Genesi 29 @ 50mph??? Frame choice

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mapbike

Well-Known Member
Mar 14, 2010
5,502
109
63
Central Area of Texas
I see posts here all the time re bike parts that failed due to vibration resulting in riders thrown to the ground and doing hospital time. Pictures of broken frames, seized motors, bearings and gears all torn to crap.

You never see any of this stuff eh?

Like I said, do whatever you want. If you have no fear of doing 50 on a bike that was built for 15 powered by a vibrating pot metal motor assembled in a shop with a dirt floor that cost $50 to make, by all means.

As I mentioned, put some flat bars on that thing and tuck in. That should get you 55 - :)
Yee Haw.............!

No I don't see those post all the time like you speak of, main thing I have seen in the last couple of years has been a fender failure and bairdco have a nasty spill because of a bolt coming out on his front drum brake set up which I think he blamed his self for because he may not have tightened it up properly, a few years ago I seen at least one post of a Huffy frame that had broken close to the seat post area, but off the top of my head I cant remember the last time I have seen any of the post you speak of Mike, put all the links here and enlighten me please sir?

Map
zpt
 

Mike B

New Member
Mar 23, 2011
2,256
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Central CA
Yeah, that's what I'm talking about. In addition to all the busted rings, gouged out jugs, metal shavings in motor and all the other problems you get with a fifty dollar motor.

If you want to trust your life to a fifty dollar motor at 50 MPH, by all means have fun!

You even said that you don't want to anymore. You said your wife was shocked at how fast you were going. You agreed that it was too fast and you are installing larger sprockets to keep the speed down.

Your wife seems concerned about how fast you go. I can assure you that I do not. I only care how fast I go. But you better do as your wife tells you - :)
 

mapbike

Well-Known Member
Mar 14, 2010
5,502
109
63
Central Area of Texas
Yeah, that's what I'm talking about. In addition to all the busted rings, gouged out jugs, metal shavings in motor and all the other problems you get with a fifty dollar motor.

If you want to trust your life to a fifty dollar motor at 50 MPH, by all means have fun!

You even said that you don't want to anymore. You said your wife was shocked at how fast you were going. You agreed that it was too fast and you are installing larger sprockets to keep the speed down.

Your wife seems concerned about how fast you go. I can assure you that I do not. I only care how fast I go. But you better do as your wife tells you - :)
Yes, I said 50 MPH is in my opinion to dang fast on my bikes, and yes I plan to slow mine down.... I will still cruise in the low 40's and spend most of my riding time in the mid to upper 30's probably, for multiple reasons, safer and the engines last longer when they dont get reved out of their mind all the time, Mike I have had pretty good reliability out of my engines, the first one I installed back in 2009 is still running strong after a few thousand miles, the BGF engine I have on the Huffy is another older engine, its not a fast bike at a cruise speed of 32-34 MPH but a nice dependable rider and it has around 1400 miles on it now, several people on here have built the engines right and run a quality oil and get lots of miles out of them, but if they aren't built right they dont last long and some people just dont know how to do them right.

they are a crap shoot like most things Chinese but the good thing about them is that they're cheap enough that you can play for not a lot of dough and replace things pretty easy, for me the whole thing is a hobby I have every intension on spending some cash on, my motorcycles are for the long haul.

The wife is happy that I plan to hang up my 50 MPH boots and just cruise at safer speeds....

its all in good fun Mike, I understand all you say and the concerns you speak of.

peace, map
 

Mike B

New Member
Mar 23, 2011
2,256
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Central CA
Yeah, I saw those bikes in the pics. That really got my interest.

Why would a guy with 2 good motorcycles want to be doing 50 on a bicycle powered by a happy time? Death wish? Why bother?

Don't be "saving" those motorcycles for the "long haul", they need to be run down the road regularly. Like anytime you need to be going 50. Or 40 for that matter.

You got 'em, they are paid for, much safer and don't even use that much gas. Like what, twice as much?

Is your life worth 10 cents a mile? (based on 50 more MPG at $5/gal)

I dunno why you did this 50 MPH quest, only you know. And it's a good thing that it's over - :)
 

mapbike

Well-Known Member
Mar 14, 2010
5,502
109
63
Central Area of Texas
I agree for the most part of what you said here Mike, I ride my Harley pretty regular when weather permits and I need to get new tags on the old 1982 Yamaha 650, I also have a 08 Rocketa 150cc scooter that is a hoot to ride, I've done a cew mods to it and it will run 62 mph as long as its flat ground and no big head wind, haven't tagged it in a couple years though, but its a fun rids around town and it gets about 80+ mpg.

My motorcycles are fun and great tranportation but the motorized bikes are a hobby and gives a busy body like myself somethjng to do, im a full blown tinkerer and this time of year the motorized bikes are my focus, I'm really not a speed demon anymore like when I was much younger but Im still a thrill seeker to a lesser degree and like to push things just a little sometimes just to see what I can do.

