garelli ssxl milled head

i own a stock 77 garelli ssxl

14 12 dellorto 56 jet

problem: starts easy first time, dies when i come to a stop, loss of power

i milled the head 1 mm or more

that increased compression and gave me more power (very happy)

can feel more resistance when starting

i cut off 6 inches of extra exhaust manifold that stuck in to exhaust (no change)

removed intake plastic cover


plug chopped (more power)

PROBLEM STARTED and slowly got worse

i recently cleaned the 1 speed transmission

it was loaded with crap smeared on the bell

i even sanded down the rubber clutch 1 mm b/c i thought this was problem with idle

clutch grabs well when starting but the added resistance after i milled the head is gone

problem got worse

i noticed right after running it there were bubbles in the tranny oil

is this normal?

found air leak between head and cylinder

fixed that. no improvement

sounds like ring slap

also recently found strange build up on head. it wasnt there before. why is it glossy?

i also cleaned the carb about a thousand times and put an in line filter. idle hole is clean blasted out both directions with carb cleaner, and poked with a wire

im considering is my base gasket bad?

piston rings? (edited)


Re: garelli ssxl milled head

what happens when you "UPJET, DUMMY"?

piston's getting hot, how long ago did you decarb the crown and head?

maybe try testing the compression.

rings carboned up and stuck, sides of the piston black?

loss of compression after running too rich garelli

this is my first moped. I bought it a few months ago and don't know a lot.

how do I get my engine to run cooler? I read in the basics that a biger jet will keep it cooler.

I don't have a compression gauge right now but before this problem started there was much more resistance when peddle starting. clutch is good.

it started losing compression when I was running too rich for a few was for stroking like mad. Could that be the cause of all the carbon build up and possible stuck piston rings?

do I need to replace piston rings? if I do that do I need to hone the cylinder and get a new piston?

I haven't taken the piston out yet to see if the walls of it are black or if the rings are stock (edited)

Re: garelli ssxl milled head

50:1 oil pre mix, over mixing creates a lot of carbon build up, also makes it seem like its running lean and hot because, well it is. More oil in the fuel means less gas, means leaner burning. Also try running 0-20 synthetic oil in the case for your clutch.

Re: garelli ssxl milled head

the glossy black may be from overheating when you had the airleak:

"found air leak between head and cylinder fixed that. no improvement."

sorry i missed you already upjetted.

you may still have airleaks, eliminate those #1

to easily check the rings without disassembly, drop the exhaust, and move the crank while looking in the exhaust port.

rocking the flywheel a little, you should see the rings move.

Re: garelli ssxl milled head

Thanks for the advice. I'll work on it soon and get back to you.

Re: garelli ssxl milled head

I took the engine apart and I found a chunk missing from one of my piston rings.

How do I fix this?

Is the piece missing between the two rings for oil?

Do I need to hone the cylinder?

Do I need a new piston?

Should I be worried about this piece of metal being somewhere between the engine and trans?

Do I need to replace the bearing that connects the piston to the crank?

Also how does that bearing stay oiled?

I hope I only have to replace the rings.

The cylinder looks in much better shape than the piston.

I couldn't feel any scratched with my finger, but I could a little bit with my nail.

I can't wait to ride.


Re: garelli ssxl milled head

>Is the piece missing between the two rings for oil?

no, it's for compression, = power.

>Do I need to hone the cylinder?

yes and no, replacing it is the safest bet, but it's cast iron, not nikasil.

>Do I need a new piston?

yes, the pin that keeps the rings from moving is gone it looks like.

>Should I be worried about this piece of metal being somewhere between the engine and trans?

naaaa, but unless you split the case, you'll not know, but it prob went out the exhaust.

>Do I need to replace the bearing that connects the piston to the crank?

a new top end should come with that needle bearing, but does the underside of the piston near that bearing have black carbon, did the wrist pin that bearing rides on get hot and discolor?

>Also how does that bearing stay oiled?

only the engineers that designed that motor know for sure, oil vapor is sufficient, good quality oil is cheap insurance.

>how do i fix this?

treats has a lot of options for garelli noi motors

>found air leak between head and cylinder

you need to check the head for flatness, lightly sanding on a glass flat surface with fine (like 600 grit) sandpaper will show you if the head is warped, mine was.

then properly torquing the head down (then heat cycling and retorquing) will prevent future leaks.

this is only a minor setback, don't be put off.

Re: garelli ssxl milled head

Thanks for all the help and knowledge.

I attached pictures of the under side of the piston, the wrist pin and the crank

I can't afford new parts right now so I want to re-build with as much original

This engine did run if I started it at mid speed and just the right throttle, but was having clutch problems

Yes the under side of the piston is black (see picture)

The wrist pin looks a little discoloured bun is perfectly smooth

I was able to get out the pin that holds the piston ring in place by tapping it on a table. Can I replace that pin and use the old piston

Do I heat and torque the head by riding then torque again and again?

The old head gasket is still in the head and keeps squashing a little.

I was pretty discouraged when I couldn't figure out what was wrong with this thing, now I just want it running again, so I can ride.


Re: garelli ssxl milled head

i won't tell you what path to take with repairs, but you get out what you put in.

that piston is trash to me, replacing that pin has been done, i wouldn't trust a repair like that.

i'm not sure of different garelli piston sizing to buy one off of the buy / sell forums, but that could be as cheap as new rings alone.

judgement call on the cylinder being ok, leaning towards go with the gamble if money is really that tight, if it's barely catching a fingernail, light sanding (a proper hone is far superior, but $) may give you more life out of it.

new rings on a worn cylinder wall won't "break in" or seal properly or as fast as on a honed wall.

but the good news is, it's not a high compression / high performance motor to begin with.

rest of the pictures looked decent, except for the missing chunk of piston ring, did you check the exhaust, bang on it to see if it's caught in the tarry goo inside?

no damage to the head from that piece thrown around atop the piston?

i torque the head, ride a little ways part throttle, tuning run, then let it cool to retorque.

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