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Discussion Starter · #1 ·
so i Just recently bought a salvage striple and its been goin pretty smooth with a couple ajustments. i thought i got everything together but it still wont start. the gauges run when i turn the key but when i got to pull the clutch and hit the button the starter clicks and the check engine light flashes and nothing happens. i dont have the headlights connected because they were broke. ive got some after markets coming. if anyone has an idea of what else i could check that would be great.
 

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Just a shot in the dark, but hook the battery up to a trickle charger and let it charge some. The battery in the Striple is very weak. Hopefully that's all it is, but I'm afraid it very may well be the computer sensing an open circuit (your disconnected lights). The Striple and Daytona are really dependant on that puter. :(

Neanderthal
 

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Discussion Starter · #3 ·
ok ill try that out tonight or tomorrow... do you think the aftermarket ones will work or does it have to have stock?
 

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There is no current sensor for the lights. The lights themselves being disconnected doesn't matter, provided that the break in the circuit is AFTER the starter relay.

If the circuit is broken before the relay, however, (such as the headlight fuse being out) then the starter relay can click but no current will get to the starter solenoid. Check the 20A headlight/starter fuse as a good beginning point.
 

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Discussion Starter · #5 ·
ok, ill double check the fuses but last time i did they all looked to be good, i have it hooked up to a trickle charger too but the battery isnt holding a charge to well. is that from the weak battery or should i replace it since it may have been sitting for a while?

also the connectors for the tank were gone is i used some little single clamp things i got from the auto store. im not sure they may also be switched around.

may just end up being trial and error for a night or too.

any advice is welcom though! thanks!
 

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I surely wouldn't recommend trial and error! You can make some very costly errors messing with the wiring on a modern bike. Buy a copy of the shop manual. It's almost essential when trying to salvage a bike anyway, but especially for the wiring diagrams!

And yes, figure on replacing the battery. One that has sat for a long time without use is going to have sulfation on the plates, and will neither take a full charge nor deliver current very effectively. Depending on exactly what sort of click you are hearing when you press the starter button, a weak battery could actually be the MAIN problem.
 

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If it acts like a low battery stop immediately. Electronics are very sensitive to low voltage situations. The lower the voltage the higher the amps that will be drawn and this can burn up some electronics. This not only goes for this bike but every electronic device but due to the amperage a car and motorcycle battery can provides is very important with them. I have seen several engine management computers burned up from people repeatedly trying to start a bike with low voltage.
 

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Discussion Starter · #8 ·
ok, im going to get a new battery today, and i have only tried to start it a few times but with the trickle charger attached... i know i still have allot to learn and really appreciate all the help.

Thanks,
Ethan
 

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Discussion Starter · #9 ·
Where would you suggest getting a manual? i dont live close to any triumph dealers... is there a good site to get things like that off of?
 

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At this site we can't tell you how to buy bootleg photocopies; and all PDF downloads are pirated, by definition, since Triumph only offers a print version. All we can legitimately tell you here is how to buy the real thing. But most Triumph dealers will order it and ship it to you, if you can come to agreement on payment method. My nearest dealer is 110 miles away, but I made it a point to get to know them in person, so now they ship and bill me for most anything I need. For someone undertaking a project such as yours, this is a good thing to be able to do.

Also, if you want to find Triumph dealers with their own online stores, go to the Triumph Dealer Locator page, check the box that says Online Stores, then click Find.
 

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If it acts like a low battery stop immediately. Electronics are very sensitive to low voltage situations. The lower the voltage the higher the amps that will be drawn and this can burn up some electronics. {etc}
Electronic control systems are sensitive to low voltage conditions, which can indeed scramble data and thereby cause more problems than a person had to begin with. The problem is genuine, but the commonly heard "lower voltage, higher amps" explanation is an old wives' tale. As a noted stickler for accuracy, you should become more aware of Ohm's Law as it applies to DC circuits.

There can be duty cycle issues with various components overheating (like relay coils or the starter motor, if you try to crank it too long because it's turning over so slowly); but it's almost never due to "more current" actually being drawn, and especially not by the ECU itself. The ones used in these bikes will simply throw an error code and shut themselves down.
 

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The newer ECUs may be smart enough to shut themselves off. I doubt that they all do though. All computers require voltage regulation however and if the voltage drops they do try to compensate and can overheat and short.

I don't want to argue ohms law with you. You clearly have an understanding of it that I must not. Here is an ohms law calculator.

http://www.the12volt.com/ohm/page2.asp

Using I = P / E

If you have a 35 watt draw and your battery voltage is 12 volts than your current is approx. 3 amps. Same thing 35 watts now with a low battery 3 volts your amperage is approx. 12 amps.

I can tell you from experience that I have seen a lot of weird electrical failures from light bulbs to computers caused by low or bad batteries. Don't screw with them just charge them up test them if they fail replace them.
 

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I can tell you from experience that I have seen a lot of weird electrical failures from light bulbs to computers caused by low or bad batteries. Don't screw with them just charge them up test them if they fail replace them.
Sound advice. We are very much in agreement on that, even if for different reasons.

In hopes of promoting a better understanding of DC circuit principles, though, I hope you'll permit me to digress a little bit and explain in a little more detail why increased current is not the culprit.

