practicle spedometer / tachometer ?

[kenwshmt-]

I don't want to junk up the bike, but has anyone come up with a simple effective way to measure distance traveled?

[Binch Shin]

There are two guys who uploaded their using experiences of the cycle computer in Korean community.

The first guy used a Glue-gun for attaching the magnetic on front wheel-hub. (he noticed there is a possibility to lose the magnetic.) Click here (you can understand without reading)
The model of computer was Topeak Comp 130.

Otherwise, the other man hung the magnetic to the air nozzle of the front wheel with a cable tie. (he noticed the magnetic could strike the sensor.)

[centerpunch]

Forget those old-technology units with magnets on the wheels. I bought a cheap Garmin GPS unit http://www.garmin.com/products/forerunner101/ and the optional bike mount, and I love it. Measures speed, distance, even draws your course.

[Binch Shin]

Very useful product. I have forgotten the old.
Thanks

[newcross]

I cannot forget those old-technology units with magnets on the wheels. They are still economically friendly.

Here is another photo. Some use epoxy to fix the magnet on wheel.

*Please copy the URL to the address box of your browser to access.
http://www.geocities.co.jp/Playtown-Den ... cy_con.jpg

source: Japanese blog
http://geocities.yahoo.co.jp/dr/view?member=sovtron2001

[kenwshmt-]

I got a $20 bell '15 function wireless' type, hoping to avoid the disaster waiting to happen in pic 3 of that first page.

good news.. it works..

bad news - the wireless sensor head is large and kinda backwards in its design for mounting on the wheel frame.
the sensor end is on the thin end of a tapered wedge shape.
the trick will be mounting it so that is within about 1/2 an inch of the magnet.
I'm working out how to attach it at the base of the fork, possibly on a small frame attached to the end of the wheel screw.

the magnet mounting is simple; using a nylon pull tie around the wheel hub, it goes through the plastic spoke mount on the magnet well enough.
It is tight, but i need to glue things down.

I will have to figure out what the multiplier is for the speedometer.

I would post pics, but i can never log in.

[kenwshmt-]

Ive made some progress.

My appologies for not having 'working' pic links, but guests cant post active links. put the . and / in the appropriate places.

here are some blurry pics of my efforts.

this is the sensor in about the place it needs to be to work correctly.

http://tinyurl.com/2mxuka

The sensor is intended to be 90 degrees off of what i have it, with the two rectangles and the rubber foot attached to the bike frame.
I am trying to find a way to attach a small shaft off the side of the bike frame, then i will be able to use nylon straps to attach the sensor as it was
designed to be, and not from the side which i dont want to do.
Something like a c-clamp, but i hadnt had time to research it yet.


Ive permanently solved the mounting the magnet on the hub. its removable and adjustable and if i break a wheel, changeable.
Stainless steel hose clamps, the ones with the screw.
I got a package of 2, one was too small, but two put end to end was perfect. #6 is the specification.

http://tinyurl.com/yrzj5e

http://tinyurl.com/33sx4e


ps. admin, feel free to reedit and make the pic links work as embeds

[newcross]

Ive made some progress.

My appologies for not having 'working' pic links, but guests cant post active links. put the . and / in the appropriate places.

Hi kenwshmt, I manage to see your photos. Nicely done! I'll try your method when I install cycle computer to my A-bike.

By the way, if you cannot register to this forum because of some system error, maybe it's good idea to e-mail Garry to sort out.

[kenwshmt-]

My apologies again for the strange links, I am incapable of logging on from anywhere, all I get is a blank page.

http://tinyurl.com/3bxdpo

The display mounted on the fold brace, at the point with the 'no foot' sticker.
The display is removable from the mount, which is just small enough to fit when the frame is fully closed.
It is on cable ties, and can move freely along the length of the pipe.

Why is the display on the Fold brace and not on the handlebars where it should be?
Insufficient range.
The sensor on a full size bike would be less than 2 feet from the readout.
On this bike it is only sensitive enough to receive at just past the press lock springs.

http://tinyurl.com/2shqcn

how the display looks from riding position, in spite of the camera making it look a mile away, it is a large readable display.

http://tinyurl.com/38qfj5

My handy work.
None of it is permanently attached to the bike, The L frame is a "2 1/2 inch by 2 1/2 inch" zink plated corner brace.
The 13 4 inch long cable ties; several are attached to each other to make longer loops, give some spring to
the frame. The 3 on the bike body above the splash guard are to keep the frame at the correct angle forward and back.
I have a large messy glob of white glue holding the magnet sensor to the metal frame, and a tie to the sensor in case the glue ever breaks.

The contraption has a pretty close tolerance, with the sensor being only 2 mm from the magnet, this is adjustable by the straps at the top end of the L frame.

http://tinyurl.com/3yth2o

After Ive field tested it, I will trim down the ties so that this thing won't have anything to chew on.

http://tinyurl.com/2nd6lb

The best picture of the lot.
None of the ties are closer than 4 mm from the tire, and that one is at the end of the L frame as a safety strap at the end of the sensor.


Next I have to try and get the speed indicated to be correct. The wheel diameter is set in MM, and the instructions come with a 24 inch setting, so I am going with 1/4 of that until I can fine tune it.

[kenwshmt-]

It works.

I trimmed down the tails, so it doesn't look like Frankensteins monster anymore.

I cant say as to the calibration yet, but I seem to cruise between 8-10 mph, with bursts to 14 mph, and a steady pace of 5 mph into a head wind.

Its not terribly inconvenient being attached to the cross bar, I can read the display fine there.

[kenwshmt-]

I did a long test.

My average, comfortable speed around town was about 7.3 mph.
up hills, into the wind, and basically moving and not falling over was 5 mph.
coasting down hills was 9-10 mph
steady, with the wind was 9 mph

I went 7 miles in 1 hour 15 minutes, with lots of lights, and a slow walk through a small shopping mall.