Topic: 1977 CB750 K7 Resto-mod, Knoxville

[AintNoEasyWay]

By the way, my new seat cover came in from the eBay seller you guys recommended. Can't wait to get home tonight & see what I can do with it.

[Prez1967]

Hey Prez, pretty rad to hear some about your build. Have you started a project thread yet? Would love to see it.

I wasn't aware Carpy had a lot that may help my build; I've bought from him before though, new fasteners to go around my carb boots. He seems like an awesome guy, so thanks for reminding me to check his site again for anything I might need. I am still on the lookout for new turn signals. Which ones did you go with & are you happy with the look?

Also, I'm thinking about just buying a new signal switch as well. Going to tear into it tonight & see if it's an easy fix like enwri mentions though.

http://forums.sohc4.net/index.php?topic=138009.0

Im really happy with the look of these turn signals.  I need to get the front end apart and remove the original ears for the factory units but for now, I dig it. 

Carpy has been great so far and I've only placed one order with him.  Everytime I call with a question I hope to get one of his desk guys but when he picks up the phone, hes more than willing to chat and answer my questions. 

I bought a spare 78 seat that I hope to have recovered locally to mimic the Giuliari style as I'd like to keep the factory two up seat for when the wife wants to come along.  Still debating if I should delete the rear fender all together and run my tag and brake light on the side or if I should cut it down and/or use a modified fender mount tailight/tag solution.  Already bought the side bracket/light so we'll see which way I'll go. 

The more I dig into my bike, the more I want to rip it completely apart and start from the frame.  Dont feel comfortable enough just yet tearing it down that far but only one way to learn right?

[enwri]

Fiddly little bits. And the fiddly bits tool kit. Centrepunch, dremel and 12 thou brass feeler gauge.

[AintNoEasyWay]

Finally got the bike ready for summer. Seat is recovered & good to go. I am having charging system issues though. I have to use the kick start every time in order to get the bike running. Can ride for about 45 minutes, only to turn off the battery & see that I still can't use the starter button to fire it up. I haven't tried testing the system yet. When I rev the engine the headlight becomes much brighter, otherwise it's pretty dim at all times (& there's no noticeable difference between hi & lo beam). I still haven't sorted out my turn signals either. I'm wondering if there's some relation between them not working & the charging system not working?

Photo of the bike in its current form is attached.

[Prez1967]

Lookin good brother!

[AintNoEasyWay]

Lookin good brother!

Thanks, Prez!

Sounds as though you're either not recharging, or not holding a charge. Most likely culprit is a bad battery. But, check all ground wires for clean, corrosion-free contact to bare metal, and any corrosion on the connectors between alternator and harness.

Thanks, calj. I'm hoping to dig into it tonight. I bought a new battery when I first got the bike last May, but the bike wasn't starting with the new battery (had to restore a lot of things). I didn't get the bike running until almost a year later, but I left the battery unplugged for all that time. The battery eventually went out during my attempts to get the bike running, so I recharged it a few times. The bike will then start ok from the starter button, so I assume the battery isn't able to hold a charge. Could it still be a battery problem despite that it's barely been used?

[enwri]

It's been a while since I've heard from you, assumed you've just been cruising around looking cool on the new ride.
It's been my experience that barely used batteries generally seem to die early.
If I've been stuck riding around in traffic, sitting on the brake with flashers on, it will eventually stop starting with the starter after about half an hour.
  Have found that I can hold it on slight grades on the front brake without the stoplight coming on (pressure switch not so sensitive to low pressure) and riding around in first or second gear between lights, as well as occasionally idling at about 2500 - 3000 for a minute or so, will keep it at about break even, ( Hot women stuck in cars beside you will think you're cool, I can tell by the looks I get, )  A quick run up the highway and back will get it up there again. Recently bought a gel or glass mat sealed battery, have had to knock the charge voltage down so as to not exceed 14.2-4, apparently they try to gas over that and can be damaged,  it gets up there pretty quickly after a bit of a run, was told wet batteries not as sensitive as you can just replace the water as it gasses off.
  There's probably something wrong with mine too, but I'm just happy there's a kickstart on it.
They're really hard to clutch start it in traffic, Le Mans style. ( it's almost 4 times as heavy as I am )
  The dyna made it go flat quicker, I'll probably put the points back on, only put it on to fix a misfire in the wet that wasn't actually anything to do with the ignition. (Wet overflow tubes, in slightly wrong position after messing about with them, took me a long time to work that out)

At least it starts first kick, first compression just about every time, holding the starter button at the same time I can usually kick it while sitting as well. Too easy.

