Finally getting around to the 550/699 project....

[tkent02]

Also found out today someone a long time ago in a galaxy far far away upgraded to an 18 pole rotor and stator. Woohoo.

Going to powdercoat the case covers Satin Black, cylinders and head too if I can figure out how to get them clean enough.

The Matte Black just wasn't cutting it.

 

[loud et]

I really like that graphite color you used on those other parts....
What did you use those on?

 

[tkent02]

Did nothing with them, they are just sitting on the oven like some kind of lost garage art. The ignition cover is cracked, the clutch adjustment cover looks bad up close because some of the clear was still there, the others are fine. It was just a test, my first powdercoat victims if I remember correctly. Just grabbed a few parts off the shelf and did it up.

 

[loud et]

Rodger that.

 

[tkent02]

A year and a half later...

Got the cylinder and head powder coated, the cylinder and the head look great. It was actually fairly easy to get the cooling fins done. If you look closely there is a little less "color" way back in between the fins, but you have to know where to look to see it. I think there's probably a trick to doing cooling fins, but I haven't found it.

Got the top end back together, not quite done yet, but I'll finish it up in December. Just too many projects and too little time.

 

[Buffalo Bill]

How come so long, did you become bored with the idea?
Life's too short to resurrect the 1970s.

 

[tkent02]

How come so long, did you become bored with the idea?
Life's too short to resurrect the 1970s.

No, not bored but my interest comes and goes. I have a job, when I'm working I'm gone for weeks or maybe a month at a time. When I get home other things need attention, several bikes need to be ridden, cars need fixed, all the usual excuses. In the summer I go out on the dirt bikes at every opportunity, it kind of kicks my ass so nothing gets done for a few days. This past month Christmas got in the way.

Tonight, powder coating the valve cover and a few smaller pieces. I'm fired up to finish the head tomorrow. The head is just sitting on there in that last picture, no valves in it, that's an old 750 valve cover sitting on there to keep dust out, in a few days it will look better.

 

[tkent02]

OK, it's all done. Just the clutch cover to go, because I broke the glass in the oil window taking it out to powdercoat it. Everything else is finished. Valves adjusted, screws and bolts all torqued, cam chain tensioner rebuilt, all of the little things are ready to go, except carburetors. I'll just throw together a set of BS32s and see how it runs....

 

[Buffalo Bill]

What are you doing for the rest of the bike?

 

[UncleMike]

Man, I can't wait to see this finished!

 

[tkent02]

It's ready to go, mostly stock '78 GS 550 with a big front brake, spoked wheels from an early GS1000, Hagon shocks for now, emulators in the forks. Been riding it a while with a spare 550 engine in it. Nice bike but up at this elevation you really have to wind it out to get anywhere. They are a lot better at sea level. That and being a '78 it has VM carburetors which really suck if you ride where there are huge elevation changes every day.

Was planning on turning a second 550 into a single seat cafe racer type thing with a kickass 700cc engine but seriously I don't know if I'll ever get around to it. Maybe one day.

 

[Buffalo Bill]

At high elevations, maybe take a step more advanced and try a fuel injection mod?
I was gonna suggest turbo, then remembered that includes FI.
PS: Was over at a client's house today…Lo and behold…he had a museum quality 84 Kawi 750 turbo!

 

[tkent02]

At high elevations, maybe take a step more advanced and try a fuel injection mod?
I was gonna suggest turbo, then remembered that includes FI.
PS: Was over at a client's house today…Lo and behold…he had a museum quality 84 Kawi 750 turbo!

Actually the CV carbs run beautifully up to 14,100' (highest road around here ) down to sea level, and anywhere in between.

Fuel injection, maybe one day but it's not high on my list. The CVs just run too well.

 

[Guest]

About dang time Tkent! Lets see the pics.

 

[tkent02]

Pics, patience glasshopper. Awaiting parts, and I'm not putting the engine in the bike until I have everything ready to make it run. Still riding it as a 550.

First comes cam timing. Got set up with a piston stop, a steel platform to mount the dial indicator on the head, a long ass wrench to turn the crank, and an 11 7/8" degree wheel.