I honestly didn't know if I would ever get to the 50 mph mark and always figured if I got in the mid 40's I'd be happy, but once I seen that maybe I could get it done I figured I'd go for it and if I done it then I'd back down to safer speeds and just always have that satisfaction in my own mind that I did it, I dont recommend anyone else do it though, I'll be completely honest with you Mike the last day I run those speeds something happened that I took as a warning sign and until now I've only told my wife, the last and fastest run I made that day with the stock cdi was 50.3 mph, I rode the bike home after that run and parked it in the shade out beside the chicken house, I was in my current shop tinkering with some parts for my newest build and all the sudden I heard what sounded like a gun shot....I went out to investigate the loud boom and found that the front tire on that bike had blown out while just sitting there in the shade, the tire was fine and the tube was fine all accept that the entir e valve stem seperated from tube and blow completely out of tube and wheel, tubes were heavy duty type and tire wasn't over inflated, just a freak thing that I have never had happen before, imagine if I had been zipping down the road at 50 mph and that had happened.....? Ouch.... I had on gloves and helmet but it still would have got real ugly.

I figured the good Lord was telling me right then and there it was time to slow it down and I am.....!!!

So yeah 50 mph club is something I honestly can say I qualify for but on a regular bicycle Im done with it, I came I saw and I did it and now im gonna relax a bit and build my bike for a safe comfortable. Ruise speed and enjoy the ride, the tube that blew was a bit small for the tirs I thought even though it was listed for it, the bike now has a nice set of Kenda Kiniption tires and new heavy duty tubes designed for the big tires.

Map
 

Master-shake

New Member
Feb 24, 2013
315
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texas
I need more power I think. My engine tops out at 34 mph on level ground with no wind (I ride an onex) I want to get up to the forty mark no higher really.
 

scotto-

Custom 4-Stroke Bike Builder
Jun 3, 2010
6,505
24
38
Ridin' inSane Diego, CA.
My bike handles fine and solid at 65mph, though I rarely ride or race it at that speed. And as I've said many times before this bike is built for racing and is not meant for the street or an example of what anyone should build.

If you're not an experienced cyclist or motorcycle rider/racer.....this is not a bike you want to build as it can more than get you killed in a heart beat!!!

But for me it is so much fun to ride.....I just don't mind going fast in a safe manner and I mean fast!

And yes, you could gear this bike to exceed 80mph.......but why would you want to?



Yeah it's well built and has been proven to do the speeds it does for all the nay-sayers that just speculate.....

....and no I never advise anyone to do as I do, just so you know.
 
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Albula vulpes

New Member
Mar 16, 2010
419
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FL
My first MB was an Ebay HT/China girl kit I put on a new Magna Rip Curl that I got from Target. It's top speed was 28mph, and it didn't make it 1,500 miles without falling apart.
 

scotto-

Custom 4-Stroke Bike Builder
Jun 3, 2010
6,505
24
38
Ridin' inSane Diego, CA.
My first MB was an Ebay HT/China girl kit I put on a new Magna Rip Curl that I got from Target. It's top speed was 28mph, and it didn't make it 1,500 miles without falling apart.
Cuz it was, what it was......there is a difference. There is cheeeeeeeeeeeeeeeap and not so cheap! Lot's of other factors as well. Know what you're building and ride appropriately!

If you build it and it doesn't feel right, it probably isn't ! Make it right or move on to something else.......simply put.
 

Albula vulpes

New Member
Mar 16, 2010
419
0
0
FL
It served it's purpose. Got my feet wet. I have a Japanese engine now. If my HT/China girl only went 28mph, and these guys are getting 50mph out of them putting them on Walmart bikes, I can't imagine how long they last. Again my bike didn't make it 1,500 miles.
 
Dec 11, 2014
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Tucson
There is not much perspective in some of the arguments. I don't talk about what we achieved in our last test sessions so as not to get blasted. I road raced ASMA superbikes for 3 years and there is fun in this that plain did not exist there. We have a rural road to test on with no side entrances for almost four and a half miles. We send the chase truck ahead to spot and they tap brake lights if there is another vehicle of any type or any reason to slow. We finally tested on nitro blend and blew past the chase trucks top speed by around 20 to 25mph faster than it could go. We no it can do it now but don't have a safe way to test so it's on the shelf until we figure it out. Anyway if you want to do 50 or 100 on a bicycle have at it just don't endanger others and share your story.
 

YesImLDS

Member
Jun 29, 2013
960
12
18
Columbia, Missouri
While my 26" rims have hit 47mph I don't think I'll be going that fast anytime soon again on a real cheap wally world bike like my build has been. I recently changed out the rear rim due to a missing spoke and opened up to check how the bearings were. Out of one side three ball bearings fell out like it was nothing. The grease was cooked up in there pretty good. Given this was a coaster brake rim and I hadn't touched it in the time that the motor had been on the bike, it was looking like at some point it was going to give out. At 40mph plus I don't think I would had had a fun time. Upgraded rims are awesome anyways just cause they have more strength to them.
 
