Adjusting cam timing on GS550E

[Nessism]

Hate to say this but your exhaust cam may still be off a tooth. Looks like the 1- mark raised up when you installed the tensioner. How about another photo focusing on just that exhaust cam sprocket?

Sometimes it's hard to judge perfect alignment, and you have to check a couple of positions and then just pick the one that looks best because neither is perfect.

[scott]

Fantastic! I bet you even used a torque wrench on those cam cap bolts. Personally, I like a little extra valve clearance, but at 8k, this motor hasn't done much and , you'll be doing it again soon to satisfy your curiosity.Play with that tensioner, till you grasp how it works inside the motor when unlocked.

Actually, I did use a torque wrench. I finally broke down picked one up a few days ago (hard to find one locally that goes below 10 ft-lbs).

[scott]

Scott do I understand correctly that you are placing two feeler gauges, a .08 & .06mm together and sliding them between the lobe base circle and the shim to do your measurements?

The valve clearance for your motor should be .03 to .08, if you are inserting both feeler blades under the cam then that totals .14mm which is way too wide for valve clearance.

I repeat the clearance is .03 to .08mm or .001" to .003".

Yes - on the valve adjustment I did about a month ago, I could have sworn that IN2 valve had .10 mm clearance. Now, I can fit a .08 & .06 mm together (.14mm) and get it in there. It takes some effort / there's quite a bit of drag but it isn't until I do a .08 & .07mm together (.15mm) that I really can't fit it in. Oddly, there's drag on IN2 even at smaller sizes. I may need to get new feeler gauges (even though these are pretty much new). On a different valve, I had a .08mm go through smooth but the .07mm had drag. I did another check and this is what I have (Spot | Clearance Guess | Notes):

• EX1 | .09 | .08 is smooth, .09 has some slight drag, .10 does not fit
• EX2 | .08 | .07 has some drag, .08 has slight drag, .09 does not fit
• EX3 | .06 | .07 and .08 can be forced in but seems like too much effort
• EX4 | .08 | .08 fits smooth, .09 does not fit
• IN1 | .11 | .10 had some drag, .05+.06 was very smooth, .05+.07 did not fit
• IN2 | .13 | .08+.07 does not fit, .08+.06 some drag, .07+.06 some drag
• IN3 | .08 | .09 does not fit, .06 fits with ease, .08 has slight drag
• IN4 | .08 | .09 does not fit, .06 fits with ease, .08 has some drag, .07 has more drag

I guess it's safest to go to the feeler gauge that doesn't fit and assume it's 1 or 2 sizes below that.

IN2 definitely seems suspect so I'll look into increasing the shim size on that one.

[scott]

Hate to say this but your exhaust cam may still be off a tooth. Looks like the 1- mark raised up when you installed the tensioner. How about another photo focusing on just that exhaust cam sprocket?

Sometimes it's hard to judge perfect alignment, and you have to check a couple of positions and then just pick the one that looks best because neither is perfect.

It definitely raised up some with the tensioner. It's hard to say whether moving it would put the 1-mark below the surface or not. Here's another pic:


I assume it would move the distance between 2 pins. That SEEMS pretty low.

[Nessism]

Guess that's as good as it's going to get. Moving it down would put it way down. As the chain wears the mark moves up so maybe that's why the mark seems to be high.

[hampshirehog]

It's a job to tell from a photo but I would be wary of that being a tooth out. You have to get your eye bang on level with the top of the cylinder head and look along the gasket - the arrow should point at the gasket.

[tom203]

Actually, I did use a torque wrench. I finally broke down picked one up a few days ago (hard to find one locally that goes below 10 ft-lbs).

I misplaced my simple torque wrench for this stuff- My deluxe one doesn't go below 10 ft-lbs. Don't go crazy on valve clearances-err on loose side; I bet with some running, this motor will push the valves into their seats fairly quick as it's probably sat for a long while waiting for you.

[Suzuki_Don]

It's a job to tell from a photo but I would be wary of that being a tooth out. You have to get your eye bang on level with the top of the cylinder head and look along the gasket - the arrow should point at the gasket.

Scott, rotate the motor a couple of times by the end crank nut/hex and stop with the 1-4T lined up perfectly with the index mark then get a photo for us with the camera lined up exactly horizontal with the top face of the cylinder head where the valve cover sits so we can see exactly where the 1 arrow is pointing without any reflex error. If you know what I mean. Your photos are taken looking down slightly onto the motor and it's hard to see the exact position. We need to be able to se it square on.

