SRIS question

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Coyote
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SRIS question

Post by Coyote »

I have (like many others have ) eliminated the recycle system from my 550.
My question is what happens to the injection oil that eventually builds up from the crank bearings oil supply?
I was born with nothing and still have most of it left.

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Suzsmokeyallan
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Post by Suzsmokeyallan »

The only way you should have a severe build up of CCI oil in the lower c/case is if the oil line check valves are leaking.
Under normal use, a bike that has been sitting for a while will have a SLIGHT excess of smoke on start up. You would normally see this being burnt off as the small smoke cloud once youre warming the bike up.
If its a real wild fire of smoke that engulfs you and all surrounding persons standing nearby, then chances are you'll need to inspect the check valves and oil pump setting.

From what ive seen with Suzuki over the last 30 plus years of dealing with their two strokes is that they were a bit generous with the supply of oil in the CCI system.
Now that all the modern 2 stroke oils are much better at doing their job, its a double dose of excess for the old CCI system.
Having oil pumps that tended to discharge more oil as they wore in, or out in this case, only compounded the problem.
ANYWAY,,,,, as long as the mixture of oil to fuel ratio by the pump lever setting is giving you a correct looking light tan plug reading, and your check valves are working, all will be fine.
Two strokes, its just that simple.

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Post by Coyote »

Bike doesn't smoke at all. And yes the oil pump is set up correctly. If anything - slightly heavy.
But I'm still confused. I mean the whole time the engine is running, oil is being fed to the crank. Logic tells me it has to be emmited or consumed somehow. Hence the SRIS. Without it, what happens to that oil?
I was born with nothing and still have most of it left.

.
1978 GS1000C
1976 GT550 ongoing money pit.
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Post by Suzsmokeyallan »

Ok heres how it basically works, the CCI oil from the lines goes to the main bearings where it then spins around and is flung to the edge of the bearing. They have a lip built onto the side of the main bearing facing the crankpin, (the other side has the seal), and an oil slinger on that side of the crank half that the lip on the bearing fits inside of.
So the oil leaves the main bearing and is captured by the slinger due to centrifigal force acting on it.
From here it goes to a hole in the slinger thats aligned with the partially hollow crank pin. It enters the crank pin and then flows out cross drilled holes at the lower con rod bearing section.
From here it then gets mixed with fuel and oil in the lower crankcase and finds its way up to the top end piston pin, along with other oil and fuel coming from the intake oil fitting thats also delivering oil.
So youve got two intake sources of oil in each cylinder, one delivering pure oil to the main bearings first and the con rod and piston pin next, while the secondary one is delivering oil with the intake fuel charge.
So the oil you speak of is being used, its just that it gets diluted and used with the intake charge after its done most of its primary work to lube the main and lower rod bearings.
Two strokes, its just that simple.

69 Suz U70
69 Suz T500
72 Suz GT750 cafe
74 Suz TS250
74 Suz GTXVR project
75 Suz RE5
75 Suz GT750
76 Suz TS400
76 Suz GT750
81 Suz GSX1100
86 Suz RG500x2
88 Hon CR500
93 Hon CBR900RR
98 Suz GSF1200x3
15 Kaw Ninja H2
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Post by H2RICK »

Coyote, the main CCI system and the SRIS are not connected in any way and basically have nothing to do with each other.
The SRIS is in place strictly to deal with the buildup of unburnt oil and gas left in the crank chamber after periods of idling.....especially during the first start of the day and/or starts in low ambient temps. The intention is to take that unburned oil/gas mixture and throw it into the next cylinder in the firing order while the next cylinder is on the intake cycle. This method supposedly promotes more complete mixing than would occur if the oil/gas mixture was just sucked up the tranfers of its own cylinder.
Does it work as advertised ?? Yes, in my experience.
Does it reduce visible smoke on acceleration after idling periods ?? Yes....just compare an H1 and a GT550 under the same conditions.
Does it reduce ACTUAL emissions ?? Partly.....although the quantity of oil and gas being burned is still the same, it just occurs differently than on a non-SRIS engine. A 5 gas analyzer could probably pick out the actual emission differences....but that's a moot point at this time.
Kawasaki actually picked up on this idea and its 74 and 75 H2's used a similar system in an effort to keep the EPA happy......if such a thing is/was possible. :wink:
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Post by Suzsmokeyallan »

Rick id like to see the effects of an SRIS equipped bike versus one with the system defeated, using a gas analyzer
In theory it seems the residual oil would be pumped into the other cylinders to be burnt, but it still gets burnt eventually so the amount of smoke produced from the residue wouldnt be reduced just shifted around till it gets burnt.
Two strokes, its just that simple.

69 Suz U70
69 Suz T500
72 Suz GT750 cafe
74 Suz TS250
74 Suz GTXVR project
75 Suz RE5
75 Suz GT750
76 Suz TS400
76 Suz GT750
81 Suz GSX1100
86 Suz RG500x2
88 Hon CR500
93 Hon CBR900RR
98 Suz GSF1200x3
15 Kaw Ninja H2
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Post by H2RICK »

Well, Allan, as mentioned in my post, the theory SEEMED to be that the SRIS would allow the unburned gas/oil mix in, say, the crank chamber of cylinder 1 to be more thoroughly mixed with the incoming "normal" mixture in the transfer ports of cylinder 2. Theoretically this would allow for more complete combustion and less smoke.....evn though the mixture in cylinder 2 would be somewhat richer overall than it would be normally.
Yep, it would be interesting to conduct an experiment with a gas analyzer as outlined in your post. Someday, when you and I are rich and famous and can afford a shop equipped with such an interesting tool we'll do a whole study on this esoteric subject and report our findings to the stroker world. :shock: 8) :lol:
GT550A Mint & Original
H2A Semi-Hot Rod Built From A Basket Case
KZ650C2 Mint & Original...mostly
GSF1200SK6 Bandit...My LD Ride
Additional H2 projects In Boxes.....
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