MOPED ARMY

With any moped that has been sitting for years, don't trust the tires and tubes not to be dry rotted. Plan on replacing rusty chain, cables, petcock, fuel line, and add an inline filter. Check the light bulbs. This gets you moving down the road safely. Check the wiring harness for bare spots that can short, especially under the fender where the tire could rub. Grease the wheel bearings.

Plan on cleaning a rusty or gunk filled tank. Check that the exhaust isn't plugged. Plan on cleaning the carb, getting a new needle valve, add a new plug, change the clutch bath oil, non detergent 20 or 30 weight.

You are gonna need to check for airflow, spark, and fuel flow.

Engine has been sitting for years. So don't expect great bearings, seals, and piston rings, or condenser. Spark plug coil good?

The major component of a moped is the engine, and in that case it's probably a Minarelli V1. You might not find a Bianchi Eagle manual, but there's plenty of info on that motor.

All those pieces and parts might run you around $200. If you aren't comfortable rebuilding a motor, there's plenty of people here than can help. There's some specialty tools involved which make a single rebuild more expensive the first time you do it.

Try to find a mentor? (edited)

I hardly know my way around the engine, but I have been able to free a frozen piston on 3 bikes and get them running. It's a crap shoot, so procede carefully, which you seem to be doing.

Invest in an impact screw driver to free rusty screws. Deal with the tank and engine first and worry about trim and tires last. I have been able to use bicycle cables for brake and clutch cable replacements but they aren't as thick and the ends break easily if you have to keep loosenibg and retightening them . I would get a 4 pack of cables at Wal-Mart for $10, throw away the shortest cable as it won't fit anything and make sure I cut the correct end off so the other fits in the hand control.

Definetly get the clutch lever working first if you free up the piston because it's tuff to engage the clutch, pedal the bike, have your hand on the throttle, and start it by yourself. If the throttle cable is bad, probably best to buy a new one as I have never been able to cheat on that one.

Don't get discouraged. Soak stuff in penetrating oil and don't force things to the point that they break.

Definite sign that motor is "frozen". Could be rings rusted against cylinder wall, bearings, or more. If you remove the head, you might be able to find movement in the crank and bearings if the cylinder can move up and down a little regardless of the piston being frozen. The amount of movement will be determined by where in the stroke the piston froze.

Get a block of wood that fits in the cylinder that you can tap with a hammer. You don't want to tap the top of the piston with anything metal that can crack it. Sometimes the break loose easily, sometimes you screw up the whole works, so go slow and careful. Plan on new rings at the least.

I had 2 V1 pistons tap loose easily enough that I was able to get them running, one just in the basement, the other I was even able to take it for a couple rides. If the rings aren't terrible, then you could they and clean up the cylinder a little and reassemble the motor to tinker with.

No, they normally have a curve to them.

Dang, that's got some "patina" to it! (edited)

You are doing every thing right.

I'm surprised experts aren't chiming in. Once you get that piston loose, I won't be much more help. I don't know my way around spark, points, clutch or flywheel. I tap the piston loose, put the engine back together, and see if it runs. It's worked for me 3 out of 4 times, so I've been lucky. The 4th time, the piston was so frozen that I pounded on it so hard I broke the bottom of it and put a gouge in the top of the case. (edited)

I've done a few different two strokes with points and such - timed them up and completely rebuilt a few. 70s Rotax for Skidoo sleds; twins. Did points/condensers and times a single Kohler in an old tractor I have; far from an expert, but not my first old motor.

Never had a stuck piston before so, always something new. Thinking I'm going to tie a weight off the pedal and tie off the clutch just to keep some pressure on it while it sits.

I did manage to get the side cover off, and then started on the fan. All the Phillips heads on the bolts that hold the fan there were rusted out, so - I tried to easy out them, 2 out of 4 on the fan came out - gave up on the others for now. The bolts that hold the cover just had the heads break off so, the other end is just rusted in - not sure if they'll tap out the other end of the housing, or what the fix will be there, but - whatever it is it will be new hardware.

