Bad Voltage Regulator

[Lifter]

Hello Gang!

Today while on my way to work, I experienced periods where my bike was stumbling.

I pulled over and it stalled. After a rough resart, I was able to limp it back home while my bike had more studdering periods.

I stopped into my local bike shop and they used a multimeter on battery. When I opened the throttle, the battery voltage dropped some.

They then used the multimeter on the contacts for the regulator and diagnosed it as vaulty.

Also, I have recently had a hard time while starting having to turn the engine over long time or multiple times to get it started. I just assumed that the battery was cheap..

I have a regulator on order but I thought that I would ask the group if this sounds like that likely fix or should I save time and money trying something different.

Thanks again in advance!

Brad

[blaine]

Sounds like regulator to me!!! :)

[Vegas Street Rider]

Ditto on the regulator.

[spldart]

I had one fail on me. First symptom was dim lights, slow blinkers and eventually it would crank slowly and not start. It ran just fine and with good power with a push start. (still dim lights though)
Replaced regulator and I'm fixed.
Testing charge system is very easy.
Put your meter on volts.
Good battery at rest = high 12's
Good battery with good charging system engine at 2k rpm. Mid 13 volt range
Good charge battery at 2k rpm with bad regulator. Low to mid 12 volt range.
Bad charge system and depleted battery will be low 12's or lower. Lower will not crank the bike to start.
If you need bad battery advice I can help there too.
Meters are cheap.
Trust me on the advice... There is a little various from bike to bike but it should be close enough.

[Vegas Street Rider]

Thanks Spldart. We all learned a lot. Off topic, how did things turn out after your accident?

[spldart]

After speaking with my attorney I can say I'm doing good. Bike isn't what it was even after all the money to repair and apparently my claim is going to suit.
Don't wanna say to much.

[Lifter]

Thanks for the help gents!.. Sorry to hear about the accident

The bike is new to me this month. I can't say I observed any dimming but it has been hard starting from the beginning. It might be they were always dim/slow. I found the headlight dim but had no frame of reference. My blinker indicator has been working intermittently but I hadn't started to diagnose that yet...

I don't have a tach so I did my best to get the test numbers you asked for.

Here is what I tried

Before I started bike: 12.7
After start while idle: high 13
Rev half way : mid 13
Idle after that: climbs over 14
Turn off: back to high 12

I'm going to take these few days for some maintenance and pull and clean carb tonight.

I figured I would have to do some repairs this spring so im looking forward to having a bullet proof smooth running commuter! :ride:

[spldart]

"Before I started bike: 12.7
After start while idle: high 13
Rev half way : mid 13
Idle after that: climbs over 14
Turn off: back to high 12"

Your charging system is working. Maybe not perfect but it is definitely working.
I'll guess it always turns over for you... jerp jerp jerp... always the same. Just hard to start.
Carb is the way to go.
And check your valve clearances.

Sorry! One more thing. Pull the spark plug and if you can take a picture of it and post it here. We wanna see the
end that make the fire. Electrodes. If it's a brand new plug then nevermind. But if it's been in there firing with the
problem we may be able to 'read' it for a lean or rich condition. ;)

[spldart]

Oh... And you did good on the numbers ;)

And if you do get the plug out and post it or not post it but wanna try to read it yourself....
Google 'how to read spark plug' and look for pics till you find one with lots of pics of different conditions and what they mean.
Good is a light tan on a used plug.
A new plug is very hard to read. Need to get some hours on it first.

[Lifter]

Thank you for the quick response and encouragement lol

At first I thought it was a fuel supply problem and I've been meaning to clean carb.. Just too busy riding

Pulled the carb out but had trouble with screws that hold on float bowl. Going to try again tomorrow with bigger screwdriver. For now I have it filled up with seafoam to soak for night..

Have pic attached of plug :)

Any tips in taking off the generator cover cap?!? Took a pic of mine..

[spldart]

Plug looks a tad off but ok.
Before you strip a screw I suggest you put a good #2 bit in the head of the screw then give a solid
rap with a small tool or a tiny hammer. It can make it a touch easier to back out a stubborn screw.
As to the generator cover there is a service manual linked on this forum somewhere. Download and read up.
Be careful about stripping anything. There are lots of tricks to preventing that or dealing with something that is starting to get stripped so if your in a corner then post and wait for response.
I'm about to nod off so good luck. I'll stop by the forum tomorrow.

[blaine]

A big washer & vice grips work well to remove cover. :)

[spldart]

A big washer & vice grips work well to remove cover. :)

Oh kewl! I just learned something :tup:

[Lifter]

OK so even with a vice a good screw driver and some help, knew of my screws is looking screwed...

Any advice on this one?

I know I was warned about this.... :cry:

[spldart]

At this point I think my favorite option would be to use a dremel with a small cut off wheel and slice a big slot across the screw head to get a flat blade to fit the screw.

Either that or use a socket extension and repeated very careful hammer blows to flatten the screw head out a bit then knock a #2 philips multi-bit into the mashed up head and try one more time.

Second option requires great care as you can do alot of damage to the body of the carb. I have personally used
this option numerous times. Usually case screws.

Both options remember to soak the whole problem in wd40.

[spldart]

Failing those options you have to drill through the screw head till it comes off it's own threaded shaft.
Very carefully. The screw is hard and will take a little time and effort. The body of the carb is very soft
so if you go to far your again gonna mangle the carb. Once the screw head comes off then so does
the bowl. More wd40 and take vise grips to the shaft of the bad screw and back it out.
Obviously you will need a replacement screw, variable speed drill, appropriate drill bit... maybe 1/4 and
again.... lots of wd40 on the area being drilled and the bit.
It might seem counter intuitive to a novice about spraying a light penetraiting oil on an area being drilled but what it does is keep the cutting edge of a bit from overheating destroying it.

