Modern Vespa

OK, I have the old nasty belt off, am covered in grease, and am now trying to reassemble the new belt, clutch and variator back together again. While I was taking it apart I had my wife snapping pictures to help me with reassembly in case I got stuck. Well, without getting into too much detail, I have a bunch of blurry pictures, and am now wondering which washer goes where, etc. Any pics or drawings of washer locations would be helpful.

On one of the tech articles it says to torque the front variator nut to 59 - 62 ft pounds. I bought a torque wrench that is in inch pounds. I calculated it out and round it off to 60 ft pounds, which would require 720 inch pounds...... (720"/12= 60') Is this right? I don't want to be snapping anything off.

I am going to use 40 foot pounds for the clutch nut, but again, that looks like 480 inch pounds. Is that right?

I have a clutch holding tool and a variator tool. Both are Buzzetti brand.
When I am torqueing the variator bolt with the Buzzetti toll locked in place, the entire crank shaft is turning, which won't allow the nut to torque. The variator is locked and not moving, but the back area where the rollers are is moving. How do I stop this from happening?

Thanks ahead of time.

This may help:

https://modernvespa.com/forum/topic20467

Yes, multiplying pound-inches x 12 = pound-feet, so your calculations are correct.

Now as far as your shaft turning--this is very bad. The outer variator half splines onto the shaft, so if it is on correctly, locking its position will lock the crankshaft.

Take everything apart. Make sure no part of the pulleys is greasy--everything should be clean and oil or grease free.

First, put together the inside variator pulley, rollers, backing plate together as a unit. Insert the bushing into the assembly from the pulley side and slide the whole thing onto the shaft.

Now place the washer that was next to the bushing on the shaft.

Next, place the belt into the clutch side pulleys. Get a helper. Put the assembly down on a piece of wood or cloth with the clutch down. Remember to check the orientation of the belt. It rotates in one direction--there should be arrows.

Push the lower pulley down towards the clutch and have your helper shove the belt as deep into the pulleys as possible. This is critical. If you don't do this, you won't be able to put the outer variator deeply enough onto the shaft and you will wreck your bike.

Slide this assembly onto the driven shaft, making sure the belt doesn't slip out--it needs to be in deep. Set the front of the belt over the front shaft.

Now slide the outer variator half as deep onto the shaft as you can. Make sure it isn't catching on the belt. You may need to wiggle as it must spline onto the shaft.

Now, add the two washers (bigger one on the inside) and your nut.

Engage the holding tool (make sure it's tight, the Buzzetti works well, but it relies on the bolt to keep it engaged).

Now you should be able to torque everything down.

Put a spot of paint or nail polish on the nut and shaft.

Put everything together (except for the transmission air filter foam).

Don't forget the clutch bell. Torque down the rear shaft.

Run the engine, rev it a few times. Stop it and look at the nut and shaft through the big hole you left open at the transmission air filter. This will tell you if the nut is holding its torque. If it slipped you'll see the paint cracked and misaligned.

Cover your bike, go inside and have a beer. You're done.

P.

Thanks for the help. I actually called www.scooterwest.com to get help since they had sold me the Buzetti tools, and those guys pulled a diagram and helped walk me through it. Big props to them, because they basically held on the line and listened to me curse for 30 minutes.

Basically, I had the large flat washer all the way against the back of the drive line, and it goes on the inner face of the outer variator part with the fins.

The Buzetti variator tool is pretty finicky. If you don't have the screw with the allen head lined up and torqued in all of the way, the variator can move. It's really hard to see if it is lined up and screwing in right because of the barrel shroud that goes around the screw, and I had the beginnings of a cross-thread going before I caught it and corrected it. I will carry extra screws with that tool from now on.

Once I had it all figured out, it was not that hard, but it would definitely suck having to do this on the side of the road with a hot bike during the Cannonball.

Observations:

I am definitely getting a couple of grooves in my variator faces from long highway riding. I got a lot of crud off with brake cleaner, but there are still grooves starting. At some point I will do a variator upgrade, or go to a new stock unit.

I started it up and it ran fine up to 55 mph on a short ride. I switched to new (stock) rollers, but it feels quicker off the line. Probably because there is less crud in there for the rollers to resist against.

