Gcrank's 'Flat Out Racing-Gravity Works For Me'

[gcrank1]

Here's the go to that got me all revved about these:
viewtopic.php?f=43&t=41784&st=0&sk=t&sd=a&start=165

[gcrank1]

Geesh.....these things are addictive too!
Morph had a flat front tire today.......and I had a nice, long, new hill to try within 6 mi. of home on a lightly traveled town road. No new/spare tube in the place or even a patch kit......
So I pulled out G-Bike No,2; a Huffy Cranbrook that still has the crank (so I can pedal UP the hill, too?), roadbike dropbars and a setback & slammed banana seat. It is surprisingly comfortable. But the best part is the Bontrager H-2 high pressure tires, these at 80psi, and they FLY. I talked my wife (somehow I think she has only reluctantly subscribed to this new passion) into pacing me on run two, and she says it looked like I got just shy of 45mph.
Hey, ya'll, this is about as easy as it gets to get into G-Bikin' !!! I know it doesnt meet the 'sanctioned' rules (20" or less wheels, 50" max wheelbase, 75#), but there aint no sanctioned race here!
Im gettin' that flat fixed and running Morph asap to see how it compares. If I can talk a bud into it I may even get a S x S run........ .

[gcrank1]

3 pm ish today, ran Morph with the new tube down that big (.5 mi. drop) hill and my wife says it was an honest 45mph plus, maybe pushing the 47.5ish mark. Bike ran super, nice and stable, and the weight under me definitely feels more substantial at speed than the Huffy. I can see that breaking the 50mph mark is going to take some work, or BIGGER hills!

[kingfish254]

GC, did you ever see the photo of one of the early mock ups of Fugsley? I bet a Dahon would make a decent platform for a gravity bike.

[gcrank1]

I can see potential there, but since BMX, and other more available platforms are so cheap and readily available, it might be better used more as intended? (but then whats the fun of that?). My practical side always argues with my 'dark' side........
After watching some of those Aussie videos I cant believe how low those riders get! For me I cant get my butt too low or I cant bend my knees back to pegs without cramps, and/or my knees too close to the ground, and then if Im stretched out too long I have to support too much weight with my arms (no chest-rest pad) and I cant crank my head back far enough to see; lots of issues to get a reasonably comfortable fit for a long run.
I think if one ignores the wheelbase 50" 'sanctioned' rule and makes a long frame with a high enough toptube to put a chest-rest on that you might have a goer (but Im a new study at this), more of a drag-bike look? I see FastEddie has quite the 'chair' on one of his, and I see the sense in it now. Rules?, what for?, lets build RRB G-Racers!
You build that Dahon, K-Fish, and see if you can beat my 45mph (so far, but goin' for mo )........
PS: Im thinkin' that for safety Im going to mount an LED front flasher and maybe get a marine can powered fog horn, or such, if I can figure a way to activate from the bars. It might just get somebodies attention that otherwise wont really see a G-Bike coming.

[MplsCoaster]

Cool to see your hitting some high speeds! Congrats!

[DesignIt]

Looks like fun! I think the 50MPH barrier is about to come down.

I wonder what the biggest hill in the Houston area is?

[gcrank1]

I just didnt like the MkII version bar setup.....so I went with a cutdown 'moon' bar for a simple arc with the ends dropped almost straight down (a Fast Eddie kinda bar ) on an inverted 4.5" stem.
I dont know if my old, bad knees can take kneelers.......
Update: I couldnt stand the suspense; I slammed the original OCC saddle and with the rearsets I can stretch out on the toptube; my knees run about even with the bottom tube; it looks and feels like a go.......

Morph, MkIII

[gcrank1]

Finally got another couple of runs in on different hills. I thought I could get more out of the new one than the 35.....
Went back to the last hill and ran another 45mph (paced by pickup) and it felt sweet; Morph and I are ready to go take on a new monster hill on my list.
Strange, but my wife asked about my Life Insurance and said she wont go to the new hill with me...........something about me lookin' too scary....but hey, Halloween is coming!

[iven]

I just didnt like the MkII version bar setup.....so I went with a cutdown 'moon' bar for a simple arc with the ends dropped almost straight down (a Fast Eddie kinda bar ) on an inverted 4.5" stem.
I dont know if my old, bad knees can take kneelers.......
Update: I couldnt stand the suspense; I slammed the original OCC saddle and with the rearsets I can stretch out on the toptube; my knees run about even with the bottom tube; it looks and feels like a go.......

Morph, MkIII

what size fork is that?
i never thought a normal fork could work on a stingray occ without a 24 to 26 front wheel

[gcrank1]

I believe it is a cheap MTB fork (decal says 'MoZo) for a 26". It goes 10" from the axle center to the brake arm stud, but I have no brakes (and really would like to have some up there) to see just where the pad would end up on a rim to know for sure. Of course, a 20" wheel/hub/axle bolts right in. I did not what to use the offset for rake stock front end for higher than bicycle speeds.

[iven]

it kinda funny..
i saw this creation, shortly after this was posted on a cl..
http://redding.craigslist.org/bik/3179533126.html

and for brakes, have you thought about disc brake adapters like this?
http://www.bombhillsspeedkills.com/2009/10/broakland-6-bolt-iso-adapter.html#.UETn7rJlQfw
you could use a rear wheel in front with one for a front brake..
also you could even put one in the rear and use one of those double pull levers for the v-brakes and disc

[gcrank1]

Well, Ivan, you know you can get at least 45mph out of one...........we could have our own 'class', Downhill Choppers
Thanx for that ISO adapter link, I had not been aware of them. If the big V-brake on the back didnt work so well I would think about putting a disc back there and with a replacement narrow rear wheel might be just the thing for an ISO male hub. I dont think any rearhub located to front would work to disc it, I cant spread those fork legs.