the rim a mm or two to center it in the frame/fork before closing the qr. Likewise, the s bend stays are not completely in phase when seen from the side-cosmetic issue
Dents for chainrings are ugly, were made ex post facto hastily, resulting in some paint chips, etc
In my hurry to get them done, bottle bosses were accidentally installed at 68mm, rather than the 63.5 spec. You will need either bottle bosses with extraordinarily long slots, or you'll need to file/drill some cages to get them to fit. I was quite annoyed with myself when I discovered this issue.
One of the frames has a third threaded boss near one of the bottle bosses: Another manufacturing error.
The blades have a reputation for failure by cracking at the top of the extended disc tab when used by Elephant. Ride at your own risk and keep an eye on the fork.
That's all the relevant info I believe

Photos soon

Tue, 08/22/2017 - 14:33
sparksflyhigh
sparksflyhigh's picture

Tire shown is WTB Horizon. Also, frame have downtube shifter bosses. BB not inluded, unless you want a barely used RS500, in which case, add $10












Tue, 08/22/2017 - 14:57
shane.rrr
shane.rrr's picture

I'd like to jump on one of these frames but looking at the numbers it looks like they might be a little small for me

Tue, 08/22/2017 - 15:42
sparksflyhigh
sparksflyhigh's picture

Yeah I had it backwards, the reach is similar to a medium nfe, but the stack is a bit closer to the large nfe. But the slacker Sta makes the top tube longer than the reach would indicate

Tue, 08/22/2017 - 16:20
mdilthey
mdilthey's picture
(Reply to #46565)

sparksflyhigh wrote:
iwillbe wrote:
sparksflyhigh wrote:
Cost of materials: $200 shipped

would one of them fit someone who's 6'6" and likes a pretty long position on the bike?

Ehhhh probably not. I can answer you with numbers when I find the drawing. At my height, it feels right but you would need an extra long stem and a lot of seatpost and it might be counterproductive.

How about 6'1" with a short torso and souper long legs? Wicked project, by the way.

26/M/41t N/W

Tue, 08/22/2017 - 17:15
sparksflyhigh
sparksflyhigh's picture

I've got a 34" inseam, and the frames work well for me with a lot of post showing. The numbers are upthread but I think you'd be fine unless your proportions are truly freakish

Tue, 08/22/2017 - 17:48
Whippin Skidz
Whippin Skidz's picture

Uh, kinda want one for real but to be honest I have no idea what those number mean

Tue, 08/22/2017 - 18:02
sparksflyhigh
sparksflyhigh's picture

It fits like a 56 road bike, if that makes sense

Tue, 08/22/2017 - 18:15
Whippin Skidz
Whippin Skidz's picture

Shit now I really want one. But I never ride bikes so it'd be pointless.

Tue, 08/22/2017 - 18:58
spaghetti
spaghetti's picture

it's very very upsetting that this would fit me perfectly

Tue, 08/22/2017 - 19:05
Tail Hook Lengthener
Tail Hook Lengthener's picture

What did Tarck do to deserve such a high quality FNG?

Sneaky Viking wrote:
when you look back at your life sometimes you see a set of hands on your keyboard and a set of paws, but sometimes there's only a set of paws and that's when Tarckbear was typing for you.

Tue, 08/22/2017 - 21:40
jawn doe
jawn doe's picture

PM'd WRT my ruined day

Tue, 08/22/2017 - 22:36
Rusty Piton
Rusty Piton's picture
(Reply to #46573)

spaghetti wrote:
it's very very upsetting that this would fit me perfectly

It's a sign dude!

emor wrote:
Bicycle commuting is the worst way to get anywhere except for all the other ways.

Tue, 08/22/2017 - 22:48
Blakey
Blakey's picture
(Reply to #46574)

Wintage Townie wrote:
What did Tarck do to deserve such a high quality FNG?

for every red ano dirty floor day ruiner you get a planing professor

Tue, 08/22/2017 - 22:53
emor
emor's picture

So, so tempted

But I think a 56 is too small for how I'd roll this bike

I have no idea what the reach/stack on the nordavinden is -- Sean didn't provide that info -- and I have no idea how to measure them myself.

