Topic: New Guy Needs some Encouragement 76 550F

[B. Alec]

Hey all, again, I'm a complete novice, but have done lots of reading!  Now I have lots of questions.

     So while I'm working on my very-far-from-starting '75 550F SS, I went out and bought a close-to-starting and VERY clean '76 550F for $400.  I got it home and it fired right up with a new battery, ran pretty rough, like the idle was set too low or something, and petered out when I stopped throttling.  Then it wouldn't fire up again. 

The guy I got it from said the P.O. had just driven it about a hundred miles and it had stopped running at the end of the trip, and had suggested maybe the alternator wasn't working.  I have an almost-brand-new battery in it now. I think I've narrowed it down to an electrical problem, because:

1. The plugs are new and after I kick the engine over(Starter doesn't seem to work at all), they all wet with gasoline.
2. The old plugs were on the black end of the spectrum.
3. The spark test against the cylinder head is a fail on all four plugs.
4. The compression test reads 130, 120, 130, 120.
5. The air filter and carbs seem to be at least serviceably clean.  So the electrical troubleshooting:

My understanding on this is you work backwards from the plugs: Plugs, plug wires, coils, condensers, points, battery.

I looked at the points and have heard contradictory things about whether or not they should spark when you pull them apart with a screwdriver.  The 1-4 points do have a small spark, while the 2-3 do not.  I tried to file and clean them, to no effect, so I'm waiting on a new set.  At the same time, I tried to statically adjust the timing, but one of the 3 plate screws is just not coming off, and is, in fact, practically stripped. 

My question is, what should I be doing now?  Are points bad if they don't spark when you do the screwdriver test?  Could the timing issue be the root of the not-starting?  If I replace the points and it doesn't help, am I looking at the coils?  I'm thinking it's unlikely that they're the problem, just since the bike did start for me recently.  And what to do about the plate screw?  I've put plenty of penetrating oil on it, to no effect.  It seems like an impact driver is the wrong tool, especially since the fitting is stripped.  I'm lost in the wilderness! 

I just want to go for a ride, man! 

Also, my ohmmeter has only settings for 1.5 and 9 volt battery testing.  Is there a tricky way to make it test my battery otherwise?

Thanks guys!

Ben

[gkw120649]

Did you think about changing the points, coils, and wires to DYNA components.

[TwoTired]

Multi-meters are pretty cheap $10-20.  And, if you suspect a charging issue, you're going to need one that will measure system voltages.

If your plugs aren't sparking, all carb cleaning won't get you going.  Plus, if they are wet with gas, they are metering fuel.  Maybe you will have to do the carbs.  But, get some reliable spark first.

What are the plug numbers you are using?

If, indeed, the bike won't charge the battery, even a brand new one will run down.  Especially with the headlight on.  Untill things get better, take out the head light fuse. 
Even a good bike won't run with a flat battery.  You can't make enough voltage to spark the plugs.  And, there isn't enough voltage to excite the alternator.  If there is enough to get it running, the alternator doesn't make enough power at idle to charge the battery, run the ignition, and excite the alternator.  And, if many diodes are shorted in the rectifier, the alternator windings will just drain the battery.

You need to know your battery still supplies 12 v.

Then, measure the voltage across the open points. Out to be within a volt or a volt and a half. of what the battery is supplying.

Remember, the plugs spark in pairs 1-4 and 2-3.  Both plugs have to be grounded to get a spark on either.  If you can make the points conduct when closed, you should get spark.  You should be able to set static timing, too.

If you can't get the plate screw off with an impact driver ($10).  Or, a tiny vise grips.  Then slot the head with a dremel tool and try again with the impact driver.  Get a new screw.

Hope this helps,

[Tim.]

Here's the best encouragement I can offer:  Bought my 1976 CB550F for $450 exactly 11 months ago.  A lot of time, sweat, frustration and $$$ later, and I'm enjoying it every day (putting a solid 75 miles a day on it running back and forth to the office).

Before and afters:

[Badboy]

TinTin,what is the exhaust on your bike? I bet it makes a good sound. I had a 57 Indian twin ,had mufflers shaped something like those,it had a very nice tone. Should have hung on to it.

[Tim.]

That's the stock Honda CB550F header and silencer.  It's actually pretty quiet.

[B. Alec]

Thanks for the input, guys.

1. How dirty would the carbs have to be to have the bike not start at all if gas is clearly getting to the plugs? 

2. Plugs are the manual-recommended NGK's: D7EA.

3. As far as measuring across the points, is this a matter of putting the positive multimeter wire on one side of the point and the negative on the other?  Electrical stuff is clearly my weakness at this point.

