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

RocketJ

RocketJ

Well-Known Member
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?
 
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.
 

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MotoMagz said:
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.
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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?
 
It runs fine. I put about 20000 miles on 212s this way.
 

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RocketJ said:
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?
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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.
 
MotoMagz said:
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.
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Hey moto, what are the dimensions of your engine stripped down? I forgot to ask earlier.
 
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.
 
waynesdata said:
What kind of frame is that? Very nice fork.
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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.
 
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
 
Tom from Rubicon said:
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
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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
 
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
 
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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