My scooter is louder than before. Right before my belt went I was at a rest stop and commented to my wife that the exhaust note sounded louder. The belt broke soon after that, but I am not sure they are related. Maybe I have a gasket that has gone bad, because the noise is coming from right under the scooter when I rode it again, and not out the back of the muffler as before. It's not super loud, but definitely does not sound stock anymore.

What should I be looking for about that? I checked the gasket near the muffler and it looks OK. This sounds like it is up closer to the exhaust manifold. Anyone who has a diagram, please help me isolate this new development.

Again, it still runs great with the burble, and doesn't sound like anything is wrong with the engine, just a different exhaust note.

Thanks again guys, and thanks to Scooter West guys.

Sounds like the header is cracking - it will get louder as the crack gets worse based on what I heard happen realtime following a friend's GTV.

Btw, I had one unexpected problem that took me nearly an hour to solve. When the belt disintegrated, a lot of the long strands got wrapped around the clutch. I kept unwrapping the threads, which are made of pretty stern stuff (probably kevlar), when it became apparent that some of the threads were not going to come undone, as they were some how wrapped underneath the clutch plates. As you know, that spring that holds those plates apart is pretty thick. I stood on the top of it to try and compress it and it would not even budge.

What I eventually did was cut two 1"x4" boards that I could wedge into the middle of the plates, and then a stood on them to force the plates apart while my wife unwound the remaining threads that were stuck. It was pretty good duct tape and snot engineering on the spot. I don't know what the normal way to compress the clutch plates is, but this worked.

That sounds $.

What is the best was to see the header, from through the top, or from underneath?

Is their any kind a air sensor downstream on the header?

Yes, it did. Especially without a 19mm, and all your tools in the support truck.

BTW, I'd actually say 44 ft/lbs...

The header is in the $150USD ballpark I believe. Karman is the one it happened to but it was under warranty. Yes, there is a sensor that plugs into the header but I am told it just unplugs and plugs in (I have not had to do this yet). Look at if from underneath and maybe run your fingers around the seams and see if you can feel a crack. Anyone that has actually done this should be better help than me from this point.

That's the lambda sensor, which feeds back to your ECU to adjust your air/fuel mix. It doesn't quite plug in/out but, for all intents and purposes, it's pretty simple to remove.

Cracked headers aren't terribly uncommon... one oslution is to get a one piece pipe like the PM68.

I woud have NEVER thought to carry a 19mm before today. Now I know I need from 8mm all the way to 19mm, so I may as well build a trailor and tow a set of Snap-Ons .... just in case.

Yeah, I have a wideband air-fuel on my exhaust on my supercharged Miata.

If I do have a header crack I would be getting too much air as a reading, and the computer would have me running rich... probably.

don't think you need a 15 or a 16 for anything.

Honestly, I really don't carry those types of tools with me, more or less ever, cos it's just not practical or necessary. Drive train failures are pretty rare... and there's a point where it's just not worth prepping for it considering you can just get a tow.

Only time I carry stuff like that is for long distance trips...

depends on where. Might not even catch it, might be behind the lambda sensor, and then I think you'll just be missing back pressure.

Here's the Dealer Service instructions on replacing the old style header for the upgraded part, it has the most detailed pics of the stock exhaust setup-
[url]www.semenoff.org/vespa/GTSExhaustRecall.pdf[/url]


With a cold engine you can start up the scooter and feel around the gasket/header area for escaping exhaust gases to locate the source of your leak (you have 10-20 sec before it's hot enough to give you a burn).

Good luck with it!

Thanks Harvey!

My last two rides have been 1150 and 600 miles, so I probably do need to be prepared, especially when I am up in the 7k mileage range.

You're welcome. I just had to replace that frickin' gasket today, so it was handy.

How many miles a day?

that's the real determiner. Long mile days (350+) break down belts - these belts die from extended exposure to heat. One way to help this is to open up some of hte air flow going into the transmission case...

I did 1k mil in a weekend without thinking about my belt. But were I to do 400 in a day, I'd be more cautious.

Also, if you run long days, I'd change a belt earlier than the recommended interval.

I tend to always replace belts at 6k mi.

300 miles over 2 days down to Key West.

300 miles in one day back from Key West.

700 miles up to Banner Elk in one day.

Approx 450 miles on the way back from Virginia when the belt gave way. That was a hot day too.

All told, 1150 miles over 36 hours.