DUM DUM BULLET

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Even looks faster!
 
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Compression test with air filter cover.
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And without.
I wasn't aiming for high compression but did expect a Higher reading than this.
Perhaps the Cam, anyhow I refilled with 95 Ron the bike runs really nice fx set to 7.
 
how does air filter cover have any influence on the compression??
also: you do have a modded head?
 
Let in more air that gets compressed as well?
Head is resized, Ports have been cleaned up and matched to the seats.
Combustion chamber is raised and Valves de shrouded, 2 base gaskets so a bit extra capacity.
Next week I will try to get it up Mt Greenmount in top gear holding the speed limit, couldn't do it last time I tried.
 
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This is how it is fitted for 411, I intend on just making it bigger when I fit the next larger Piston.
 
Updating, the 411 kit and Cam plus Fx pro performs well, it goes up Greenmount hill in top gear and has plenty of power.
Had it almost Dynoed but the Computer connected to the Dyno failed to boot up.
Now after sitting on my Butt for 6 weeks in Thailand I am back home so today I decided to get it ready to Dyno.
I decided I am not using the "special tools" that RE recommends, for a couple of reasons.
Firstly the Cam Holding tool is a piece of crap and is not as accurate as it is supposed because the locating pin is tapered where it contacts the Cam and is loose in the hole of tool as well.
I will post up a Video to show what I mean shortly.
And the TDC tool requires the clutch cover to be removed so as to set TDC accurately whist the Cam Tool lets its down by not being accurate, so why drop the oil, change a Gasket and perhaps have trouble setting the Clutch throw out.
I also decided not use the HMC Cam nor my modded head, so this build will be ,411 kit, decat pipe and airfilter cover removed only.
Stock muffler as is done on Hitchcock's J series Dyno ( stock vs stock plus Cam )
This should give a good indication of what the capacity increase gives in extra power and also will be the Cheapest option for any J series Owner.
Before strip down I did a compression test seeing 165psi, that would be due to the material removed from the combustion chamber and the 2 base gaskets I used.
So now it is 2 base gaskets and stock head and Cam I am expecting 190psi or more.
Here is the tool I made to insert thru the spark plug hole, it will create a physical stop at an exact point then I will rotate the other way till it hits the stop ( then remove the tool from the plug hole)halve the numbers and that will be TDC , timing wheel( wheel was too big and was going to involve removing the Gear shifter so it is not a wheel anymore!) is mounted to a 17mm single hex socket that has been bashed to make it a tight fit.
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I got cheap and reused the Head Gasket after painting it with Copper Gasket Paint, and this will be the 3rd time the Head bolts have been used so I may have a failure.
Start up tomorrow.
 
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Surprised that the Compression in this Build was just 165psi!
Not what I expected with the stock head.
Bike runs well, i shall take it up the Greenmount hill and see how it compares to the previous build.
Then off to the Dyno.
 
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