1980 GS1100E - completing the build

[astroboiler]

I bought a 1980 1100E for next to nothing back in December. Among other things, it was missing the carbs, airbox, and the title. The fella that I bought if from hadn't done any work on it, and he didn't have the title. So using the resources and suggestions on this site, along with the factory service manual, I got her running by March and was riding around by May.

Around the time that I first fired her up, I was able to track down the title holder and got the title so the bike could be registered in my name. This previous owner told me that the bike was his "go-fast, hot-rod" and it was built with a bunch of performance parts. He also told me the reason that the carbs were missing when I bought it was because he had some smoothbores for it that he had pulled just before he got rid of the bike, and he offered to sell those to me on the spot. I declined the offer for the carbs, got the title, and left.

I've ridden this bike around for probably 500 miles on a set of stock BS34SS carbs that I bought and refurbished from a member on this site. I am also running a stock airbox, which I bought from another member. The exhaust is a badass 4-1 with a Kerker K2 muffler. This exhaust came with the bike when I bought it. I get a mist of oil from the valve cover gasket when I am going much faster than highway speed. Also, the shift return spring needs some attention because I have to slip my toe under the shifter just before downshifting. So I decided to pull the engine and address these issues while also checking out the internals of the engine.

The obvious go-fast parts, external to the engine, are:
the 4-1 header and Kerker K2 muffler
3 ohm green Dyna coils
Lockhart oil cooler

Now onto the engine. I need some help identifying some of these parts, so I took lots of pictures. The cams appear to be Megacycle drag race profile cams. 6 dot 3 and 8520 are stamped right up next to the sprocket on both exhaust and intake cams. This matches up with the 385-20 part number, which is a hardfaced cam with .390 lift and 252 degress of duration.

The sprockets are the stock ones but the intake sprocket kinda looks like it has been slightly slotted.

Here is the intake cam:

And here is the exhaust cam:

With a rocker ratio of 1.52, the intake lift is (1.380-1.124)*1.52=0.389 inches, right? And so then exhaust lift is (1.372-1.116)*1.52=0.389 inches.

Here's a pic of the cam chain. DID 219 FTS endless chain. Is this stock or HD?

Valves are stock diameter - 23 mm exhaust and 27 mm intake. I pulled two intake valves and the heads are worn. I unfortunately did not snap any pictures.

 

[astroboiler]

1980 GS1100E - completing the build

I am pretty sure I have HD valve springs and definitely have hardwelded rockers. I snapped some pictures of springs and rockers

Here are pictures of an intake port. There has been some port matching to the intake boots, and some mild porting and smoothing in the bowl area.

Now onto the bore. Appears to be bored over to 75 mm, which I understand gives a displacement of 1166 cc's. Here is a picture of a piston. Can anyone identify these? They are marked with ?C? on top and ?4084? underneath. I would guess a C.R. of 10.5 or 10.25:1 since that seems pretty common. I think Wiseco made one and MTC made the other.

In the bottom end, I understand from reading on this forum that I am looking for a HD backing plate for the clutch hub, 750 oil pump gears, undercut (and possibly overcut) transmission gears, and a welded and balanced (essentially "race-prepped") crankshaft.

Here is the clutch hub. The backing plate is missing, and the helical gear is uber welded to the basket. And no springs either. What's going on here?

I appear to be missing the piano wire clip, but I have one more fiber plate, so perhaps it is the Ape "Extra Plate" clutch kit.

 

[astroboiler]

1980 GS1100E - completing the build

Here are the oil pump gears, and they are high volume 750 gears. 38T drive, 29T driven.

Here are some pictures of the transmission. Up and down cuts.

And here are pictures of the crank. I see welds and some balancing. And no cracks in the case webbing behind cylinders 3 and 4.

After finding all of this, I called up the PO and bought those carbs he was offering back in March. These Keihin CR Special 35?s are mine now.

 

[TxGSrider]

It looks like you've got a good solid foundation for a strong bike. Since you're replacing the intake valves anyhow, you might consider going +1mm.

 

[astroboiler]

It looks like you've got a good solid foundation for a strong bike. Since you're replacing the intake valves anyhow, you might consider going +1mm.

Yessir that's the plan. I understand 28.5 intake and 24 exhaust can fit on the stock seats.

Anybody seen a clutch hub like this before? Is it a hackjob or is there a method to the madness? And is this the stock cam chain?

 

[TxGSrider]

That's a pretty common upgrade to the clutch basket as they are known to be one of the 1st things to come apart in these motors. You're ahead of the game.

EDIT: After looking at that clutch again, I'd say maybe you should replace it. I don't know how I missed the springs being removed and welded solid there.

 

[Guest]

The Clutch basket is not an 1100 of any type....looks like a gs750/850 type. needs junking, especially after being butchered like it has been! camchain is a stock type replacement. nick

 

[rapidray]

That clutch hub IS a hack job!!! I build hubs if you need one. Also, those cams are HUGE for a street motor and your rocker arms do NOT look like welded rockers to me, need better pics to be sure. Let me know if I can help.
Ray.

 

[astroboiler]

Yep this clutch basket is gonna have to go away. BikeBandit says that the 1980 GS1100E primary gear should have 87 teeth, and so does mine. I count 49 teeth on my crank gear. Is this the stock gear?

 

[astroboiler]

Here's a pic from a different angle of one of the rocker arms.

Yeah I am pretty stoked about the cams. This will be a race-only bike. I have your number Ray so I'll give you a shout about a hub.

Is this cam chain acceptable on a high performance motor, or should I be using an APE or Tsubaki HD chain?

