8 speed 79cc revival

xXNightRiderXx

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Jan 12, 2017
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Alright, I've got the stock carb back on my engine, gonna get new jets for it. Any suggestions? I need it running rich at idle, so it leans out as I gain speed because of my air filter. It faces forward and scoops more air in the faster I go, so I need to tune for my target speed.

I contacted agk about being able to buy their flywheel outside the stage kits. I'm also looking at buying their cam and head service. I might just forgo the cam though, I don't really need it.

I haven't talked to my dad about the oil pump system yet, so I'm not talkin about that.

I also finally got that 1" suspension fork I've been needing to get. I'm taking it to a shop soon to have the threads extended so the crown race seats this time. No shortcuts. Feeling quite sketched out now, with the fork wobbling fore and aft the way it is.

The stimulus package is arriving now, so I'm going to use that to do what I can to get this on the road. (^) Of course, that includes vin application, insurance, and registration.:confused:
 
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xXNightRiderXx

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Jan 12, 2017
430
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Boise
Alright, I got a response from AGK about the flywheel! Evidently, they have the flywheels being machined now, and they're waiting for them to be finished and shipped. They will have no waiting list. Here's the email I recieved:

The 79cc billet flywheels will be available very soon. We're waiting for the machine shop to finish them and ship them to us. We don't have a waiting list however we should have plenty in our first batch to go around. Thanks
 
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xXNightRiderXx

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Jan 12, 2017
430
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Boise
Ok, I got the fork threads extended, and the fork installed! She's ready to be test ridden now, minus the insurance and registration, and my own licensing... Gotta make sure I'm running rich enough to avoid running too lean at 40+ mph. Shouldn't be much of a problem with an 82 or 85 jet.

Found a billet flywheel for her from ARC Racing for $165. Gonna buy and install it ASAP. That should free up some HP.

It's also about time I drained out the break-in oil, added in my mobile 1 full synthetic, had an exhaust pipe made, and did a full port and polish. During this whole process, I will finally be removing the governor entirely.

I've been doing some extensive reading on how to perform all these tasks (minus the exhaust pipe welding). Still need to get my engine cc'd so I know my static compression ratio though. Once I know that, and figure out the point at which my intake valve closes ABDC, I can calculate my dynamic compression ratio and figure out just what octane I need, and set my ignition advance.

All these mods should get me up to 65mph maximum speed. If they don't though, I won't be disappointed. I'll still have a decent track bike once I pull off all the electronics and stuff. Before all that though, I'm gonna head to the High Desert Harley-Davidson and have my bike dyno'd.
 

xXNightRiderXx

Active Member
Jan 12, 2017
430
74
28
Boise
Just found out that each tooth on the crankshaft driving the cam is equal to 18°. I don't want to take my bike apart just yet to open the engine up, so if someone has a 79er already busted open who could check the intake valve closing point, that would be much appreciated. Gonna do a few calculations to find my static ratio.
 

xXNightRiderXx

Active Member
Jan 12, 2017
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Boise
Ok, I need some tools to do this. Please expect a delay between this post and the next while I take some measurements for an accurate static compression reading.
 

xXNightRiderXx

Active Member
Jan 12, 2017
430
74
28
Boise
Unrelated to previous post: I have reinstalled the stock valve cover. I noticed a definite increase in throttle response, and a slight increase in acceleration.

Related to previous post: I still have yet to acquire the tools required for reading my chamber size. This will have to wait a while.

In the meantime, I will focus on improving braking strength. It must be able to stop within 25ft from 20mph to comply with fmvss. First step: compressionless brake housing. Second step: caliper adjustment. Mechanically actuated hydraulics are more complicated to set up than I first thought, and compressionless housing is essential for maximum braking power.

Final step: set up a test station and repeat step two as necessary.