Sunday, December 4, 2011

hammerschmidt alternative to schlumf drive

22/36 or 24/38 gear range.
• 1: 1 or Overdrive ranges. 1:1 means the chainring does one full revolution with every pedal stroke. Overdrive is approximately 1:1.6.

Expect the HammerSchmidt to cost between $700 and $800 for the Bottom Bracket, Crank arms and Trigger shifter. Available starting December of this year.

2011 Truvativ HammerSchmidt All Mountain Crankset. Item: TRV118 ActualWeight:"Actual Weight" means we weighed this item ourselves. 1467 g; $649.00 ...



Including spindle, bearings and spider, excluding chainring and cranks: 790g (46 tooth chainring with chainring bolts: 90g, cranks 220g each).
Please compare the total weight of speed-drive with the total weight of a triple chainring set including shifter, cable, derailleur. Example: Shimano Altus (48/38/28 teeth): weight incl. right crankarm: 1255g

D - not really sure what advantage the topic unit offers.

Slightly heavier, costs more.

D - I cannot find an updated gear calculator for all the new drives.

The K-Calc doesn't display properly with their new reduced window size. Lacks many newew gear hubs. Another site wouldn't load at all.


I remain wistful. If I could get a recumbent 'one size fits all' belt instead of chain, I could use it in all 'bent bikes. The weight savings for the long chainline would be considerable.

Friday, October 21, 2011

strange front suspension

D - I saw what initially appeared to be a standard cruiser at the local bicycle shop.
Looking closer, it had a squat lil' spring shock mounted inside the frame just above and behind the front steering tube. I have never seen anything like that before!

D - it looked a bit like this, but was inside the bike frame triangle.
Intriguing, since it raises the suspension to , say, inside a fairing on a 'bent bike.


Aside - for the purpose of my internal-chainline-in-bike-frame SWB 'bent concept, I may have figured out a better way to set up a Freelight dynamo. Basically, I set up kind of a 'mirror image' chainring on the left hand side of the frame (keep in mind the frame is dual side-by-side tubes).
I need clearance away from ferrous frame parts.
I have often lamented that Shimano has the patent on a bottom bracket dynamo, but is not building one- they're just sitting on it. My thought experiment to build one externally went nowhere- I simply could not non-invasively get the clearances required.
Anyway, the pedals spin at pretty much the same rate at any speed, about 60-90rpm, regardless of bike speed - unlike the tires! So the pedals seems the place to locate a dynamo.
By placing the magnets on the edge the rim of a flat disc mounted on the crank axle, we should manage to keep the magnet, mounted on a boom, away from the mass of steel bike parts.
This has the benefit with my proposed bike design to even appear pleasingly symmetrical with the chainring located in the 'mirror image' opposition position.
Possibly inserts to extend the pedals out, often used for those with knee pain, will be needed to gain the necessary clearances.

I've thought through my Freelight 'amber sideways running light' idea.
I've decided that the 3 (not 4) single row LEDs are ideal. I can chop the base so the 3 aim over a broad range of angles. This should address any sideways directions not addressed by the front or rear lights. LEDs are notoriously highly directional.

Who knows- maybe a dynamo could power a music player, or a cell phone on standby when not in use powering lights. This would require more complex power management.
Most current mobile phones currently have standby power in the range of 150 to 300 mW.

I'm thinking about how to incorporate brake/signal lights mounted on the extra-wide 3-basket rear luggage rack.

The left-hand frame tube can be used to route all necessary power cables.

Friday, October 14, 2011

wireless bicycle brake

To brake with the wireless brake, a cyclist has just to clench the rubber grip on the right handle. The more tightly the grip is clenched, the harder the disk brake on the front wheel works. It seems as if a ghost hand is in play, but a combination of several electronic components enables the braking. Integrated in the rubber grip is a pressure sensor, which activates a sender if a specified pressure threshold is crossed. The sender is integrated in a blue plastic box which is the size of a cigarette packet and is attached to the handlebar. Its radio signals are sent to a receiver attached at the end of the bicycle's fork. The receiver forwards the signal to an actuator, transforming the radio signal into the mechanical power by which the disk brake is activated. To enhance reliability, there are additional senders attached to the bicycle. These repeatedly send the same signal. In this way, the scientists hope to ensure that the signal arrives at the receiver in time, even if the connection causes a delay or fails.


D: fancy. Clean looking.
But just running the cables inside the frame can accomplish that.

Update- getting bro-in-law civ engie to run stress calcs on my what-if bike frame.
See 'my entry into bicycle design contest'.
2 parallel side-by-side tubes need to match the strength of a SWB's single monolithic boom.
Note that mine is not perforated by the central tubes from steering and seat post.
My latest tweak makes keeping water out easier.
The chain return line is line with the bottom bracket now.

