kraffft work

[kraffft]

Here's that road bike again..



Set up for a mile trial with two of the 76mm Flywheels that I've gotten my fastest skate times with.

Normal road bike time was: 3:01.44
Road bike with skate front wheels: 3:04.78

Considering I had to slow down more than usual for the rotary u-turn at the half mile, the bike wheel and the flywheels are almost exactly as fast!

Now the question is.. If I get a 3 minute mile on a lean/steer device, where only my feet touch the device, and only human power is used for propulsion.. is that a 3 minute skate mile?

[sk8norcal]

^^ nice! how does the front end feel?

i am doing some mod on my Quadcarver, the front end just feels so jittery..(should have some RTC..)

check this one from my tilting vehicle blog,
Tilting Vehicles Blog: mtb fork tilt

want to try this thing,
wackyboards: StreetSurfer

[engebo_kelsey]

I bet there's some group somewhere that's dedicated to building all of Da Vinci's sketches.

i seem to recall seeing an ad for a tv show on the discovery channel about guys that did that. looked pretty cool, but never got around to watching it

[sk8norcal]

kraffft, u mentioned

various other hybrids (are any of them as fast/easy to push as a longboard?)

a snakeboard will beat a skateboard in a sprint from stand start (if the rule allows no pushing...)

-wearing a full fairing

seen this? now try it with a board...
follow link, they claim very high speed..
http://wackyboards.blogspot.com/2009...e-sailing.html

or this for downhill
OhGizmo! Archive SpeedSkiing With “Emma”, At 250kph


Couple more ideas,
a skateboard combined with a Kick'nGo
wackyboards: Pulse KickN'Go

a skateboarding using one telemark x-cross country skate...
or a shoe with two side wheels using a 1 way clutch mechanism
Nordic Skater: Cross-Country Skis, Ice Skates, Inline Skates, Roller Skis

seen this?
wackyboards: Rockit

last idea,
tandem skateboarding on the x-cat
wackyboards: X-Cat

[kraffft]

how about UHMW coated wheelwells? wheelbite is essentially due to the friction between the wheel and the wooden deck. reduce friction... reduce chances of wheelbite?

I like Barf's sliptape tip on this one.. hard to beat. That's another plus of the UHMW wheels though.. they don't get much wheelbite at all.. If you wanted to get absurd, you could have a disc of UHMW on the outside face of your wheel that wouldn't touch the ground, but would be the first thing the deck rubbed against in a wheelbite situation.

i seem to recall seeing an ad for a tv show on the discovery channel about guys that did that. looked pretty cool, but never got around to watching it

Leonardo's Dream Machines it turns out to be called.. PBS documentary 2005.. they tried to build an 80 foot crossbow that fired cannonballs, and a hang glider, out of period accurate materials.. Looks like there's plenty of other better sources of info on Leonardo's inventions though.

i got a 'kraffft' section on my wackyboard page now...

First off, I gotta say it's a real pleasure to have you joining the conversation here Hung Chang.. And I'm certainly proud of the dubious honor of being included on the wackyboard blog. I've been putting off giving your site a thorough look-through for a while now.. (as well as the various ABEC 11/Chaput threads).. Seriously overwhelming amount of ideas and jumping off points.

One of these days I'll make a board for ya that's sole purpose is to be as wacky as possible (let me know if you have any requests).. but something that seems like it might not be obvious to everyone is that almost all the boards I've made and experiments I've done have had some fairly logical/useful intention behind them.. Maybe that's the soul of true wackiness though.. The inventor has to be naive to it.

Anyway.. apologies to all of y'all that don't have the attention span for the text heavy action.. I'm just gonna dive in here..

there were many giant lappers in the 70's..

Love that old graphic design.. and funny to see how similar that product was.. I was even thinking about a similar price tag! (though the shipping would have to be adjusted for 2009 dollars).

(bike with skate front wheels)^^ nice! how does the front end feel?

The bike was solely set up for the mile test (took about an hour to build).. The only reason I put two wheels on it (instead of one) was so it would be a more accurate speed comparison.

But the front end feels terrible. It would need a lot of tweaking to start to be even reasonably nice to ride.

a snakeboard will beat a skateboard in a sprint from stand start (if the rule allows no pushing...)

I'm going to take that as a no.. there are no hybrids that are faster than a longboard on level ground!?

seen this? now try it with a board... (ice skate sailing)
or this for downhill (Emma speed skiing fairing)

It's gonna happen.. probably cardboard fiber instead of carbon fiber though.

a skateboard combined with a Kick'nGo

That's what I'm working on right now.. I don't have a Kick'nGo rear end lying around.. so I'm scrapping it together out of bike parts. It's one of the more challenging and nebulous design problems I've undertaken.. so many ways it could be done. Keeping it quick, simple, and dirty as usual. Here's the back wheel:



6in/150mm urethane wheel with single speed freewheel bicycle hub. I cut the wheel in half radially to get it around the hub.

a skateboarding using one telemark x-cross country skate...
or a shoe with two side wheels using a 1 way clutch mechanism

I'm guessing the level ground top speeds of those two things used as intended are around the same as a longboard (slower than rollerblades).

I like the mechanisms though.. they just need to be geared up somehow..

seen this? Rockit

That's the most depressing thing I've seen all week.

tandem skateboarding on the x-cat

Looks like there's no drafting aerodynamic advantage with that design.. but it's all cuddly!

[Marleyfan1101]

kraffft, u mentioned

last idea,
tandem skateboarding on the x-cat
wackyboards: X-Cat

that's actually quite easy to do with regular boards, it just takes coordination. if you try it, make one person the leader that decides the turning.

