Cycling and bicycle discussion forums. 
   Click here to join our community Log in to access your Control Panel  


Go Back   > >

Alt Bike Culture Chopped, dropped, stretched, lifted, and otherwise cut up and put back together. The art and science of choppers, cruisers, lowriders and the vast world of mutant bicycles.

User Tag List

Reply
 
Thread Tools Search this Thread
Old 10-09-05, 09:08 PM   #1
highspeedcycle
Senior Member
Thread Starter
 
Join Date: Apr 2005
Bikes:
Posts: 145
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Drag bike

I was just thinking, what could I do to convert a wal-mart mtn bike into a bike to be used to go from 0-20mph really fast. lol i know it sounds stupid but i wanna try to do it.

What should i add/remove? I know the front gears and deraillaur(spell check) lol

What kinda tires and wheels?

anything else?

thanks
http://www.NickReynolds.net
highspeedcycle is offline   Reply With Quote
Old 10-09-05, 10:29 PM   #2
Brian
Senior Member
 
Brian's Avatar
 
Join Date: Nov 2004
Location: Between the mountains and the lake.
Bikes: 8 bikes - one for each day of the week!
Posts: 16,683
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Depends on how strong your legs are, and how fast you want to spin. Someone should come to your rescue with the math for the gearing. In the meantime, you will want to remove an excess weight.

It is not our place to ask why, only to help you achieve your goal, as dubious as it may seem.
Brian is offline   Reply With Quote
Old 10-10-05, 05:37 AM   #3
Stacey
Non Tribuo Anus Rodentum and off to the next adventure (RIP)
 
Stacey's Avatar
 
Join Date: Dec 2002
Bikes:
Posts: 9,161
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
You might want to look in to energy storing mass such as a flywheel. Spin the flywheel up, engage the rear dirve and off you go.


Don't forget to hang on!
__________________
Stacey is offline   Reply With Quote
Old 10-10-05, 09:02 AM   #4
Rincewind8
Radfahrer
 
Rincewind8's Avatar
 
Join Date: Mar 2004
Bikes:
Posts: 656
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Quote:
Originally Posted by highspeedcycle
I was just thinking, what could I do to convert a wal-mart mtn bike into a bike to be used to go from 0-20mph really fast. lol i know it sounds stupid but i wanna try to do it.

What should i add/remove? I know the front gears and deraillaur(spell check) lol

What kinda tires and wheels?

anything else?

thanks
http://www.NickReynolds.net
I don't know what exactly you want to do. Do you want to just want to go from 0-20mph and then stop or do you want to keep going at 20mph. What kind of surface are you planning to do that on, closed parking lot with smooth pavement or bike trail or...? In general, to make a bike accelerate fast, get fairly narrow high pressure tires and small diameter wheels. Possibly just one gear and possibly the gear range, so that you just not spin out at the highest speed you want to reach. There is a pretty good gear calculator here:
http://sheldonbrown.com/gears/
__________________
TH 1.81 (133kg*62)
Rincewind8 is offline   Reply With Quote
Old 10-10-05, 10:49 AM   #5
Sir Lunch-a-lot
Senior Member
 
Sir Lunch-a-lot's Avatar
 
Join Date: Jun 2005
Location: Saskatchewan
Bikes: Customized Sekine
Posts: 377
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 4 Post(s)
Maybe add on some sort of a fairing to cut down on wind resistance.
Sir Lunch-a-lot is offline   Reply With Quote
Old 10-10-05, 01:38 PM   #6
wearyourtruth
Ride for Life
 
wearyourtruth's Avatar
 
Join Date: Jun 2004
Location: Baltimore
Bikes:
Posts: 2,729
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
find a steep hill
wearyourtruth is offline   Reply With Quote
Old 10-10-05, 08:01 PM   #7
jeff-o
Recumbent Evangelist
 
Join Date: Mar 2005
Location: Kitchener, Ontario
Bikes: Rebel Cycles Trike, Trek 7500FX
Posts: 2,991
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
get two very large, industrial-sized elastic bands......
jeff-o is offline   Reply With Quote
Old 10-11-05, 12:07 AM   #8
biodiesel
Senior Member
 
biodiesel's Avatar
 
Join Date: Apr 2005
Bikes:
Posts: 543
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
You need one of these.

An xtracycle without racks. You can't possibly wheelie this thing and will almost never endo. On a rig like this you look like a drag racer. Then you just need a can of NOS.
biodiesel is offline   Reply With Quote
Old 10-11-05, 02:07 AM   #9
Eatadonut
You know you want to.
 
