I'm wondering about a tiny expansion chamber that would increase power at WOT. It might be fun to play with one.

I kept an old electric pressure washer around, because I'd like to try hydroforming with it. That would be a quick way to create a chamber.

Here's what Brian Solex has to say about expansion chambers on the solex engine. The last line is pretty good.
http://briansolex.free.fr/expansion.html
In fact, the whole subject of tuning the little mite is a good read. That said, watch this.
https://www.youtube.com/watch?v=ri42T8_6wHY

Well, that other approach didn't work too well.:ohno:

I bought the fancy HF plastic welder and succeeded in burning a hole through the throttle tube. Just like my first attempt at welding sheet metal in high school.:hehe: Into the experience pile with it.

Oh, well. New throttle tube will be here before the weekend.
:hi:

Kaaden's comments are theoretical. Bah.

I'd still like to see the results with an expansion chamber. if you want to try one, I have one designed for a 50cc China dirt bike that you're welcome to. It closely resembles the chamber from a Yamaha PW80.

That race was awesome! Hang in the turns, keep the revs up and pedal on the hills! Love it.

Sorry to hear that plastic welding didn't work out for you. I haven't tried the fancy welder, only the cheap HF unit.

Well, it was my first attempt with what is basically a high flow heat gun.

Thanks for the offer on the expansion chamber but I think I will these alone for now. That said, I bought a universal two stroke electronic ignition module for $12 just to see. Stay tuned.

Oh man thats good stuff seeing them pedaling. :clap:


/

How about some unnatural aspiration for the solex.
http://img4.hostingpics.net/pics/268823mobcust1.jpg

That's hilarious! :D

I wonder at what point is a motor simply not powerful enough to spin a compressor. I suppose if you could force it to start moving and it began to create boost, it would run. Theoretically.

Parts. From the guy in New York. He even threw in a headgasket gratis.
http://img.photobucket.com/albums/v4...ps3pvwqnpy.jpg
The black one now has a working compression release.

What is the device to the right of the track pad?

That is the throttle tube. Or as the Solex people call it, the slow down device.

Swapped out the headgasket, connected up the compression release, installed the new air filter. Went for a test ride. Woot. The little poop has some power now.

I'd love to see an action video, if you have the ability to record as you ride.

Three day weekend starting this afternoon and I have a Gorilla camera mount. I'll see what I can do.

I thought I had a Gorilla camera mount. I must have imagined it. Old age is a b*&ch. So, thank you, Amazon, one is on the way.

Installed the LED tail/brake light on the yellow one that should take a bit of a load off the lighting coils. Also found an E-10 base, white, 75 lumen LED that will make a dandy headlight bulb for the black one, if I ever find the rest of the headlight lens.

Yellow one is in a car show tomorrow evening.

At the car show.
http://img.photobucket.com/albums/v4...ps2chvyyw1.jpg

The owner of the Boss Mustang lives down the street from me. I spent most of the evening wandering the show. My neighbor said the bike was getting more interest than the Mustangs on either side of it.

A few more pics
http://img.photobucket.com/albums/v4...ps2ccji86k.jpg

http://img.photobucket.com/albums/v4...psv12jvztz.jpg

http://img.photobucket.com/albums/v4...ps8noafbrm.jpg

http://img.photobucket.com/albums/v4...psnp8fbmru.jpg

http://img.photobucket.com/albums/v4...ps38i0qej2.jpg

Thanks for the pics, Cheesy. I love that old flattie distributor.

It was a fun show. I even won a free oil change from the local Chevy dealer.

I had a few hours to kill this morning before hopping on another airplane, so I swapped out the failing condenser on the 4600. I replaced it with .22uf 1000v metalised polypropylene film cap, per the VS gurus.
http://img.photobucket.com/albums/v4...psu8kpcbf2.jpg

$10 plus shipping for the stock condenser of questionable quality vs $0.25 plus shipping for a MIL-SPEC cap. Hmmm, lemmee think a sec...

Anywho, it was an easy install just to see if it would work.
http://img.photobucket.com/albums/v4...psyenhhyez.jpg

It worked better than expected. Before, the 4600 would stall after 10 to 15 seconds at an idle. Quicker if I had the lights on. Now, after a full minute, it just putts happily away. Lights or no lights.

BTW-I fully intend to come up with a better way to get the cap installed. The gurus recommend stuffing it into the existing condenser can but not too sure this one will fit. We will see.

BTW, again, the tripod showed today, but I'm not there.

That's a cool mod. Reminds me of when the terminal on the "voltage regulator" on my TS185 broke; there was just enough terminal sticking out to probe it, and it turned out to be a diode. I repurposed a fat diode from a dead circuit board, soldered some male spades on it and plugged it in. It ran great, and I ended up selling it that way. The stock diodes are nearly unobtanium.

I gave up on the video today. Just couldn't get it uploaded. It also would have wasted three and a half minutes nobody'd get back. Will try again tomorrow.

I did have some luck with the condenser today, though. Here you go.
https://www.flickr.com/photos/214992...57658130737120

I think I understand...

Per the guru comment, you gutted the stock condenser and inserted the new cap. I'm guessing that the original condenser didn't have a stud on top; what was the concept behind that?

The stud holds both the + side of the cap and the original connector. I was going to solder the + side of the cap to the stock connector but figured that I'd end up being 75 degrees off on my orientation along with having the wire too short to do anything about it. So, everything positive goes through the stud, which is insulated from the can. Which means I can line everything up when I install it, then tighten it.

