Bike computer/No Trip Odo

[Guest]

Problem:

Trip odometer does not turn.. I have the gas guage which is also inaccurate so all I have is my reserve on my petcock to guage my fuel reliably. I put in a replacement cluster that had lower visible miles but the trip odometer is also broken on that guy. rather than crack open my existing one I figured bike computer for a trip odometer would be fine. However, I am still at ends on finding one that says it will read over 60MPH ... I don't go much past 85 so it is really a small issue.

Anyone have any experience on this approach?

Bike is 1980 GS750E 'Blue'

I have two spare clusters so I should in theory have enough parts that could make one work completely but I am just not up to the task. Speedometer and tach work but just no trip meter. Less someone is willing to offer to let me box ship my two spares to them to get them to cooperate I think I will just go with this approach instead ... if I can find one that will work for less than $30. I did see a person say they put magnets on there rotor toi get one to work so it ai't impossible.

Anyone...?

[Scotts]

Well I have an 86 550 es so this may not apply to you. Mine has been asphalt adjusted on the instrument cluster. Your parts may or may not have. On mine there is a reset button on the front. All I have to do is push it in. The rod got in a bind and was in between in and out. It only pushes a plastic lever. The trip meter would not turn while the rod was in a bind it was undecided whether it was in or out so it did nothing until I tweaked the bracket that the rod went through to line everything up.

Good luck to you.

Scott

[Kcwiro]

oh I tried the reset switch on it.. no go... I'm thinking I just got another bum speedometer cluster... but i fI can find a decent bike computer to mount up I won't have to worry about fixing the cluster at all.

If they are only $30 I'd say that is worth the saved tiem I can be working on something else =)

[billp]

I use sigma sport bicycle speedos on 2 of my bikes, they'll work till something like 165 mph according to them.
They also provide alot of useful info besides speed.
Aerostich has them but they can be found cheaper elswhere.


Bill

[Kcwiro]

what model?....

[robertob]

I use Sigmas also - I think I have a BC800 or something like that on my CB450. Works good as fast as I've ever had it.

[Kcwiro]

I grabbed a BC1606L one off fleabay for $32 overkill maybe.. but it has a backlight ^_^ *bling *Bling

[robertob]

I grabbed a BC1606L one off fleabay for $32 overkill maybe.. but it has a backlight ^_^ *bling *Bling

I wish mine had backlight. It can't be read at night, and since that bike doesn't have a speedo it means I'm guessing. Works OK, but you never know when a cop might be around.

[Kcwiro]

I had a quaetion as to how you mount the magnets on this ... I was htinking getting big instore magnet and putting it on the inside of the rotors but I am unsure.

[themess]

Some bike computer information that I copied from somewhere:

Bicycle computer on motorcycle

http://www.angelfire.com/ia/z/FZ1sigma.htm

lots of photos

http://mywebpages.comcast.net/billingsley/sigma.htm

http://www.rattlebars.com/vtx/sigma.html

Using a micro-light from Radio Shack to illuminate the computer at night.
Used an electric drill to test maximum speed of several brands of bike computers. Only Sigmas would go above 80 MPH.

Sigma Sport
Sigma BC800

Magnet

Super glue to brake rotor. Add another coat of super glue on top to protect from corrosion.

Or buy two Rare-Earth Super magnet (part # 64-1895) available at Radio Shack. Attach one to a rotor bolt with a tiny dab of super glue, and merely lay the second on top of the first. Experienced BMW owners say that the magnet will stay at any speed.

Battery life should be about two years or more.

Setting Wheel Circumference

Setting the Wheel Circumference, WS
....Measure the wheel circumference by tying a string around the front tire of the motorcycle (so that is loops through the spokes or perpendicular to the line of travel of the wheel). Sit on the bike and roll the string to the straight down position and mark the sport with a piece of tape on the floor or concrete. Then roll the bike forward until the string comes around to the down position again, keeping your weight down as much as possible, and mark this spot. You might make several runs for accuracy.

....Measure the distance between the tape marks. This will be the circumference of the front wheel, the value of which you need in mm. If in the US you are probably measuring in inches so you will need to convert by taking the number of inches times 25.4mm/inch. Example: 72 11/16th inches is equal to 72.7 inches. 72.7 inches time 25.4 equals 1845 mm. The 1845 is the value you will need to use as the WS value. This is just an example. You need to do your own measurement and calculation. The WS value for a stock FZ will probably be 1840 - 1850 mm, depending on the tire wear, inflation and weight of the rider.

....Another way to find the circumference is to use straight edges to measure the diameter and then take the diameter times 3.14. Follow the direction that come with the computer. I like to use two large carpenter squares held together to make a giant set of calipers.

....IMPORTANT: If you input, for example the 1845 mm value into the computer as the WS value, the computer will give you speed in kilometers per hour and distance in kilometers. If you are using English units you must convert by taking the mm value and divide it by 1.61, which is the number of kilometers in a mile. Thus in our example the value to input into the computer is 1845 divided by 1.61 or about 1145.

[robertob]

My bike has steel rims so I just used a decently large rare earth magnet. I tried a smaller one but it kept moving around and would sometimes flip around to the side of the rim where the pickup couldn't read it.

[Kcwiro]

Just got back to this thread... great guide themess I will put that to good use. I was always curious to figure out how these guys got their readings. I thought the sensor would have to be placed in the middle or something.. I had one on my pedal bike as a paperboy 'yes I did a paper route as a teen' anyway I had to be specific else it was totally off.

Will put informstion to use for sure.. again thanks for the good info.

[Ed Vrolijk]

Hi Kcwiro,
I use the Sigma also and works fine. If interested i can post you a picture of how the magnet is attached,
Ed

[themess]

I'm interested in a photo. I have a Sigma sitting around, waiting to install it.

[Ed Vrolijk]

I will try to make a picture tonight, and will post it tomorrow.
Ed