4. And looking at the Dyna ignitions...well, for $200+, if I can just learn how to do the points instead...

5. If the alternator is bad, would it show up in how the bike actually runs or does it just affect the battery charge? 

Thanks again!  A little direction helps a lot. 

Ben

PS. Tintin, that is a fine looking bike.  I'm curious about what it needed when you got it and what you had to do to get it going.

[B. Alec]

Hmm...Just figured out the easiest thing in the world...how to use the damned multimeter.   

So, my battery is only giving out about 9V.  I'm surprised, because I really haven't used it very much.  Is the drain really so high that trying to start a couple bikes maybe 30-40 times over the course of a month kills the battery? 

There's no way 9V will start my bike and all the troubleshooting I've done is meaningless!  Alright, time to pony up and buy a trickle charger.

One more thanks for reaching down and pulling a guy up!

[n9viw]

A trickle charger is good for maintenance, but I've had excellent luck with a charger I bought from Sears. It has provisions for 6 or 12V, regular or deep cycle batteries, and your choice of 2 or 10 amp charging rates (2 for bikes and mowers, 10 for cars), and a 60-amp starting circuit (CARS ONLY).
But the BEST thing about this charger is the float switch circuitry. It charges the battery at the rate you select, but when the battery nears the "top-off point", it drops to a trickle charge. When it senses the current draw pick up, it switches back to the regular charge rate until it drops off again. This will keep a battery "topped-up" without overcharging it- I've left a moto battery on it for a WEEK and had no noticeable detrimental effect.
I'd also check the coils, just for the knowledge. Disconnect the plugs on the small wires at the coils, and set your multimeter to measure resistance. You should see about 5 ohms across the two small wires of each coil. If you see less, the coils are either poorly matched to the bike, or may be dying/dead/shorted.
I agree with Lloyd's suggestion of an impact driver- the only way to get the silly pan crosshead screws out of these bikes. Replace them with stainless allen screws where you can- you can sometimes find screw sets on ebay for these bikes, I got a set of alloy screws- they don't rust, but they don't shine like stainless does. And no more stripped screws!
Head over to http://www.electrosport.com and look for the Fault Finding diagram in their Troubleshooting section. It's a flowchart in PDF format, so download it and print it, take it out to your bike, and follow it along. It will tell you what may be wrong with the charge circuit in your bike (if anything).
Good luck, let us know what you find!

[TwoTired]

The battery is rated to supply 12V@12A for one hour.  The bike's lighting, ignition, and charging circuit, draw about 7 to 10 amps.  Without recharging the battery, you could leave it switched on for about an hour and a half before the battery was dead.

The electric starter, however, draws 250-300 Amps.   3 or 4 minutes of cranking can flatten your battery.

A lead acid battery will also self discharge 5-10% per week.  This is why trickle chargers are needed when not recharged frequently through engine operation.

[B. Alec]

Excellent advice, guys!  I'll update my results shortly.

[B. Alec]

So, yet another cautionary tale about making assumptions.  Recharged battery made the thing fire up.  Adjusted the idle and am ready to go for a little ride!  The exhaust is just the tiniest bit smoky...probably normal for a bike with 40K on it? 

I am very excited, thanks for your help!

Ben

[oldbiker]

BATTERY CAPACITY.  If the battery is rated at 12 ampere-hour, that does NOT mean that it will give 12 amps for one hour as the manufacturer quote the capacity when taken over a period of 10 hours. They call it the 10 hour capacity rate. ie. It will give 1.2 amps for 10 hours or .12 amps for 100 hours but if you start to draw currents greater than 1.2 amps the effective capacity is lower than quoted.

[TwoTired]

BATTERY CAPACITY.  If the battery is rated at 12 ampere-hour, that does NOT mean that it will give 12 amps for one hour as the manufacturer quote the capacity when taken over a period of 10 hours. They call it the 10 hour capacity rate. ie. It will give 1.2 amps for 10 hours or .12 amps for 100 hours but if you start to draw currents greater than 1.2 amps the effective capacity is lower than quoted.

Yes, I know.  I was just spit-balling the numbers so as not to make B. Alec's head spin.   Battery specifications are even worse than you note.   A 12AH motorcycle battery is indeed rated at 1.2A for 10 hours.  However, there is no rating given for the 100 hour rate.   But, I would bet that, if given, it would be greater than .12 amps.  Deep cycle batteries will often give a 6, 20, and 100 hour rate.  And, the total power available will be different for each rate.  The larger the immediate demand, the lower the total capacity.

Perhaps this minutia will be of help to someone.