How far can I tip a 79cc predator past 90 degrees before it becomes an issue?

RocketJ

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Jun 20, 2018
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I know you can make a predator engine sit upright if you add a bit more oil, but how far can I move it past that upright position before there's a performance or oiling problem?
 

RocketJ

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Jun 20, 2018
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Check out this comparison. My buddy Racie35 turned a 212cc till the mounting plate was at about 105 degrees. I run mine cylinder straight up and down.
Hey moto,thanks for the comparison. The set up I'm thinking about would require the engine to be at around 110-115 degrees. Do you think that would be dangerous or would that end up returning the oiling to a proper level at that point?
 

MotoMagz

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Aug 2, 2010
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Hey moto,thanks for the comparison. The set up I'm thinking about would require the engine to be at around 110-115 degrees. Do you think that would be dangerous or would that end up returning the oiling to a proper level at that point?
As long as the dipper is in oil and slinging oil..you should be fine. I would get motor were it needs to be with side cover off and see what’s going on.
 

RocketJ

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Jun 20, 2018
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As long as the dipper is in oil and slinging oil..you should be fine. I would get motor were it needs to be with side cover off and see what’s going on.
sounds good. I'll see what I can do.
 

RocketJ

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Jun 20, 2018
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As long as the dipper is in oil and slinging oil..you should be fine. I would get motor were it needs to be with side cover off and see what’s going on.
Hey moto, what are the dimensions of your engine stripped down? I forgot to ask earlier.
 

MotoMagz

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Mine is a 212 is that ok? Also I shaved tank mounts time Tony01 did but I also shaved head and a lot of the casting around flywheel area. It’s cold!!!! I will get you dimensions later today.
 
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Tony01

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Nov 28, 2012
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What kind of frame is that? Very nice fork.
It started life as a ‘69 Yamaha ct1. Fork is stock ct1; I shortened the legs by 3”. Made my own dropouts for 10mm axle and disc mounts as well, to slim it down for 100mm OLD from the 12x125mm stock spacing. I had a thread “212 build heavy duty” but had to delete the content. I’ll be bringing it back soon.
 

Tom from Rubicon

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Apr 4, 2016
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Wonder if anyone did a SolidWorks rendering with fluid/oil splash and flow dynamics. Lower figure illustrates a greater oil splash than the stock position, and explain excessive breather output. Depressurizing the crankcase may be useful too.
1612242635807.png
 
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curtisfox

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Dec 29, 2008
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Wonder if anyone did a SolidWorks rendering with fluid/oil splash and flow dynamics. Lower figure illustrates a greater oil splash than the stock position, and explain excessive breather output. Depressurizing the crankcase may be useful too.
View attachment 106366
Interesting thought, would depend on where the dipper is, I know Sports car Pat says he added a bit of oil in the bigger engines. Almost have to take the side cover off to tell, what does AGK say?...........Curt
 
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Tom from Rubicon

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Curt, I don't know if AGK ever intended engines to be any other than stock configuration. I think the Misfit Board Tracker dude installed a sight glass in his engine case. using the #12 illustration one could scale it to a actual engine block to calculate a centerline. At present I am using two cups of oil per fill and getting minimum blow by.
Couple years ago someone posted a greater volume which blew out the rocker cover vent copiously.
Provided a perpetual grease slick. Coaster braking was exciting.
Tom
 

tokarev

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Mar 20, 2021
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We mounted the 212 vertical (original mounting base ) ran fine - we started with 18oz of oil. Video of the engine running at Dirtfoot Racing on YouTube
 

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