your torch quit ? good golly man i thought you were a computer guy, quit using plumbers tools, no wonder your having a hard time
atf is automatic transmission fluid, a quart is cheaper than cable lube, follow up with motor oil and those cables are lubed for a long long time
somebody you know needs some atf anyhow
once you get the carbs off, put plastic bags over the intakes, plugup any holes
push it outside and give it a bath, wash out the airbox and theres no need to remove it
keep the coils tci and regulator dry, and the motor sealed up and engine cleaner and garden hose it up
thats the first thing i do to a fixer upper

Make a 70% Solution of DAWN Dish Washing Soap and Grease Cutter.
Spray Bottle.
Spray the whole Bike and hit the nooks and crannies.
Let the Dawn work.
Keep spraying it on the heavy soil.
Rinse.
Re-apply a 2nd coat of Dawn ...
Keep it moist and spray it directly on oil and grease.
15 Minutes
Rinse.

You should have a clean bike to work on now.

Didn't get to working on fuses. Will tackle that tomorrow, I suppose.

Plumber's tools. Ha! Well, it's working well now. I've never been any good at soldering. There's something about it I just don't seem to "get". No good at welding either, though I'm GREAT with a cutting torch. Go figure.

I'll work on that motor oil + hanging cable trick. Cables definitely need to come off this bike.

Pulling the air box is mostly an academic exercise, since I may want to replace or remove it at some point. I will pull the carbs and give the rest a bath, though. I'll just pull (or bag) anything electronic first. It's all disconnected already anyway.

Rick, 70% solution? 70/30 Dawn and engine cleaner? 50/50 dawn+cleaner and then THAT in 70/30 mix with water? I have both (and distilled, filtered, and tap water)... and a hose.

Funny thing is, having had the air gun applied to it, plus some plain old wet shop towels, the 750's frame and engine actually look a little better than the 650! Go figure...

Thanks for the advice, guys. Time (and funds) permitting, I may just have this thing operational by the end of the summer! I've been telling my wife "next Spring" though, since she thinks I'm going to spend a fortune fixing it. ;p

Sorry Rhys, I have never been able to get my airbox out of the frame without pulling the engine. I've broken one trying.

Robert wrote:

Sorry Rhys, I have never been able to get my airbox out of the frame without pulling the engine. I've broken one trying.

Well, crap. At least I know NOW, before breaking it myself, so thanks. :)

So how much trouble is re-jetting carbs? Having taken a good look at the pod filters on the 650 and the air box on the 750, I'd kinda like to stick pods on the 750, but I know close to zilch about the way carbs work. Is there a formula one can use involving air flow through the filter, size of the cylinders, etc. to choose the right jets, and then use the mixture screw to tune it, or...?

I'm out of my depth with the carbs, mainly because I don't know any of the *theory* of how they work, other than that they use the vacuum of the engine to suck varying amounts of fuel and air through the jets, mixing both and send them into the engine through the intake valves. I also have a vague understanding that "pilot" jets essentially determine the idle mixture and the "main" jets determine WOT mixture. Jets are the "coarse" adjustment and the mixture screws are the "fine" adjustment. The carbs also need to be closely synced so that one is not providing a significantly different fuel/air volume than the rest (so the individual cylinders contribute close to equal power).

Is that about right? Way off base? Good link to learn theory? I know there are several howtos for cleaning and rebuilding carbs on here that I intend to read, but do they go into the theory as well, or just the "remove this, tighten this, read plugs" part of it? One can't assume that I have chosen the jets correctly.

"pilot" jets essentially determine the idle mixture and the "main" jets determine WOT mixture. Jets are the "coarse" adjustment and the mixture screws are the "fine" adjustment.
50% credit for that one, WOT is all on the main jet size on these carbs
overall 80%, could have got 95% but you left out midrange (needle position)
next semester you'll do needle taper and slide cut-away
keep up the good work

I'm not going to stop you if you want to go the pods route but if you are not that well versed with carbs, I'd stick with stock until you get some experience on something a little cheaper in terms of parts.

Robert wrote:

I'm not going to stop you if you want to go the pods route but if you are not that well versed with carbs, I'd stick with stock until you get some experience on something a little cheaper in terms of parts.

Well, I tend to switch between long-term and short-term planning without warning, and given that I'd have to either drop the engine or destroy the air box to get it out, it's likely to stay for the near future.

