Author Topic: 500 Start Up Issues  (Read 1165 times)

Offline philward

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Re: 500 Start Up Issues
« Reply #15 on: March 16, 2021, 03:16:23 PM »
You could use the 750 as reference.

Meter for continuity down the positive starter lead across  to earth to give yourself reality check on numbers.
Why didn't I think of that! Just checked and I get same - ie, continuity - the live switching must 'shunt' the earth to the other side of the load (starter motor). This complicates it as why is the battery shorting itself out when I press starter button - solenoid engagement - bearing in mind that I've tried another solenoid? (its been on tandem charge - method to recover completely nacked battery - for 3 hours and still zero!)
Do I risk another shorted battery if I use the 750's battery!
« Last Edit: March 16, 2021, 03:18:36 PM by philward »
Current Bikes:-
Honda CB750K2 (1975)
Honda CB500K2 (12/1972)
Honda CR750 Replica (1972)
Honda CB350K0 (1969)
Kawasaki ZZR1100D3 (1995)
Kawasaki ZZR250 (1990) Project (Going on eBay ASAP)

Offline K2-K6

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Re: 500 Start Up Issues
« Reply #16 on: March 16, 2021, 03:19:58 PM »
I wouldn't put a battery on until the starter motor is physically checked, risks doing the same. 

IF it has taken the battery out it would be quite a chunky short.

Offline McCabe-Thiele (Ted)

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Re: 500 Start Up Issues
« Reply #17 on: March 16, 2021, 05:16:26 PM »
You could use the 750 as reference.

Meter for continuity down the positive starter lead across  to earth to give yourself reality check on numbers.
Why didn't I think of that! Just checked and I get same - ie, continuity - the live switching must 'shunt' the earth to the other side of the load (starter motor). This complicates it as why is the battery shorting itself out when I press starter button - solenoid engagement - bearing in mind that I've tried another solenoid? (its been on tandem charge - method to recover completely nacked battery - for 3 hours and still zero!)
Do I risk another shorted battery if I use the 750's battery!

Are you using the type of charger that will charge a completely flat battery - pulse chage technology some call it? Do you mean Tandem or in Series? Charging in Parallel is unlikely to recover a very flat battery IMHO- to my knowledge only Smart Chargers or Battery Chargers over 40 years old are likely to succeed on a completely drained battery. Just my opinion.
Honda CB500 K1 (new pit dug out ready)
Honda CB400 four super sport (first money pit)
Link to my full restoration http://www.sohc.co.uk/index.php/topic,23291.0.html

Offline philward

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Re: 500 Start Up Issues
« Reply #18 on: March 16, 2021, 05:30:14 PM »
I am grasping at straws Ted - I have been on Youtube and the parallel (or tandem) technique was suggested a few times - its an optimiser but have an old school charger as well (about 30 years old I guess) - which one do you suggest? May be a duff new battery and sparks from from when jump leads attached may be caused by inadequate contact between jump lead crocadile clip and bike leads (for starter motor current draw) - hence it went to zero as it was duff, not because of a short via solenoid (see previous post on a ground also showing on my fully working 750 starter lead.
Current Bikes:-
Honda CB750K2 (1975)
Honda CB500K2 (12/1972)
Honda CR750 Replica (1972)
Honda CB350K0 (1969)
Kawasaki ZZR1100D3 (1995)
Kawasaki ZZR250 (1990) Project (Going on eBay ASAP)

Offline Nurse Julie

  • 1977 CB550/4 Mongrel Brat. 1974 UK 500/4 K1. Honda CD250u.
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Re: 500 Start Up Issues
« Reply #19 on: March 16, 2021, 06:48:58 PM »
Forgot to add, as Ken suggested it looks like the starter motor is failing in some way. I'd look at that firstly, the car battery would probably have enough grunt and size to melt something if there's failure, that's in comparison to the bike battery.
Got to take the better half for her covid jab this afternoon, so maybe tomorrow before I get the starter motor out
I had my 1st Vaccination this morning Phil but I had to drive myself there 🙄🙄🙄🙄 Mrs Ward is a lucky lady having you Chauffeur her there 😁😁😁
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https://www.ebay.co.uk/sch/julies9731/m.html?item=165142672569&rt=nc&_trksid=p2047675.m3561.l2562

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Offline philward

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Re: 500 Start Up Issues
« Reply #20 on: March 18, 2021, 01:29:09 PM »
Well got it sorted - and it was a simple fault. As suggested by Ken, starter cable pinched between case and sprocket cover (not were I thought and was careful when installing - near alternator case via grommet) but were alternator and starter lead come out (in the 'u' in the crankcase thats specifically for the cable exit). This is were it exited originally (when I stripped the bike) but as the alternator lead and starter cable are a real tight fit through this point, I've re-routed it under the engine bolt (above sprocket cover chain guard/plastic rear chain guard) and up the rear of the frame tube. Not sure that this is the correct route but its the most smooth/non shaiffing route.
I still read a ground on the lead but its from the ground on the other side of the motor windings (which is shunted to the other side of the motor windings when the solenoid applies a live) - as per the test on my 750 curcuit - as opposed to the 'shorting' ground which applied a direct ground to the live when switched.
M&P are replacing Motobatt too!
Current Bikes:-
Honda CB750K2 (1975)
Honda CB500K2 (12/1972)
Honda CR750 Replica (1972)
Honda CB350K0 (1969)
Kawasaki ZZR1100D3 (1995)
Kawasaki ZZR250 (1990) Project (Going on eBay ASAP)

Offline K2-K6

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Re: 500 Start Up Issues
« Reply #21 on: March 18, 2021, 03:58:54 PM »
Good news you got to the bottom of it,  and good job you didn't put the other battery on there! Lucky with the motobatt too  :)

Offline McCabe-Thiele (Ted)

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Re: 500 Start Up Issues
« Reply #22 on: March 18, 2021, 05:43:16 PM »
I am grasping at straws Ted - I have been on Youtube and the parallel (or tandem) technique was suggested a few times - its an optimiser but have an old school charger as well (about 30 years old I guess) - which one do you suggest? May be a duff new battery and sparks from from when jump leads attached may be caused by inadequate contact between jump lead crocadile clip and bike leads (for starter motor current draw) - hence it went to zero as it was duff, not because of a short via solenoid (see previous post on a ground also showing on my fully working 750 starter lead.

I see you found the cause of the problem  - still annoying when you find its something realtively basic but job well done.Ted
« Last Edit: March 19, 2021, 01:15:52 AM by Macabethiele (Ted) »
Honda CB500 K1 (new pit dug out ready)
Honda CB400 four super sport (first money pit)
Link to my full restoration http://www.sohc.co.uk/index.php/topic,23291.0.html

 

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