Using I = P / E
If you have a 35 watt draw and your battery voltage is 12 volts than your current is approx. 3 amps. Same thing 35 watts now with a low battery 3 volts your amperage is approx. 12 amps.
This power formula is well established in science, but the flaw is in how you're applying it. The formula allows you to find the current drain if and only if you know both of the other variables, P and E. The thing is, you cannot assume that power consumption remains constant with changing voltage! It doesn't. In fact, it can't.

The rated power draw of any given device is the power it consumes only at the given supply voltage for which it is rated. As voltage decreases below the standard test condition, most electrical devices consume LESS current, and dissipate less power as a result.

This is because of Ohm's Law. In any device that presents a constant resistive load, current is always directly proportional to voltage:
I = E / R
The higher the applied voltage, the higher the current through the device; the lower the voltage, the lower the current. Most electrical components do present a fairly constant resistance to their voltage source.

The most notable exceptions are devices like transistors, which can be forced by their associated circuitry to try to maintain a constant current flow despite changing voltage; and tungsten light bulbs, whose resistance is not constant but varies with the filament temperature. Circuits involving these components can TRY to maintain a constant power drain with changing voltage, but only succeed within a fairly limited range of voltages. Real-world circuit resistances then take over to limit current as voltage drops further.

Take a headlight bulb for an example. To keep the starting numbers simple, let's say it's rated for 48 watts at 12 volts. When powered by that voltage, then, a nice round 4 amperes of current will flow through it, per the formula you quoted. Let's say it's a bright and very pure pure white light, and deduce a filament temperature around 6500K. At that temperature, by measuring the current and voltage, we know that the filament possesses three ohms resistance. (I=E/R, or 4amps = 12volts / 3ohms)

Now, let's let the battery gradually run down.

At 11 volts, the light gets just perceptibly dimmer, though most people would not yet notice much yellowing of the light. The very fact that there IS any change in the output tells us that the power of the bulb is decreasing, though--it's not a constant.

Interestingly, if you were to measure current through the filament, it has dropped less than the voltage has, because the cooling of the metal has allowed its resistance to decrease a little. The voltage has dropped just over 8 percent, but the current would have only dropped somewhere between 4 and 4.5% and be drawing about 3.83A. Plugging in the numbers, we now have the bulb drawing 42 watts (42=11V*3.83A) and the filament resistance is down to 2.87 ohms (R=E/I, or 2.87ohms = 11V / 3.83A) because its temperature is now below 6000K. And THAT is a direct result of the filament having LESS electrical power to convert to light energy.

That trend continues as the voltage falls. At 6 volts, the output of the bulb will be very visibly dimmer, and distinctly orange. The much cooler filament (in the mid-2000K range) will now have a much lower resistance... approximately 2.1 ohms. The current then is I=E/R, or 6/2.1 = 2.8amps. Not falling off nearly as fast as the voltage, due to the very non-linear resistance characteristics of tungsten with temperature, but still falling...not increasing. And the wattage is down to under 18, well under half what it was at the rated 12 volts.

Point being, the bulb CANNOT force itself to somehow draw the same power despite the voltage change. If it could, it would never start to get dim until the voltage dropped to zero*--and we all know that's not how it works. ;) The wattage consumed continually drops with decreasing voltage because the device doesn't have any way to force itself to somehow "pull" a correspondingly greater amount of current.

(And that's not even taking into account the fact that as the battery loses charge, its own internal resistance is increasing. That also ultimately limits how much current it can source as the voltage gets lower and lower.)

I used the light bulb example for the very reason that its resistance is not constant, and it CAN self-compensate somewhat for decreasing voltage--but most other electronic devices don't come anywhere close to that behavior. They actually do follow Ohm's Law more linearly, so that their current falls off in substantially direct proportion to a voltage decrease, not merely the square root of it like a tungsten filament does over part of its operating range. These are the sort of devices to which the ECU connects: relays, small lamps that have tiny current draws under worst-case conditions (and LEDs which stop conducting entirely when voltage becomes too low), fuel injectors, stepper motors, sensors, etc.; all devices whose current consumption drops as voltage does.

(*Remind me some time, in some other thread, to tell the story of driving a Triumph GT-6 automobile back from Birmingham, AL, to Warm Springs, GA, in the middle of the night with no alternator! Quite unrelated to [because it'd be completely impossible with!] modern EFI and electronic ignition systems, of course, but a beautiful illustration of power consumption decreasing as voltage does.)
 

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So, Diego, not only do you seem to have had every decent motorbike in history - or still do - but you've even had your hands on my dream car, a Triumph GT6 - our family neighbour took 5 years to do up his, going to enamelling under the bonnet, so I saw that beautiful thing at a highly impressionable time of my life! However, as I'm not a mechanic, but a pharmacist,I have to be realistic and admit that I'll probably never own a red GT6:eek:
 

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Sound advice. We are very much in agreement on that, even if for different reasons.

In hopes of promoting a better understanding of DC circuit principles, though, I hope you'll permit me to digress a little bit and explain in a little more detail why increased current is not the culprit.............
Very good examples and while I did understand that in principle about bulbs and other fixed resistor type devices. The problem is as you stated transistor type devices and specifically the built in power supply that the bike engine management computers have. Many of them will attempt to maintain the proper voltage right up to the point where they over heat. Some will over heat gracefully multiple times but will in fact weaken with every occurrence and eventually fail.
 
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