Modern Vespa

I was given a free, seized ET2. I'm going to put the Malossi 70cc kit with multivar variator/clutch kit on it and use it as a beach scooter this summer. Ideally one would splurge for the 17mm carb but I was told the 12.5mm OG carb will work. Has anyone tried this? Any surprising results?

I'd start with the weber 12 TBH - I found the 17.5mm didn't get me much more with a simple cast iron kit (tried a few) and sport pipe, but was more finicky. Can always source the 17.5 later if you aren't happy with what you get out of the 12! The upshot to the 17.5 is it's easy to find jets and parts for it, though.

I tried a lot of things with my et2, actually, but it gets really gas hungry really fast with any modifications, which is disappointing. At the end of the day I have to say the stock et2 is a surprisingly capable scooter and I was never 100% happy with it in any of the modified configurations (but I suck at tuning as you know). If I were to do it again I think the sport pipe and small upjet with some fiddling with the variator is where I would have stopped with it

Check my signature for the setup I had on my ET2. It was rock-solid and zoomed up to 50 mph quickly. I miss that scoot!

If you want to get the full benefit of the 70cc kit you'd want to also upgrade the pipe but if you're just trying to beach cruise, it's not necessary.

Thank you for the replies. Did any of you try it with the stock pipe on? Obviously a free flowing exhaust will benefit things, but I'm curious if thats a need vs. a want.

I went pipe first and then cylinder, so I can't speak to how good the improvement would be with just the cylinder. However, I think Max at Motorsport (back in the day) said the gains are quite big with just the cylinder. I think because the stock exhaust isn't restricted in the US it breathes passably with the 70cc.

In your shoes, since it sounds like you only need the cylinder, I'd be tempted to try just the 70cc with stock carb and pipe and see if I was happy with it and only throw more money at it if not. The stock et2 really takes off pretty hard to begin with, so the bigger problem I had with the platform was the upper speed limit. I rode 2-up all the time in the city on my ET2 when it was stock and it was fine. It just wasn't good for higher speeds

Hopefully the 50cc exhaust is unrestricted. I know some other scooter brands built exhausts with a washer welded inside the pipe that would artificially restrict the exhaust gases. Easy enough to grind it out if thats the case. I'm away for a few weeks for work so I'm trying to order parts now, so boxes will be waiting for me on the 17th.

I really dont want a neck snapper. Just nice linear power with a higher top speed for riding around town. I'll put a surfboard rack and a milk crate on the back and ride the two miles to surf each day. Summer beach parking gets annoyingly tight from Memorial Day to Labor Day.

I believe US-spec ET2s came stock with the restrictor in the pipe. Mine was already taken out when I bought it but I don't believe it's a difficult task. There is a killer thread on ET2 tinkering by a user named Fabio that is worth taking a look at: My 50cc Challenge - ET2

Thanks for the link and thanks for the description in your signature! I read the first 3 pages and had to stop for work. Looks like basic gains with the kit and exhaust was a top speed increase to the low 40s.

Figured I could do just the top end and upjet for a break in, get the top speed, add the variator kit and get top speed. If I can get low 40s with just that, I'll leave it as is and live with it. I'm only riding back roads for errands. Nothing too crazy.

If I can't get my speed goal I'll splurge on the exhaust. On SIP, the Polini exhaust was only $100. Doubt I'll need the bigger carb for my goal but that can always be added down the line.

My 4 stroke Elite 80 does high 30s for me and that's fast enough around town. I've got my kitted scoots if I want to race around.


Sitting till I get back from work

I think you'll get into the low 40s easily with fairly minimal kitting. Some people hit close to 40 stock on them. They are about as powerful as a 125 Primavera after all. They weren't ever restricted in the US as far as I'm aware, but yeah you can derestrict the pipe easily if it is.

