WhyFi

Exactly. He keeps talking about how little the "randos" know, but he's approaching this as if spinning out is the one thing holding him back as opposed to, you know, the exponential power requirements to force your way through the air at increasing speeds.

WhyFi

Another thing to keep in mind is that these calculations are requirements to maintain speed. To actually accelerate up to that speed is going to require even more power. This will become more and more problematic the further above FTP you go because you're getting to the very pointy bit of your power curve and you need time to actually accelerate.

bakerjw

Hey, I'm interested to see the final build and result.

I see a lot of the same people make snarky comments here quite often. I've seen their type on group rides, picking apart every thing wrong a first time riders bike or equipment. The sad part was that many of the first timers would not return.

GrainBrain

mstateglfr 

Have you really not seen the actual statistical backing for the comments that go against the OP? These posters arent picking apart a first time rider's bike or equipment- they are instead commenting on the statistical improbability of an experienced rider being able to do something he is boasting about.
If the boasting didnt exist, the pushback also wouldnt exist.
2 way street and whatnot.

Totally different scenario from your comment about 1st time riders on a group ride.

mstateglfr 

I respect people who try and fail vs never trying too.

I also respect people who understand what they are trying to do more than people who ignorantly go into something without a full understanding. Oh, and I respect people who dont mock others while living within their delusion.

livedarklions

I'm actually psyched to see what he can do with this. I just think he unnecessarily set himself up for "failure" by ridiculously asserting that 50 mph is a no-brainer (unless he's on a recumbent). He'd be setting a world record if it's not faired, and he'd be very close to a 33 year old world record if it's faired.

I have doubts he'll get it rolling starting in 70x11, but it's an interesting experiment, and if it doesn't work, he'll just have to add a lower "starting" gear. That should be a relatively easy mechanical fix.

Just to be clear--I wouldn't consider it a "failure" if he doesn't hit 50 mph. Saying he is going to do that for sure is the only truly silly thing he has done.

Lemond1985

And speaking of projecting one's inadequacy, WTF is this guy trying to compensate for? It's gotta be something deeply personal.

Shimagnolo

Well, he is obviously in the mountains, and we know he damned well didn't climb there, so I figured he just wanted to get the most out of his descent.

Maelochs

Most of us are. The rest, aren't in this thread.

With that sort of leaping ability you ought to consider a career in track and field.

After I read your comment, I went back to the start of the thread. Nobody said anything snarky until @DrIsotope noticed the guy was planning a 70x11 singlespeed---and that struck Dr. Isotope as ridiculous (considering that the gearing goes way beyond human capacity, some might suggest a smaller chain ring for greater utility.) Then the OP tried to explain that he was stronger than Superman, while insinuating that the rest of us were underweight wimps. All good fun so far.

As for how any of us treat new riders at a group ride ... sorry about your problems. Next time you go to a group ride, bring some thick skin and some confidence.

Or maybe ... you feel guilty because the guys you ride with picked on some new rider and you didn't stand up for him or her?

In any case .... you might not have noticed, but this is a website, not a group ride. And the OP has plenty of posts and plenty of experience. Also, the OP seems well able to defend himself.

Dr. Isotope called the idea of a 70x11 singlespeed "nonsense" because he did the math and figured out that to ride to 50 mph on a conventional bike would take more power that Sir Chris Hoy could put out, and would break all existing speed records by a considerable margin--sort of if I came here looking for good running shoes, claiming i was going to run a one-minute mile.

OP responded, "Hey it's the guy who can't climb mild gradients with a 38t-11t. Even 48t-11t must be nonsense for you." So basically, Dr,. Isotope said, "Physics and human physiology," and the OP responded, "You're a weak wuss."

Kind of hard to see who is actually being mean to whom, there.

Whatever. It is assumed that we are all adults here, or experienced internet users, who don't melt when someone says something other-than-laudatory.

This thread seems to offer excellent entertainment prospects for several weeks to come. Let the posters have their fun. Sooner or later this thread will have to deliver cell phone video of a rider trying to turn that gargantuan chain ring which started the thread, and we shall all be entertained, however fast he goes.