You can barely notice the voltmeter if you don't actually look. It went from 12.9v with ignition off, To 12.28 with it on in seconds.

[AintNoEasyWay]

It's been a while since I've heard from you, assumed you've just been cruising around looking cool on the new ride.
It's been my experience that barely used batteries generally seem to die early.
If I've been stuck riding around in traffic, sitting on the brake with flashers on, it will eventually stop starting with the starter after about half an hour.
  Have found that I can hold it on slight grades on the front brake without the stoplight coming on (pressure switch not so sensitive to low pressure) and riding around in first or second gear between lights, as well as occasionally idling at about 2500 - 3000 for a minute or so, will keep it at about break even, ( Hot women stuck in cars beside you will think you're cool, I can tell by the looks I get, )  A quick run up the highway and back will get it up there again. Recently bought a gel or glass mat sealed battery, have had to knock the charge voltage down so as to not exceed 14.2-4, apparently they try to gas over that and can be damaged,  it gets up there pretty quickly after a bit of a run, was told wet batteries not as sensitive as you can just replace the water as it gasses off.
  There's probably something wrong with mine too, but I'm just happy there's a kickstart on it.
They're really hard to clutch start it in traffic, Le Mans style. ( it's almost 4 times as heavy as I am )
  The dyna made it go flat quicker, I'll probably put the points back on, only put it on to fix a misfire in the wet that wasn't actually anything to do with the ignition. (Wet overflow tubes, in slightly wrong position after messing about with them, took me a long time to work that out)

At least it starts first kick, first compression just about every time, holding the starter button at the same time I can usually kick it while sitting as well. Too easy.

You can barely notice the voltmeter if you don't actually look. It went from 12.9v with ignition off, To 12.28 with it on in seconds.

Hey enwri, always enjoy & appreciate your replies. Yes, I've been out riding a good bit. Definitely enjoy getting the looks . I did switch the bike over to a PAMCO electronic ignition with new high output coils (maybe this is sucking the life from my battery?). I didn't think this would cause trouble, but then again, I have no electrical knowledge, so that could be what I get for assuming.

My bike will start first kick, no issues there. Also, I'm also sitting on the bike when I kick it on. Never understood why some people don't do it this way as it feels very natural to me.

[AintNoEasyWay]

To answer your question: yes, despite the age or lack of use, it can go bad. Especially if you have over-discharged it. You need to test is with a meter with the key off. Then while idling, at 2, 3, 4 and 5,000 RPMs. Note the voltage at the battery.

You should see more than 12.8 from 3k up. If not, you have a charging/drain issue. If you are seeing it, then you have a storage issue. Enwri is right, AGMs are much better batteries and worth the price.

Rode the bike for a bit this evening, maybe about 30 minutes. Pulled back into the garage & started checking my lights & voltage. Headlight seems to remain about the same, like I said, whether on high or low. Only my right front signal stays on when bike is sitting at idle. If I'm riding the bike, I can sometimes get the signals to flash & the indicator buzzer to sound. Definitely wondering if that means these issues are all charging related.

I didn't try any more voltage readings other than just straight on the battery. But with bike off, I read 8.5 Vdc from the battery. My bike idles at about 1250, but for some reason the battery reads only 6.7 at idle. Up to 2k I get ~7.5, then up to 3k I get ~8.3. Does this make any sense?! At least this implies that battery is attempting to charge, correct? I wanted to check reading on the stator this evening, but the engine case was still pretty warm, & I had other things to get to this evening? Any recommendations for my next course of action tomorrow evening?

[enwri]

That's not right. did you get a new flasher switch? there is potential for a dead short inside it if it isn't wired in correctly, there are three terminals in the switch that all get connected together at once. other than that, there are far wiser people than I to help on here. last weekend I blew out my oil pressure sender switch by feeding it 12 volts from the field coil supply. oops, little bit of magic smoke from the starter motor cover as well. Who said that this 37 year old insulation goes brittle, bit of heat makes it nice and pliable.

[AintNoEasyWay]

Sounds good, calj. I may have to wait until the weekend if I need to charge through the night as I will be out of town until about 9 PM tomorrow. I'll be reading through this though & searching the forums to try to learn more about electrical problems. Will be back with an update by the end of the week. Thanks for your guidance.

