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Sorry I'm late! I didn't know we were talking about piston conversions!! Ha. I still do a bunch of iron barrel 186cc tunes. I prefer not to shorten the cylinders these days, but its still a good optio

YO!!! UPDATE!!!! IT RUNS!!!!!!!!!!!!!!!!!!!!!  I got it running today 4/26/2020!!  The first time this LI has fired since I bought it back in 2017.  It was a basket case back then. Here are

Thanks for sharing this info.  Obviously others have questions and this might help others.  I'll look into what you suggested because right now I have no clue what your talking about.  But I will soon

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Hello, Happy Thanksgiving to you (in the States) and Happy November 28th to everyone else.

Time fly's and 7 months have slid by in a blink of an eye.  Much has happened over the course of these past months.  I managed to get some things done to my Lambretta LI125 project (images below)

I need help locating an exhaust for my project.  
LI125 S3 - with a Mugello 200 cylinder.  Standard exhaust flange.  I'll ride this scooter in the city 80% of the time.  Highway 20% of the time.  There are plenty of hills in the Pacific Northwest.  The bridges between the state of Oregon and Washington cross over the Columbia river, these bridges are 55-65 MPH highways.  So my target is to have enough power and spunk to get up to speed and cross these things without issue.  If you need more info, please ask.  

Thanks for reading... I've been rubbish at reading your threads. 


I installed longer studs into my case.  There were a few holes which were partly stripped out.  I chased the threads clear to the bottom and cleaned them all very well.  Then I installed these great studs in with a drop of medium thread lock.


Here it is, looking good.


I also found some stainless steel nylock nuts with a broad shoulder.  I think these are much more secure than the wavy washer set up.


I bought a heating plate to try my hand at installing a bearing with heat.  The trick worked SO GREAT!!!  


If you know who these two guys are, then you are my kind of people!!!


Installing the output shaft and all that stuff.


My first transmission job ever.  Such a cool set up.  Now I know whats going on down there.  I played with this for some time.  Very cool how it all works.


Here is my big gear.  There are a few chunks missing from of the kick start teeth, but I didn't see a reason to get a new one.


End plate installed.


Heat plat trick again, to install the mag housing bearing.  Once again it was a slam dunk.


All sealed up.  With an internal note of who and when this motor was rebuilt.


Crankshaft in.  This is my first 2 stroke motor build.  Its so different from a car motor. 


Mag housing installed.  All new hardware used throughout this build.  All threaded holes were chased and cleaned.


Output shaft sprocket installed.


Getting ready to install the clutch drum.




Clutch disks soaked in oil overnight.


Compressed and retaining ring installed.


New SIP chain tensioner .  Looks weird but I guess it works.


New piston, came with the Mugello 200 cylinder.


New barrel studs.  These are just a bit longer than stock, just to give me a bit more thread to use.


LTH reed intake housing installed.  Had to remove some meat from the cylinder fins in order for this to fit.


This was a fun project.  I think I gave enough space so that nothing will rattle even when the motor is hot, but we'll see.


Final shot, just a different perspective of the fins that had to be altered for this intake to fit.

Thanks for looking.  More photos to come.  Take care.


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I just saw some pics of other motor builds and realized that I did not install my chain tenssioner correctly.

I put the chain over the top, but I guess that the chain goes along the underside.  I'll have to swap that before I go for my first ride.

Thanks LCUSA for posting good pics.  

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4 hours ago, Stu aka S.Hanson #17 said:

Very cool. Looks great! Chain tensioner can be run with chain on top or bottom. Just depends on the chain length and sprockets.

Stu Aka S. Hanson!!!  Thanks for the info boss, I was just about to crack the case open.  Come to think of it, I dont think my chain had enough slack in it for it to fit under the tensioner.  When I first installed it this item I was surprised that it came with no destructions.  I didn't find much about it online either, so I just guessed.

Once I do get this on the road, I'll pay attention to the case.


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9 hours ago, Stu aka S.Hanson #17 said:

Are the shouldered nylock nuts you are using designed to be used without a washer? I'd like to use a similar set up. Never saw anyone else use them and want to make sure I am using them what they where designed for. 

The flange nuts I used could be used with or without a washer.  I guess that it comes down to personal experience. I'm sure there will be someone out there who thinks a washer should be used in all cases.  And if I hear a good argument for adding washers to my set up I'll do it.  My understanding is that a flanged nut does not need a washer, because the flange is distributing the pressure across a large area, which is what a washer does.  These flanged nuts have a smooth face like a regular washer.  I've had good luck with flanged nylock nuts in the past.

