Modern Vespa

Hello!

I picked up a project '74 VBC and am in the process of tearing it down. Today I dropped the motor and under the carb I see some shady business. I cleaned the motor to make sure I wasn't seeing things, but it looks like someone, for some reason, used jbweld on the motor's carb intake and to the right of it.

I'm new to Vespas but otherwise pretty competent in motorcycle repair and mechanics, so I'll have no trouble tearing the motor down for an overhaul. I just need to know if I also need to do some mill work or, hopefully not, I have a catastrophic failure that someone tried to repair.

I need help identifying what could have happened here!

someone has mistreated this motor, that is for sure. is it from VN?

i can weld and mill, if that is something you want to pursue. lets make sure this is an American market bike before you make any journey on repair.

Barring the possibility that the VIN is totally bogus, would there be any VBCs from VN with a 1974 model year?

Jess, do you know how easy it is to make up a year when registering these things?

I could register a 1969 Vespa Primavera 190cc bike tomorrow in Vermont, when I really have a 1974 Vespa Primavera 125cc.

there is a magnitude off bad looking stuff in that photo. someone beat the cases with a hammer to open them instead of using the correct tool. The gasket surface between the cases are in poor; gasket used plus some type of liquid gasket.

i rarely see anything this bad in the US, that's why i asked if the motor is VN.

I was afraid of that. It looked pretty beat up like someone who didn't know what they were doing at all did what they could to get down the road.

It has a VIN and some Piaggio stamp on the swing arm. It has 8" tires and honestly the frame only has surface rust here and there but I have not stripped the paint yet so it could be pure bondo for all I know. The rear skirt around where the license plate is the worst, rust ate threw bolt hole and bottom of skirt looks ate up.

Other then that, inch for inch, it has seen MANY miles. As far as running condition, it kicked over first kick (no idea how) and ran down the street... no front brake cable and shiftier cables broke. It kicked in neutral and then I shut it off then bump started in second and it run out ok.

Fun times.

This is an American market bike that has been treated poorly. I'm in Vietnam right now and will be back in Indianapolis in a few weeks. I could have a go at it if you would like. something wrong with the cases anyways with that epoxy on it.

I forgot to mention, when I dropped the motor I noticed around the jug was what looked like metal wire wrapped around and pushed through a few levels of fins where one of the studs goes through.

It seemed just odd, like I have no idea what that even means. Just a rusty old thing gauge wire, almost looked like someone used it to hold something close to the motor maybe even away from the motor. NO IDEA

The VIN number looks to crisp and appears to have another number underneath (eyesight is not what it was).

Grumpy

Hey Thanks for the offer GickSpeed! I'm pretty good with a wrench and from what I've seen Vespa motors of this year range are really simple. I guess I'll find out when I crack the case open what kind of horrors are held within. Maybe I'll take a *crack* today.

Was thinking that too. Looks like maybe it was ground, filled, sanded, then restamped?

The numbers looked restamped (not the big issue here), but that intake rotary port looks to have been rebuilt/restored using JBWELD.. if that's the case, that won't last long and all is going to break loose and go through the engine.

Definietely take the engine apart, though you may be looking at replacing the cases... or... grind that stuff off and use a Reed Valve intake setup.

Ok so I saw that too so I just took a closer look and sure enough, there is another number under this VIN. NICE

Groover I may have to go that route if it is really that bad. But I guess the question is... how did it get that bad? You guys think someone detonated the motor and tried to fix her up? I guess where i go will be based off how the case looks like cracked apart.

Maybe I'll tackle that on my spare time today.

I'll keep yah posted and keep the idea's coming.

I think bearing failures are probably the most likely culprits when it comes to rotary valve damage. Sometimes piston wrist pin clips fail, and even the pistons. All those unfortunately get all tangled-up in the whirling forces of the vespa rotary valve engines leading to rotary valve damage.

There are some repair places that do it right (Al's?) where they actually weld/build-up the valve lip, then machine it back to correct tolerances.

The quick fix is the Reed Valve, and many love that setup as it cleans up idling issues, and many other issues tied to rotary valve (cranks cut too far up in the valve closing side for mod attempts, etc).

Of course, don't buy anything until you can see all that clearly once the case is split open to make that final call on how to proceed.

Did you buy this from the guy in Cumming that was selling a big lot of these a few months ago?

Hah, I saw that on CL a while back. Dude had a huge lot of them and wanted to offload it all. I picked it up from a really nice guy that I'm pretty sure bought from that guy.

I'm new to Vespas but not new to the game. I'll do what I can and send out if I need to. I'm not afraid of braking it down and doing some mill work or sending what i need to send out for welding (Wish I kept my miller Dialarc 250 HF). Its all cool, if need be I'll start looking for another motor or at least case.

I'm aware of that. But I can't think of any particular advantage to registering a 60's era bike as a 1974. In fact, I can think of a specific reason not to.

That bike is from Pakistan. I have had 4 in the shop and all had engines that needed to be thrown away. Only one of those customers was willing to pay for a new rebuilt engine in the bike but I made him sign a waiver saying that I said the bike was unsafe for street use. The frames were all twisted and covered in bondo and headsets were cracked and pourly welded. Those bikes are as bad a nammers, if not worse.

Yeah, agree. Usually it is the other way around.