The thing I ran into is the top speed plateaus quickly because of the gearing and once you hit that point you can keep throwing kit at it and trashing the fuel economy without really making it much faster. For that reason I think your plan is smart of turning to the variator pretty early in the kitting if you don't like the speed. There's something degrading about riding a "50" cc that only gets 35mpg and you can watch the fuel needle drop when it is only 10mph faster than it was stock (and getting nearly double that economy)

If you are just beach cruising and don't want to piss people off use the stock pipe or a mild expansion like a Wild Lion. I was riding my SR50 with its expansion pipe by some shapes and an older gray haired woman flicked me the bird with a nasty face.

MJ- what year is your new ride? Looks similar to my 2002. Good Luck on your project.

If you take a look at the various 50cc 2T scooters out there, the 12mm carb is about the smallest used. One of the issues you have with a big bore kit is that the engine needs more gas and oil, not only to go, but to lubricate it and cool the top end. You can increase the size of the main jet, and it will work better, but it was about the minimum useable size for a 50cc scooter to begin with. A bigger carburetor will make a difference in how well the scooter operates, and for how long.
Piaggio went to a 17.5mm carb, even though they could still get 12mm carbs. Most of the Minarelli scooters came wtih 15-18mm carbs.
If you want the engine to last longer, go to 17.5 or even 19mm. People who know way more than I do about how to calculate the correct size caburetor for two stroke engines usually say 19mm is ideal for a 70cc big bore kit in an otherwise fairly stock setup.

As this is a 2T tuning thread, moved to Not-so-Modern, where the 2T experts lurk.

Thanks for the tip. 17.5mm carb for $90 isnt too bad. Product 4688/6418. Ive already got a full assortment of PHB jets thatll work.

I should just start riding my bike around town but what fun is that! Let me see what the monthly bills add up to first and then i'll start throwing more money at this thing

Or you could just sell all your other bikes and focus on this one.
If I can find the original site where someone really explained the two stroke carburetor size well, I'll post it.

Thats a good one!

I trust you on the size of the carb. Ive just never played the CVT tuning game. Not sure how the CVT affects engine load/ jetting.

the idea behind CVT tuning, and the reason it's not a one size fits all type of solution, is that you want to take the bike to the powerband and stay there while the bike accelerates. You don't want to go past it, and you don't want to be under it.
If you've ever ridden a big Honda four stroke scooter, and tried to open it up, you have a good idea of what it is like when the engine stays just under the powerband as the bike accelerates. The rpms slowly rise as the bike goes faster and it takes longer to get up to speed.
On the other hand, if you take a very high strung two stroke with a solid 8-9K powerband, and you're hitting 12K rpms and the bike is still speeding up, the bike has a feeling that it's falling on it's face.
Most of the time, when you tune a two stroke, the engine is more "pipey". The powerband is very obvious even with the seat of the pants dyno. If you accelerate with rpms that are too low, it bogs. So by using stiffer clutch springs, the three small ones, you raise the RPMS at which the clutch engages. So your bike is turning higher rpms before it takes off.
If you go too stiff, the motor races and the bike feels like it wants to shoot out from underneath you. Not enjoyable at the beach. Too light, and it absolutely sucks trying to start at the bottom of a hill and go to the top.
Contrary to what you can learn about being a scooter tuning expert on youtube, using a sharpie on your variator pulley to make sure the belt gets to the top and stays there, is a good way to kill your acceleration. By keeping the belt down, lower on the variator, for a longer time, you will have quicker acceleration. And that's what a heavier contra spring,the big one in the clutch does. It pushes back against the variator and keeps the belt in the "sweet spot" longer. Again, you don't want to start at the bottom of a hill and instantly go into high gear while climbing. You want the bike to be able to rev up and accelerate as it goes up the hill. The motor should be able to stay in the powerband while you are accelerating. So basically, you want the engine to be able to hold it's rpms when you have a load on it, like a hill in front of you, someone behind you, a surfboard, three cases of beer, all of the above, etc. That's where CVT tuning helps engine load. and higher engine speed allows the carb to suck in enough gas and oil to keep the top end cool when you are trying to get the bike to do something. In an ideal world, you won't have to flintstone up hills, but still have a very rideable bike around town and on the flats.
Based on what you want to do, changing the final drive gearing probably isn't a good idea, if you're close to the 405 and want to go to and from the beach. There's a bit of a hill.

