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

[tkent02]

Got the 650 cams in the old 550 engine, having a hell of a time measuring the cam timing. I think it's close, but I get different readings each time because the dial indicator tip won't stay where I need it to. Need to make yet another dial indicator tip, the one I made today isn't much better than the old ones. Think I need to make a curved one, to get around the cam lobe. Very annoying.

 

[tkent02]

OK, the cams in this beater 550 motor are at 107.5 and 110. Was shooting for 108/110 but that's close enough for a temporary beater motor. Time to torque the sprocket bolts, red locktite and... Holy cow the manual says 18 ft. lbs. Hmmm, 216 inch pounds. That seems like a lot for a 7mm bolt, can that be right?

I know Ray posted something about it a few weeks ago, but I can't find it anywhere.

 

[Buffalo Bill]

Steel in steel ok, not into aluminum.
Those are high carbon steel too.

 

[tkent02]

Yeah I guess that's right. Nothing broke anyway. It's all back together, going to try it out in the morning if it doesn't snow too much. Our 70 degree riding weather went back east someplace.

 

[tkent02]

Rode it a little, it pulls a bit harder the first couple thousand RPM... And that is all. The power comes on about like a Honda, no big rise in torque at 6,000 or so, no top end kick starting at 8,000 at all. What a dog. If this was what riding was always like I'd take up knitting.

Also it was really rich, especially at higher RPM, where it was slightly lean before. (tuned that way intentionally so it runs better up in the mountains where I mostly ride.) So rich it made as much power at half throttle as it does wide open. Blubberingly rich even. it almost seemed like riding a bike with sea level jetting here at 6,000'. I didn't think different cams would have much effect on jetting requirements. I guess I have a lot to learn.

Deciding whether to waste the time changing to smaller main jets to try it out some more or just put the 550 cams back in. Or just throw the 650 engine in with the 550 cams and let er rip.

 

[tkent02]

Interesting, dropped the main jets from 105 to 97.5, it's not perfect but close enough to see how it runs. Still on the rich side, can't believe how much difference the cam timing makes in the jetting.

Stronger down low than with the 550 cams, easier to get going from a stop. You can ride it around at 4,000 or so now instead of needing 6,000 to get out of it's own way. About like the old 650's power band only less powerful all around. The big top end kick starting at 8,000 on up as far as you care to take it is completely gone, might as well shift at the redline like a normal person. Boring.

I think I'm going to use the 550 cams in the 675, it's just more fun. Maybe tweak the timing for a little more midrange if I can do it without losing the top end blast.

 

[Nessism]

Can't wait for the ride report with the new engine. This thread almost makes me want to built one of those bikes myself.

 

[tkent02]

Just need to get a pipe figured out and put the carburetors together. Weather is too nice to take it apart again right now, been riding a lot.

But I'm getting ready to do it. Maybe tomorrow. or Friday....

 

[tkent02]

Heck with it, it's going in today.

 

[boontonmike]

Man, It's so nice to hear a comparison finally instead of just armchair engineering talk. I am confident in sticking with the 550 cams now. Thanks for the feedback.

Interesting, dropped the main jets from 105 to 97.5, it's not perfect but close enough to see how it runs. Still on the rich side, can't believe how much difference the cam timing makes in the jetting.

Stronger down low than with the 550 cams, easier to get going from a stop. You can ride it around at 4,000 or so now instead of needing 6,000 to get out of it's own way. About like the old 650's power band only less powerful all around. The big top end kick starting at 8,000 on up as far as you care to take it is completely gone, might as well shift at the redline like a normal person. Boring.

I think I'm going to use the 550 cams in the 675, it's just more fun. Maybe tweak the timing for a little more midrange if I can do it without losing the top end blast.

 

[boris.h]

also hoing to try the 550 cams first on mine, the "fun" is the first reason.

 

[tkent02]

 

[Chuck78]

I think I'm going to use the 550 cams in the 675, it's just more fun. Maybe tweak the timing for a little more midrange if I can do it without losing the top end blast.

that's pretty much exactly what I figured I would do as well. 550 cams have great top end, and the exhaust sound with a nice straight through aftermarket baffle is just pure bliss. Very authoritative snarly raspy tone.

looks like you swapped out the 550 engine for the 673! might as well, still winter, no sense in fooling around with the 550 engine, go for the gold.

 

[tkent02]

looks like you swapped out the 550 engine for the 673! might as well, still winter, no sense in fooling around with the 550 engine, go for the gold.

Still winter technically, but I've been riding every day, it's been in the 70s most afternoons. Even fairly warm up in the mountains, at least for a couple hours early afternoon.
I'm just sick of this thing not being finished.

 

[tkent02]

Just found a great thread about degreeing GS camshafts:

http://www.thegsresources.com/_foru...afts-Information-Required/page3&highlight=650

Excellent information from a lot of GSR guys, Suzuki-Don, Blowerbike, Tripivot, RapidRay, Chef, Nessism, Koolaid Kid, GregT and many others who posted one or two comments.
If I had found this a few weeks ago it would have been very helpful, would have saved me a lot of time and effort.

Alas, all I can do now is read about this stuff, I'm back at work and can't even look at the bike for a while. I'm also thinking I might use the 650 cams at least for a while.
The 550's huge top end kick is what is always making me wind it out to about 10,000RPM + and occasionally more, this engine with it's bigger heavier pistons might last a lot longer if I didn't do that everywhere I went.

 

[tkent02]

Okay, back at it. Looks like there's no way to fit the 650's front air box, the frame is just too tight. Plan B, K&N pods. I will also be using a Kerker 4-1 header, the one that was on it as a 550.

So for jetting, raise the needle a 1/2 clip position or maybe a little more, maybe up the main jet to a 125 for starters? Stock main is 110... Not real familiar with setting up CV carbs for a pipe and pods. A little research is in order.

Now for the pipe, it doesn't fit, the 650 head has a much wider hole for the pipe, although the actual port diameter is the same. Suzuki_Don had an elegant solution:

But I don't have a buddy with a lathe. So I improvise...

Cut some strips of aluminum just the right size... 1/16" x 3/4" by something like 5 inches, they seem to stretch when you do the next step...

Roll them up into a circle...

And tap them into place in the head.

This has the advantage of allowing me to use the 550 exhaust gaskets which I already bought, the strips hold them in line with the end of the pipe.

Tomorrow I'll throw some carburetors together.

 

[loud et]

I think rapid ray just posted a set of kn pods for 50$ if you need.

Edit.. it was chef......

 

[tkent02]

No, I bought some a while ago, thanks anyway.

 

[boris.h]

other solution, I found that a 600 gsxr would be.... so efficient and almost plug and play directly on the 650 head (do not fit inside 550 ports because they are smaller than the 650, you found it by yourself on the post above). If interested, I posted few pictures on my subject.

 

[tkent02]

The Kerker is on, seals pressed into the clutch cover, carbs are ready as soon as some jets get here, tighten up the motor mounts, put the sprocket back on the countershaft, add oil, connect a few wires, push the button..... I think that's it.