Thinking of modding my 79cc

curtisfox

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May 13, 2010
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Ugh this is so frustrating I’m trying to adjust the dumb valves right now. It it now building pressure but the rockers automatically got sloppy and loose. I think you’re right about the spring as the rocker seems to put a light pressure on the valve at tdc when. I went down to .005 and it is pushing air out but the rockers are sloppy like I said. Maybe .004?
sounds to me like you are adjusting them, when on the up stroke of the push rods. And if you had the cam out, make sure the timing marks are lined up again..............Curt
 


Will'smotobikes19

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Apr 9, 2018
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Went to .004 and it has compression but are the rockers supposed to wiggle or have more space between the surface when not contacting the valve?
 

curtisfox

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Don't think so only .004, you got to make sure you on the down stroke when adjusting them.......Curt
 

curtisfox

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Just turn the motor till the valve is closed and and cam lobe is ope set of push rod, and has the most slack, or not touching, that is when you adjust the valve. If tdc. think it would be compression stroke. Don't remember, just make sure it is not opening or and push rod is on ope-set side of cam lobe, and not being pushed ..........Curt
 

Tom from Rubicon

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Feb 9, 2016
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Hi Will,
Performance comes at a cost I have discovered. Just got an email from AGK, They offer two levels of improvement.



I am leaning towards stage-2 as I have already got the 19mm Mikuni with custom intake manifold. Most of stage-2 is recommended by Pat Dolan especially decking the head down .050" to increase compression but he advised not using a non stock cam. Though he also said a high lift cam in a 212cc was a must do.
As to clutches/transmissions I like Bully that stays locked up for usable engine braking when set up by Sportsman Flyer, and EZ Q-matic and make a model for 79cc Preds. As Jerboa John mentioned 3D Motorsports is possible.
Tom from Rubicon
 

Will'smotobikes19

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Apr 9, 2018
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Yeah mine just has gov removed, ngk plug, stock 212 springs and I’m just trying to get the rockers to stop wiggling. Seems to get loose every time. I know there’s whole performance engines but I already have the motor.
 

mark20

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Sep 26, 2018
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437
Anyone have any idea how to make it so the rockers aren’t wiggling around.
well, if the rockers are supossed to "rock" around ;)
i think the predator 212 valve srpings are too short, i could be wrong.
try to put the stock springs back in and see if that fixes it.
 
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