The et2 autolube is independent of the carb size - and independently tunable. The 12 vs 17.5 carb will have zero bearing on adequate lubrication to the scooter. The 12mm is also perfectly capable of running rich on a 70cc kit. The choice of the 17.5 for the et2 is a matter of if it needs more air breathing ability. The 17.5 that came on the 50ccs (et2+typhoon) actually had a restricting plate to compensate for being on such a small motor

Those plates were to help restrict motor to 30mph in most cases. Where I live a 50cc scooter is legally limited to 30mph or you need motorcycle plates and license which I have. Removed all that crap, exhaust restriction carb restriction and spacer in variator on my Chinese 50cc scooter. It would go 40 mph a lot quicker for a 50cc motor. Mine was gear limited for top speed after that.

A lot of people don't understand or comprehend that a 50cc scooter can literally be speed limited because it can't turn a higher rpm. You can make it get to say 40 mph faster but it just can't go any faster. Mine would not go any faster no matter what I did until I put on a good exhaust pipe. It would get to 40 faster but was not gain any top end speed. I had a timing program I was using to see if changes were better worse or didn't do anything. Better pipe let me turn another 1000 rpm so my top end was faster.

Tuning variator helped with top end and take off. Follow the thread linked here it has a lot of good information and food for thought.

so when I worked at the dealer I did a metric ass tonne of these. 70 cast iron kit, 17, SP3 pipe and some rollers. if somebody wanted to get saucy a 19 with a vario.

on a stock carb and pipe you can get away with just bumping up on the needle clip position. but anything from there you'll need to upjet. and like Red said... if you're willing to come this far you might as well come a little farther.... throw a malossi red filter in the airbox and pop on a 19. any of the "stock style" exhausts Leo, malossi wild lion or technigas will work wonderfully. once you get into the expansion pipe zone then it's time to really rethink the carb/intake and dial in the jetting while messing with the trans stuff.

but for a runabout? I think you'd be fine and dandy with that mellow set up.

double check and adjust the oil pump, throw a new belt on that while you do rollers and a new belt and I think you'll be happy as clam at high tide!

When we had a shop, we used to be asked to derestrict 50cc scooters all the time. The first question I asked was, "does it go over 30?" If the answer is yes, it's not speed restricted, it's just slow.

Started Fathers Day off opening up the motor. Was blown away how crusty the belt area was at 1200 km. Take a look at the clutch bell!

Didn't find anything too wild at the piston or cylinder. Stock exhaust was de restricted and the new Wild Lion exhaust has a restrictor installed (WTF)!!

Clutch nut wouldn't come off for the life of me. Cut half of it off and then it came off with my fingers.

Monday I'll swing by Scooterwest and borrow some tools for the contra spring swap/ de restrict the Wild Lion/whatever else.




No head leak. Could still see the exhaust arrow on the piston crown.

I change contra springs on floor of garage. I sit on a stool, press down with both feet and put nut back on. Same process for taking it apart. A clutch tool for a large frame could work also.

As for exhaust is it a washer? If so take a picture, last one I did had one weld, stuck a large screwdriver inside twisted, snapped weld. Then clean up with whatever you have around.

Last edited by Christopher_55934 on Sun, 19 Jun 2022 15:20:17 +0000; edited 1 time

sames, on a 50 just throw your knees on it and bump the nut. install is same. or pinch it up in a vice nice and easy.

on the pipe, just punch that shizz out or use a Dremel/die grinder to get there and then some pliers. blow it out with some air and call it done.

btw, if you're keeping it injection? take a good look at the oil pump belt! quick, cheap and easy to replace now...

I need to buy parts/tires from Scooterwest anyway and they let me use their tools/tire machine. I'll deal with clutch tomorrow when I'm there. Figured i could have them look at it too in case there is wear/replace.

Definitely replacing oil pump belt/ hoses/ drive belt since it's open. While moving it, two stroke oil started pouring out of the cases. Not shitting you, maybe a cup. Now I'm wondering if the cases had flooded from sitting and there was really nothing wrong with the top end??