Eatadonut's Avatar
 
Join Date: Jun 2005
Location: Norman, Oklahoma
Bikes: Pinarello Prince, 1980's 531 steel fixie commuter, FrankenMTB
Posts: 1,896
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
for the gearing, I would use probably a 34-25. That's the granny gear on my roadie, and if I remember correctly it gets to 20.4 mph at about 150 rpm, and I can spin it up pretty quickly.

I'm liking the flywheel idea. How do you rig up a clutch for your bike, though? Think about the usefulness in traffic situations. No more angry drivers when a red light goes green and you're working to get to speed.
__________________
Weather today: Hot. Humid. Potholes.
Eatadonut is offline   Reply With Quote
Old 10-12-05, 10:41 PM   #10
highspeedcycle
Senior Member
Thread Starter
 
Join Date: Apr 2005
Bikes:
Posts: 145
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
FLYWHEEL, omg, why did i not think of that. i love it.

Lets work on this now!... What parts should i start with and whats the basic design, i love it.

thanks
Nick
highspeedcycle is offline   Reply With Quote
Old 10-13-05, 07:22 AM   #11
Stacey
Non Tribuo Anus Rodentum and off to the next adventure (RIP)
 
Stacey's Avatar
 
Join Date: Dec 2002
Bikes:
Posts: 9,161
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Gee, all I have is concept, and that's free. You want design? That's $250 an hour

Seriously. I'm thinking of the flywheel from an old Schwinn Excersize bike. Drive it from one of the sprockets on one of those old Front Feewheel systems Schwinn used on their gaspipe lightweights. Use the other sprocket to drive the rear wheel. With the bike up on a drop stand (back wheel up while you get the mass up to speed)you crank the snot out of it, the ffs will let the rotational mass spin without the cranks beating the crap out of your legs. Just a starting point.
__________________
Stacey is offline   Reply With Quote
Old 10-13-05, 02:59 PM   #12
Brian
Senior Member
 
Brian's Avatar
 
Join Date: Nov 2004
Location: Between the mountains and the lake.
Bikes: 8 bikes - one for each day of the week!
Posts: 16,683
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Flywheel? Chainguard. When that chain snaps, it's going to be dangerous.
Brian is offline   Reply With Quote
Old 10-13-05, 07:38 PM   #13
Eatadonut
You know you want to.
 
Eatadonut's Avatar
 
Join Date: Jun 2005
Location: Norman, Oklahoma
Bikes: Pinarello Prince, 1980's 531 steel fixie commuter, FrankenMTB
Posts: 1,896
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
why would the chain be any more likely to snap than a normal chain, also, why would it be more dangerous?
__________________
Weather today: Hot. Humid. Potholes.
Eatadonut is offline   Reply With Quote
Old 10-13-05, 07:43 PM   #14
Brian
Senior Member
 
Brian's Avatar
 
Join Date: Nov 2004
Location: Between the mountains and the lake.
Bikes: 8 bikes - one for each day of the week!
Posts: 16,683
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
With a flywheel? Stored energy + bike chain = accident.
Brian is offline   Reply With Quote
Old 10-13-05, 07:55 PM   #15
Eatadonut
You know you want to.
 
Eatadonut's Avatar
 
Join Date: Jun 2005
Location: Norman, Oklahoma
Bikes: Pinarello Prince, 1980's 531 steel fixie commuter, FrankenMTB
Posts: 1,896
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
...much like dropping the clutch at 8k rpm in a truck. I gotcha. That's why you gotta keep the chain spinning as you release the clutch.

Also, remember that there's no way you'll be applying more force to the chain this way than a fixie would skidding.
__________________
Weather today: Hot. Humid. Potholes.
Eatadonut is offline   Reply With Quote
Old 10-13-05, 08:55 PM   #16
MnHPVA Guy
Senior Member
 
Join Date: Aug 2005
Location: Minneapolis, MN
Bikes:
Posts: 758
Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 1 Post(s)
Quote:
Originally Posted by Eatadonut
Also, remember that there's no way you'll be applying more force to the chain this way than a fixie would skidding.
How so? Weight transfers off the rear wheel on decelleration and onto it on accelleration.

Regarding gearing for drag racing to 20 mph;
Most of the recommendations have been for a single gear.
I entered a double elimination 50 meter drag race a couple of years back at an HPV event. Most of the 12 other racers used one or 2 gears. I used 155mm cranks, a 34t chainring and 5 gears in the rear, shifting every couple of seconds. I think the cogs were 24-21-18-16-14. I never stood on the pedals, just sat and spun.