I got all of this hardware online at BELMETRIC.COM.  This website has all the metric hardware you'd ever need.  They are affordable and ship fast and accurate.  I was very impressed with them.  My local hardware store has a good selection of the standard metric stuff, but when it comes to 7MM I had to find a source.  I think that Bel Metric is a great resource.  Check them out when you get a chance.

Cheers 🍻

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QUESTION:  Do I need a head gasket.

I have the Mugello 200 cylinder.  I can not find the head gasket.  I dont think the kit came with one.  When I search that product out, the photos do not show a head gasket, although other gaskets are included in the kit.

Any info would be appreciated.

Cheers. 🍺

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I found out that the Mugello kit does not come with a head gasket and seems to not require one.  I guess that the crush measurement will determin if you need a head gasket and what kind you need.

I tried the crush test and could not get any crush what so ever.  Is this odd?  If I get no crush is this bad?

Here is what I found on Facebook, in relation to the head gasket.

"All new kits are supplied with a seven stud fixing (three additional studs, nuts and washers, to ensure consistency in head location.  The three studs should be fitted to the cylinder.   All the newest version of the kits do not use head gaskets.  You can tell this by checking your cylinder head.  If this sits into the cylinder, no gasket is needed except where you need to achieve the correct squish clearance (working clearance between the piston crown and cylinder head; necessary for efficient running of the engine). We highly recommend a very thin smear of Threebond sealant where a head gasket is not used.  When fitting your cylinder head, it should then be secured by strong plain M8 washers, followed ideally by our extra length M8 cylinder nuts (including the elongated nut for the purposes of securing the head cowling and as referred to previously).     "                


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  • 2 months later...

2020 UPDATE:

Its a new year and I believe that I'll have this Lambretta up and running by the spring.

Here are a few things that have been accomplished over the winter so far.


I bought two sets of levers, but each one seemed to be a bit worn out.  I didnt like the slop that I felt.  So I built some brass bushings out of hobby brass tube.




I also installed the spring / plastic bushing set that keeps the lever from rattling to death.


The motor is back in and things are getting put back into their proper place.


This scooter was a basket case when I got it.  Most the important stuff was removed or dissembled.  So its been fun putting things back together.  


Each time I move onto a new task I discover that I'm missing parts.  Little stuff, grommets, cable ends, hardware and so much more.  I've also learned that certain things need to installed in a particular order. Some of the time I've spent in the shop has been undoing the things I'd just done, because I needed to install something else first.  


This is the hands on project I had hoped for.  I'm really getting to know every inch of this machine.  I've also aquired lots of tools just for Lambrettas. Next build will go a bit quicker.  And the next scooter I buy I'll know what to look for.



Thanks for checking in.  


If you're ever in Portland, let me know, we'll go grab a pint at McMenamins.  Cheers.


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Once I got my cabels installed, I discovered that my front break was not working.  It was stuck.

I took things apart and discovered some mega rust at the pivot studs.  The leading shoe took me a few days to get off.  The steel and aluminum had formed a bond that was really secure.  I cleaned it all up and now I have some good acting breaks.




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My latest snag has to do with my throttle cable.  It seems that it isnt long enough. My cables are brand new. I bought the standard combo kit for Lambretta 125-200. Sounded like they would be universal.  But my throttle cable is about 3" too short. (keep your wise cracks to yourself 😜  ).  My old cable is trash.  It's frayed and kinked.  The outer cover measures 5'.  The inner cable is 5'6"  I measured the amount of cable I'd need for my carb and 5'6" is my closest guess.  

Currently, when I try to fish my cable end into the carb, my cable end is barely long enough to enter the carb body.  It needs an aditional 3" to reach the slide.

How do you folks choose the right length for your scooters?

Thanks for your help.


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Any chance there’s a cable routing problem?  I’ve always had extra inches/slack when installing new throttle inner/outers.  I’ll be curious to see what response you get after folks measure what they have laying around and get back to this thread.  I don’t have a new outer handy, otherwise check it out. 

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3 minutes ago, ScottWally said:

Any chance there’s a cable touting problem?  I’ve always had extra inches/slack when installing new throttle inner/outers.  I’ll be curious to see what response you get after folks measure what they have laying around and get back to this thread.  I don’t have a new outer handy, otherwise check it out. 

My guess, no.  The reason I say that is ... The outer easily stretches from the upper perch down to the carburetor perch.  Its the inner cable that isn't reaching deep enough in the carburetor to reach the slide.  

I've just visited a scooter site, and found Extra Long inner cables. For now I think that I'm going to go that route.  However, I am still interested in knowing how to properly purchase / install the throttle cable.

Thanks for your reply Scott!!  I'll send you a 4 pack of McMenamin's Hammer Head Ale if your interested??  