Exhaust plug was just a washer. Whacked on it for a minute but gave up as we have people coming over soon.


New Wild Lion

Look for tack weld or maybe welds and punch opposite side, you want it to twist.

Yep. There's just one weld on it. Stubborn bastard too. Will tackle more tomorrow.

Anybody know where these parts all go? I get the cable operated flip choke, but the rest I have no idea. Malossi engrish instructions include no mention of these. Just drilling 3 holes in the stock air box 🙄

Those came with the malossi kit? I don't recognize any of them - even the flip choke is different from the one I got for my 17.5 carb - don't see how this one would fit

Yep. 19mm Malossi carb kit.

Oh, stupid me - I'd missed that you went with a malossi carb. I was trying to figure out why those came with the cylinder kit (which they did not).

No idea (as is true about most aspects of my life )

Big thanks to Baumer18 for the explanation of things. Flip choke can get mounted in the belly somewhere with the supplied brackets. Two plastic hollow tubes are for air filter housing modifications on some model scooters (not ET2). Malossi instructions must only be able to be deciphered by Italians and Canadians .

Malossi instructions say to drill 3 holes in the outer air filter cover of mine if not already done. Mine has the 3 already so good to go.

Rebuilt the clutch using the white Multivar contra spring, yellow plastic torsion controller and yellow clutch springs. Malossi engrish graph on those says it engages at 4-6K rpms. Hopefully that's middle of the road performance for putting around town. Will install with a new clutch bell soon.

I tried to decipher the Malossi Multivar installation instructions for one of our club members and thought my head was gonna explode. You'd think pictures would be universally understandable but they find a way to make them cryptic too.

Looking forward to the results, I'm eager to go to a 70cc on my Typhoon(s). Also did you change the roller weights?

I will when I get to it. Trying to follow the Multivar instructions. Kit comes with 7.2g weights.

Comes with a plastic restrictor for the variator side. Robot said don't install it. Meant for places with speed laws or something.


#7

Yep those look like similar instructions and that washer (#7) was what had us scratching heads too. We left it out as well.

In Minnesota if it's registered as a moped it can't legally go faster than 30 mph. A moped also doesn't require a motorcycle license. If it goes faster than 30 mph supposed to be registered and licensed as a motorcycle and requires a motorcycle license. That washer keeps the pulley halves from closing together and pushing belt towards outside of pulley and going faster.

Like this one in new 28mph top speed.

https://www.motorcyclespecs.co.za/model/Vespa/Vespa%20ET2%2050%2001.htm

Yep. Made for all the Liquorcycle states/ countries. Kinda funny that performance parts that say not for street gives you that option to de tune it

Stayed up late and got her going. Flip choke I tucked away right side and somehow managed to lose one of the belt cover bolts. I guess that's better than having leftover hardware?

Installed an 84 main jet. Idles great but take off is too rich. Didn't hold wide open for very long since it's brand new. I definitely want to put a few heat cycles on it before I even try to ride. Not worth seizing the kit.

For some reason the oil pump won't prime. I can reverse fill the oil discharge line and it pumps that into the carb. Nothing comes from the pump though. Oil tank is full and brand new oil line. Not sure if the pumps air bound or maybe it's just slow from the tap? I'll let it sit overnight and see if that helps prime the feed line. Gas tank is all premix for the time being.




New home for the choke cable



Wild Lion sounds just as loud as stock. Maybe a hair louder

Let it idle some more while I was cleaning tools. Oils definitely coming, but coming in spurts. Lots of bubbles in the line and then a solid stream. Rev it up and the bubbles come back.

Bad pump?

Morning restart. Is better, but still introducing air. Definitely leaning towards an oil pump failure causing the original problem. New oil pump is $30.

Compared the clutch engagement to my wife's Buddy and I'm gonna swap to the white springs. This thing needs to be revved up way too high before the wheel turns. Gonna be annoying as a beach scoot if the rear wheel doesn't turn when I twist the throttle.


Cold start

10 minutes later. Still introducing air