concerning multimeter

flanker850 · Mar 10, 2012

Im an electrical wuss. How do i use the multimeter to my benefit? I was thinking of putting the positive on the frame and touching different connections to follow the flow or lack of? my bike/paper weight will not show ANY outwards sign of electrical conduction. although blue brown at the ignition switch have power, i shocked my self accidently but it gave hope! anyway any multimeter thoughts wound be great, ths rob

Diablouph · Mar 10, 2012

Poking around in an electrical system if you don't know what you are doing is like poking around in a snake cage to see where the snake is. Sooner or later you are going to get bitten.

johnm · Mar 10, 2012

In the March 2012 edition of The Classic Motorcycle (photograph of a Brough Superior SS 80 on the cover) there is a short article on wiring faults which includes an introduction to using a multimeter.

L.A.B. · Mar 10, 2012

Use your browser to search for "use a multimeter", there's plenty of info.
Example:
http://www.wikihow.com/Use-a-Multimeter

concours · Mar 10, 2012

flanker850 said:
Im an electrical wuss. How do i use the multimeter to my benefit? I was thinking of putting the positive on the frame and touching different connections to follow the flow or lack of? my bike/paper weight will not show ANY outwards sign of electrical conduction. although blue brown at the ignition switch have power, i shocked my self accidently but it gave hope! anyway any multimeter thoughts wound be great, ths rob

If the bike is a paper weight, you didn't get shocked. 12VDC can't be felt. Do some searching, reading about BASIC electrical theory. Ohm's law. An analogy that seems to help people understand is comparing it to water, piping, tank, etc. Voltage equals pressure, amps equal flow rate, etc. Start there, and the rest will come so much easier.

http://www.autoshop101.com/forms/elec11.pdf

http://www.autozone.com/autozone/repair ... 3f80cb0bee

http://www.secondchancegarage.com/public/98.cfm

rvich · Mar 10, 2012

There are two settings on the meter that will come in handy. Ohms, which might look like a horseshoe, and DC voltage, which often has a V with flat lines (as opposed to a V with wavy lines for alternating current). The Ohms setting is used to detect conductivity or to ensure that there is a path for the electricy to flow (or the lack thereof). If your meter is digital it probably has a button you can push that will give an alarm tone with there is continuity. If you touch the two probes together on this setting the tone should sound. This is a nice feature when you are testing a length of wire or a circuit to see if electicity can flow through it. The multimeter has a battery that sends a small current through the circuit and if it makes it back the tone sounds. Other wise you need to watch the meter to see that it goes to near zero, on an analog this is usually at the right hand side so the needle actually jumps when you have a circuit. This should be done with the power to the circuit OFF.

The voltage setting should be used by touching the red probe to the frame or postive battery post (assuming the bike is still POS Earth) and the black probe to the wire or fitting that we want to check for voltage. Obviously the power needs to be on for this. The meter has enough internal resistance that you should not blow your fuse. If you do, something didn't go right.

Russ

flanker850 · Mar 12, 2012

thx for all the help!!! im learning about circuits and using the multi!!!! when i am in the dc mode and check for current i get @12v thoughout my connections!!! the ohms mostly settle down to around 1. so i think that is the current the meter supplies which i think means current is flowing, or maybe not. which seems to be the case, because i dont get anything to light up. ive gone through the connections and they seem to be ok. I think i just have to spend more time. im missing something here....

JimC · Mar 12, 2012

Flanker,

Don't use the Ω (ohms) function of your meter on a hot (battery connected) circuit. When checking for voltage use the V DC function of your meter. When checking for current use the amps function. Just remember you must have the probes connected between the battery and whatever load you want to test for current testing. If you want the overall current draw, disconnect the battery and connect the meter (amp function) probes, one to the battery and one to the wire you disconnected. Turning on ignition lights, horn, etc. should show an increase in current draw.

The water analogy is a good one. The battery being the pump in a closed ((recirculating) system. There has to be a way for the electricity to get back to the battery. Normally this is the chassis itself being used as a wire. This is referred to as ground.

powerdoc · Mar 12, 2012

Know the difference between a high impedance device (voltmeter) and low impedance device (ammeter). If you take a hot lead reading with the ammeter function to ground you are essentially shorting it to ground; it needs to be in series with the load not just hot to ground. Otherwise, just keep your fingers off metal things while it's running.

flanker850 · Mar 15, 2012

Thats for all the advice. I got the electrical system rocking. After a lot of electrical studies. The signals even work, who knows if i really need them. I wanted to bring the bike to stock and them modify as i go. Now its just tighten everything up and adjust the carb. I changed out the throttle cable and put the clip on the highest setting, I suppose it allows more petrol in. Is that where you guys put it??? PO had it on the lowest clip. cheers, Rob

pete.v · Mar 16, 2012

flanker850 said:
Now its just tighten everything up and adjust the carb. I changed out the throttle cable and put the clip on the highest setting, I suppose it allows more petrol in. Is that where you guys put it??? PO had it on the lowest clip. cheers, Rob

Wrong! The clip belongs in the place where it works properly. Lowest allows for richness, highest slot lean. This is for your mid range cruising around town and highway setting. Idle is a different animal and top end is the main jets.

Ride around in third gear at about 3000 to 4000 rpm. Shut it down and check the plug for a nice golden brown or any varience there of. As long as it is neither too black nor too white, the clip setting should be close. A plug adjustment can fine tune this color (hotter/cooler plug).

Your PO may have had it right and making such a large change in the clip position may be bad. Check your plug from the original clip position, then adjust as needed.

If you have idle issues, start another thread or at least seach the forum for pilot curcuit cleaning.

concerning multimeter

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