Friday, August 5, 2011

alfine 11 gear not cheap


Again, my concern is the lack of a very efficient direct drive gear.

Wednesday, July 20, 2011

solar bike concept

The bike also has a third handlebar-mounted panel, along with a 24-volt 1-horsepower motor, a 5000 mah (milli Ampere hour) lithium-ion polymer (LIPO) main battery, two 5000 mah LIPO booster packs wired in series, and a 24-volt controller.

Terry built the solar panels himself, out of eighth-inch polycarbonate sheeting, aluminum, and 18 x 6 x 6-inch (457 x 152 x 152-mm) mono crystalline cells. In order to keep the weight down, he drilled thousands of holes through the aluminum parts. The cells each put out 3.8 to 4 watts, together providing an estimated 8.7 volts of electricity. Using the controller, riders can assign them to charge any two of the three batteries.

nice proof of concept!
I was thinking flexible solar thin film under a partial fairing which is transparent.
Plus mainly to power consumer electronics.

Thursday, July 14, 2011

off road SWB bikes. best of class

D: really, just
Re: Azub Max.

The Azub Max has an offroad variant. I don't know what currency their sites u...

1:20 PM (23 hours ago)
Peter Stull to me

show details 3:07 PM (21 hours ago)

The basis Max frameset is $2200, Basic complete bike is $3200.
D - so comparable to the price of the Meta Bike frameset.
Hmm, Orca is winning for total-setup price.

I confess, the adjustable seat/et al position of the Azub series is unprecedented.
Plus the rear-boom extension for trips allows 2 sets of panniers, like some grasshopper models. It makes me wonder about a DIY rig for the Orca.
I cannot believe the company does not offer that.

Peter Stull
Bicycle Man LLC
Recumbent bikes and trikes
But you see the appeal of my 'long-short wheelbase' layout though.
A lot of the benefit of a 'bent bike is lower air drag.
By adding the 2nd set of panniers lower, we increase front cross section.
In fact, we end up with a profile much like an upright bike when done.

I remain intrigued by the idea of a wide carry rack that could hold an additional folding basket on top.
I have 2 side folding baskets which must be permanently affixed.
I'd like to modify that to have pannier style mounts so they can be removed.
An unlikely benefit of my 24i tires on my youth frame is the additional space between the top of the tire and the rack.
(Recall that I have a Cruzbike.)
I confess that I like the lower centre of gravity with groceries.
I hope to have 2 grocery bags with heavy stuff low and left/right,
with 1 additional lighter one high and mounted on an extra-wide rack.
Those folding baskets match the size of a reusable grocery bag perfectly.
But are darn heavy the rest of the time.
My bike weighs in at 60lbs!

Aside - not too impressed with the Front wheel drive.
My front tire tried to slide sideways when I spun out on gravel uphill.
I suppose on pavement this is not an issue.
But you'd think something with mountain bike tires could go off-road! Nope.

D - I am intrigued by the Meta Bike biz model of just selling frames.
I mean, my 'everyman' 'bent bike entry just uses standard parts anyway.
(Just a very basic chain-inside-frame layout.)
As much as I like the Flevobike Greenmachine, it only comes with 20i tires and
costs about 6000 bux!
Plus I'd prefer if Rohloff released a 580% gear hub for it.

Wednesday, July 6, 2011

d30 gel gloves. review.

D: they looked so promising that I ran out and bought a pair.
For 50 bux, I would not complain.
For 100 plus, I will.
The quality control is terrible.
If you look at the pic, you'll see one of the finger guards is almost 1cm off the placement on the other glove.
And the gel knuckle guard is no better.
The left glove is fine.
But the right glove has it so far over that the right index-finger knuckle is barely covered. Worse, all my friends promptly tested them by punching stuff. So the threading is starting to tear out on that knuckle too.

All in all, not worth the money.

I want my money back.

Saturday, April 16, 2011

we still don'tknow how a bicycle balances

Basically, they took a bike with two small wheels and built in mechanisms that canceled out the caster and gyro effects. Launched at a speed of 5 mph, the bike stayed upright. When it leaned to one side, the bike righted itself. Just like any old bike would. “It’s all about how bicycle leaning automatically causes steering, which can bring the wheels back under a falling bike,” explains Andy Ruina, professor of mechanics at Cornell and a co-author of the Science paper.