[wacio]

Please go thru this video - you'll find this info indispensable.
https://www.youtube.com/watch?v=-mAba_NauXw

[wacio]

This is also quite good product for removing damaged screws.
http://www.amazon.com/Engineer-PZ-58-Screw-Pliers-GT/dp/B002L6HJAA?ie=UTF8&psc=1&redirect=true&ref_=ox_sc_act_title_1&smid=A1PN7KJE62VZLB
https://www.youtube.com/watch?v=BOtyXTG-PX4

[alantf]

One of the reasons that the screws get buggered up is that they are very likely to be posidriv, not phillips. The posidriv is not as pointed as the phillips, so won't go into the slot as far, thus shredding the slot. If you can't get hold of a pozidriv screwdriver, a temporary fix is to grind a couple of centimeters off the end of a phillips screwdriver. Not perfect, but better than just using the phillips screwdriver as it is. I have a set of different types/sizes of screwdriver heads that fit into a handle, so that I can try each head in turn, until I find one that fits perfectly.

[Lifter]

Hello

So the carb is clean and im just installing the jets.

I have a 120 and a 525 and im not sure which goes where...

[spldart]

Our service manual of blessed knowledge page 104 and 105 didn't help?

[spldart]

iirc the jet with the biggest hole centers over the same opening that the needle slides down ;) It's your main. That's where your horsepower comes from.
You'll have to pardon me as I am :coffee:
Please feel frree to correct anyone.

[Lifter]

Hello Folks!!!

Ok so i have cleaned out the carb and put it back together. The bike starts well and i took it for a spin. This lasted about 5 minutes and then same symptoms of bike studdering and stalling.

I got the new Regulator in and installed it. After starting bike up i couldn't even get it warmed up and out of parking lot until these same symptoms started to pop up.

I parked the bike and am going to adjust valves tonight.

DO you think that this can even be the issue at this point?!

Thank you all SO much for the assistance on this and advise: Im sure getting a lot of Bike Mechanics experience. :P

Ill start a new thread after i adjust valves if the problem still isn't fixed.

[wacio]

Things to check:


- disconnect from the carb hose going from tank to and put some container under it. Get petcock on prime for 15 - 20 seconds. You should get good consistent fuel flow. Try if bike runs OK when on prime.
- make sure that cable going to spark plug from coil doesn't rest on cylinder head. Mine was melted almost to conductor. It might be shorting ignition when bike is hot. Zip tie to frame so it is spaced from head.

[spldart]

started and ran well for 5 minutes after cleaning carb and checking a plug that was decent.
Is the fuel in the tank old?
Is there rust in the tank?
You might have to pull the petcock to check the fuel screens. One may have dislodged.
If crap in tank or dirty fuel you may need to drain tank, carb bowl to get the crud out.
Wish I was there. Meh.
And lastly.
You may need a timing light. Not to time but to check that it's firing regular when it's acting up.
You should see rythmic strobes from the light that you can see increase/decrease with revs.
I have seen a CDI modules and ignition coils go thermal intermittent.

Still. I'm guessing from miles away :(

[spldart]

Remember. It's air, fuel, spark, compression and timing.
I doubt your timing shifted or you cam chain skipped in the 5 minute test.
I doubt your compression was lost in a 5 minute test unless you ran with no oil.
So something is interfering with air (air filter) fuel (bad or clogged) and spark (electrical)

[Lifter]

Things to check:


- disconnect from the carb hose going from tank to and put some container under it. Get petcock on prime for 15 - 20 seconds. You should get good consistent fuel flow. Try if bike runs OK when on prime.
- make sure that cable going to spark plug from coil doesn't rest on cylinder head. Mine was melted almost to conductor. It might be shorting ignition when bike is hot. Zip tie to frame so it is spaced from head.
These things checked out. Thanks!

[Lifter]

Today i finished adjusting the valves, put the tank back on and took it for a test ride on Prime. It ran for 3 KM then began studdering or stumbling again. After doing this 2 or 3 times i got a backfire and eventual stall.

After walking it back home, i drained a bunch of gas and pulled petcock. screens looked clean. As far as i can see in the tank, i don't see any rust at all. Just a nice consistent light grey paint.

I cleaned out air filter and checked for obstructions.

I feel like at this point i may be reaching the limit of my abilities on this repair... Maybe its time to give up and bring it into a shop? But i sure am getting a lot of practice!

Any other intermediate level troubleshooting on this?

Thanks as always!

[spldart]

O_o Wowzers. At this point I'd be thinking electrical but that is getting a bit more involved.
This problem has sure put you through the ringer :(

[blaine]

Have you tested electrical output since you put on new regulator on.........This way you can rule out stator.....I have a feeling it is the culprit.

[Lifter]

Have you tested electrical output since you put on new regulator on.........This way you can rule out stator.....I have a feeling it is the culprit.
I have tied to troubleshoot the Voltage Regulator by testing the Battery Voltage before and after my two test rides. Everything looks good (High 12s consistently)

Is there a better way to check electrical Output?

My starter has been a little buggy... sometimes i have to role the bike a few feet before i can get it to turn over. But eventually i always get it to turn over. I figure that a Starter Replacement is in my future as well..

[blaine]

Should read 12.4 to 12.6 before start & around 13 volts at idle & up to a max of 14.6 when reved up......Many videos on Utube on testing. :)

[Lifter]

Hey There,

I gave up and brought my bike into the Garage.

It looks like they recommend a top end rebuild.

I started a new thread here:

http://www.gz250bike.com/forum/showthread.php?p=86129#post86129

Thank you all so much for the help with this!!

I have learned TONS!