2015 Post Your Singlespeed/Fixed Gear Megathread
#2551
Calamari Marionette Ph.D
Butt rockets add downforce, and the purpose of downforce is to allow a bike to travel faster through a corner by increasing the vertical force on the tires, thus creating more grip. The formula for downforce of a saddle mounted Butt Rocket is given by
Duh.
This was not copy and pasted from wikipedia.
Duh.
This was not copy and pasted from wikipedia.
Also, one should not confuse drag with down force. The former can exist without creating the latter.
I can assure you though, that the bottles do create down-to-side forces. Dangerous down-to-side forces. Because the bottles are not centralized on the machine, and mounted equal to/aft the rear axle, any down-to-side force behaves as a lever and reduces weight at the front contact patch, creating a dangerously unbalanced weight distribution. This will necessitate a rider to go much slower through corners, or experience crashes due to front wheel washouts.
Please be careful. Remember, I tested this on my driveway.
#2553
- Soli Deo Gloria -
Join Date: Aug 2015
Location: Northwest Georgia
Posts: 14,779
Bikes: 2018 Rodriguez Custom Fixed Gear, 2017 Niner RLT 9 RDO, 2015 Bianchi Pista, 2002 Fuji Robaix
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469 Posts
I've tried behind the seat mounts and clamp on frame mount and find it easier to reach behind rather than reaching down while pedaling fixed. The only problem with behind the seat is putting the bottle back. Once I got used to where the cage was it was no big deal.
As an aside, any calculation of downforce, coefficient of friction, polar moment of inertia, lateral acceleration, etc., must take into account the fact that G = (6.67428۪ ± 0.00067)(10^-11)(m^3)( kg^-1)(s^-2).
As an aside, any calculation of downforce, coefficient of friction, polar moment of inertia, lateral acceleration, etc., must take into account the fact that G = (6.67428۪ ± 0.00067)(10^-11)(m^3)( kg^-1)(s^-2).
Last edited by TimothyH; 11-12-15 at 12:55 PM.
#2554
[MENTION=362748]SquidPuppet[/MENTION]
Those damn down-to-side forces. I always forget about them.
Those damn down-to-side forces. I always forget about them.
#2555
Schindelhauer Viktor modified -
H Plus Son SL42 Rims
Vittoria Rubino Road Tires (700x23c)
SRAM Automatix 2-Speed Rear Hub
Profile Design Svet Carbon Basebar
Bontrager RXL 17 Deg. Stem
Shimano BL-TT78 TT Levers
VDO M2 WL Computer
TorHans VR Aero Bottle
XLC KS-B01 Bottom Bracket Kickstand
XLC ST-L01 A-Head Stem Extension
White Industries Urban Pedal/Bruce Gordon Toe-Clips
Fabric SCOOP Radius Elite Seat
H Plus Son SL42 Rims
Vittoria Rubino Road Tires (700x23c)
SRAM Automatix 2-Speed Rear Hub
Profile Design Svet Carbon Basebar
Bontrager RXL 17 Deg. Stem
Shimano BL-TT78 TT Levers
VDO M2 WL Computer
TorHans VR Aero Bottle
XLC KS-B01 Bottom Bracket Kickstand
XLC ST-L01 A-Head Stem Extension
White Industries Urban Pedal/Bruce Gordon Toe-Clips
Fabric SCOOP Radius Elite Seat
Last edited by The Pusher Man; 11-12-15 at 01:08 PM.
#2556
Calamari Marionette Ph.D
Looks like manure though, IMO.
#2558
Senior Member
Join Date: Feb 2014
Location: SD
Posts: 2,745
Bikes: Handsome Fredward, Trek 1.1
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47 Posts
I just use one of these >>> https://www.universalcycles.com/shop...s.php?id=44338
Looks totally uncool, but then I'm not a very cool guy anyway.
Looks totally uncool, but then I'm not a very cool guy anyway.