Now where do I want to set these cams? Stock 650 cams, slotted 550 sprockets, a stock 650 head and pistons, no porting or anything. Will be running BS32s from a GS 650, due to the elevation changes around here. What I want is strong mid to upper RPM, don't care about off idle grunt or the strong top end kick that the 550 gets at 9,000 or so. Like a strong pull from 5,000 - 8,000 ish? You know, normal riding RPM. Now mind you if it does in fact end up with a strong kick at 9,000 or so I wouldn't mind, but that's not my first concern.

Is there a good place to start? Is a number that works on an 1100 going to work the same on a 550/675? The racer dudes seem to like 106 - 108, but those are different engines. Trial and error and lots of test riding?

If I did it right the centers are 106 and 118 now, with the stock positioning of the sprocket, which seems odd to me. Isn't that 118 way too far out there? Is that maybe something they would do for some emissions reasons or something? Did they just screw it up by that much? Or is that something that works on a 550 sized engine? I checked that the 1, 2, and 3 arrows on the sprockets are in the same place in relation to the bolt holes on the 550 and 650 cams/sprockets, they are.

Planning on hooking this stuff up to a standard 550 engine tomorrow to see what that one is set at.

Where would you guys set them to tart?

 

[tkent02]

RapidRay suggests 108 / 110, I'll start there.

 

[Chuck78]

Holy smokes, 106/118 is much further out than I could imagine..I had read on here that there was a broad desparity of cam timings on our engines, hence you might find 2 identical models with completely different engine power carachteristics.

Generally people well versed in cam timing say to put the GS at 104/106 for a huge boost in mid range street torque (I'm envisioning 4000-7000rpm), and to set them both at 110 for top end horsepower. Your Ray recommendation falls right in line with that. Ray is an awesome wealth of engine knowledge.

Web actually have a massive writeup on cam timing, and changing lobe seperation angles.
Have you seen this?
http://www.webcamshafts.com/mobile/degreeing.html

 

[tkent02]

I have seen it, thanks. I think my problem is in the dial indicator mounting. Don't have a long enough extension on the tip, it's hard to get it in line with the valve without hitting the cam lobe as it comes around. Had it at a bit of an angle at first, got funny readings. It reads differently on the way back up than it did on the way down, which skewed everything. After redoing all of the measurements a couple times it's much closer to 106 / 108, but I'll recheck it when I get the extension thing figured out. Also Chef is sending me some carburetor parts I need to put a set together, that's the last big thing I need to finish this up.

 

[tkent02]

Man this is going slowly. The engine is done, cams are timed as closely as I can, but it's still hard to get a good reading on the dial indicator. Bought a set of dial indicator tips, but none are long enough and skinny enough to get to the shim bucket without rubbing on the cam lobe when it comes around which knocks the tip around. It's difficult to get within three degrees consistently.

I wanted to know how much of the difference in power and torque were due to the increased displacement and the shape of the head and pistons, and how much was due to the 650 cam, so I put another set of 650 cams into the 550 engine. The 550 cams have lobes that are much wider visibly than the 650 cam lobes. Finding out a few things about the cam sprockets too. The 550 sprockets need to be drilled to 7mm, and the timing is different than the 650 sprockets. The numbers and arrows for setting them in the head are indexed differently in relation to the bolt holes. Looked at a bunch of 750, 850, and 1000 cams I have here, there are several different choices in how their sprockets are indexed. Anywhere from 3 1/2 to five teeth between the bot hole and the arrow and number. Some have 6mm holes, some have 7mm. Also found one aftermarket 750 exhaust cam that fell down behind the wall with a slotted sprocket. They are all the same 30 tooth sprocket that the 550 uses so good to go. Trying different combinations of sprockets to get close to the timing of the 550/675 engine. Think I'll end up using the slotted sprocket, but...

Being hampered by the dial indicator tips. Seems worse on the is 550 head than on the 650 head for some reason. I think I need to make one about three inches long to get in there...
And no one in town sells 4-48 taps to make such a tip. Looks like another time suck coming.

 

[tkent02]

Speaking of time suck, I just picked up a 1982 R80ST. I'll try not to start on it until this 675 project is done.