Genesi 29 @ 50mph??? Frame choice

GoldenMotor.com

Gp masta

Member
Apr 17, 2014
84
4
8
Miami, Florida
Well I manage to go 50mph on 29r. I am thinking of going with the Gta2 frame set up .... My question is if i switch to a 26 frame set would i gain any more mph???
 

Kioshk

Active Member
Oct 21, 2012
1,152
10
38
Connecticut
Mine with a 44T gear tops out at about 32MPH. Can't recommend going faster though...not worth the risk.
 

Kioshk

Active Member
Oct 21, 2012
1,152
10
38
Connecticut
Thats pansy talk. I've done 40+ for over 1000 miles. No problems. My only accident occured at under 30mph.
LOL

Well then, I'm a 280# muscle-bound pansy talkin'. I too had my only accident under 30-MPH, in fact it was just under 03-MPH. Coming off a concrete slab into some unexpectedly muddy grass...bike slipped from under me, fell on my ass into the mud, and broke my tibia and fibula bad enough to require titanium screws.
 

BonusParts

Member
Nov 28, 2012
168
0
16
SE-PA
LOL

Well then, I'm a 280# muscle-bound pansy talkin'. I too had my only accident under 30-MPH, in fact it was just under 03-MPH. Coming off a concrete slab into some unexpectedly muddy grass...bike slipped from under me, fell on my ass into the mud, and broke my tibia and fibula bad enough to require titanium screws.
Exact reason not to worry about speed so much.

From my reading 8mph is enough to kill you on a motorcycle if you fall the right way, so really its all inherently dangerous.

I look at it this way - IF you have brakes on both wheels, you carefully assembled the bike and you frequently inspect and maintain - the last thing thats gonna kill ya is going 40!

I'll hafta post the video...

http://youtu.be/9HupXQVMANE?t=46s

-matt
 

Kioshk

Active Member
Oct 21, 2012
1,152
10
38
Connecticut
Well, in the second video, that d.o.u.c.h.e blasting through the stop-sign on the walking/bike trail doing 40 MPH in broad daylight (right after a cop-car went through the intersection BTW) is going to end up hurting someone else. Way to represent us to the public!
 

mapbike

Well-Known Member
Mar 14, 2010
5,502
109
63
Central Area of Texas
All this 50 MPH talk makes me laugh a little, it take one heck of a modified engine and the right gearing with a lighter weight rider to get 50 MPH out of a china girl.

only a couple that I know of that have done it and they have done it on highly modified bikes with very small rear sprockets, believe back when bairdco done it on his bike he was running something like a 27T rear sprocket and he is a light weight man.

I honestly dont see a 29'er doing 50 MPH on flat ground, I have GPS'd 45.8 MPH on a 26" wheel bike and a 34T sprocket, not sure what the rpms was at that time but before my tach pooped out on me I had registered 9400 RPM with this engine.

An old friend of mine died in a slow speed motorcycle wreck back in 2008, bunch of friends taking a ride, a lady pulls out in front of him, he sees her and was almost to s stop at only about 10 MPH when he hit the car, he came off the bike and hit his head when he went down and he died.... it dont take much.

Just ride safe everyone and put a brain bucket on when you do, it could save your life.

We need to keep you alive & working because millions on welfare are depending on you!

Map
dnut
 

BonusParts

Member
Nov 28, 2012
168
0
16
SE-PA
All this 50 MPH talk makes me laugh a little, it take one heck of a modified engine and the right gearing with a lighter weight rider to get 50 MPH out of a china girl.


Map
dnut

Abbrev. quote.

Mr Map - I am using the 29er of this style as you may be aware....

I am breaking 50mph. I am planning to use a GPS & a speed sign posted by my local police department. Its in a 35mph zone. The sign reads to 50mph, then the numbers shut off and it just strobes. I seek to bring GPS data + Video.

Also, based on my calculator, a 29er with a 36t should achieve about 52mph at 9000RPM. ASSUMING IT HAS THE POWER ( And thanks the the infamous fred....it does) it will break 50.