Keep at it - not far away now.

[scott]

I did another check and this is what I have (Spot | Clearance Guess | Notes):

• EX1 | .09 | .08 is smooth, .09 has some slight drag, .10 does not fit
• EX2 | .08 | .07 has some drag, .08 has slight drag, .09 does not fit
• EX3 | .06 | .07 and .08 can be forced in but seems like too much effort
• EX4 | .08 | .08 fits smooth, .09 does not fit
• IN1 | .11 | .10 had some drag, .05+.06 was very smooth, .05+.07 did not fit
• IN2 | .13 | .08+.07 does not fit, .08+.06 some drag, .07+.06 some drag
• IN3 | .08 | .09 does not fit, .06 fits with ease, .08 has slight drag
• IN4 | .08 | .09 does not fit, .06 fits with ease, .08 has some drag, .07 has more drag

I guess it's safest to go to the feeler gauge that doesn't fit and assume it's 1 or 2 sizes below that.

IN2 definitely seems suspect so I'll look into increasing the shim size on that one.

I did adjust the IN1 and IN2 shims yesterday so my current clearances are roughly (Spot | Clearance | Shim)

• EX1 | .09 | 2.58
• EX2 | .08 | 2.63
• EX3 | .06 | 2.67
• EX4 | .08 | 2.62
• IN1 | .09 | 2.61
• IN2 | .08 | 2.67
• IN3 | .08 | 2.67
• IN4 | .08 | 2.56

Good enough.

Scott, rotate the motor a couple of times by the end crank nut/hex and stop with the 1-4T lined up perfectly with the index mark then get a photo for us with the camera lined up exactly horizontal with the top face of the cylinder head where the valve cover sits so we can see exactly where the 1 arrow is pointing without any reflex error. If you know what I mean. Your photos are taken looking down slightly onto the motor and it's hard to see the exact position. We need to be able to se it square on.

Ack! I already have the cam cover reassembled. I think at this point I'm just going to see if/how it runs.

Will my mixture screws be affected by the cam timing adjustment? This is what my plugs looked like when I removed them to do the cam adjustments. The plugs are only a month or two old so I assume Plug #4 is still usable.


I sprayed plug #4 with some De-Oxit so it looks a little better (different lighting but..):


I was planning to back out screw 1 a tad and turn in screw 4 a bit.

[tom203]

I did adjust the IN1 and IN2 shims yesterday so my current clearances are roughly (Spot | Clearance | Shim)

• EX1 | .09 | 2.58
• EX2 | .08 | 2.63
• EX3 | .06 | 2.67
• EX4 | .08 | 2.62
• IN1 | .09 | 2.61
• IN2 | .08 | 2.67
• IN3 | .08 | 2.67
• IN4 | .08 | 2.56

Good enough.


Ack! I already have the cam cover reassembled. I think at this point I'm just going to see if/how it runs.

Will my mixture screws be affected by the cam timing adjustment? This is what my plugs looked like when I removed them to do the cam adjustments. The plugs are only a month or two old so I assume Plug #4 is still usable.


I sprayed plug #4 with some De-Oxit so it looks a little better (different lighting but..):


I was planning to back out screw 1 a tad and turn in screw 4 a bit.

Well, you were doing lots of messing with those mixture screws, so I'd check them- 2 to 3 turns out is a start. Those plugs should clean out with some running. I think your cam timing is fine- the pics can be deceiving- and I think you grasped what was needed. Get this thing burning fuel!

[scott]

Okay - got the bike reassembled and put on a remote fuel tank. I started it up and brown "water" started dumping out of the airbox drain. It was a lot more than a drip and previously it took a little while before there would be slow dripping! The liquid didn't smell like gas though. I was thinking I really messed things up but the dripping actually seemed to stop after idling for a while.

Get this thing burning fuel!

Yeah - I was hoping that would be the case.

I put the actual fuel tank on and took it out. Woah - it actually scared me at how much the bike pulled (remember I'm a very new rider). At least compared to how it was before, it really felt the bike was flying. The front wheel didn't come off the ground but it felt like I could have. Best of all, when I parked the bike, NO DRIPPING! I'll have to take it out again to make sure but I can't believe it. I think my dripping airbox issue may actually be fixed!