[sk8norcal]

I'm going to take that as a no.. there are no hybrids that are faster than a longboard on level ground!?

the dirt surfer could be faster with quality high pressure wheels, especially on rough roads.

the skatebike could be faster also...

the rollsrolls come with big 150mm scooter wheels. I test rode one before, very fast...

[sk8norcal]

[sk8norcal]

that's actually quite easy to do with regular boards, it just takes coordination. if you try it, make one person the leader that decides the turning.

I am talking about standing up...
it would be interesting if the boards are connected..


two person on one board...
wackyboards: Tandem Snowboard

[speshlspeclsteak]

I am talking about standing up...
it would be interesting if the boards are connected..


two person on one board...
wackyboards: Tandem Snowboard

makes me to find the footage of the pair of skis me and some co workers found in the junk rental bin that had 3 sets of bindings on each

[dunnersboarder]

[kraffft]

the dirt surfer could be faster with quality high pressure wheels, especially on rough roads.

the skatebike could be faster also...

the rollsrolls come with big 150mm scooter wheels. I test rode one before, very fast...

I would grant that if you changed the gearing on the skatebike that it would be faster. But it's more of a unicycle with training wheels than a skateboard..

The dirt surfer and the rolls both have the limitation of how fast you can push them..

My understanding of flat land top speed is that any device that you push like a skateboard is going to be limited by how fast you can move your leg. Your foot has to make stationary contact with the ground in order to exert force.

With rollerblades, ice skates, and pumping on a skateboard, you can still add speed once you've passed the speed limit of pushing because you're feet can exert force against the ground while they're moving forward. Those methods have a limit as well.. but it's even trickier to explain than pushing..

Then bicycling and anything else utilizing mechanical systems to convert the relatively slow, high torque motions the human body is best at, into fast, low torque motions, has essentially no bodily limitation. You're only limited by friction.

The issue of how rough the surface is is very significant.. A shortboard with 40mm 98a wheels is as fast as a longboard if you're racing on perfectly smooth concrete. In these tests, I'm interested in average to rough pavement. High quality longboard wheels seem to be the bare minimum to get ideal results from any propulsion method on that surface. Larger wheels will be faster (and safer) on rougher terrain, won't rely on high quality bearings as much, and can be more efficient (longer coasting time).. But those factors are negligible compared the difference in ride quality that top speed reflects.

That's a very arbitrary value "ride quality".. but that's what I'm ultimately interested in..

[sk8norcal]

^kraffft, completely agree...
pushing become less and less efficient as speed climbs, its like being stuck in a low gear on a bike...
a reworked 'longbow' might be more efficient,
http://wackyboards.blogspot.com/sear...7;20and%20down
also, parallel stance would ideally be more efficient since it evens up the usage of muscle, but its hard to ride parallel..

makes me to find the footage of the pair of skis me and some co workers found in the junk rental bin that had 3 sets of bindings on each

I luv utube...

YouTube - tandem skiing

YouTube- The Tandem Ski

YouTube- TANDEM TELE!!!

http://wackyboards.blogspot.com/2009...ndem-luge.html
tandem speedboarding anyone?

[sk8norcal]

how the hell do these guys slow down? i doubt u could do s slide type thing like skiing and u cudnt do a pizza thing cause the wheels aint gonna slide!

from what i read,

they use a drag brake for going downhill.

they try to use slow wheels, to add resistence for training,

looks like a good full body workout...

[Chainmaillekid]

i got a 'kraffft' section on my wackyboard page now...

wackyboards: }kraffft

Thats your page? O.o

Do you know how many times we went there when we started development on our trucks? XD

It was a lot.

[sk8norcal]

Thats your page? O.o

Do you know how many times we went there when we started development on our trucks? XD

It was a lot.

haha, glad u like it...

i just made that fairly recently...
it was to replace the original one
www.geocities.com/wackyboards
(no longer there since yahoo ended their geocities service)

I started that page back in 2002....

I gonna start another blog "skateporn"
for all the 'traditional' skateboard stuff....
a compilation of all unusual skate trucks/decks/wheels....
your truck will definitely be in there...

[kraffft]

This is another use for UHMW wheels.. Screw a slide puck to one side and you have a nice hand held puck..

I recommend wearing gloves while you get used to using these.. and I wouldn't use them without gloves while learning a slide.. but they're pretty nice..

It's a different feel than slide gloves.. much more direct control over the angle the puck touches the ground at.. and less sweaty.

YouTube - handheld wheel pucks 11/11/09

(apologies for the insane camera work on this one)

One little refinement makes them clip to your pocket/belt/etc:



and if you countersink the fasteners you can use either side to slide on. Wheel side down gives you more control over the puck contact. Puck side down is more stable.

[sk8norcal]

nice! they remind me of air hockey paddles..



btw, Brad Edward also uses a hand held puck...
check the latest slide fest vid..

[Chainmaillekid]

You're getting close to the same territory as Riley's current Pet project ( which he has had no time for )

He explained to to me... breifly.

The Idea was to use something like That incorperated into a slide glove.
Sliding palms down means your head is also down.

But if you can turn the hand so that its facing downhill as you slide, You'll be better able to see.

[engebo_kelsey]

so, strange idea popped into my head. doubtful it would work unfortunately, but definitely worth putting out there. a shoe with UHMW (or some other slide material) soles or clamp-on type soles for foot breaking. trouble would arise in pushing and being uneven, with the other shoe while riding and such.