Medium Effort 85 Aero 50 2 Bolt AF05e Build

[nateberrier]

Hello.

I know this place is pretty dead, but someone is keeping it alive! (I would like to donate if that is helpful)

If any of the OGs are still around, probably remember I had a couple Aeros years ago, AF16 swapped one, got addicted to bikes. https://www.youtube.com/watch?v=sVDKO1UhWas Ive been doing all sorts of motorcycle stuff since then, and become a trusted mechanic in the community. It all started with my 1986 Aero

A friend asked if I could tune up his Sprees and get them going, and I have discovered a group of kids around here that build scoots and other small bore bikes! Had been asked to share some wisdom and sorta realized how much I missed having a scooter.

Another friend said he had two Aeros hes never done anything with, but he did buy Keli Variators with SEF plate and a technigas pipe for one. I picked them up cheap.




Panels are kinda beat with spraypaint, but the frame and engine on the one I am starting with are all in great shape. Tried to get it to run, but it was smoking out of the intake, and figured something was jammed in the reeds. The person who had it before him threw away the heat shrouds and mounted the coils to the shroud mount...........

I just decided to tear it down and do a build. When I started, I didnt know much about 2 strokes or bikes at all. I am WAY more comfortable with things now.


Im coming off the heels of a ground up build / restoration of a Kawasaki H1 500 https://www.youtube.com/shorts/UtYvLl6Uq_c Every last nut, bolt, gear, shim, wire, etc. Need to finish tuning it, but also ready to take a break and futz around. Those old triples are pure masochism to work on.



ANYWAY. I tore the 2 bolt AF05e apart, the cylinder looks to be in okay shape, bearings good, and judging by the overall condition, it probably is pretty low miles. There was a big hunk of rubber holding one of the reeds open, so it probably ran just fine. That said the stator side crank seal was leaking, so I feel justified in my full teardown






Heres a destroyed H1 piston next to the Malossi bore


I got the malossi head too


Wondering if I should try to drill out the holes for the bearing breathers or whatever you want to call them. I dont know what size hole they should be though, and I dont have an af16 or some other case to compare to. Would also have to figure out a way to hold it in the drill press.



I am going to try the technigas pipe and see how I like it but not sure about it. I would like to have a chamber. Im not a good welder, but I wouldnt mind cutting up a known useable pipe from an AF16 or something. I have a mutual connection with someone who is capable of the math for pipe dimensions.

Excited to have the Keli Var and SEF plate, that made such a huge improvement on my AF05s in the past.

I was going to make my own 2 bolt adapter but they seems to be cheap and readily available.

Picked up a stage 6 intake block, OKO 21 (usually I would go with a legit polini pwk but didnt seem to be available at this moment.) If its too big I can go to a 19 CP or something. Figure a chamber would be important to get enough rpms to justify the size of the carb.

Ordered some new KOYO 6203 and 6204 C3 clearance bearings for the crank. (much cheaper than using OEM P/N)

Today I am going to take the dremel to the intake and open that up a little + clean it up, and then match the ports to the base gasket.

[noiseguy]

Looks good. One of my inlaws had a Kaw 750 2 stroke. Wicked fast bikes.

[motormike]

Good to see you back in the saddle Nate. I'm still here, but not very much. My riding days are getting to be fewer every year. Had some health problems this year that have put me in a place that makes it tough to do anything. Can't work on my own bikes anymore. I am in Glasgow, KY now...think you may have known that. My riding buddy, Casey, and I have a group ride planned for Oct. 24. Casey runs the facebook page "Scooterarmy". You're invited to join us for the ride. Nothing expected too large, maybe 15-20 bikes. LMK if you're interested. I'll get you some info. motor.

[0U812]

Hey there Nate! This is Bonesv I had to get a new membership because some hacker or something was blocking me from signing in so I had to create a new identity to get back on here, but I remember you with the red Aero! You do some mighty fine wrenching and you have plenty of knowledge so I just wanna say that it's great news that you are back at it helping the local kids get their scooters amped up and whatnot! Now you have a new Aero to mess with as well.....and make it rideable like the other one. I imagine you weld just fine and should be able to turn an AF16 pipe into a AF05 pipe with some spare tubing and some hammering Looking forward to some pics when you get it done! Good to see you again! Thanks for the update also! Bones

[nateberrier]

Glad to see Motormike and Bones still at it. Like mentioned before, I am happy to support this place if I can, just need a paypal address or whatever!


Assembled engine



This bike seems to be overall in good condition and likely low miles, didnt stop someone from heehawing the wiring a bit and doing some other janky stuff. I have been recording to make a youtube video for this one.


I had always remembered hearing the Technigas Silent-pro or whatever fit poorly. It sure does. I cut it and re-welded to make it fit better. I found a rare chamber from Jazen (I believe spanish). I also ordered one from Buyee, so whenever their website is fixed, I can have it shipped to the US.

I also scored an old Italkit with the W shaped exhaust port + a parmakit crank for when this one blows up or i get bored and swap over.



Forgot to chamfer the ports and so decided to order new gaskets to be safe. When doing so I got a malossi Fly clutch and bell for good measure.

Did my first ride this evening. Petcock is toast so its basically on all the time, but wont stop me from testing it out.

I read a few places that the 21mm PWK would be too big for this engine, but I started with a 42 pilot and it was lean unless I ran the screw all the way in. I upped to a 45, and it is doing the same? Surely it doesn't want larger than a 45 idle jet?

Left the stock 105 main in, I suspect its pig rich. Will be checking it out later, but the goal is to just ride up to 2 stroke Tuesday. Need to order some Contra springs too.

So far it seems to get up to 40-45 without trouble. I have 7 grams in the variator but might stick 8 in there as that used to be the sweet spot for the af05 with a nonvariated pipe IIRC

Also short test ride yielded a loss of exhaust bolts haha


Heres a video of it scootin' https://youtube.com/shorts/vm_O0Qk85LM?feature=share

RPMs drop a bit up in the range, makes me think rich and/or needs a contra.

[nateberrier]

I thought I had posted the porting, but I guess I forgot that part!

I lined it up with some tape and sharpie and went as far as i thought i could without needing jb weld.

I did also open up the transfers a bit to match the bore. Nothing crazy but wanted to get what I could out of it. I also drilled out the breather holes for the bearings. For whatever reason those werent drilled on the AF05