#2559
Senior Member
Join Date: Feb 2014
Location: SD
Posts: 2,745
Bikes: Handsome Fredward, Trek 1.1
Liked 131 Times
in
47 Posts
Schindelhauer Viktor modified -
H Plus Son SL42 Rims
Vittoria Rubino Road Tires (700x23c)
SRAM Automatix 2-Speed Rear Hub
Profile Design Svet Carbon Basebar
Bontrager RXL 17 Deg. Stem
Shimano BL-TT78 TT Levers
VDO M2 WL Computer
TorHans VR Aero Bottle
XLC KS-B01 Bottom Bracket Kickstand
XLC ST-L01 A-Head Stem Extension
White Industries Urban Pedal/Bruce Gordon Toe-Clips
Fabric SCOOP Radius Elite Seat
H Plus Son SL42 Rims
Vittoria Rubino Road Tires (700x23c)
SRAM Automatix 2-Speed Rear Hub
Profile Design Svet Carbon Basebar
Bontrager RXL 17 Deg. Stem
Shimano BL-TT78 TT Levers
VDO M2 WL Computer
TorHans VR Aero Bottle
XLC KS-B01 Bottom Bracket Kickstand
XLC ST-L01 A-Head Stem Extension
White Industries Urban Pedal/Bruce Gordon Toe-Clips
Fabric SCOOP Radius Elite Seat
#2562
Member
Join Date: Nov 2015
Location: Sachse, Texas
Posts: 28
Bikes: Aventon Mataro, Orbea Avant H50, Orbea Orca M30
Likes: 0
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0 Posts
I'm very new to all this bike riding. But so far I really enjoy it. Here is my bike at the moment. I just need to install my rear wheel and adjust my seat. I'm about to order a new crank, pedals, and carbon fork.
#2566
Clark W. Griswold
Join Date: Mar 2014
Location: ,location, location
Posts: 14,652
Bikes: Foundry Chilkoot Ti W/Ultegra Di2, Salsa Timberjack Ti, Cinelli Mash Work RandoCross Fun Time Machine, 1x9 XT Parts Hybrid, Co-Motion Cascadia, Specialized Langster, Phil Wood Apple VeloXS Frame (w/DA 7400), R+M Supercharger2 Rohloff, Habanero Ti 26
Liked 4,564 Times
in
3,055 Posts
Schindelhauer Viktor modified -
H Plus Son SL42 Rims
Vittoria Rubino Road Tires (700x23c)
SRAM Automatix 2-Speed Rear Hub
Profile Design Svet Carbon Basebar
Bontrager RXL 17 Deg. Stem
Shimano BL-TT78 TT Levers
VDO M2 WL Computer
TorHans VR Aero Bottle
XLC KS-B01 Bottom Bracket Kickstand
XLC ST-L01 A-Head Stem Extension
White Industries Urban Pedal/Bruce Gordon Toe-Clips
Fabric SCOOP Radius Elite Seat
H Plus Son SL42 Rims
Vittoria Rubino Road Tires (700x23c)
SRAM Automatix 2-Speed Rear Hub
Profile Design Svet Carbon Basebar
Bontrager RXL 17 Deg. Stem
Shimano BL-TT78 TT Levers
VDO M2 WL Computer
TorHans VR Aero Bottle
XLC KS-B01 Bottom Bracket Kickstand
XLC ST-L01 A-Head Stem Extension
White Industries Urban Pedal/Bruce Gordon Toe-Clips
Fabric SCOOP Radius Elite Seat
#2567
Senior Member
Getting back to the ass rocket thing....
Thought that this set up was slick. Specialized Zee cage and an XLab Delta mount. It seemed to fit absolutely perfect, and it was actually hard to get the bottle in and out sometimes. Thought I would be safe with this and it would never launch. It survived railroad tracks and potholes. All was good, until it launch after hitting a small crack on the local MUP. Never found that bottle either. Never heard it hit the ground. Only found out it was gone when I went to take a drink and I reached back to grab nothing.
Thought that this set up was slick. Specialized Zee cage and an XLab Delta mount. It seemed to fit absolutely perfect, and it was actually hard to get the bottle in and out sometimes. Thought I would be safe with this and it would never launch. It survived railroad tracks and potholes. All was good, until it launch after hitting a small crack on the local MUP. Never found that bottle either. Never heard it hit the ground. Only found out it was gone when I went to take a drink and I reached back to grab nothing.
#2571
Brown Jersey Winner
****yes purple!!
very important question: did you get the right size chainring bolts for that 44arn chainring or did you have to get some special length ones fab'd?
shoutout to hamfoh- thems is JOKES! i was FOOLIN Y'ALL!
very important question: did you get the right size chainring bolts for that 44arn chainring or did you have to get some special length ones fab'd?
shoutout to hamfoh- thems is JOKES! i was FOOLIN Y'ALL!
#2572
Clark W. Griswold
Join Date: Mar 2014
Location: ,location, location
Posts: 14,652
Bikes: Foundry Chilkoot Ti W/Ultegra Di2, Salsa Timberjack Ti, Cinelli Mash Work RandoCross Fun Time Machine, 1x9 XT Parts Hybrid, Co-Motion Cascadia, Specialized Langster, Phil Wood Apple VeloXS Frame (w/DA 7400), R+M Supercharger2 Rohloff, Habanero Ti 26
Liked 4,564 Times
in
3,055 Posts
#2573
I don't use chainring bolts. Instead, I tie my chainring to my crank arm using grey hairs from my beard.