Electrical problems

[tuxracer]

After a trouble free summer I'm now having electrical problems with my one and would be gratefull for any ideas you guys might have to sort it out.

I noticed back at the end of October the bike was getting lazy to start if it had not been used for a few days but once it had been started and had a run it fired up no problem. I thought that it was just the battery getting past it's best so ordered up a new battery. Put the new battery in and she fired up no problem and I thought that was it sorted. Went away for a couple of weeks holiday and decided to take the bike for a run when I came back, lights came on nice and bright pressed the starter, nothing but a click from the solenoid and a couple of half turns of the engine then nothing. Took the new battery out and got it swapped for another one just in case I had a dud. Charged the battery up put it in the bike and nothing but a click from the solenoid and a half hearted wheeze from the starter, then all the lights went out. Switched of and tried again, lights come on nice and bright, fuel pump primes and instruments do their pre-start check, press button and same thing, click, wheeze and lights out!!!!

Stripped the bodywork and checked all the earth connections to frame, and connections to starter motor and all are clean and tight. I thought I had found the problem when I checked the starter relay and found the connection to the positive battery feed badly corroded. I cleaned the connectors cables etc until they were all nice and shiny put everything back together, pressed the button and sure enough...................it's still the bloody same!!!!!!!!!!!!!!

Now I freely admit that I hate working with electrics and have no great knowledge of the subject but based on the fact that the battery has been replaced (twice), earths are ok and there is obviously power getting as far as the starter relay I'm thinking it could be the starter relay that is shot or if not that possibly the starter motor. What do you guys think and how would I go about testing to track down the fault?

Cheers

Tux

[rodge70]

you could try bridgeing the starter motor wires,thus connecting the starter motor direct to battery,use a heafty bit of wire across the 2 bolts or pliers,had a very simaler problem with my bp last week,turned out to be loose battery terminal,good luck

[DAVID THOMPSON]

the starter relay contacts get burnt and do not pass current to well
so starter gives a ho hum effort to crank the bike over
some starters get dirty on the copper pads where the brushes run
and give problems

dave

[tuxracer]

Based on that I'll have another look at it today and see if the starter works when I short out the pins on the relay. Assuming it is the relay are there any cheaper alternatives than the original MZ one as Grahams are quoting £46 for a replacement. The one on my bike is a Hitachi MS5D-361, I've tried finding a supplier online but not had much luck so far.

Thanks for the advice.

[LWS66]

The bridging of the starter cable terminals on the solenoid/relay is a quick way to see if thats the problem. I'd use a voltmeter and check the voltage at the battery when cranking to begin with just to see how much drop in voltage there was, but ultimately at the starter when cranking to see what type of voltage your getting there. If it is the solenoid you can either use oem and not have to do wiring mods, or source one from another brand of bike (the body of these things are pretty much the same, just the small wires connection is different), you'll probably have to cut the two small wires and splice in the connector from the old solenoid though. Either route will be about the same in cost I think.
If the solenoid trick does'nt help yet your getting full voltage to the starter then most likely the brushes or armature of the starter would be suspect. Ive yet to determine what brand of starter is installed on these bikes, either a Mitsuba or Nippon-Denso...clockwise or counter-clockwise rotation. There's a company (Rick's Motorsport Electrics, Inc.) here in the states that supplies drop-in brush plate repair kits for any of those two brands of starter. Dress up the armature and pop in a new brush plate kit and it would be good as new...and reatively cheap compared to a new starter or a specialist rebuild.

[johnny2tents]

Hi Tuxracer,

Modern batteries, 1000 twins, daylight running lights, cold weather. errrrrrrrrrrrm!

Was at a biker bash at Lochearnhead on Saturday night. The temperature got down to at least minus 5 deg C.

I had to jump start 5 of the 15 bikes from my van battery the next day.

After my starting problems on my '500 mile bike' after the Stafford Show, this is one subject area I could get paranoid about.

I routinely use an Optimate, but I will check the voltage drop when starting mine next time.

Then I shall use a slave car battery and check again. Then I will sit down with a beer and think about the results!

My old BMW K75S can be left outside under a cover for 6 months and will start up no problem whatever the weather.