So, the key to making a bike unstable is screwing around with a bike’s ability to steer itself. Or by misadjusting the “trail, the front-wheel gyro or the front-assembly, center-of-mass position,” the paper explains in more technical-speak. The researchers expect their work might be used to innovate bicycle design in ways thought impossible before: “The evolutionary process that has led to common present bicycle designs might not yet have explored potentially useful regions in design space.”

Tuesday, January 18, 2011

folding bikes
D: that is the smallest package ever.
D: a trike that folds down, apparently with no tools.
D: I see why my bud Tim bought a Gotham Citybike instead - about a 1000 bux difference!

D - I started thinking about a folder. My 'stretch limo' SWB RWD 'bent bike concept is gonna have a 60 inch wheelbase - plus the pedals out front! Be nice to be able to fish out the chain from inside the frame, and halve the length.

My later 'oyster' concept bikes will have handlebars and seats that fold down. They won't fold in half with rigid partial fairings.
But they will seal shut against theft and weather. So long as the wheel hubs can only be accessed from inside, they could have quick-release monofork wheels for ease of changes on the road.
A full size cruiser that folds in the middle.
D: I almost wish I built my Cruzbike around a folder.
The thing is a beast to store.
D: there are trail bikes with tiny wheels.
Then 'real' bikes for 'real' roads. With real potholes.

The 'briefcase bikes' are pretty KISS, given that you will want a carry case anyway.

D: the folding 'bent bike pic is useful.
The diagonal packing scheme is pretty sensible.
Though the pic is of a long wheelbase, many aspects apply.
I suspect the front pedals could be on a pivot.
It'd be elegant to have it turn on the front wheel steering tube, but I imagine devilishly difficult.
'n of course, there will be a very long chain to stow somewhere.
A simple way to address steering would be to allow an ergonomic change of position,but to make that joint able to lie flat along the bike body. The seat rear, of course, comes off as a backpack.

Friday, January 14, 2011

nice primer on air resistance. stationary fan.

D: this chart is a bit misleading. Sure the air resistance does increase as the cube of speed.
But the other aspects of a bike matter still.
Linear so less and less a part of the total energy required.
But the chart exaggerates the use of a recumbent with fairing.
Particularly when weight is considered!
Let alone other practical considerations.

D: strangely I could not find a decent front profile pic of a bent online. At least not easily. So I took one of my Cruzbike.
Keep in mind my seat position is very upright for a bent.
But is sooo comfortable.
And I improve on the 'aero tuck' cross section in 'lazyboy' comfort!
I once tried to demonstrate the aero tuck to a co-worker. And promptly sprained my neck! WHY?!

But because the power to overcome rolling resistance is linear with speed, and the power consumed by air resistance is a cubic function with speed…by the time you get to 20+ MPH typically over 70% of the overall power you deliver to the pedals will be consumed by air drag!

For example, let's say that the tires rolling resistance power/wattage equals the aero drag power at 12 MPH, which is pretty typical. So at 12 MPH, we have one unit of power going to overcome rolling resistance (RR), and one unit of power going to overcome aero drag at let's say a total of 40 watts at 12 MPH. That would be 20 watts for aero drag and 20 watts for rolling resistance at 12 MPH.

When we double our speed to 24MPH, we now need 40 watts of power for RR because it is linear with speed, or 2 X 20 watts. Since the aero power is proportional to the cube of the speed, when we double our speed the aero drag component becomes (2^3) x20 watts, or 8 X 20 watts= 160 watts.

When we add the aero and RR components together at 24MPH, we now have 40 watts + 160 watts= 200 watts @ 24 MPH.

We only doubled our speed from 12 to 24 MPH, but the power required went up by a factor of 5 (40 to 200 watts) because of the dominance of the aero drag at higher speeds.

Mechanical chain drive for a fan for a stationary bike resistance unit.

D: I have a nifty 200 bux on sale magnetic stationary unit.
It works. I guess.
But it is just not the same as the wind whistling past me.
I'd say ruffling my hair but I just went bald LOL.
Anyway, there are plenty of electricity generator schemes online.
But I just want to run a long chain forward to an industrial fan.
Shouldn't be too hard to get a decent match to air resistance.
Plus it cools you.
And psychologically I MISS that air movement!!!

I'm just thinking thru wais required to DIY.
A long chain. I imagine a bent owner already has one for RWD.
A floor guide for components. 2x4s and nails should work, with some plywood.
An additional chainring or two.
An adapter to switch movement direction at the fan back.
Tear the guts out of the electric motor.
A busted unit will suffice, so long as the bearings are fine.
A coupla lengths of chain 'n rings to get that power there.
I imagine welding guides for all that to the stand on an industrial fan is simplest. Or bolting/strapping.

Hmm. Now I wanna build it...