Thank You! My roommate's Honda Hobbit has a decomp valve, but I have never seen one on a Puch bike here in the states. I hear you on the end bearing part, the one on my first Puch took a ton of abuse two years ago when I had no idea what I was doing, 2,000 miles later the whole top end is in awesome shape still.
I wish that I had seen this video sooner, I had advanced the timing on my 1980 Sach Sundancer too far. I ran rode the bike and in the morning found that it was seized, I simply used the flywheel bolt to break it loose, it broke loose easily and seems to be alright. next time I will at least use penetrating oil sprayed into the sparkplug hole and obtain a temperature gauge. Thanks guy's!
Thanks You! RU-vid won't let me post links in comments, but you can google: treatland 1977 mopeds moped junkyard and... The MopedArmy Buy/Sell Forum, which will be your best bet for old/original moped specific parts like sidecovers. Treatland has a great selection for "new"parts like gaskets or pullers. The moped junkyard is good too but their prices can be higher than treats or 77mopeds.
Nice tutorial :-) I did notice the decompression valve and cable had been deleted from the head, another difference between the uk and us models i suppose. The phospher bronse little end bearing can put up with a hell of a lot of pounding, unlike modern types, yes im a stick in the mud :-)
Sorry to ask a question so many years later, but I believe my moped engine seized after not having the right fuel oil mixture. It was ignited twice before stalling and completely dying, but is it possible to unseize or repair the issue by myself?
Odd isnt it how we all get slightly different versions of the same thing. On my first puch maxi 'N' type with solid back frame i had to change the little end bearing, well we had a special only puch shop that supplied the part. But one thing they dont tell you is its not a drop in part!!, you have to get an adjustable blade reamer and slowly take material out so the (gudgen pin/piston pin/wrist pin), just fitted snug in the bearing in the con rod. What a pain in the bum lol
Nice tutorial! And the other ones helped me a lot. Just have a question. I'm repairing my father's 1974 Puch Maxi S and i can't turn the flywheel a full turn. The piston moves but just a bit. Any ideia what is the problem? Once again, thanks for all the tutorials. Cheers
This is an extreamely helpful video. I have a '78 Batavus Laura M56 engine that I'm trying to get unstuck. Unfortunately, after I pulled the head I saw surfice rust throughout the top of the bore. I'm hoping I can clean that up. Got a question though. Where do you get your parts from? I need things like head gaskets, engine side covers (clutch & flywheel), and I may need the electrics under the flywheel. Plus some tools to get the flywheel,clutch and all that off. Thanks.
grate work man! i have 2 old Derbi variant moped. the 1e is the variant start. that my boss give to me. it was his 1e moped when he was 15 year. so i restored new paint every thing but i did no do a motor re build (just dont have time for it) it won't start. the sealing rubbers on the crank case are f+ckt ... anyway i find a 2e Derbi Variant for 50 euro.... and its motor is seized.. i look every where but no good info... until now! thank a lot!
If memory serves me correct, this one was fine for riding after, but it's a toss up. If you want to guarantee something will last it's a good idea to rebuild it after it's been hard seized
+jazzbuckeye You mileage will vary, as it's a case by case basis. If the piston was only stuck a little bit, you could probably get by with new rings and a hone. For that to be the case though you'll have to check a few things, for example does the piston still pass the "piston drop test" - that is where you "drop" the piston through the cylinder with no rings in it to check if it's deformed. You'd have to make sure the new rings move and seat properly. Even then, you could probably sand the piston a little strategically and save it. A lot of the time the piston could likely be salvaged, it just comes down to the extent of the damage, the time to repair, the skill.
Hi, im having a big problem here. I watched this video several times but i cant seem to make any progress. My scooter (yamaha neos) 50cc moped has a seized piston. I took the cylinder head of and tried turning the crankshaft. The cilinder does move away from the block but the piston is completely stuck in there. I tried putting some wood between the cylinder and engine block itself and hitting on the piston with a socket and a hammer. The thing didn't move at all. Any tips to solving this issue?
@@whowho7969 Yes, I watched a different video. I took a piece of steel (+-2cm thick). Drilled three holes. Tapped the center hole for an m10/12 bolt. cant remembrer. Take the cylinder head off. Bolt it the steel bar on like a half x (cross) over the cylinder. So diagonal on top of the exposed piston and cylinder bore. Snug the steel bar down with the nuts. Now get your m10 bolt (a long one) and thread it in with a ratchet. Piston should move down. Took a lot of turning and force but this worked excellent for me. I still have the old piston and cylinder as a memory. Total carnage! 2-3mm deep grooves
I have a puch moped that has been sitting a while idk how old it is but it's pretty old it's not seized the piston moves but idk if its worth rebuilding it has wiring that is scary to look at but I want to fix it how hard is it to rebuild these
