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Old 03-27-2012, 07:20 PM   #1
apt13 OP
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Location: Athens, GA
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starting problems (again)

hi folks! some of you may remember me and my ultimately confusing mind bender from last year trying to get my bike to start reliably:

http://advrider.com/forums/showthread.php?t=682686

i thought i had fixed the issue as everything was fine at the end and the bike worked flawlessly on the random times i rode it through the winter. well now that spring has sprung and the bike is getting ridden more often, the exact same problem has started up again. i won't make you read the entire thing from last year, so i'll sum it up now and tell you what i've done so far.

the bike starts intermittently. sometimes i push the start button and the bike springs to life (with authority). other times i push the start button and i just get the click of the relay. more often i get the relay click. i can hit the button repeatedly and the bike will eventually start as nothing was wrong. the problem is i often will find myself stuck at the gas pump trying to start the bike for a couple minutes before it finally starts. i've basically become afraid to turn it off and full of anxiety the moment before i push the starter button to start her back up.

here is what i have and what i have done since last year's episode:

i've got the same odyssey battery as before (yes i know it's always the battery). the battery has been load tested at batteries plus and they say it is in perfect working order. (but yes i know that sometimes it is the battery anyway...it was an expensive battery and it pains me to think of having to buy another one.) the battery is only 2 years old.

i have brand new battery cables. both positive and negative.
i have a brand new valeo starter.
i have a brand new starter relay.
i have a brand new clutch switch at the handlebar.

all connections at the battery and starter have been cleaned. all connections at the relay have been cleaned.

battery is charged.
i get 12.95v on it.
when i flip the switch to run i get 12.5v
when i push the start button i get 12.4v when it does NOT start.
when i push the start button and it DOES start i get about 11.8v
at 2500-3000 RPM i get about 13.8v. at 3500 RPM i get 14+v.

when i click the start button, i ALWAYS hear the relay click.
when i pull the relay out and jump plugs 30 and 87, the starter ALWAYS spins.

down at the starter, i pulled the little black solenoid wire out. i stuck a lead up into the wire and grounded the other lead. with the key on i get 12.2v. when i push the start button i get 12.48v.

when i connect a jumper from the starter terminal to the solenoid the starter ALWAYS starts.

now when i put everything back together, the bike still starts randomly. when it does start it starts with authority as if nothing is wrong. but more often i just hear the click of the relay.

so what do you guys think? all these tests are basically what everyone told me to do in last years post, and now i have a better understanding of what everyone was saying. it seems all the tests yield positive results? am i just gonna get more "it's the battery" replies? haha.

i assume since the relay clicks every time i push the start button, that the button is fine? i have heard that opening the controls up isn't very fun.
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Old 03-28-2012, 01:15 AM   #2
batoutoflahonda
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It's the battery.

have u tried:

Next time it does it, try to get the fly wheel to turn a bit by putting it in gear and push it forward and aft. Then try to start it.
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Old 03-28-2012, 04:44 AM   #3
Martian
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"when i pull the relay out and jump plugs 30 and 87, the starter ALWAYS spins"

Can I presume you have replaced this relay with a known good one? If not, I would.
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Old 03-28-2012, 06:43 AM   #4
apt13 OP
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batoutoflahonda:
yes yes, "it's the battery" haha.
i just went out this morning. started the first time. got the relay click for the next few start tries. put it in gear and rolled it a little. then it started. i remember you mentioning this last year, can you remind me about what we are doing with the flywheel and why? also, since starting is random, how am i to tell that the flywheel turning is helping, or if it just starting randomly as usual?

