V1 Marinelli Trouble Shooting

So I have a 1977 Cimatti City Bike with the Marinelli V1 motor.

The problem as of yesterday (day of purchase) is that when I'm cruising at about 25-30 mph (the best the moped can do for now) for about 5-10 minutes at 3/4 throttle.... it will bog down and shut off.

This is driving me nuts today.. any trouble shooting ideas would be great.

My guess is the plug is too hot or there is a problem somewhere in the throttle mechanism (carb).. not the cable or handle.

This my first moped.. and unfortunatley my friend left all the books and manulas down in San Diego... that cocksucker.



Re: V1 Marinelli Trouble Shooting

If we all get one guess...

Mine is the condenser is bad.

Re: V1 Marinelli Trouble Shooting

it could be a soft seize if the carb is dirty and not flowing enough fuel. remove the carb, take it all apart, clean it out, put it back together. also pull the head and take a look in there to see if theres alot of scuffing/scratching or if its smooth.

congrats on getting a good solid moped with a good solid motor. they really are just about bullet proof if theyre not the fastest. some tomos rear shocks will fit on it, but are a little long so your center stand wont let the back wheel spin. however they REALLY improve the ride over bumps ALOT.

Re: V1 Marinelli Trouble Shooting

could be a rusty gas tank mixed with dirty carb or an air leak. The bogging shows signs of dirty carb or air leak while the dying engine seems like crap is getting in your carb- I.E. dirty/ rusty gas tank-

1st. Clean the carb very well --then reinstall and while it is idling spray carb cleaner at various points around the carb and intake- if it kills the engine you have an air leak. If so, use RTV gasket red sealer from Napa or auto zone and seal up where it leaks.

Also, for the tank I would install in inline fuel filter from auto zone- costs 2.50. it is easy as pie to install and will prevent most light rust/dirt from your tank from clogging your main jet in the carb.

If it still bogs you most likely are running a too large main jet (brass screw in carb) and you need to down jet. its a dellort 14.12 on a V1 right? good news is 1977mopeds has all ranges of dellorto jets for you. Though my bet is on 1 and 2.

Good luck- i dont think it is the condenser personally. nor a soft sieze. 1 and 2 are the most common issues.

Re: V1 Marinelli Trouble Shooting

Never have delt with a Minarelli, but here are the following things to do with any used moped:

1. Clean the carb. Take it apart and wash/swirl it in gas. Then dry everything off and put back together.

2. Remove all carbon. Most peds get carbon on the head and piston. If black/dark brown, use steel wool and remove it until you can see the original color.

3. Change the Plug. Use an Autolite 425, NGK B6HS, ND W20FS-U, Bosch W9EO or Champion L86C. Put the gap at I believe .26 - .28mm

4. Change the fuel line and petcock. Use 3/16" Nitrile or Tygon fuel line, it will last the longest. Also use a fuel filter or two. Also, replace the petcock, sometimes the filter on it corrodes and lets rust build up. Save time and buy one.

Try tightening the nuts on the engine studs. After that, if it still doesn't run properly, adjust the carburetor and check the electrical like Mark said.

Good Luck

Re: V1 Marinelli Trouble Shooting

Matt Scout The Scouting Dcon /

Threw some Sachs Eagle II shocks on my Snark. Had to drill the bushings out to fit the bolts. With my weight I was bottoming the stock ones out! Rides much nicer now.

Re: V1 Marinelli Trouble Shooting

Well if it just dies out after warming up it very well could be the condenser, dont rule that out.

Re: V1 Marinelli Trouble Shooting

not the condenser... she can idle forever.

Re: V1 Marinelli Trouble Shooting

the tank is in MINT inside and out... I have a spare carb that came with the bike... I'll double check the main jet size... and go from there.. put a quick three miles on her this morning with no problems!

The fuel line and petcock look to be in almost new condition.


Re: V1 Marinelli Trouble Shooting

Quote: "Remove all carbon. Most peds get carbon on the head and piston. If black/dark brown, use steel wool and remove it until you can see the original color."

If the carb clean up / possible replacement does not solve the issue... this step will be in order.

What might the torque spec be for putting the head back on ?

Re: V1 Marinelli Trouble Shooting

good to know stuff!

Re: V1 Marinelli Trouble Shooting

did you test for an air leak yet?

Re: V1 Marinelli Trouble Shooting

I would have thought fuel starvation. Is there a kink in the fuel line?

Remove the fuel line from the carb and let it run into a clean container for a number of minutes to see if it slows down.

Have you cleaned the screen on the carb under the banjo fitting?

Re: V1 Marinelli Trouble Shooting

Next time it does it pull the fuel tank cap off. The vent hole might be plugged.

Re: V1 Marinelli Trouble Shooting

after you do everything that silverfox says then add a fuel filter- then seal intake and floatbowl area with rtv sealer.

Re: V1 Marinelli Trouble Shooting

Here is the low down...

I pulled the fuel line, checked the petcock vavle for debris... Good

Inline Fuel Filter is clean and new... Good

Checked behind the banjo fitting and that screen was clear of debirs... Good

Pulled cover and retaining ring off of air filter... Good Filter

Took her for a spin after making final adjustments to the throttle.. and she rode like a rock star!!!

Only thing left to to is get a new throttle cable, possibly a spark plug change, and check the throttle/grip assembly.

I suspect the throttle cable/grip for the poor idle.. it used to idle and now it just dies... but I can tell that the RPMs are not the same as before after making the throttle adjustments. plus the damn grip mechanism is janky and weird.

thanks for the help!!


Re: V1 Marinelli Trouble Shooting

Bout time for a spell check... hahaha Minarelli... where the f*ck has my brain been this week?

Re: V1 Marinelli Trouble Shooting

wd40 the throttle grip insides- that might help.

Re: V1 Marinelli Trouble Shooting

Isabelle Castillo /

Can u pleeease show me what the inline air filter looks like? I'm trying to replace mine in my 76 cimatti but don't know what it resembles. If I have to maybe I can make my own.


Re: V1 Marinelli Trouble Shooting

The air filter is attached to the carb air intake .

An inline fuel filter may be in the fuel hose from the tank to the carb .

If there is none , it would be a good idea to add one . It should be a paper filter , good to at least 60 micron .

Re: V1 Marinelli Trouble Shooting

What gas to oil ratio are you mixing? Should be at least 3.2 OZ. of quality 2-stroke oil to one gallon gas.

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