"my main life goal is to have a dirtbag camper van with a bunch of bikes on it, go camping every vacation forever" -- me

Tue, 08/22/2017 - 23:57
chazzwazzer
chazzwazzer's picture

Doug, if the Norda fork length is 380 like I think I remember it is, and your frame is a 58, based on the Rawland geo chart (and assuming a general headset) you've got approx 397 reach and 581 stack.

Wed, 08/23/2017 - 03:33
jawn doe
jawn doe's picture

dug- put yer bike's rear wheel against a vertical datum (walls aren't really plumb but probably close enough to party) and measure!
ground to ht minus ground to bb = stack
wall to ht minus wall to bb = reach

Wed, 08/23/2017 - 07:59
eric_ssucks
eric_ssucks's picture

Doug, I'll betcha that one of these bikes is close enough that it will fit you fine.

Wed, 08/23/2017 - 11:49
sparksflyhigh
sparksflyhigh's picture
(Reply to #46579)

spaghetti wrote:
it's very very upsetting that this would fit me perfectly

Whippin Skidz wrote:
Shit now I really want one. But I never ride bikes so it'd be pointless.

Shoot me a PM if you're interested or want to know more

Wed, 08/23/2017 - 11:58
spaghetti
spaghetti's picture

very much want it but i'm out. financially makes no sense right now.
passing along to another tarcker

Wed, 08/23/2017 - 17:33
Whippin Skidz
Whippin Skidz's picture

edit: I'll pass. I should put the money into paying off debt and just ride the bikes I have more.

Wed, 08/23/2017 - 18:22
NOVELTYNAME
NOVELTYNAME's picture

You guys are turning into serotta forums
If it were only one cm smaller
If I hadn't just bought another frame
GLWS!

"Folks want options!"

Wed, 08/23/2017 - 21:08
Whippin Skidz
Whippin Skidz's picture

I want it. But I shouldn't buy it. I gotta be, like, an adult or something right now.

Wed, 08/23/2017 - 21:34
Goddamnit Gunther
Goddamnit Gunther's picture
(Reply to #46584)

Whippin Skidz wrote:
I want it. But I shouldn't buy it. I gotta be, like, an adult or something right now.

Endpoint wrote:
turdly buttways

Wed, 08/23/2017 - 21:41
Rusty Piton
Rusty Piton's picture

You're all making the wrong decision.

emor wrote:
Bicycle commuting is the worst way to get anywhere except for all the other ways.

Wed, 08/23/2017 - 23:02
mdilthey
mdilthey's picture
(Reply to #46586)

Blakey wrote:
Wintage Townie wrote:
What did Tarck do to deserve such a high quality FNG?

for every red ano dirty floor day ruiner you get a planing professor

26/M/41t N/W

Thu, 08/24/2017 - 04:22
hiimjoshimabike
hiimjoshimabike's picture

Finally got a decent glamour shot of my H/G:

Just ride your fucking bike and don't be a dick about it.

Thu, 08/24/2017 - 09:59
Tail Hook Lengthener
Tail Hook Lengthener's picture

Yes.

Sneaky Viking wrote:
when you look back at your life sometimes you see a set of hands on your keyboard and a set of paws, but sometimes there's only a set of paws and that's when Tarckbear was typing for you.

Thu, 08/24/2017 - 10:25
Rusty Piton
Rusty Piton's picture

Hell yes.

emor wrote:
Bicycle commuting is the worst way to get anywhere except for all the other ways.

Thu, 08/24/2017 - 10:34
kmcdon
kmcdon's picture


Put new shoes on the cross-check. Considering that my wheelbuilder's straggler has horizons on it, and they're within 2mm of rubbing the chainstays, I'm really, really happy about this. I do need to re-seat the bead on these though, because drunken me couldn't get them on straight at 11pm last night. I figure once they've spent a day inflated it should be easier, that was the case with the hetres that used to be on here.

