71' CB500 monoshock with no name...O2 sensor success!

Re: 71' CB500 monoshock with no name...Fenders finished

butzer489 said:

Looks slick dude. She's an eye catcher for sure.

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Thanks! Some "old" guys were looking at it this morning when I stopped for gas. They said some nice things and I asked if they had bikes and he points to a trailer behind his truck. All original CB750 chop from the 70's I wish I would have remembered some of the names of people that had worked on it...dang. Something about vader rims or similar? They were pretty cool 10 spoke in the front and 5 in the rear. Front end was round girder with disc brake, and rear swingarm was chrome and rear also had disc conversion. And next to that was a nice Triumph. They were headed to a swap meet down south of us. Nice guys!

On a side note: Either the headlight has too much draw, or I am not charging properly..or both. I ran it 2 days without any problems. Went to kick it over to leave the gas station and had to shutoff the headlight and kick 10 times....I normally need 1 kick to start, even from sitting a few days. So it's really time to sort that out. Ugh. Just got the news my car will be at the shop another week...so I REALLY need to get it figured out now! haha

Bike had these mags, but was a CB750 engine. Kicking myself for not taking a picture! Thought I would throw in the second pic with the girl to have a period correct chop pic too

Re: 71' CB500 monoshock with no name...Fenders finished

Those are invader wheels. Pretty cool.

Re: 71' CB500 monoshock with no name...Fenders finished

canyoncarver said:

Those are invader wheels. Pretty cool.

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There we go! I thought someone here would know. They were cool looking. The front disc was MAYBE 5 inches in diameter It had the coffin tank and seat like the first chop above. In a 70's mettalic orange paint job. Thanks for the info Canyoncarver!

Re: 71' CB500 monoshock with no name...electrical hiccup?

Now on to my "charging" issue. The issue is that it appears to check-out just fine! Yet when the headlight is turned on, even at higher RPM's the battery slowly drains and by slowly, I mean very slowly, but if I take a 40 mile ride, it might start getting too low and cutting spark out if I leave the headlight on. Just to be sure, here's some pics of me checking the electrical. First pic is of the 3 yellow wires. Nothing touches ground, so from what I know, that means all is OK. They all Ohm to 1.1ohms between eachother.

The other thing I was told to check was the Green and White wires. That Ohm's at 5.8 or so. I read anything from 4-8ohms is "good" So I feel like I can rule out the Stator as the problem correct?

Next up, I have a brand new reg/rec unit. I truly haven't checked this out and will do so today. Not really sure what to look for on this one, so I'll have to do some more research. If anyone has any numbers handy, I'll take them, I've been crazy busy as of recent, and with all my bikes down, and my car down...I have nothing that moves except this bike...which I'm charging when I get home, and when I get to work..haha. Thanks for anything in advance!!!

Re: 71' CB500 monoshock with no name...electrical hiccup?

Ohms is one way to look at the stator but there are other avenues that will give you the best info on if it is bad. Did you check the voltage output on the stator with the bike running through the rev range?

Re: 71' CB500 monoshock with no name...electrical hiccup?

danejurrous said:

Ohms is one way to look at the stator but there are other avenues that will give you the best info on if it is bad. Did you check the voltage output on the stator with the bike running through the rev range?

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Yeah, it would go to 13.5+ volts above 3000rpm (which is normal) but that's with the light off...then I hit the light and I can watch the numbers slowly go down. I did just notice that the new rec/rec needs 12V in to the black wire and I did NOT have that...so I just put 12V to it when the bike is switched into the ON position. I'll report back, but I'm assuming that failure on my part was at least SOME part of the problem

Re: 71' CB500 monoshock with no name...electrical hiccup?

It should go to well above 14 volts with the light on above 3K and almost 15 at redline. My GL runs at 14.4 all rpms with full old fashion lights.

Re: 71' CB500 monoshock with no name...electrical hiccup?

Maritime said:

It should go to well above 14 volts with the light on above 3K and almost 15 at redline. My GL runs at 14.4 all rpms with full old fashion lights.

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SH*T then I've got problems. I ran the 12V to the reg/rec and haven't had a chance to test it. Hopefully at my 2 o'clock break I can get out and putz around with a meter...thanks for the heads up Maritime!

Re: 71' CB500 monoshock with no name...electrical hiccup?

Use your meter and check battery before start, resting should be around 12.8 V, then fire it up and see what it is, should go to 13+ at idle which will run the bike and maybe break even, rev it and after 2500-3000 it should go over 14 and if you get past 15 you can ruin your battery so it should stop at under 15. If you don't get the increase it is your stator not putting out the required juice, if it goes past 15 you have a bad regulator. If it doesn't read right after starting your rectifier may not be converting from AC to DC

Re: 71' CB500 monoshock with no name...electrical hiccup?

Maritime said:

Use your meter and check battery before start, resting should be around 12.8 V, then fire it up and see what it is, should go to 13+ at idle which will run the bike and maybe break even, rev it and after 2500-3000 it should go over 14 and if you get past 15 you can ruin your battery so it should stop at under 15. If you don't get the increase it is your stator not putting out the required juice, if it goes past 15 you have a bad regulator. If it doesn't read right after starting your rectifier may not be converting from AC to DC

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Honda spec in the early 70s was 15.5V, so it may very well go up that high. Not so good for modern batteries, so it's an argument for eventually replacing it so you can get several years out of a battery instead of a couple.

Re: 71' CB500 monoshock with no name...electrical hiccup?