Martian:
the relay is new as stated above, but i suppose i don't know if it is known "good" other than it being new. is there a way to tell without busting it open?

i suppose i can try and borrow a known working battery from someone and giving it a test for awhile. i just want to exhaust all the testing i can before dropping the money on a new battery.

thanks for the help folks.
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Old 03-28-2012, 06:51 AM   #5
boxerboy81
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If it doesn't start, jump it from a known good battery. If it works...
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Old 03-28-2012, 06:59 AM   #6
apt13 OP
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well i think i need longterm testing with a different battery, not just a jump. as sometimes the bike will start just fine 4-5 times in a row. other times it starts 1 out of 10 tries. so 1 jump to get it started isn't really going to tell me anything. because maybe it starts that once off the jump, but what if i was to jump it 3-4 more times and one of those times just clicks? haha. maybe i'm thinking too much into it.

i feel like i would need to put another battery in, use it for a few days or a week and see if i get the same results. if it starts every single time within that week, i suppose then i would know it's the battery?
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Old 03-28-2012, 07:20 AM   #7
R100RT Mark
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Has you/anyone thought that a worn or damaged flywheel ring-gear might be the problem? Is your “click” just a “click”, a “click with a dunh", i.e a jamming type of noise, or a “click and a whirr”?
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Old 03-28-2012, 07:30 AM   #8
apt13 OP
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the click is just the faint click of the starter relay. i can put my finger on the relay and feel it click when i push the button. there is no other noise.

as for the flywheel, the only mention of it is from batoutoflahonda above. he or someone else had me do that test last year but i don't think anything came out of it, and i'm not quite sure what it was testing for.
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Old 03-28-2012, 08:51 AM   #9
Martian
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Quote:
Originally Posted by apt13 View Post
Martian:
the relay is new as stated above, but i suppose i don't know if it is known "good" other than it being new. is there a way to tell without busting it open?



.....
I just keep coming back to the fact that with the jumper in place the bike cranks "every time". Is possible you have dirty contacts in the plug causing the relay not to work, but I'd get another relay and try it. I'm probably the only one who has had things bad out of the box, but it does happen. You can test it by probing the wire out of the relay and check it for voltage when you hit the switch.

Another possibility is a corroded ground connection somewhere in the circuit. You can read good voltage, but corrosion can prevent current flow. The only way to know for sure is to clean all the connections. If there is a splice in the wire, that's a good place to start.
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Old 03-28-2012, 08:56 AM   #10
apt13 OP
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a different new relay is definitely worth testing (and much cheaper than a new battery). i'll put it on the list of next round tests.
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Old 03-28-2012, 10:31 AM   #11
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It's NOT the battery

Well done tracing this one down this far! You've checked most of the troubleshooting items off the list, and now you're wondering if perhaps the trouble-maker has slipped through the cracks. Like, perhaps a closer look at the suspects is needed, as the culprit is hiding out in broad daylight sneering at you.

I'm guessing you haven't checked the suspect's hide-out yet.

Let me first say that I don't think it's the flywheel or the starter gear. Reason I say that is because no mention of the thunk or whirring of the starter motor when the problem occurs.

It's possible the relay is acting up, and it might be worth trying another, but this is already the second one (remember the original had the same problem) with the problem persisting.

So let's take a closer look at this system, and figure out a trouble-shooting program. List out the components: Battery, relay, starter button, starter and its solenoid, battery cables, wiring. Everything has been checked or replaced except for the last item.

Martian hit on it with connections. Wiring! That's what hasn't been crossed off the list! And the mention that voltage can show, but yet not flow enough current to be worth a damn is spot on!

And your tests tend to prove that out - that when the wiring was bypassed, everything worked normally.

Remember this wiring is 30 years old or more and corrosion can build up. The connections at the ends of the wires are crimped on and there's nothing to stop corrosion getting between the wires and that crimped-on connector. The only way to ensure an excellent connection is to solder them. Or just replace with a new harness. First ones I'd handle are the connections to the starter relay...
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Old 03-28-2012, 11:23 AM   #12
apt13 OP
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ok, i getcha,
all the main connections that are easily accessible i have pulled and checked and cleaned.

since i can jump the relay at the relay block and the starter always spins, can i assume that everything from the relay down to the starter/solenoid is good? or can some of those wires coming out of the relay block still be suspect?

the only thing i haven't opened up and checked and cleaned is the switch at the handlebar controls. i am under the impression this is a pain in the butt. is this something i should do to rule it out? i assumed that since it clicks every time i hit the button, and the run switch works fine, that it was good. i could obviously be wrong.