None of the runs were even close. I was always able to ease up before the finish to conserve energy for the next run. I needed to because at 57 years old I was at least twice the age of the average competitor.

"Old age and treachery always overcome youth and strength"
MnHPVA Guy is offline   Reply With Quote
Old 10-13-05, 09:51 PM   #17
highspeedcycle
Senior Member
Thread Starter
 
Join Date: Apr 2005
Bikes:
Posts: 145
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
did you beat everyone?
highspeedcycle is offline   Reply With Quote
Old 10-13-05, 09:57 PM   #18
Brian
Senior Member
 
Brian's Avatar
 
Join Date: Nov 2004
Location: Between the mountains and the lake.
Bikes: 8 bikes - one for each day of the week!
Posts: 16,683
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Of course he did, he's old and treacherous.
Brian is offline   Reply With Quote
Old 10-13-05, 10:39 PM   #19
Hal Hardy
Senior Member
 
Join Date: Apr 2004
Location: NoVa
Bikes: Tour Easy recumbent, Giant Boulder SE with an Xtracycle attachment
Posts: 300
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Quote:
Originally Posted by Stacey
You might want to look in to energy storing mass such as a flywheel. Spin the flywheel up, engage the rear dirve and off you go.

A low racer recumbent would be a good platform. The link has an extreme example. It's the third bike down. I wonder if anyone's learned to ride it yet?

http://www.dclxvi.org/chunk/meet/outside/index.html

Last edited by Hal Hardy; 10-13-05 at 11:09 PM.
Hal Hardy is offline   Reply With Quote
Old 10-13-05, 10:45 PM   #20
cranky
Senior Member
 
cranky's Avatar
 
Join Date: Apr 2003
Location: Redwood City, CA
Bikes:
Posts: 158
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
How about a Trebuchet Bike? Using the same principle of storing energy into a flywheel, only you put it into a weight. Pedaling in a low gear with pulleys lifts a heavy weight, release the weight to propel the bike.
cranky is offline   Reply With Quote
Old 10-13-05, 11:04 PM   #21
icithecat
old codger
 
icithecat's Avatar
 
Join Date: Sep 2004
Location: Victoria B.C.
Bikes:
Posts: 1,124
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 1 Post(s)
Quote:
Originally Posted by biodiesel
Then you just need a can of NOS.
Or a chilli burritto.
icithecat is offline   Reply With Quote
Old 10-14-05, 12:10 AM   #22
Eatadonut
You know you want to.
 
Eatadonut's Avatar
 
Join Date: Jun 2005
Location: Norman, Oklahoma
Bikes: Pinarello Prince, 1980's 531 steel fixie commuter, FrankenMTB
Posts: 1,896
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Quote:
Originally Posted by MnHPVA Guy
How so? Weight transfers off the rear wheel on decelleration and onto it on accelleration.

True. Obvious solution: someone try it, and we want pics!
__________________
Weather today: Hot. Humid. Potholes.
Eatadonut is offline   Reply With Quote
Old 10-14-05, 06:07 AM   #23
Stacey
Non Tribuo Anus Rodentum and off to the next adventure (RIP)
 
Stacey's Avatar
 
Join Date: Dec 2002
Bikes:
Posts: 9,161
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Quote:
Originally Posted by Hal Hardy
A low racer recumbent would be a good platform. The link has an extreme example. It's the third bike down. I wonder if anyone's learned to ride it yet?

http://www.dclxvi.org/chunk/meet/outside/index.html

That's exactly what I'm talking about.
__________________
Stacey is offline   Reply With Quote
Old 10-27-05, 03:52 AM   #24
duckliondog
Senior Member
 
duckliondog's Avatar
 
Join Date: Jun 2005
Location: San Diego
Bikes: Cinelli Unica, BP Stealth, K2 Razorback, Steel Bianchi roadie, Bianchi Super GL, Specialized Stumpjumper, and 3 beach cruisers
Posts: 427
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
You need to be able to put all your energy into the rear wheel. Including arm power.
duckliondog is offline   Reply With Quote
Old 10-27-05, 05:34 AM   #25
2manybikes
Dog is my co-pilot
 
2manybikes's Avatar
 
Join Date: Jun 2003
Bikes: 2 many
Posts: 15,766
Mentioned: 2 Post(s)
Tagged: 0 Thread(s)
Quoted: 130 Post(s)
You mean a bicycle that is a dragster ??
2manybikes is offline   Reply With Quote
Reply


Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off



All times are GMT -6. The time now is 09:47 AM.