Ouch. Glad I'm not in deep with it. So can you tell me how you know from photos or can you tell from comparing with what has come through your shop like same X and same Y over and over.

It would be helpful, thanks! I'd love to be in a Vespa I can ride but it seems that's a pipe dream here in the good old US of A. Should have stayed with Honda I guess!

BTW,

the 70's Piaggio Service manual describes repairing a worn/damaged rotary valve pad with the Euro version of JBWeld.

Possible, but if so it was done by a 10 thumbed orangutang with a wicked hangover and a serious banana habit.

Ok i tore the bike down, pretty easy actually. Here are the body parts, let me know what you think. Honestly it looks pretty straight front to back right side up and up side down. I'd have to break out a straight edge to be sure though. Head tube looked good, ball bearings still in the cages, etc.

I did notice janky stuff like nails holding stuff together. Still in the realm of "some kid who just wanted to keep riding" group. I've seen worse, much worse.

Oh and yes, the "speedometer" was just a cheap plastic piece with nothing behind it. WOW

If it was welded together then there must be an inch of paint on it, but the underside doesn't show it. Then again Vespa enthusiasts might be better off to tell me!

You're referring to the VIN but aren't the pictures I'm looking at showing the engine number?

Somebody cut a couple holes in the floor. Probably to fit a P-series rear brake pedal. Yay...



She's a rough one, but that's not to say it can't be sorted.

OK picked up a complete '78 VCB already taken apart and partially sand blasted. Owner found rust on the front leg guards and quit.

Much better looking front end, head stock, a real speedo, much better looking motor and, honestly, the frame did have more rust than mine but nothing that can't be fixed in my opinion.

I plan on going through the motor and seeing if its better then mine mechanically. At the very least (so far) I have found no JBWeld on the case.

I'll get some pics when I got some sunlight.

My question is... '78 vs. '74.... to my they look the same but I rather ask if using the best of these two is going to make the Vespa gods angry.

The best of which pile?

Ok got the VIN off the "new" motor.
Man that doesn't look like the first one at all does it? I'll clean it up tomorrow and see if this motor looks equally janky or not.

TCC, I just saw your post. I was talking about the motor the whole time, sorry for the confusion. We can't all buy new or hire mechanics every time your hands are threatened with dirt

lol. keep the pics coming.

Yeah. Looks like the guy went out and picked up a fresh Nammer engine to replace the Pakistani one.

Where's LynnB? Can't he offer some sensible advice?

Wow "this guy" huh? Did you include a doucebag thumb up and over your shoulder, maybe with a smirk? I appreciate your engagement and enrichment of this thread. Your addition to this thread has been very insightful! Thank You!

Mirror on vintage repost

Thanks jamesjohn I get it, didn't pay much for any of this so I'm not hurting.

I'll media blast the '74 down to metal and check it out. If its a patchwork then I'll just junk all of it.

It was fun getting in to it and obviously lesson learned the hard way.

Lesson learned everyone!

Great attitude brother! see what happens... I'm hope (not sure I'm all that confident, but hey! stranger things have happened) it doesn't turn out to fall in to the worste case scenario department! (did that make sense)
Anyway.. good luck, and please report you findings.. maybe there's a scoot to be had.. with some work..
Cheers.. and stay positive!

Media blasting will reveal the truth for sure. Some patch work is fine, depending where and how it was done. So far, it's not looking too out of norm, though I'm starting to see what looks like maybe some bondo filler below the horncast section (which would be behind the front fender area). It's either that, or the last time they sprayed the body they just sprayed over clumps of grease and dirt (and that would be in your favor!)

Looking forward to the next batch of photos.

Ahhh yes, I love the smell of bondo in the morning.... here are pics of the 'NAM. Body is sketchy, real sketchy. I understand why the guy stopped all work on the bike.

Other then that got some good parts that I need for the PAKI-SPECIAL. Looks like I got a hodgepodge of stuff. Headset looks like from a VLB but the speedo looks like a VBC. Why? Who knows, just glad I got a real speedo har har.

Cleaned up the motor and I got to say, it don't look bad at all honestly. Maybe a new flywheel but other then that I'll know more when I open the case.

FOR YOUR VIEWING PLEASURE:

I actually am kinda diggin the Vietnam sticker.

Try to save that.

Based on the foot peg things on the floor of the sandblasted bike, I think that bike was also from Panistan.

Sorry the sticker was a mspaint special, not real.

Aww, almost was hoping for one from 'NAM.

I'm going to cut a plastic 50gal drum in half, build a quick frame to hold it and fill it with water and baking soda. I'll drip the whole damn bike in there and do electrolysis for a while, maybe it'll boil up the paint with rust and I'll see where I'm at. I already gotta do two tanks and all the body panels, why not?

PAKI-Special well on its way. I need some cool Paki art to put on the side covers. Why not embrace the heritage? Maybe some Pakistan Henna or paint the thing like one of those Paki trucks.

Solid ideas... all of 'em... I'd love to see you follow the Pakistani paint idea.. there are pics on here of really good examples.. I'll try and find some..

Just for your Groover. Got the itch, grabbed a sanding disc and went at it. I hope I hit the right place! MAN that is ugly but I was expecting worse. Looks like, and i know this is a stretch of the imagination, that someone in good old PAKI replaced the floor boards and leg shields. Not professional but not actually 100% bad either.