Very short video of Gordy riding the 4600.
http://vidmg.photobucket.com/albums/...psjy7jnrsx.mp4
Gordy is the outgoing prez of MACMC and he begged me to let him take the 4600 for a spin. BTW, today was the MACMC annual breakfast and just about everybody took that little bugger for a ride.

Some more shots.
Dave's Nimbus
http://img.photobucket.com/albums/v4...pscn9lswbu.jpg

A pair Guzzis
http://img.photobucket.com/albums/v4...psyjjw3zxk.jpg

A group shot.
http://img.photobucket.com/albums/v4...pstq1yqroc.jpg

So, I'm still somewhat stuffed from that breakfast. Then Mrs. C makes me a full blown Italian sub that, like an idiot, I eat. :ohno:I go out to change out the motor mounts in her Audi and am hit with the worst gas attack I've had in years.:wtf: Thought I was going to pop. And now she's making dinner. :doh:
All I want is bi-carb.

I agree, that is a short video. You're a big tease.

According to the MACMC site, it was a pancake breakfast at Gordon's Pumpkin Farm. Were there pumpkin pancakes? If so, I would have taken that as a personal challenge and eaten far too many.

Love the Nimbus!

Those Guzzi bikes are patterned after the venerable CX, right? :D

No pumpkin pancakes, thank you very much. I even think Gordon would draw the line there. Okay, I like 'em, but I only make 'em once a year for my granddaughter.

I'm watching all these people ride the little bugger around and forget I have the camera in my back pocket.:ohno: I remembered and got Gordy coming up his drive. He was the last guy to ride it.

As far as the Guzzis go, sure, why not. :shrug:Gordy has the V7 on the left and Joe has the Eldo 850. Joe is 76 years old and has seven Guzzis; from a post war Bacon Slicer to a fairly new 1400. He's riding down to Barbers' next month and I believe he is taking his California with the sidecar.

The guy who has the Nimbus, Dave, is in his early 80s'. I don't think he has a bike newer than 1960. :wtf:He was the guy who got Gordon to sponsor me in the club.

I'm working in N. Dakota this week, hopefully only for one day, then back home for a four day weekend. I'll try out the new cap in the 4600. Then, as I have wrapped up on the Audi,:yay: I will start on the stator swap on the CX.

The promised video. :shrug:

Watch, as the speed nears the triggering point of the flux capacitor.:wtf:

Listen, as the center stand drags on the driveway and halfway down the hill. :doh:

Cringe, as you hear me curse the hill I live on.:grr:

Alright, here it is.:hehe:
https://www.flickr.com/photos/214992...7656856002138/

Great video and just as you described.

/

I couldn't actually make out what you said, but I got the sentiment. :D Thanks for taking the time to share the video. I'm really enjoying this project, but you knew that.

Thanks.

In between the rain drops yesterday I threw together a Velosolex timing light. I got lucky on the 3800 and eyeballed that one perfectly. The 4600 has been a complete headache to get right.

The guts. Two AAA batteries, a green LED, and a 47 ohm resistor. For all intents and purposes, it's a continuity tester.
http://img.photobucket.com/albums/v4...psfodo2jfr.jpg

Off.
http://img.photobucket.com/albums/v4...pscrhe6j2f.jpg

On.
http://img.photobucket.com/albums/v4...pso6uqhrsf.jpg

For you young 'uns out there, the purpose is to set the points to start to open at the right time in cycle. I think I was off at least five degrees and now I'm dead on. Made a big difference.

I've static-timed VW engines in a similar fashion, but with a test light.

That's how it was done on my 64 MG, too.

Just to prove that I fail more often than not. Look at the red insulator.:doh:
http://img.photobucket.com/albums/v4...pszbkvpsu9.jpg

I've done exactly the same thing.

I was watching an old episode of Roadkill on Youtube last night, and Finnegan fabricated a lovely turbo manifold for an ugly 240Z with a 4.3l Chev engine. After he finished TIG welding it, he discovered that the collector flange was on the wrong side of the blow-off valve. Very funny!

I've done that quite a few times. ;)

Ah yes...the hard to kill Rotsun....

Last Saturday was Service Day on the 4600. Basically, clean, repack, and adjust the wheel bearings plus clean and grease the crankset. Standard bicycle type maintenance. I did this to the 3800 already and just got around to doing this one.
http://img.photobucket.com/albums/v4...psbemqogdd.jpg
The front wheel wasn't bad. The rear wheel, on the other hand, sheesh. I couldn't turn the axle by hand. Explains why the 3800 always felt faster. Anyway, done.

Used the old Harbor Freight chain breaker converted to a cotter press to service the bottom bracket.
http://img.photobucket.com/albums/v4...psgzg57ach.jpg
A very simple set up. Just a machined shaft riding on a pair of plain bearings. I followed another guru recommendation on future bottom bracket service. That was drilling and tapping a hole for an M6 zerk between the plain bearings. I should never need to take it apart again.

Finished up with a new 16 tooth freewheel and a new chain. All that is left to do on this one is either repair or replace the fuel tank.

When you say plain bearings, does that mean caged bearings, like one would find in a one piece bottom bracket?

i am guessing it means a soft metal alloy bearing, similar to a crank shaft bearing in a normal internal combustion engine.... hence the grease zerk... :tup:

Nope. Plain old bushing type bearings.

IOW, not ball bearings?

Not a one.

I spoke with my co-worker from France this week. He and I will be LA in a few weeks. When I asked what I owed him he just wanted a cold beer, or three. How can you go wrong?

That's the new commerce for me. IPA, preferably.