i will say that the overall wiring of the bike was a bit of a mess when i got it. i have cleaned up most of it in the headlight bucket with a new headlight harness and new turn signal harness. the only part of the wiring that is obviously in "bad shape" is the tail light harness. when i opened it up it was held together with painters tape. all i did there was clean it up and fix the crappy splices, but i didn't replace it with a new one.

the only other wiring i touched was the "warning buzzer" was unplugged and flopping around by the battery, so i just removed it all together.

also i had 2 brown wires not plugged into anything sticking out under the tank. from what i gathered they were for the horn(s) which were non existent. so i installed a horn and plugged one of them in and the horn works.

not sure if any of that would relate to my problem? but i obviously know nothing about this stuff, so i could be wrong! haha.

so if i was to start tracing the wiring to find something amiss, where should i start and what path should i follow?

thanks!
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Old 03-28-2012, 12:27 PM   #13
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I didn't read through all the comments but it sounds like you have a bad relay. Just because they click does not mean they are good. BTDT a Mcmillion times. The contact pads sometimes can't handle the electrical surge when the starter motor is coming up to speed. Try a good one. You can clean up the contact pads but for some reason they normally fail again in short order. Your better off getting a new relay.
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Old 03-28-2012, 12:46 PM   #14
apt13 OP
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i need to order a couple parts from somewhere anyway, maybe i'll throw an extra relay on top of it all. i was actually looking at them from the usual suspects last night and was curious about the wild price differences. can anyone clue me in? the last one i bought locally for $10 cash was a bosch, but i got his last one.

euromotoelectrics has a tyco(bosch) for 13.50
motorrad elektrik doesn't say what kind it is but it's $10
maxbmw has a bosch one for 27.75
bobs is also $27
and benchmark is $39

is there some kind of difference between the starter relays these places sell? just curious. obviously id rather spend 10 bucks than 40 if i end up buying a new one.
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Old 03-28-2012, 02:37 PM   #15
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Here’s my analysis of how a typical inertia starter motor system works. It might help you think through the problem.

The starter solenoid is simply a high-current relay that switches power to the starter motor.

The engine flywheel has a ring-gear around its circumference (essentially a “gear rack” wrapped around the flywheel).

The starter motor has a drive pinion (gear) at the “working” end of its shaft. This pinion is keyed to the shaft by a helically cut spiral in such a way that it can move along shaft’s axis yet can transmit the motor’s rotational power when it reaches the end of its travel. This is sometimes called a “bendix” assembly.

At rest, a lightweight spring holds the pinion away from the flywheel ring-gear. In operation, the pinion is made to mesh with the flywheel ring-gear.

In the first instant that the starter motor is energized, the starter motor spins freely (it has no load on it at this moment, and therefore spins freely under a low current draw). This imparts inertia to the drive pinion assembly and thereby causes it to accelerate and spiral along the motor shaft helix against the lightweight spring towards the flywheel. The pinion and ring-gear then mesh, the starter motor continues to turn (now slowly as it is under load, and therefore draws a very high current draw), and the engine cranks.

When the engine fires, the ring-gear turns the drive pinion faster than the starter which, aided by the lightweight spring, forces the drive pinion back along the helix to its "at rest/out-of-mesh" position.

If all you are getting is a “click” then it means the solenoid is being energized, in all or in part, but the motor is not being energized. Very poor “high tension” wiring or failed motor windings/brushes.

A “click” followed by a metallic “thunk” or “grind” suggests that the solenoid is being energized, and the motor is being energized, but the bendix is jamming as it tries to mesh with the ring-gear. Bad bendix or ring-gear.

A “click” followed by a “fast whirr” suggests that the solenoid is being energized, and the motor is being energized, but the bendix is either jammed in its normal “at rest” position, or some teeth are missing from the ring-gear and the pinion has nothing with which to mesh. Bad (dirty) bendix or worn pinon or worn ring-gear.

A “click” followed by a “slow whirr” suggests that the solenoid is being energized, and the motor is being energized but only in part and not sufficient to spin the bendix along the shaft's helix. Poor “high tension” wiring or failing motor windings/brushes.
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