Now that battery is physically nearly twice the size!

Cheers J2T

[DAVID THOMPSON]

the problem is a battery oem size is usually 1/4 the size it needs to be ....
to get bike started in cold weather
until i stopped riding in cold weather i always ran 2 battery's
dave

[millgreen]

Had the same problem with the track bike, changed the battery and soleniod but didn't help, found the fault in the relay, you can switch them around to check their all the same
Bill

[tuxracer]

I've not had another chance to look at my bike yet but as I've checked the earths and other connections, tried three different fully charged batteries, swapped all the relays round, and there is obviously power getting as far as the solenoid, my money is still on the solenoid being duff. However I've been wrong before so I'll let you know how things go!

Not to bothered just now as we had a fair bit of snow today and it is freezing hard, so not much chance of me being out............roll on the spring time

Cheers

[tuxracer]

Well I had a look at the bike again today and I seem to be back in business. I mate of mine lent me another battery (Yuasa) and I popped it in the bike and hey bloody presto.......... it fired first time and settled down to a nice steady idle. I then decided to give the original battery a try and again the dammed thing started on the button. Next up the first new gel battery, fired up but only ran for a few seconds and conked out. By the third attempt it would not turn the bike over. Tried the replacement gel battery that the supplier sent (it was charged last week) and it would hardly turn the bike over.

Starting to look like my problems were initialy caused by the corroded terminal on the starter soleniod and then I just got unlucky with the batteries. Its -4 degrees here tonight and I just tried the bike again ( its been outside all afternoon), started with no problem at all despite the ice! I'll leave it for a week and see if it fires up after that, if so I'll be a happy man.

[DAVID THOMPSON]

-4 C or -4F big difference i have started bikes at -27F and thats cold
a 1974 r90 s bmw with amsol synthetic in every thing and a car battery in the saddle bag
dave
amsoil engine oil toooo slick for the bikes with a wet clutch

http://www.amsoil.com/index.aspx?zo=1321567

they also stock a bunch of filter brands

[tuxracer]

-4 C or -4F big difference i have started bikes at -27F and thats cold
a 1974 r90 s bmw with amsol synthetic in every thing and a car battery in the saddle bag
dave
amsoil engine oil toooo slick for the bikes with a wet clutch

http://www.amsoil.com/index.aspx?zo=1321567

they also stock a bunch of filter brands

-4C - not as cold as BM weather but still enough to make the oil a bit thicker. When it's this cold you gotta be really keen to take the bike out if you dont need to. I've done it plenty in the past when I was young and stupid but my bloods way to thin for that lark these days

[LWS66]

Hey-Hey!!! Had my first "real" electrical problem yesterday on a group ride. About 4 hours into the ride we pulled into a gas station to take a quick break, one buddy and I swapped bikes, buddy went to try and start the MZ and....nothing! Lights on, fuel pump and guages went through their cycles, pushed button and nadda...no crank! Everyone started wiggling wires near the switch housings and flipping switches. I tried to console them and explained the starter repeat lock thing, relays and such...for a split second they looked at me like I was from Mars......but they quicly remembered that European bikes are quirky (they own and were riding them!) I removed the seat and rotated the relays and it cranked but would'nt fire now. So I knew it was a bad relay. Quickly found which one was for the starter, pulled the extra relay from the tool kit (this was the daylight relay I pulled out and smartly stuck in the pouch, it makes the lights come on and overrides the headlight switch..EPA government crap) and we were off! Now I'm trying to source a correct spec relay locally.....I already got one from an autoparts store, but I don't believe its exactly the same internally, at least according to deciphering the numbers, and may not last over the long haul. Searches on the internet are a dead end using the part number on the relay housing, anyone come up with an equivalent??

Also, I opened up the bad relay and discovered the fault. A small strip of copper split in half rendering the mechanical action inoperative......there was nothing burned out. Very clean inside.

[DAVID THOMPSON]

1000s i think
i will buy one some day and build a whole electrical system for it from scratch and a set of jap carbs

i hate to be the bearer of bad news but new bike electrical systems are making the efforts of Joe Lucas
look like he made good stuff....
dave