[AintNoEasyWay]

That's not right. did you get a new flasher switch? there is potential for a dead short inside it if it isn't wired in correctly, there are three terminals in the switch that all get connected together at once. other than that, there are far wiser people than I to help on here. last weekend I blew out my oil pressure sender switch by feeding it 12 volts from the field coil supply. oops, little bit of magic smoke from the starter motor cover as well. Who said that this 37 year old insulation goes brittle, bit of heat makes it nice and pliable.

Hey enwri, haven't changed out the flasher switch yet; i was hoping that solving charging issues would get the lights working again, but now that I think about it, that probably won't happen since at least the right front indicator works (I should specify it doesn't flash when I turn on flasher switch right, except occasionally when I'm riding, it just comes on when I put the key in the ignition).

[enwri]

You're almost finished, I would concentrate on the charging too, it would be good to be able to isolate the flasher circuit to make sure it wasn't playing a part in the problem,  electricity does all sorts of weird stuff when it finds it's own way through compromised circuits, it is still likely that the flashers could come good when fed the proper voltage. From what I've seen on here, some bikes have indicator buzzers up near the headlight, is that where your noise is coming from? mine hasn't got one but the flasher unit under the sidecover makes a buzzing noise when the flasher switch started going bad. easiest place to start is check for obvious trapped or pinched wires, wrongly connected, or fitted parts, my example is the rectifier on mine had spun a bit and one of the heatsink fins was touching the regulator. It was supposed to be isolated from  the frame. Cant remember what made me search for a fault, but something must have seemed wrong. If nothing obvious, then you get the logic head on and go through the troubleshooting chart. Some people just know what those components do and what different faults appear as, I'm not one of those people, I rely on them to explain what to check. I've also been lucky not to have any major trouble either. Luckily the engineers made these thing fairly robust, and able to cope with me connecting the wrong bits together. Just remember "smoke and big splatty sparks are usually bad."

attached photo of rectifier short damage on regulator, in the middle of photo

[AintNoEasyWay]

Great, enwri. I didn't realize that some bikes make a buzzing sound for the signals if they're starting to go bad. I just heard the sound & after looking on the forums, found out that bikes made that sound when the signals are switched on. I'll have to look to see if the sound is coming from the front of the bike or behind the left side cover. Really wish I could start testing all this out tonight! Too bad work gets in the way of the bike sometimes.

[AintNoEasyWay]

Turns out that I never had any charging problems at all. After testing continuity across many of my wires, I decided to take my battery back to the store I bought it from & have it tested there. The battery I bought almost a year ago was faulty & they used my warranty to give me a new one.

Started up the bike with the starter button immediately yesterday with no hiccups whatsoever. Headlights are much brighter than before, turn signals all work except the rear left signal, which I’ll switch out tonight. Plus, now the gear indicator is actually bright enough to tell me when I’m in neutral. So this is what full voltage looks like? Very cool.

Anyway, I'm in business & now I can move on to phase 2. Dun dun… dun. Lots of polishing. Time to change out wheel & steering bearings. New swing arm bushings. New Godffery front brake disc & rear brake pads…

But mostly, a hell of a lot more riding.

[AintNoEasyWay]

Does anyone have advice or recommended links for polishing? I have a basic knowledge of how to start out. Maybe 120 grit & gradually work up to 600?, degreasing before each new grit & using a cross hatch pattern over the previous grit. I also have a bench grinder, so I'm able to use a buffing wheel.

[enwri]

Good to hear it's all come good.  Time to get the miles on it.
At the moment it's 11:20 pm.  9°c I'm 80 k's from home on a 175 k round trip.  and have just stopped to put on another shirt that I have normally wrapped around my tool kit in my bag.
Phone went off in my pocket, just came back in phone range. Saw your reply and am trying to get my hands working again.  This is cold for me.

Made it back, down the Gillies Range, perfect conditions, can see lights coming from around the corners, much warmer at the bottom. 263 tight corners, and 800 m elevation change in 19 km of road. You'd think that front brake would have used up all it's squeal, nope, plenty more left for waking up the neighbours.

[AintNoEasyWay]

Started up my bike after work today & have a new issue(s). Blue-ish smoke coming out of the exhaust & an oil leak coming from the front of the engine. You can see the leak slightly in the photos below. The leak comes from around the #2 exhaust flange & drips down onto my frame before forming a puddle below the engine.

What the hell?! I thought I had this thing in great condition. Would really appreciate tips on how to move forward from here. I've just started reading up on this, but it sounds like I could be in trouble. I shut off the bike & won't run it again until I know for sure what's going on, lest I create some bigger engine issue I'm not aware of. Thanks, guys.