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I always love reading these build threads - whether they're from a first time builder or a seasoned professional. Keep the updates coming!

In regards to your question about throttle cable lengths, I've found that most aftermarket carburetors require a longer throttle cable than stock. I say most, as a TM24 with a Dell'Orto 90 degree elbow threaded into the top will work with a standard cable, but I'm yet to find any others. A number of dealers carry longer cables, or you can make them yourself.

Also a fan of Belmetric. Simple to use (can search by DIN number) and fast delivery. Very welcome in country that insists on using antiquated forms of measurement :)

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16 hours ago, Roger Hudnut said:

My guess, no.  The reason I say that is ... The outer easily stretches from the upper perch down to the carburetor perch.  Its the inner cable that isn't reaching deep enough in the carburetor to reach the slide.  

I've just visited a scooter site, and found Extra Long inner cables. For now I think that I'm going to go that route.  However, I am still interested in knowing how to properly purchase / install the throttle cable.

Thanks for your reply Scott!!  I'll send you a 4 pack of McMenamin's Hammer Head Ale if your interested??  

You’re more than welcome.  No beer mailing needed, but I’d be glad to share one at a future Jammy with you.  Continued good luck with the build.

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  • 4 weeks later...
On 2/17/2020 at 11:57 AM, Mike Anhalt said:

reading over the thread and spotted something potentially bad. Did you install the flywheel bearing race before putting the mag flange in place?

Mike, Yes, that bearing race is installed.  Stickys book doesnt really flow like a Chiltons or Hanes.  That specific step isnt mentioned in the book from what I could see.  However, I spotted the issue and fixed it.  Caused a few extra steps, but none the worse for wear.  Thank you for paying attention!!  

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I've just posted a HELP!! thread in the Technical Advice Section titled Varitronic Install.

If you can assist me, please check it out. I'm a bit confused on which of the red wires goes to terminal number 1 on the coil.



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Here is an update:

I've been busy. Here are some pics of things that I actually took pics of.



New treads!!


Voltage regulator and coil mounted and nearly wired up. Just waiting for reply on my request for help on my new thread.


Carb is in but giving me fits with the cables I bought. My throttle cable was too short, but the outer case was the correct length. So I bought a longer inner cable and a trunnion.

The choke cable it too short too.  Turns out the inner cable is the correct length but the outer housing is too long?? I've got one coming, we'll see how it works.


I'm only getting this much inner cable.  The carb needs twice the length.  I'll post a pic like this once it arrives ... if I remember.


Dont worry about that old crust ground cable you see hanging there.  That has been cleaned up too.

More to come soon!!

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My choke cable showed up today...but it is not going to work either. I need some help identifying which choke cable I need.  I've take some photos of my two cable options.  The inner cable seems to be correct, its the outer sheath that is either too long or too short.


In this pic you can see that I have two choke cable lengths.  The inner cables are the same length. Its the outer sheath that is different.

The longer sheath is what I got from a typical LI125 Series 3 cable kit. I cant use it,  because the length of inner cable is not long enough to reach the choke piston.

The second cable I received is intended for a carb with and elbow. I assumed that would work, but it is too short of an outer sheath. The inner cable is too long for this application.


as you can see, the cable for the Elbow is about 13.5 inches long and the other cable is about 15.75 inches long.

What cable do you guys use???


Here is the inner workings of the Dellorto carb choke section.  This carb does not use an elbow.


Here is a pic of the carb and the choke section.

Also, I have a question about what type of hose goes on the following nipples?  What are these for?


I know what the large barbed nipple is for, fuel into the carb.  but the small nipple aiming down toward the ground.  What hose goes there??


On the opposite side of the carb is another small nipple aimed at a 45 degree angle. what hose goes there??

Thank you for any suggestions of what choke cable I should use & where to buy it. and what hose goes on the two mystery nipples & what they are for.


Thank you!!




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Thanks to the help of TRs and Mike Anhalt, I was able to move forward with my ignition. I had hesitation on which wire I needed to install on the coil.  Thoes two folks gave me the info that I needed.


So I was trying to install a Varitronic Ignition.  But the translated Italian instructions were a bit to vague for me.  The only question I had was what wire went to the number 1 electrical connector on the coil??  Either the WHITE/RED or the RED.  The answer is RED.  The WHITE/RED is for the battery.  

So now I have the OG wires, Pink/Voilet/Brown & the new wires Yellow all hooked up on terminal #3 on the voltage reg.  Blue is going to ground, as well as terminal #2.  Red is now going to terminal #1 on the coil.  All I need to do is ensure that the ground is good and ground the motor to the frame too.



Thats if for tonight.

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