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The rebuilt 89 Is running on the oil pump with a small amount of oil mixed in the petrol, only 5l of fuel, once that's gone oil pump only, a bit of insurance while everything beds in .
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@oldman but you are running the stock cylinder?
@irongamer727 Iām pretty sure he is yes
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I'd run 1% extra for the first tank, then forget about it.
The stock pump supplies plenty, a bigger piston wont require more oil from the pump. The pump keeps the ratio up, so more gas = more oil.
The higher compression 170 piston should also "suck" more fuel, thus oil.I dont know when the athena kits camo out, but just about no one runs 3% theese days, with modern oil.
If youre really concerned, fill up the oil tank,and the fueltank. Note how much fuel you fill up with, on the next handfull of tanks. Then note how much oil is needed to top of the oil reservoir, and do the math and see how many % the oilpump has supplied.
When putting around, or riding at moderate speed, the pump fill supply under 2%, which is fine for that use.
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I'd run 1% extra for the first tank, then forget about it.
The stock pump supplies plenty, a bigger piston wont require more oil from the pump. The pump keeps the ratio up, so more gas = more oil.
The higher compression 170 piston should also "suck" more fuel, thus oil.I dont know when the athena kits camo out, but just about no one runs 3% theese days, with modern oil.
If youre really concerned, fill up the oil tank,and the fueltank. Note how much fuel you fill up with, on the next handfull of tanks. Then note how much oil is needed to top of the oil reservoir, and do the math and see how many % the oilpump has supplied.
When putting around, or riding at moderate speed, the pump fill supply under 2%, which is fine for that use.
@jens-eskildsen The pump is driven from the crank, I wouldn't have thought the vaccum generated from the engine would be sufficient to overcome the tight oil lines. I really don't know, but happy to be proven wrong.
For me, well, the later pumps are adjustable, so just knock the value up to increase the oil on idle, and everywhere else.
I would have thought the 170 would need more oil, since it's a greater surface area that you're trying to protect. So it makes sense that the bike would need a little more. But I know people who ran them and never had a problem. Ultimately, use good high quality oils and you should be fine.
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Oilpump is driven from both vakuum and the cables, So it will still supply oil at high revs, with throttle closed, like when the revs are dropping, and engine braking. Just about any 2-stroke oilpump will do this.
Yes, you have a larger surface area, but you still have the same ratio between oil and fuel, and the 170 kit needs more fuel, so it also gets more oil.
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Oilpump is driven from both vakuum and the cables, So it will still supply oil at high revs, with throttle closed, like when the revs are dropping, and engine braking. Just about any 2-stroke oilpump will do this.
Yes, you have a larger surface area, but you still have the same ratio between oil and fuel, and the 170 kit needs more fuel, so it also gets more oil.
@jens-eskildsen The pump is driven directly from the crankshaft?
The pump is affected via two means, throttle and the crankshaft.
So shutting the throttle off at high engine speeds, would result in the pump being driven purely by the crankshaft. But there will not be any load on the engine. Which is not the same as a vacuum.
I'm not saying you're wrong. I think there will be a vacuum draw, I just think it'll be really small. Hence why when the pump fails, the engine fails. The vacuum simply is not enough to go by.
I just don't want people to get the wrong idea. And maybe I am wrong, but I believe I'm err'ing on the side of caution here.
It's another reason why you should always blip the throttle when going down hill on two strokes.
Furthermore, the vacuum will be in part created by the mixture of explosive gases, when the throttle is shut off, you're reducing those gases. Ergo, the vacuum created will be much less. That's why turbo cars have negative air pressure on the gauges.
Note the gif starts from negative 30. So when the throttle is shut off, the gauge exhibits negative air pressure. I don't know what direction that'll be. Presumably sucking air? So maybe the vacuum is enough.
Again, definitely a discussion topic as I simply don't know to be honest. But just want to lay out potential scenarios.
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Roger, the point was that the oil is supplied, even when the throttle is closed. The jets supply fuel from the vakuum, and as more fuel is added, so is oil. Adding a bigger piston wont mess with the oil ratio.
Look at it this way, (eventhough im now scared to show examples) a 300cc 2 stroke runs on 2%, just like a125cc will, eventhough it has way more surface area. If anything, people will add more oil to a high screaming 125cc bike.
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Roger, the point was that the oil is supplied, even when the throttle is closed. The jets supply fuel from the vakuum, and as more fuel is added, so is oil. Adding a bigger piston wont mess with the oil ratio.
Look at it this way, (eventhough im now scared to show examples) a 300cc 2 stroke runs on 2%, just like a125cc will, eventhough it has way more surface area. If anything, people will add more oil to a high screaming 125cc bike.
@jens-eskildsen It consumes way more fuel and therefore delivers much more oil to the mix. Having had experience with the 170 kit, I wouldn't worry about the oil. They're solid motors and take a lot of abuse
