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Re: Problem installing BBK

Posted: Sun Jun 19, 2016 4:12 pm
by Wheelman-111
Greetings:

Thanks for the clarification B! Might be worth a trip to Turf & Irrigation or a store that carries a wide spectrum of O-rings to find one of the same diameter but a thinner cross-section.

Re: Problem installing BBK

Posted: Sun Jun 19, 2016 4:21 pm
by benji
On the same note, I ran the o ring that came w it for monthes and when I pulled it, it looked as tho it was just slightly too large to fit down snug and had marks that looked to me like it was off center. I do think sealing is important and using custom o rings may be necessary

I for one think a topic should be brought up about this. I have yet to figure out a definitive way too install these plugs as they don't come w instructions and seem to come w parts that are at best confusing to use. I've heard of glueing them in, bolting them in, just letting the o ring pressure-fit them in, all kinds of ways.

Re: Problem installing BBK

Posted: Sun Jun 19, 2016 4:26 pm
by FunkeyMonkey
Good info about the washer, i was trying to think of what i could use with the stock bolt hole to keep the plug held down. I hadn't really messed with the plug this weekend since i had so much trouble with the circlips but ill try some oil and see how it fits.

ps agree about the confusing part, i googled few youtube videos to make sure i wasnt missing something

Thanks

Re: Problem installing BBK

Posted: Sun Jun 19, 2016 5:16 pm
by benji
Image
Here's what mine looks like now. No big washer available so I used this small bracket. Big o ring off, only using o ring from oem pump.
Image
Here's what it looked like w the o ring it came w. Btw, this is an af05 from an aero not an af16 or af18, I don't know how those would fit but I assume it would be the same pump and plug footprint.

Re: Problem installing BBK

Posted: Fri Jul 01, 2016 9:33 am
by FunkeyMonkey
Getting ready to install the cylinder and just wanted to double check a few things to make sure i do this right.

#1. Should oil up the rings, piston and light coat in cylinder before assembling it. When torquing head bolts down piston should be in bottom position?

#2. Going premix, for break in im reading 30:1 or 32:1 in some old posts. Is this still current or anything different done these days?
Side note: Using GN2 oil currently, anything better or recommended for 72cc?

#3. Lastly for break-in, Ive read a mix of opinions on ride it hard or slow and easy. Just wanted to confirm what the best or most popular opinion is.
Heat cycle 10 times up to X? temp then let cool down to under 100F? Is this done on the stand at idle or giving any throttle?

I planned to heat cycle this weekend, then take the bike out for a few short rides around the neighborhood keeping under 30 for first 100 miles or so.

Any better suggestions or should this be ok

Thanks

Re: Problem installing BBK

Posted: Fri Jul 01, 2016 10:14 am
by benji
For the heat cycles I just fire it up and let it idle til it feels and smells warm. Old harley trick, put your finger on the motor case close to the piston. It should be too hot to touch for more than a second, then shut off until it's cold to the touch. (At your own risk, haha don't burn yourself)

Re: Problem installing BBK

Posted: Sun Jul 03, 2016 8:57 pm
by FunkeyMonkey
https://youtu.be/xvMh3US18Io Here's a clip of my first start up. Haven't tried tuning at all. Has a 110 main and 40 slow jet to start off, also forgot to set the carb screws so not sure how far off they are. The rpms are little high, i believe 1800 is idle? running in low 2ks. Ran it for about 5mins or so to warm it up little, tomorrow is tune day!

Man it's amazing what a little oil will do. Rubbed down the oil plug real good and it popped right in, didn't even need to hammer it. Picked up a 6mm bolt, lock washer and the big washer 1 1/4" i believe it was for $1 at home depot.
Oil Plug
Oil Plug
P_20160703_172548.jpg (151.92 KiB) Viewed 8531 times

Re: Problem installing BBK

Posted: Sun Jul 03, 2016 11:05 pm
by Meatball
Bottom is correct but screw it in till you run outta threads.

Re: Problem installing BBK

Posted: Mon Jul 04, 2016 1:26 pm
by benji
Ya, it looks a little low to me... are you using an o-ring ?

Re: Problem installing BBK

Posted: Mon Jul 04, 2016 3:10 pm
by FunkeyMonkey
Yes using the o ring it came with. Here's a closer pic. Didn't think it was a huge deal sitting just under the rim but if it is I can go back to home depot and grab another bolt and washer for a buck.

Re: Problem installing BBK

Posted: Mon Jul 04, 2016 7:56 pm
by benji
I would try slipping off the o ring it came w and using the one on your oil pump, see if it fits flusher. You might have a leak there. It doesn't look like it's sitting right to me.

Re: Problem installing BBK

Posted: Mon Jul 11, 2016 4:10 pm
by FunkeyMonkey
Thanks benji with oil pump ring it fits like a glove perfectly flush.

Re: Problem installing BBK

Posted: Mon Jul 11, 2016 4:42 pm
by FunkeyMonkey
So the break In seems to be going well, about a tank and 1/2 through of gas so far. Bike has great acceleration but of course still low top speed.

Looking at picking up gears and need some advice. I've heard 9:1 is perfect for 72cc but also seen talk of 8.44:1? I'm just looking for 45-50ish with decent take off speed. Also do I need to do a variator or clutch with gears or are gears alone fine?

Thanks

Re: Problem installing BBK

Posted: Mon Jul 11, 2016 10:12 pm
by benji
I would do the whole cvt/clutch/belt setup to aftermarket. I have a malossi multivar kit and a malossi fly clutch w bell, and I'm thinking of doing a zx rear pulley and gears, but the multivar got me to just under 45 w stock bore, a little better than 45 w a 65cc bore and haven't even got new rollers yet.

Re: Problem installing BBK

Posted: Tue Jul 12, 2016 9:27 am
by FunkeyMonkey
That's getting little more then what im wanting to spend. Ive already put quite a bit into the scooter and just trying to break that 30 mph barrier right now. I found gears for $50 and then i need to have the gear pressed on correct? Is the clutch or vari required to make the trans hold up to the new speed. I dont want to damage or break belts etc but I also dont want to spend an extra $100-$150 for maybe 5mph or little faster take off.

Thoughts?