[enwri]

That's a pain in the #$%, It will make a big difference whether it's coming from inside the cylinder or from the rubber plugs under the cam. Pull out the spark plug, or the exhaust header and look in the port, post that result, wet and oily or not, it's the difference between bad news about having to remove the engine, and even worse,,, having to remove the engine. I don't think you're going to be able to avoid it. You could If you get the frame cut kit installed before you try to fix it.
 Rubber discs are pretty easy, head gasket or cylinder damage isn't much harder, just a few "cough cough" more dollars..
This has happened many many times, there will be plenty of info here.

edit and afterthought.,

Mine was a bit smoky and had one wet oily cylinder before I pulled it apart, the rings were within tolerances but gummed up, (replaced them, std size, with a light hone.) Head gasket was leaking a little  due to I think a long dowel poking up too far, the only other things I replaced in the top end were the valve guide seals, rock hard and broken, gaskets, and O rings, cam chain and tens. No more smoke. No more oily cylinder. . 16000 k's later pulled the motor to fix the leaks from the pucks and re torque the head, ( bit late, but better late than never I suppose, wouldn't have at all if it hadn't leaked)
That's what the photo is, hasn't leaked in the 2000 k's since.

P.S. Think about getting the frame kit, it would make it much much less work..

I'm no Psychic, but I see this in your future...

[AintNoEasyWay]

Damn! Guess that motor will be coming out. Another forum member is stopping by possibly today to take a look with me in person. I don't have a way to do a compression test, but was thinking I should check compression before pulling the engine. I'll check the exhaust header & port first though, as you advise.

Hopefully I'll be back with an update later this evening. I'm going to repost the problem in the sohc bikes part of the forum to see if I get more ideas. As always, thanks a lot, enwri. You & your bike have been through a lot; hope my bike will be with me for the long haul too.

[enwri]

cb stains. not the knees, that's dirt.

[AintNoEasyWay]

Enwri, is this what you were talking about when you told me I'd be able to shine my shoes from my oil leak? 

[AintNoEasyWay]

reposting this from the SOHC bikes part of the forum:

Here's a look at the leak from my exhaust. It also seems like the leak from the engine case is getting worse because now it's leaking at the sides from some of the fins. As far as I can tell, the leak from the engine stops once I'm riding, but I pulled back in the garage & found this residue on my exhaust. Figured I should take a pic & show you guys. I changed my oil yesterday before riding.

I haven't found a motorcycle specific compressor that I can borrow, so I still haven't run any tests. But I've just begun plan to rebuild what I can of the engine despite my budget. Would be great if some of you could point further in the right direction. After reading some threads, here's what I've come up with:

APE studs from z1 enterprises, 77.31
Cometic head gasket from z1, 48.23
Cometic base gasket from z1, 12.52
Rings, (need to check my engine number) but 4into1.com has them for $40 a set
Valve stem seals, not sure the best kind to get?
Cam chain tensioner, roller, & guide set from Dynoman, 99.95
Tsubaki cam chain from z1, 32.51
Cylinder head rubber seals from z1, 3.38 each

Cylinder hone, not sure about prices from local shops or if this would be necessary?

This is assuming the valves are in okay condition & only need to be lapped. Does this seem like a thorough enough list for a top end rebuild?

[AintNoEasyWay]

Sounds good, calj. I've seen Mike around the forums & might contact him once I get into the engine this week. The engine is ready to be taken out, but I got cut short waiting on someone to help me take it out. I'll have my dad around to help me today, so hopefully we can get it out together.

That said, I still have some updates & a few more photos. I changed the oil Friday night & had just filled the tank last Tuesday. After changing the oil Friday, I rode the bike around the block & noticed it kept hiccuping when I gave it throttle. It died on me twice in the small trip around the neighborhood, but after letting it sit a couple minutes, it started up & held an idle long enough for me to get it back up the street. I opened the tank yesterday & there was barely any fuel left! I must be losing both oil & gas.

Also, when prepping to take out my engine yesterday, I drained all my new oil & it was a thick black, as if it had mixed with gasoline...

The photos below show the trouble areas around my engine. Of course I haven't taken off the head yet, but every exhaust valve appears to have the same weird, white coating over it. I assume because oil hasn't been getting to the valves properly?

What kind of mess have I gotten myself into? Stay tuned. Will be back later today with more updates & photos of inside the engine.

[Stev-o]

If gas mixed with oil, it would be very thin, not thick.
That white valve shows a very lean cond and needs to be addressed.