MattTheHat 

After following this thread with much interest and with the consumption of no small amount of popcorn I believe I've figured it out. The OP is almost certainly the guy from the Liberty Mutual commercial who likes to customize his bicycle. With all due respect. I should have said with all due respect.


-Matt

woodcraft

With the OP's proposed gearing, the rider would go almost 45' with one rpm,

so you would see his leg go one third of a revolution across the frame.

livedarklions

I might have paid you money not to post that commercial. Man, I hate Liberty Mutual's "funny" ads.

MattTheHat 

PM me...we can work something out.

-Matt

AlmostTrick

^^^ 100% Spot on. ^^^

---------------------------
@tellmethetruth What are your accomplishments (speed wise) so far? Have you pushed 45, or 40 mph on the level? You know, standard bike, no fairings, motors or any other "cheats"? Surely you've not only thought this out throughly, but have attempted similar feats many times previously. Maybe you spun out at 45 and went back to the drawing board.

livedarklions

Too late--the damage was done.

Meanwhile, back at the big crank thread.....

Skipjacks

70T?

Did that come in a box marked 'automotive flywheel'?

https://www.autopartswarehouse.com/e...l?Ntt=Flywheel

jadocs

Subbed

CliffordK

Those have been on E-Bay for quite some time. I've posted a few links on occasion.

I did pick up a really big 1/2" pitch ring that was about 1/4" wide at the local recycler. I assume made for gocarts or something.

There are also a few 60T rings, and a 61T ring with ramps and pins (or there was at one time).

robnol

dumbest bike ive ever seen....

tellmethetruth

I've hit over 65-70 kph on a flat, no fairings, on a 52/11, road/tt bike (non-pro aero frame and tt bars). Just under 5km distance.
The reason I jumped to 70t, was because of how easy the 52t felt. I don't want to buy new chainrings every few weeks jumping 2-3 extra teeth. So I bought what I think I can handle, and I work up to that.
I've been cycling all my life as many have, and I think it's natural for me.
The reason I'm converting to single speed is to gain gear efficiency, and because ever since I started cycling, I've only used the highest gears, for climbing, flats, etc.

Most people on here who are shocked about this, and measure up to world records, don't realize that not everyone wants to be a pro cyclist, a world record holder, or famous, and there is always someone better than the best.
I think most people here are stuck in the mindset that cycling is strictly an endurance sport. It is to some degree, but it's not.

DrIsotope

Making some necessary assumptions based on the OP's vaguish nature, but for a cyclist of average height and weight (5'10", 150lbs) in a phenomenally aero position with a 52/11 gear, 65kph (40.4mph) would require a cadence of ~110rpm and a power output of roughly 1,000W. Not outside the realm of possibility until the distance becomes 5km. OP states "just under" so let's round it down to 3 miles even. At 40.4mph, a mile clicks by every 89 seconds, so the above-mentioned power would need to be sustained for 4m27s, give or take.

Take the power and divide it by the rider's weight to get a figure of 14.7W/kg. This is an utterly exemplary amount of power, as the best Tour cyclist in the world can sustain just under 8W/kg for that duration. If the OP could produce even 2/3 of the effort he is now claiming, he would be one of the most-- if not the most-- powerful cyclist(s) in the world. What he's claiming now is simply implausible.

tellmethetruth

Oh my poor friend...don't you know hitting 500 watts by a 5'5" 100ibs, 20% bf, is much different than a 6'5" 245ibs. 9% bf?
It's great you can throw some numbers into a cycling calculator, but there's more to it. Did you factor in frame size, leg inseam, muscle mass, VO2, crank arm length, etc? Do you understand the physics of what an extra 5-20 mm crank length, or + avrg 3-6 in length inseam, what kind of difference that makes in watts? Maybe you can weld some metal together, but you should brush up on your physics, anatomy and physiology.

HTupolev

Without a large tailwind? You should take up track racing.

World record in the 4km individual pursuit is 58kph. That's from a standing start on a fixed-gear bike, but even so, someone of your abilities should be able to beat it by a few kph.

DrIsotope