Dec 11, 2014
628
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Tucson
Wheels and tires are definitely the problem at really high speed. I truly thought the high end bearings, rigid thru axles, and quality tires would be fine but they have an extremely short life span at those speeds. I did quite a bit of testing and it seems I found a good rule of thumb. You can take a wheel or moving part up to about two times it's intended design parameters and it should be ok. I had always heard of a safety factor of two and that is right at that. What I was surprised to learn is if you push to say 2.2 or 2.3 in other words even a bit over double the speed or load you will quickly see failure or signs that it is coming apart.
 
Dec 11, 2014
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Tucson
The wheels on a bicycle are really the dangerous part. The frame does not know how fast it's going just how much vibration and twisting loads are being put on it. Vibration and loads might well be worse at 15mph than 60 which is what I ran into ha ha. And the drive assembly, well other than one member on here I don't think most of us are pedaling at twice the rpm and loads that the bike can handle. Anyway have fun, find an appropriate place, and check those wheels all the time.
 

boxcar

New Member
Dec 18, 2014
358
4
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Astoria OR
I haven't posted here for a while. Didn't have much to say and have been very busy with other things.
I have always loved this sight and the sport because of the friendly helpful way that most disputes are handled by the members.
This thread disturbed me.
Name calling is the lowest form of stupidity.......
And serves no purpose but to inflame others. Shame........
I recently had the opportunity to take my bike to 53 mph.... Very steep long hill.
I run a GPS all the time . It was interesting . I'll never do it again .
The bike , a well built CG powered cruiser designed and built for the low to mid 30's , was very smooth at that speed ( 53 mph ) but it was like flying an ultralight plane at 200 mph . Twitchy, is about the best I can describe it.
I don't think advocating anything over mid 30's is a wise idea for many reasons. All engineering related.
But this is a free world , or at least it is supposed to be.
My opinions are my own .And your's is just that. You have the same rights as I to post them. I will always respect that.
Map , I love ya man. Just be safe.... Or as safe as your thrill seeking side will allow......
 

Slogger

Member
Sep 8, 2014
544
4
18
nohio
There's a saying among pilots- "There are old pilots, and there are bold pilots. There are very few old, bold pilots."
Being a lifelong motorcyclist I have no interest in speedy travel on my rigid framed aluminum torture rack of a bicycle, but what others do is their own business.
I do wish they would avoid attention of the authorities when they go out to weave through traffic, pass on the right, startle drivers by splitting lanes in town and running red lights.
The entire hobby can be wrecked with the stroke of a pen in the state capitol.
Just something to consider.
 

Tony01

Well-Known Member
Nov 28, 2012
1,729
1,721
113
sf bay area
Aluminum bikes are a bad idea.

I think BonusParts back in 2014 was BSing about 40+ over 1k miles. He had attached his gas tank no more than a month before he said that.. a thousand miles in a month.. yea sure. I will do 50 miles in a day, but not five days a week.

Aleman, I don't think wishing an accident on anybody is wise, except on the socialists currently running our country.

You might think going fast is stupid. Well, I think the large percentage of people on this board, who wear bicycle helmets, half-helmets, or no helmets at all are stupid. I mean, REALLY stupid. Apparently 30% of full-face helmet damage is on the chin cage (according to ADVrider forums).

My bike does 51 with tall gearing, with even taller gearing I bet I could hit 60. Point? so i could cruise at 45 with the traffic. It's the people who are going too slow or too fast for the traffic, that get in the worst accidents. Mostly the ones that go too fast for the traffic, like that e-bike video lane sharing at double the speed of traffic.

At over 50mph you start needing power to overcome air resistance.

Here in CA the max legal speed is 30, but I've been lucky so far in my first 500mi with the local police. Have ridden alongside police, gone thru intersections at 40+ with cops giving me thumbs up and the nod. You know why? Because I wear a full face MC helmet, knee pads, gloves, have registration, they see me looking around and being aware of surroundings, and not riding like a general lane sharing idiot.

Going 50 is more about judgement of road conditions and bike build, than anything else. I did 55mph going down a short hill, and that was enough. I'm good with high 40's.
 

langolier

Member
Jul 6, 2015
57
0
6
Wisconsin
35-40 is about my limit, anything past that I will want to be on my motorcycle that has 4X the stability and braking. With that being said in my state (WI) the DMV allows us to ride on the roads without license provided we stay under 30 mph and a certain size motor. If we keep pushing beyond the limits those privileges will go away. How fun that would be .......... So let's be responsible to ourselves AND to others. Thanks for letting me rant. Be safe out there.