Also, I have a spare carb rack for the 650, so my plan was to familiarize myself using those, then work on the 750 (since I can't break what doesn't run). Also, the Ninja and CBR not mentioned in my .sig are carbureted, so at the risk of breaking working bikes, I can always pull those off for additional reference material.

I figure that as long as I don't bend, break, shear, twist, or tear anything, the worst I can do is foul plugs and waste gas. Besides, getting the 750 to run AT ALL will be a huge win. Tuning it will be be bonus of this decade!

While I'm thinking about testing things (see "CDI" thread), what parts of the electrical system to I actually *need* to get the engine to run?

Will need a good fuse panel with main and ignition fuses intact. Start button, kill switch, starter relay, reg/rect, TCI, coils, plugs, alternator (need to check brushes), starter motor (need to inspect and lube), battery (of course)...

...that's it, right? I may have to hot-wire some things to bypass the missing computer, but that's about it, right? Also don't need various sensors (oil, neutral, clutch, side stand) I don't think, though I'll want to change the oil, put it in neutral, and listen for valves clacking (if the oil pressure doesn't rise)!

Just trying to think of how I can quickly get to just running an ignition test on the engine without spending all summer waiting on guages. If I can get to testing the engine, I can work the engine/carbs and electrical system (and brakes, and suspension) all in parallel. But if the engine is toast, there isn't much point in working on the rest.

Not much, but not nothing. Took the TCI from the 750 and put it on the 650. It did, indeed, run kinda rough, but it ran. Took the 650 for a little spin for maybe 30 minutes or so. Nearly got run over twice by idiots in cages.

You will need the Main and Ignition and that is it. You don't need lights or anything else. Just make sure the Ignition system (this includes the TCI and voltage regulator) gets the voltage it needs to keep alive and you should be just fine without anything else.

Pulled the coils, flasher relay, and cancelling unit from the 750 to test on the 650 tomorrow. About to go peruse the Haynes manual to familiarize myself with the other three relays (one is obviously the starter relay) so I know what they do and can test them on the 650 as well.

Hopefully some real progress on Saturday.

Tested the flasher relay and the self-cancelling unit. Also tested the starter cut-out relay. All good. Will test the coils tomorrow.

At least, I *think* I tested the starter cut-out relay. I have come to find out that none of the relays (other than the main starter relay) on the 650 are where they are supposed to be (see other thread), which is making things a little more complicated. I may need to re-run some relay tests.

But for now, it looks like most of the electrical system is a go. I need to remember to run continuity tests on all of the control switches on the clip-ons tomorrow.

Oh yeah. The side stand switch is toast, I think. I'll double-check tomorrow, but if I was testing the right leads, it read 20 Ohms in both positions. I could bypass it, but it should really be fixed at some point.

The Relay that controls the Safety Related is a "Special" Relay. It is, in fact, the Safety Relay and NOT configured like a generic power relay.

The Load and Trigger terminals are different from a Power Relay ... so, dont get confused.

Side by side they look like twins.
Power signal in and out ... totally different.

Generic Relay:

+__+
#__#

Safety Relay:

+__#
+__#

If you hook-up a generic Relay where a Safety Relay belongs ... the Safety Circuit becomes a nightmare.

The Bike will not start unless the Shifter is actually in Neutral.
Worse:
The Starter Button will engage the Starter Motor with the Bike IN Gear and the Clutch Lever >> Released!

This is an extremely hazardous condition.
The Bike will lurch forward as the Starter is engaged.

Look at a wiring diagram to see the difference.
This Post is so you know they are diffferent!

Sorry, my post wasn't very clear.

The relays are the correct relays and do what they're supposed to do. They're just in the wrong places. Someone has fiddled with the wiring.

For example, the relay mounted below the TCI is supposed to be the side stand relay, right? But if you start the bike and pull that relay, the headlight goes out. This makes sense only because the relay is marked blue. If you then go to where the headlight relay is supposed to be (by the self-cancelling unit), you find an all-black relay (the safety one). Sure enough, if you pull that relay, you have all kinds of problems starting the bike.

The right relays are attached to the right circuits... just mounted in all the wrong places. It's really strange.

I could verify it all completely, except the side stand switch has its leads cut, which makes it more difficult to test the side stand relay (and I have other things to work on yet).

Coil swapping today!