You gotta figure, you gain 3" diameter which over the diameter adds a bit. Which i've noticed in my quick maiden voyage really changes the RPMS on it.

I just broke 40 on it that run - I have since switched to my Mikuni VM-18 to unleash the rest of the powerband. I just wanted to run the NT because its always reliable as i have it configured for my temps and elevation.

Anyways blah blah. Im gunning for 50mph. I wont be happy until then.
 

mapbike

Well-Known Member
Mar 14, 2010
5,502
109
63
Central Area of Texas
BP

I am running 49.8 MPH on on of my bikes that has 24" wheels and a 30T sprocket and I weigh 215 lbs, with a bigger carb Im sure I could add maybe 2-3 mph to that top speed, this is with a $59.00 dax Gen IV lower and a jug I did the port work on myself along with a piston I ramped, drilled 12 holes in and notched the skirt on myself, im running a dax Dellorto clone RT carb, a shorty manic mechanic billet intake, a Puch Hi Hi 70cc head and a stock kit exhaust pipe that is gutted and has had the small exit tube removed and the end cap drilled out large enoug for the engine to breathe, the pipe flange has been port matched to jusg as well as it can be.

This engine will scream at .2 mph short of 50mph and I have about $200 invested in it.

50 mph is doable but the average engine will not ever see those speeds is the point I was trying to make.

I plan to gear this bike so that it will be a bit slower and just have better acceleration, I have done what I set out to do and now I want a safer bike.

50 mph is just to fast on a bicycle in my opinion.

Map
 

The_Aleman

Active Member
Jul 31, 2008
2,653
4
38
el People's Republik de Kalifornistan
Thats pansy talk. I've done 40+ for over 1000 miles. No problems. My only accident occured at under 30mph.
There's a first time for everything. For every 10MPH you attain, you travel 14.66 feet per second. That's roughly a 1 story building. So at 50MPH, you're traveling roughly a 5 story building every second. On a crappy department store bike. Your "no problems" and "my only accident" status come increasing amounts of stress the more time goes on - as does the frame of that generic department store bicycle you use like a cheap drug to get your fix.

Maybe one day you'll be like so many long-lost members here and disappear, never to be seen again. You won't be able to speak of your (possibly first) problem or your (possibly second) accident. If you're lucky you'll be a story on darwinawards.com. Your experience will be of much more use there than here, IMHO.

If that is a Genesis Onyx 29er with just a rear coaster brake on it and you are doing 50mph, you are nuts.
Heh. I'd call it stupid. Absolutely stupid. It takes some mental effort to be nuts. It takes none to be stupid.
 

mapbike

Well-Known Member
Mar 14, 2010
5,502
109
63
Central Area of Texas
Post some pictures of these 50 mph bikes
Actually mine has gone just under 50 mph, posted 49.8 mph on my GPS three differsnt times, my bike is what I would. All a medium weight cruiser frame, 1963 Western Flyer Strato Liner, it is a 26" frame but I'm running 24" heavy spoked steel wheels, nothing super fancy, just 12ga spoked wheel master wheels with a Shimano Coaster rear hub, I have a set of Kenda Kiniption tires for this bike, has this tire on the front already and will be getting one on rear as soon as I get my new hub adapter and larger sprocket, since I want to gear this bike down to a low 40's cruiser with more acceleration, 50 mph on a standard type bike frame is just not smart or safe, I wanted to see if I could get this bike to that point and I have so Im done with those kinda speeds, not worth die- in over.....lol!

I'll post a pic of the bike here as soon as I can.

Map
 

FFV8

New Member
Oct 29, 2013
551
16
0
Spring Valley NV
Well, in the second video, that d.o.u.c.h.e blasting through the stop-sign on the walking/bike trail doing 40 MPH in broad daylight (right after a cop-car went through the intersection BTW) is going to end up hurting someone else. Way to represent us to the public!
Did you mean this video?
https://www.youtube.com/watch?v=ObwH_YbaM4c

If you make it past 45 seconds on this one without screaming at the screen you are doing good:
https://www.youtube.com/watch?v=SdL6C9gKQ_4

Neither one of those guys give us a good name.