New to me 80 XS1100G

[TexinMaine]

So I was able to work out a barter deal on a 1980 standard. My 78 is a bit of a basket case and I knew it wouldn't be running this summer. So picked this up to curb that need to ride bug and take my time on the 78 and not rush because I am anxious to ride. Was being sold as a 1979 but when I saw the 85 mph speedo I was pretty sure it wasn't. The PO said that the right coil was bad because the 3 and 4 spark plugs had no spark, I got to looking around and found that they are both controlled by half of each coil. So I am assuming it is not the coil or has anyone heard of half of each coil failing? The spark plugs looked old and rusty so I am staring with them first. The battery is on the charger. so hoping to get to checking the new spark plugs tomorrow. I also noticed today that there might be an oil cooler attached to it. I didnt notice this when I bought it but as I was taking tank of and looking at the coils I thought hhmmm I don't think that is original. It has two hoses that turn to copper lines with some circular end that a bolt goes through. One attaches at the top of the cam cover and the other is lower where the engine and tranny meet. So does anyone have suggestions why 3 and 4 had no spark? Thanks!

Tex

[TexinMaine]

Locking cover was broke but luckily the broke off piece was still in the lock. So I turned the key and out it popped. Used JB Plastweld to repair.

Broken piece.



After repair.




And of course every job needs a supervisor.

[TexinMaine]

A few more pics from today.

Stripped down, luckily has some great tires, sidewalls and tread looks new, even still has the little nubbies.



Old spark plugs, left to right 1 through 4, will look up what the different coloration's mean.



Oil cooler??



Top hose attaches here.



And bottom here.

[3Phase]

Was being sold as a 1979 but when I saw the 85 mph speedo I was pretty sure it wasn't.

Hey, Tex! The TCI box is mounted on the front of the rear inner fender so it looks like you have an '80G. Nice bike!

The PO said that the right coil was bad because the 3 and 4 spark plugs had no spark, I got to looking around and found that they are both controlled by half of each coil. So I am assuming it is not the coil or has anyone heard of half of each coil failing? The spark plugs looked old and rusty so I am staring with them first.

You assume correctly because the ignition coils fire the spark plugs in pairs:
1&4 and 2&3 fire together in a 'wasted spark' setup.

Now, the fuel tank feeds fuel to the left and right side of the engine:
Cylinders 1&2 are fed from the left-hand tap; 3&4 from the right-hand tap.

The picture of the the spark plugs doesn't look too bad, #4 is firing, so check the right-hand fuel tap and make sure you're getting fuel to the #3 and #4 carburetors.

The battery is on the charger. so hoping to get to checking the new spark plugs tomorrow.

I also noticed today that there might be an oil cooler attached to it. I didnt notice this when I bought it but as I was taking tank of and looking at the coils I thought hhmmm I don't think that is original. It has two hoses that turn to copper lines with some circular end that a bolt goes through. One attaches at the top of the cam cover and the other is lower where the engine and tranny meet. So does anyone have suggestions why 3 and 4 had no spark? Thanks!

Tex

If the spark plugs really are not firing it'd be bad spark plugs or wires, not the rest of the ignition system. The spark plug boots are screwed into the ends of the spark plug wires and they can get corroded. They're just simple stainless steel core wires so unscrew the boots counter-clockwise from the wires; clean up the boots, trim off about 1/4 inch from the end of the wire and then put them back together.

The oil cooler is an aftermarket add-on. Be nice to it and make SURE the hoses and hose clamps are in good shape and correctly tightened -- not stripped -- or you'll be wearing hot engine oil on your walk home pushing a 900 lb bike with a seized engine.

.

[TexinMaine]

The oil cooler is an aftermarket add-on. Be nice to it and make SURE the hoses and hose clamps are in good shape and correctly tightened -- not stripped -- or you'll be wearing hot engine oil on your walk home pushing a 900 lb bike with a seized engine.

.

Yikes that sounds like it would really suck. Is there a benefit to having this?

[BA80]

If you do a lot of in city stop and go it does help quite a bit. I run one on my SG.

[DiverRay]

Yikes that sounds like it would really suck. Is there a benefit to having this?

NOT the way it's been plumbed!! The oil going to the head must FIRST go through the cooler. That is NOT a good thing. You can probably get a replacement oil line from ebay, or andreas here, cheap. I would then send TC a PM about his spin on adapter with oil cooler fittings, and purchase that. You can run without the cooler and have NO PROBLEMS with the bike. I just do NOT like the way the oil cooler is plumbed! I know there was a company that sold them back then, but I've always thought of it as redneck engineering, waiting to kill a good engine.

[BA80]

Ahhhhh.......I see what you're talking about Ray. I do have one of the SOFOCA adapters.

Yes, the redneck version you have is pretty iffy.

[3Phase]

Yikes that sounds like it would really suck. Is there a benefit to having this?

You don't need the oil cooler but they're nice to have. The idea behind the one on your '80G was to cool the oil going to the camshaft journals and remove some of the heat from the cylinder head as the oil drained back to the sump but it's not done correctly.