Rich Ard said:

Honda spec in the early 70s was 15.5V, so it may very well go up that high. Not so good for modern batteries, so it's an argument for eventually replacing it so you can get several years out of a battery instead of a couple.

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The funny thing is that I know all about charging systems from my stupid Aprilia RSV1000...I'm on my 5th stator on that beast because Denso effed up and made a 500W rotor instead of 370W...and Aprilia wants us to cough up $1250 bucks for a new rotor that they got for FREE from Denso because they screwed up. Anyways, I digress....for some reason my brain thought 13.5V was good enough...knowing that it's usually 14.3V or higher really ugh. It's been a hell of a month for me. Thanks for the kick to the head gents! I'll get you the news when I get on my break in 15 min!

Re: 71' CB500 monoshock with no name...electrical hiccup?

LOL We have all been there. I am fresh off replacing the alternator on a 2007 RAV4 and just did all those checks.

Re: 71' CB500 monoshock with no name...electrical hiccup?

Maritime said:

LOL We have all been there. I am fresh off replacing the alternator on a 2007 RAV4 and just did all those checks.

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Haha yep, stupid charging systems! Wait...without them we couldn't get far... haha.

Here's the results. I think the pictures speak for themselves. And my current thought is that there is something wrong with the battery. 14.5V at higher rpm. But when you let off that throttle, it dips right back down to 12V range with the headlight on. Somehow the battery can't handle that kind of draw...so I'm going to have it checked out. Borrowing a co-worker's car to get another one (should be warrantied....) Wish me luck.

Re: 71' CB500 monoshock with no name...electrical hiccup?

What the EF. Results "show" the battery is NOT the problem. Ugh. Forgive me for asking a stupid question...but can an "old" headlight draw more energy than a "NEW" headlight if they are both 55W or 35W etc.

Lastly, it should stay above 13V with the headlight even at idle don't you think? Should I be looking at some other output? I've verified that they all are considered "working" Stator (check) Regulator/rectifier..(check) and Battery... (check) I took out all unnecessary switches or connections too! Any other thoughts!? (I'll take anything not involving a sledge hammer please )

Re: 71' CB500 monoshock with no name...electrical hiccup?

You can "hot wire" the alternator to see if the regulator is acting up from burned/pitted points: jumper between the BLACK and WHITE wires at the regulator and ride for a while. This traps the field coil to full current to max out the alternator, and will not hurt it. It will also make the lights dim more at stopsigns, because the field load is not being dropped out at low speed.

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from

http://forums.sohc4.net/index.php?topic=65525.0

~kop

Re: 71' CB500 monoshock with no name...electrical hiccup?

kopcicle said:

from

http://forums.sohc4.net/index.php?topic=65525.0

~kop

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Do you mean the Points as in the ignition points? Under the front right engine cover on my CB500? I have brand new points, timing is dead on, and new condensers as well. Or are they saying the points being the connections on tthe reg/rec....because that is ALSO brand new solid version.

Thanks for the link though Kop.

Edit: looks like they are talking about the electromechanical regulator points?

I HATE to ask...but what about some sort of lower wattage headlight bulb...say HID style?

http://www.ddmtuning.com/Product-Categories/Motorcycle-HID-Kits-Lighting
and this to prolong life? eh?:
http://sohc4shop.com/catalog/product_info.php?cPath=23&products_id=46

Re: 71' CB500 monoshock with no name...electrical hiccup?

Yes HID , and even LED . Who knows , by the time you get around to searching it (Matt has already done some of the work) there may even be a viable led option .

And , yes the points in the regulator . Do a little searching and you'll find they are adjustable but a bit tricky .

~kop

Re: 71' CB500 monoshock with no name...electrical hiccup?

kopcicle said:

Yes HID , and even LED . Who knows , by the time you get around to searching it (Matt has already done some of the work) there may even be a viable led option .

And , yes the points in the regulator . Do a little searching and you'll find they are adjustable but a bit tricky .

~kop

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Well, I've eliminated that with this already, so that won't be necessary : http://4into1.com/ricks-motorsport-electrics-honda-rectifier-regulator-combo-cb350-cb400-cb500-cb550-cb750/

I'll keep searching. I don't want to pay $200 for an LED headlight...those bad boys are spendy! I enjoy the stock headlights looks actually.

Re: 71' CB500 monoshock with no name...electrical hiccup?

LED headlight on SOS.
12W draw with high beam on.

Cost me just under $100 after import from the UK because I get trade prices. ;D

Re: 71' CB500 monoshock with no name...electrical hiccup?

LED headlight on SOS.
12W draw with high beam on.

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That's pretty cool man. I like the look on yours. Do they make something that would fit into the stock old headlight bucket haha I really like the "old" look to mine.

Update: Last night when I got home I checked voltage = 13.2V and today coming in to work voltage = 13.2V So I feel like it's charging now! I do shut the light off at stop lights though : I've got a little LED volt display coming in from China...haha so that should allow me to relax a bit.

On to the "next" issue. At idle, the bike wants to race up slightly, and then practically die if I don't hold the throttle up a bit. I have a Gunson Colortune and at idle it is spot on, and just about rich. I haven't adjusted the valve clearances for a bit (almost have 300 miles on it as of today) and the last time I checked them was at 50 miles since I thought they might have seated by then. I did have the seats ground etc from a known guy in my parts. He does a lot of vintage tractors so his shop is pretty cool. I will also note that I just synchronized the carbs and it was idling fine when I did that...