A couple of side questions.

1. What RPMs do you want the bike to be at when warming it up on choke? I actually think the choke is working as intended for the first time. I used to have to give it a lot of choke to get the RPMs to around 1700 when the bike was cold. This time the RPMs shot up to 3K RPM which seems pretty high (in the garage at least). I had to put the choke just barely on - I guess that's a good thing.
   
2. It may be that I just need to get used to it but is there a way to adjust the throttle to be less ... touchy. Every bump in the road was enough to nudge my wrist and made the ride a little jerky. Maybe I'm just not used to my new-found torque.
   
3. I noticed something odd when I was putting the fuel tank on - it doesn't sit even. It's tilted to the right side (AWAY from the petcock side). Can't be normal right? I never took notice before but the 2 tank cushions that it slides into seem to be different sizes. Are they supposed to be different sizes but just on opposite sides (so the tank tilts towards the petcock side)? Or are they supposed to be the same size? As it currently is, I can't be working with my full tank capacity.

Thanks so much for all the help!

[Suzuki_Don]

Scott the two tank cushions should be the same size. Order a couple of new ones from Suzuki then you will know you have the correct size ones fitted.

[tom203]

1. What RPMs do you want the bike to be at when warming it up on choke? I actually think the choke is working as intended for the first time. I used to have to give it a lot of choke to get the RPMs to around 1700 when the bike was cold. This time the RPMs shot up to 3K RPM which seems pretty high (in the garage at least). I had to put the choke just barely on - I guess that's a good thing.
   
2. It may be that I just need to get used to it but is there a way to adjust the throttle to be less ... touchy. Every bump in the road was enough to nudge my wrist and made the ride a little jerky. Maybe I'm just not used to my new-found torque.

"Choke" operation sounds normal- yeah, you just turn the "choke" (actually fuel enrichment ) down so revs don't scare you. I wait maybe 30 seconds (from cold start) and go- as it warms up, lose the choke and should have stable idle. Adjust idle stop screw to about 1100 rpm. You might want to rotate throttle grip assembly so it suits you. You don't need a death grip on the throttle. It takes time to relax a bit; avoid traffic as best you can, stay vigilant as car drivers have way too many distractions these days.

[scott]

Scott the two tank cushions should be the same size. Order a couple of new ones from Suzuki then you will know you have the correct size ones fitted.

Looks like they're cheap so I might as well.

"Choke" operation sounds normal- yeah, you just turn the "choke" (actually fuel enrichment ) down so revs don't scare you. I wait maybe 30 seconds (from cold start) and go- as it warms up, lose the choke and should have stable idle. Adjust idle stop screw to about 1100 rpm.

Makes sense - it's just so different from how it behaved before. So far I haven't even needed to let the bike warm up before the shifting is smooth. I can't imagine that has anything to do with the cam timing but maybe the bike is just warming up quicker now.

You might want to rotate throttle grip assembly so it suits you. You don't need a death grip on the throttle. It takes time to relax a bit; avoid traffic as best you can, stay vigilant as car drivers have way too many distractions these days.

I actually think some of my jerky-ness is coming from a bogging / hesitation around 3500 - 4200 RPMs. From what I've been reading this is a lean condition? Nessism's new carb guide says reducing the needle spacer is a solution for addressing lean midrange.

Is this my next step? Or am I at the point where I should consider getting a carbtune for a vacuum synch (instead of my homemade manometer) to possibly address this? Am I correct that the mixtures screw are not related since that only affects idle mixture?

[tom203]

Scott said....."I actually think some of my jerky-ness is coming from a bogging / hesitation around 3500 - 4200 RPMs. From what I've been reading this is a lean condition? Nessism's new carb guide says reducing the needle spacer is a solution for addressing lean midrange.

Is this my next step? Or am I at the point where I should consider getting a carbtune for a vacuum synch (instead of my homemade manometer) to possibly address this? Am I correct that the mixtures screw are not related since that only affects idle mixture? "
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That brown stuff that used to spray out carbs, might be now causing one or more of the vacuum slides to stick. It doesn't take much to interfere with their desired operation. I spray mine with silicone, hoping that any crap will fall away. Yours might improve with more running- lots of stuff does! Indulge yourself and get a carbtune or equivalent- I'll bet you will put it to good use. Me, I'd put at least 1k on this engine before contemplating fine tuning.