Modern Vespa

Greetings all. I acquired 2 kitted Small Frames (One 1965 Vespa 90 with Malossi kit and exhaust, One 1966 Blue Badge with Polini kit and exhaust). Neither currently run. Starting on the Blue Badge first.

Initial findings: Bike was built and never fully finished. Looks like it ran, but never dialed fully in. Bike has good spark. Carb is a new SHBC 19.19 98 main jet. Plug looks like it was not obviously rich or lean. Biggest issue seems to be an intake air leak, as the carb has electrical tape on the intake manifold joint. I am thinking parts are missing.

Questions: Is a 98 a good starting point for this combo? What parts are missing that would create a proper seal at the intake? Also, is there a trick to putting a new kickstart lever on?

Bike has sat since 2009, and the fuel system needs a full cleaning, and the petcock doesn't flow well, and needs at least a cleaning.

Any thoughts on this combo? Bike is really solid, and has new Bitubos front and real. Should be very peppy.

Thanks!
Rodger in Detroit

You need this for your carburetor

Take some photos of your bike for us. Take a shot of the manifold (looking down from where the gas tank should be) and then lay on the ground and take a pic where the manifold bolts onto the case (5 o'clock position of the engine if you were looking at it flywheel on).

I couldn't get the underside. Here is the view from under the seat.

So the manifold has the piece that choc said to buy so don't worry about buying anything. What you can do is get some RTV silicone and fill the slits in the carb and sleeve (thanks Voodoo for the idea). Then put a layer of grease over the carb where the electrical tape currently is. Mount and run.

The silicone and grease eliminate any air leaks at that junction. If you still have air leaks you're going to have to dig deeper but this is a good place to start.

To get the Kickstarter on, there should be some splines coming out of the engine around the 6 o'clock position. It's only about an inch long. Kickstarter goes on that and then is bolted tight! Don't kick it until that bolt is tight!

Silicone where the red marks are. Let that cure a bit, and then get rid of any excess that's smeared in there so only the slit is filled.

Thanks! Is a 98 a ballpark starting jet? Polini kit, pipe and 19.19 carb.

Seems a little high since a stock ET3 19.19 is only at a 76. Id probably start in the high 80s range and check temps/plug chops from there.

On my Special V5B3T installed 102cc DR, Polini Banana, 19.19 and air filter Malossi E4.
Now there is a 40 idle jet, the main jet is 88 and it runs very good, but I want to put the main jet less.
80 or 82, especially SIP recommends a 78-84 main fuel jet.

Under your scotch your carburetor is not broken ?

No not broken under the tape.

probably worth checking the intake from cylinder joint to carb, very common to find loose intake pipe. It involves blocking up the scooter, removing the rear shock to engine bolt and allowing the engine to swing down. their is a circular clip that engages the "sleeve to the intake pipe. If you orient it so the end gap is in line with one of the two tabs on the intake pipe it is simple to leave the bellows/sleeve assembled in the frame while lowering the engine with intake pipe away. I would keep the clip in that orientation. Then there is the debate about the the felt washer,lol.

I was planning on swinging the motor down to assess my options for the missing welded nut for the rear tank/seat post bolt. Both my bikes have that issue.

On the Blue badge there is none as the original saddle seat and valance had a bolt welded to the valance and a nut that attached it from the underside. I found some sort of threaded insert at the hardware store that I tapped out to use with the seat latch pin.

Do you have a pic?

No, Sorry.

Jet is actually an 86, not a 98. Going to start with that. Put a new inner clutch cable on, and cleaned the fuel tank and petcock. Carb is in the Chemdip pail now, and should be put back together in the AM.

Questions:
1. Any trick to putting a kick start lever on?
2. What oil and ratio do folks use? In my kitted mopeds I run Amsoil Sabre at 70:1.

1. See the image below. Lay down and find the quadrant splines on your scooter. Install the kickstart lever and then add the bolt. Tighten that down pretty good.

2. Any good motorcycle oil will work. 50:1 ratio. Lots of discussions on oil if you search through past threads

[quote="MJRally"]1. See the image below. Lay down and find the quadrant splines on your scooter. Install the kickstart lever and then add the bolt. Tighten that down pretty good.

Right now its on my bench. Looks like the lever hits the floor before the splines line up. Has a bitubo and I wonder if the motor is angled up due to the longer travel?

Not following you with the lever and splines not meshing. Can you post a pic of what youre dealing with.

As far as the rear shock, make sure it's a smallframe one. Longer shocks can be installed and not only will it mess with the angle of the motor, but it'll stress the rubber buffer at the top. Eventually the rubber breaks and the shock will come down rubbing your rear tire (happened to my friend).

For a quick fix if you don't require a seat latch, a 6-32 expansion nut, screw, washer, and 5/32(?)washer. Slip it in from above and tighten up

Alternately you could use a threadsert like the brass one pictured.I think it would work if the threads on the spike are long enough. You'd have to open up the hole in the frame and I'd use some JBWeld putty on the underside to secure it. You'd also have to drill and tap it to m7x1.00. I've done this on my other bike with a slightly different thread insert that is threaded on the OD. Both require drilling your frame and tapping the threadsert to M7x1.00(?) Both from the Hillman fastener section at Ace hardware.
*EDIT- Having seen now the video of how to install the threadsert, It should work fine if you drill and tap it after install, but you've kinda made using the original saddle/valance set up, you can't do it anymore without much effort. And you've drilled your frame. I have one that way and another I will not drill.

Thanks! That's what I will do.