That clutch hub IS a hack job!!! I build hubs if you need one. Also, those cams are HUGE for a street motor and your rocker arms do NOT look like welded rockers to me, need better pics to be sure. Let me know if I can help.
Ray.

 

[astroboiler]

Damn it. $80 later and I have the exact same cam chain that I already had.

APE's heavy duty cam chain for the GS1100E is a DID 219 FTS endless chain. Can't really be mad at APE, it is not like they said they manufactured it or anything. But it would be nice if they gave a little more info so I could cross reference. I would have spent those same dollars at their store, but instead on cam sprockets or a push/pull throttle or something that I actually needed.

Hopefully the next guy reads this thread and saves himself the headache, since asking a question twice in the same thread apparently gets the wrong answer.

 

[TxGSrider]

Damn it. $80 later and I have the exact same cam chain that I already had.

APE's heavy duty cam chain for the GS1100E is a DID 219 FTS endless chain. Can't really be mad at APE, it is not like they said they manufactured it or anything. But it would be nice if they gave a little more info so I could cross reference. I would have spent those same dollars at their store, but instead on cam sprockets or a push/pull throttle or something that I actually needed.

Hopefully the next guy reads this thread and saves himself the headache, since asking a question twice in the same thread apparently gets the wrong answer.

Actually you already made me feel better about using the DID chain I bought for mine... so you did help someone (kinda). lol

 

[astroboiler]

With the cases split and the crank and transmission gears removed, I was able to wash the upper and lower cases real well in a mineral spirit parts washer. I checked the 20 pin length of the APE chain that I had in there, and it was like 5.9 inches, whereas the spec for replacement is about 6.2". I bought a little tube of Permatex Ultra gray and started rebuilding. Nothing real interesting here - just reassembling according to the factory service manual, but I figured I'd share anyway.

Here is the crank in the upper case.

And now the gears are in.

I put a bead of Permatex Ultra gray on the mating surfaces (after giving them a once over with a brass brush and wiping with rubbing alcohol) and reunited the cases.

I started to torque the first 12 lower crankcase screws down, and I guess I didn't feel my torque wrench click on one of the long 8mm's, because I snapped it. I was fortunately able to extract it without much issue.

I needed a handful of other things anyway (lock washers, piano wire clip, OEM gaskets, etc.) so the crankcase screw went in that order and I should have it all early next week. This weekend I am headed up to see Dan Marrs at MARRS Performance Motorcycles. Very cool dude if any of you know him.

 

[astroboiler]

I received the assorted nuts and bolts and gaskets from Partzilla and got back to work. I torqued the crankcase bolts, cleaned the sump screen, put the oil pan on with a new gasket, tightened the new crankcase securing nut, and got the engine upright.

I put the bearing retainer and oil gallery plate screws in with loctite and put all the clutch stuff back in according to the factory service manual. I opted to include the piano wire clip though I have heard, "nobody uses those", but that is my 0.02.

To tighten the clutch sleeve hub nut, I found that the "AC Clutch Holding Tool" which can be rented from AutoZone will do the trick in place of Suzuki's clutch sleeve hub holder. It worked great and I was able to give the clutch nut its 50.5 lb.ft of torque.

Here is another pic of the AutoZone tool. I think the rental deposit was $28.

I am in the process of machining a connecting rod stopper so that I can tighten the clutch spring bolts. I have an extra fiber clutch plate, so that somewhere in the stack I will have two fiber plates against each other. Is this correct? Where should it be (top, bottom, middle)?

 

[dorkburger]

I pretty certain that fiber plates should never touch one another.

 

[astroboiler]

I pretty certain that fiber plates should never touch one another.

Yep, looks like I was short one steel plate. Thanks for your reply.

I ordered a genuine Suzuki steel clutch plate and that came in last weekend. I soaked the fiber plates in the oil that I drained from this bike when I took it apart in the fall (I knew I was hanging onto it for some reason) and put the fibers and plates in the basket.

Also per the FSM I coated with Permatex ultra gray the normal faces where the cases meet in the clutch, rotor, and ignition areas. I started torquing down the clutch spring bolts, and snapped one of them off.

Fortunately I was able to extract this one with needle nose pliers. I wonder if 37 years of tension from the spring caused fatigue? I wouldn't think 8.5 ft.lbs of torque would be the culprit.

The threads were still in good shape, so I got a replacement 6mmx30mm screw and torqued all 6 incrementally to 104 in.lbs.

I picked up a Dyna-S ignition module last week too. I have the green 3.0 ohm Dyna coils already on the bike and they work great. My plan is to get the bike running again with the new Keihin CR Specials and the stock ignition plate (minimize the variables ya know?) before installing the Dyna-S. Next will be getting the pistons back on the rods and installing the block.

 

[astroboiler]

I got the piston rings in their correct positions, oiled the big and small ends of the rods, lightly oiled the pistons and put them back on the rods. Special care was taken to not drop the piston circlips down into the crank case.

When I bought all the nuts and bolts and gaskets from partzilla, I didn't think about replacing the base gasket or the cylinder sleeve o-rings. But I have placed an order for these and should have them soon. I had the motor disassembled this far last year right when I bought the bike, so from this point forward I feel confident. Degreeing the cams in my new slotted sprockets will be new for me and I have never played around with Keihin CR Specials either, so I'm looking forward to this.

 

[cbxchris]

Boy, does that bring back memories. Great engines. When I was looking at your cases I sat and thought of all the work a good set of drag racing cases had in them set up for a 3 speed. Sadly, I must say the Z-1 was better but not performance wise until the billet heads.