Crank will rotate if I lift the cylinder up and down by hand.

Thanks for posting, keeps me interested and it is a reminder whatever the outcome, there is a light at the end of the tunnel. Today I was wondering if I just really like taking things apart … lol (edited)

managed to get the housing and fan off. electrical looked decent, at least there wasn't a mouse nest in there. Sprayed some oil into the crank, and up into the cylinder and hung a weight of the pedal with the clutch tied off. There it will sit for a while.

maybe tomorrow I'll put a pen in the plug hole to see if it moves when I put a wrench on the flywheel nut. I thought I was going to just let this sit for a few weeks, but can't help myself … lol

Take the carburetor and intake off. Then you can put some oil down in there from that side. If there is no gasoline around you could heat that cylinder up with a propane plumbers torch. I did this on a puch worked great.

Love that moto ski. I forgot what model but same as a skidoo elan

motor still stuck. changed orientation and put bike upright so I could try to take the headset apart and grease/service, and now just filling the intake with Marvel, seems to sink into the motor after a little while so - it has to be going somewhere.

motor still stuck. started trying to heat it up a couple times with a propane torch. not quite sure how hot to get it, so - just getting it all pretty hot and then letting it cool off. still don't think there is any movement of the piston when I rock the flywheel by the nut .. putting like 25 foot pounds on it, so - pretty stuck. just letting it sit with MMO in the cylinder and exhaust intake … figure I'll leave it like that and just heat it up once a day and try it a little each day.

after a while, I'll probably want to just knock the piston out - and either bore or get a new piston, would like to save the cylinder and use it if possible, but - who knows, maybe it will free up still at some point.

the bottom end is free and seems good. no vertical play in the rod or anything out of the ordinary. when I had the head off, the cylinder would go up and down and I could rotate and check out the bottom end a little bit, and from what I can tell, seems good.

I have tried some knocking on the piston with some wood and a hammer, and no movement at all. Unsure if the piston is just stuck from sitting or if it was seized up before it was put away. I don't see anything that looks bad about the cylinder or piston, although some light vertical scuffing does show on the cylinder wall, from where I can see the piston through the exhaust port, seems good.

In an effort to not break anything, I'm just sitting it with MMO in the cylinder and exhaust port, and then heating it up good a couple times a day, and working the crank from the flywheel nut to 20ish foot pounds. I figure I'll do this for a few to several weeks, and try to use time, heat, and soaking to free it up.

If it was seized will it eventually come free or will I have to pound it out with force? would like to avoid damage to rod and crank if possible.

Again, one of mine was so bad I pounded the snot out of it, the piston bottomed out, I broke metal off the piston, and put a bad gouge in the top of the case. I would think that if you have soaked, heat, and tapped on the thing for over a month, something would have to move by now.

I would get prepared to purchase a new piston, rings, and cylinder by now. If you need all that, you might as well at least wait for a sale from Treats and get a Polini kit or the like. Just the top end parts can't be that much more expensive than trying to find NOS stock pieces.

That thing should have broken loose by now.

well, got a chance to look at this again and make some progress, well - sort of, I think.

spent a little time whacking the top of the piston with a wood dowel and hammer. it seemed to me that the piston did move down, maybe half the width of a piston ring - viewing through the exhaust port - the bottom ring is right at the top of the port, so - could kind of gauge that more of it was visible and had moved down.

so, I put the head back on to rock the flywheel, and it sort of pops back to where it was, in one sudden movement as soon as I started to rock the flywheel with a socket on the flywheel nut. continued rocking of the flywheel did not appear to create any movement, rocked it for a few more minutes, put oil back in the cylinder and walked away.

so, is it just stuck? or is it likely a ring is busted and stuck in either the transfer or intake port? I don't know, it was just odd how it sprang back like that, but good news is it definitely moved, so - if it is just stuck, any oxidation, dried up old oil, or bond between the rings and cylinder should now be broken, so the penetrating oil should be able to work in there better now that the piston did actually move some.