1) If you understand hydraulics: it's a giant accumulator stuck in the middle of a critical small-diameter oil feed pipe.

2) The rubber lines can swell up and balloon ever so slightly under pressure instead of delivering oil to the camshaft journals.

3) When everything gets nice and hot and oily, the hoses can slip off the hacked up oil pipe that used to feed oil directly to the camshaft journals.

4) There's no drain-back protection and the cooler is higher than the oil sump so the cooler and lines fill with air after the engine is shut off. The proportionally large oil cooler and its extra plumbing has to be refilled with oil by the small oil pipe every time the engine starts before it quits blowing bubbles through the oil pipe and makes enough pressure to feed the journals.


If you want to use an decent oil cooler, just find factory setup or, as Greg suggested, get the adapter from T.C.:-


T.C.'s Combo Spin-On Oil Filter Cooler Adapter=S.O.F.C.A.
Info and Installation Instructions
by T.C."TopCat" Gresham , posted 07-31-07


Just for grins (and because I couldn't find a factory rig), I put a B&M Supercooler on my '80G for riding out in the desert. It was a little bit of overkill but it worked really well:-


B&M Supercooler



.

[TexinMaine]

I got an e-mail from anderas(?) and he has an original line with banjo bolts he will sell me, I don't really do a lot of city driving and temps do not get that high up here in the great crappy north so I dont see a need for the cooler. So I was cleaning the carbs today and found a pinhole in one of my diaphragms. So was wondering if it is still ok to run this way ot if anyone knows a way to fix it. I have an extra set of carbs I got with my 78 but they are different from the ones on the 80, the needle is not as pointy and the brass piece has a smaller diameter, the spring is also smaller. Have an oil and air filter on order and should be here Friday. If anyone has any tips on the diaphragm I would appreciate them. Thanks.

Tex

Small pin hole over flash light



This makes the hole look larger than it really is.

[DiverRay]

You can clean the rubber well and smear a little RTV on the pin hole. The other option is use liquid tape.

[TexinMaine]

Thank you Ray, does it matter which side of the diaphragm?

[DiverRay]

Not really. I usually do BOTH sides with a hole like that. Smear it on thin on each side, so it meets in the middle of the hole. And, IF you can find the tube of Butyle Rubber (sp) it works even better. In black, if you can....

[TopCatGr58]

Hey Tex,

With regards to your ignition woes, don't even bother looking up the plug colors with THOSE PLUGS!!! They are from a poorly tuned and running engine...ignore them mostly for now! As stated, getting new plugs is a MUST, and then reconditioning the plug caps and wires connections, along with ALL of the other Harness electrical connections....grounds, etc....CLEAN!

Now one CAN get spark on only 1 of the 2 plugs of each coil but it's a rare condition. You're charging the battery...and a low battery/low voltage to the coils is how you can loose spark on 1 of the 2 plugs of a paired of plugs.

The coils are wasted spark, so they both fire at the same time....but they take a path from the coil...thru the wire, plug, and then ENGINE, then the other plug, and then back to the coil. The OEM coils are not that strong to begin with....15Kv usually. And with the 80...it's still using the ballast resistor which drops the running voltage to about 9 from 12. Now with poor connections from the battery, fuseblock, harness, TCI, coil primary wire connections, Ballast Resistor.....and you can have many sources for voltage loss. And THEN at IDLE, the ALT isn't charging very well....often barely at or below 12V, and so can also contribute to lack of voltage to the coils.

SO....with reduced voltage....the coils can not generate enough KV to allow the spark to be able to make the complete spark path, and so can fire just 1 of the 2 plugs on the coil pair! And then you add corrosion in the plug cap to wire connection....as well as corrosion inside the plug cap resistor....should be ~5kOhm, if much higher...can cause problems with spark jumping gap...will need to be replaced if you can't clean the resistor inside the cap.

Folks have already covered the oil cooler, and the carb diaphragm issue.

You didn't say how many miles were on the 80G? Also since the bike wasn't firing on all 4, it probably wasn't run much in the last few years. So...the next question is how do the compression numbers show? Also, have you checked the valve clearances?

Keep at it, you'll have it running in no time!!

T.C.

[TexinMaine]

So I hadn't really noticed the mileage when I bought it but it reads 62,392. I guess you can look at it one of two way, first it probably didn't sit around much with that many miles but also does that mean some stuff is about to wear out?

I checked the valve clearances today and only three where in the proper range. The rest where tighter. I hope I checked them right because wouldn't they become looser with use? Or is it possible they were recently adjusted? I couldn't find a metric feeler gauge so the measurements are in inches but they also had a mm measurement.

#1 ex .007" (.178mm) intake .003" (.076mm) I would almost call this one .0035" because the .004 was too snug and the .003 slightly loose

#2 ex .007" (.178mm) intake .006" (.152mm)

#3 ex .009" (.229mm) intake .006" (.152mm)

#4 ex .007" (.178mm) intake .004" (.102mm) again I would call this .0045 as the .005 was a bit too snug and the .004 a bit too loose.


So are these ok because they are not too loose or do I need to put thinner shims in? Why would they be tighter, are the valves worn and need replacement? Thanks!

Tex