Can't. Wait. For. Tubeless.

Thu, 08/24/2017 - 10:59
JUGE FREDD
JUGE FREDD's picture
(Reply to #46591)

hiimjoshimabike wrote:
Finally got a decent glamour shot of my H/G:

have you tried the front kickstand I gave you yet?

It's a struggle, but you cut out his tongue, and his last words are "atmo atmo Atmo ATMO ATMOOOOOGORIHGGHRSHGGRLMGGMMGMgrrglegurglegrr....."
– akasnowmaaan

Thu, 08/24/2017 - 14:09
hiljentaa
hiljentaa's picture
(Reply to #46592)

hiimjoshimabike wrote:
Finally got a decent glamour shot of my H/G:

Proper af

Thu, 08/24/2017 - 14:29
schultzor
schultzor's picture
(Reply to #46593)

hiimjoshimabike wrote:
Finally got a decent glamour shot of my H/G:

smiley
Tubus lowriders in the front?

Thu, 08/24/2017 - 14:35
hiimjoshimabike
hiimjoshimabike's picture
(Reply to #46594)

schultzor wrote:
Tubus lowriders in the front?

Yep. Tubus Duo. Works gud. My only problem is the two parallel tubs that hug the fork legs are spaced about 2mm wider than the legs, so they like to loosen the braze-on bolts smiley

JUGE FREDD wrote:
have you tried the front kickstand I gave you yet?

Yeah, but it's pretty unstable. It seems to have been designed to stabilize the front end when a rear KS is used, rather than on its own. ¯\_(ツ)_/¯

Just ride your fucking bike and don't be a dick about it.

Thu, 08/24/2017 - 15:11
Face
Face's picture

2mm washers?

Mr. Pubes wrote:
i fear that you are so lost in your own asshole that you may never be found again. do you have a flare gun? send for help.

Thu, 08/24/2017 - 16:04
JUGE FREDD
JUGE FREDD's picture

eh just cold-set the rack

and use some blue loctite

on most forks there's a 1cm+ gap and you gotta use annoying spacers

It's a struggle, but you cut out his tongue, and his last words are "atmo atmo Atmo ATMO ATMOOOOOGORIHGGHRSHGGRLMGGMMGMgrrglegurglegrr....."
– akasnowmaaan

Thu, 08/24/2017 - 18:14
mdilthey
mdilthey's picture

That bike is phenomenal, love the stem bag. And the wall.

26/M/41t N/W

Thu, 08/24/2017 - 20:02
Andrew_Squirrel
Andrew_Squirrel's picture
(Reply to #46598)

JUGE FREDD wrote:
eh just cold-set the rack

and use some blue loctite

on most forks there's a 1cm+ gap and you gotta use annoying spacers

I had to use a total of 6 spacers for the Duo on the Elephant.
4 on the mid fork barrel (one on each side), 2 at the drop out.
Tubus included 4 spacers and I used 2 slightly smaller spacers from my hardware bin.
I didn't realize you could cold set this rack.

Thu, 08/24/2017 - 20:27
hiimjoshimabike
hiimjoshimabike's picture

Thanks for the advice, Fred!

Thanks for the compliments, everyone!

@sparksflyhigh, I'll dibs one if not already spoken for!

Just ride your fucking bike and don't be a dick about it.

Thu, 08/24/2017 - 20:34
shane.rrr
shane.rrr's picture
(Reply to #46600)

kmcdon wrote:

Put new shoes on the cross-check. Considering that my wheelbuilder's straggler has horizons on it, and they're within 2mm of rubbing the chainstays, I'm really, really happy about this. I do need to re-seat the bead on these though, because drunken me couldn't get them on straight at 11pm last night. I figure once they've spent a day inflated it should be easier, that was the case with the hetres that used to be on here.

Can't. Wait. For. Tubeless.

I have those same tires tubeless on my grando. Get to it already! its worth it

Fri, 08/25/2017 - 11:47

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