Hello

Here's pictures of my pinasco kit I was using with a longstroke, phb30, with a completely rebuilt engine new bearings, seals...

And here's what happens last week, and I only had 2300km since the rebuild with a fully runnin-in.

How can this happens, do you think it's a default in the pinasco kit ?

I´m shure that this is basicly a weak point on the pinasco kit. But to break it, it need a force or other trouble there.

How look the broken part? Is it with any "bubbles" inside the material?

Do you drop the cylinder?

Maybe a small crack already when you received the kit (during transport demaged) ?

You are from france, right? So you don´t have a 80cc block. At 80cc is the thickness of the cylinder wall even smaller...

High,

have you cut the cylinder and or the piston. Perhaps you deburred it badly and therefore the piece broke away. But more important is the question, where the missing piece is gone. Have you found it or is it somewhere in or arround your crankshaft.

so long......

Didn't Lucifer mention, that he made the expireince, that 177 cc Pinasco and longstroke always was an instable engine?

@bug

no, lucifer suggest Pinasco 177 with longstroke. He mention not to use a HP4 because of the weak piston rings.

But anyway, to get a demage like this, it is not even importend to have HP4 or not .

@250bein_ässe I don´t think that there is something cutted. This kit looks like a virgin

The broken part went through the piston and surely exit via the exhaust after hitting the head, but by miracle the nicasil is perfect, but the piston is damaged.

And some goes in the crankshaft.

beodeo : what do you mean by "drop the cylinder" ?

I'm from France, and it's a P125 engine. Broken parts have no bubbles

250beinaesse : I haven't cut the cylinder.

I've written SCK about it, but I still haven't got any response... but with friends, we are pretty sure it's a default...

do you drop the cylinder --> fall the cylinder down, on the ground?

No, really !

hi

i also use the pinasco 177 with a 60mm stroke and a 30mm mikuni, once i heard that the piston might touch the cylinder right where your damage happend because of the longer stroke, to work against this problem you kann cut off half a mm from the bottom of the piston. but this is all theoretical stuff, i also din't cut the ends of the piston and my kit works since almost 16000km and about 1000km with the longstroke and still the nicasil looks like new, so this musst be a damage.

the other theorie is taht a piece of your piston ring probably broke off and caused the damage in the cylinder???

don't give up in my opinion this is one of the best manufactured kits in the 177 class

good luck chris :grins:

The rings weren't broken, glued to the piston but not damaged.

I'd like to don't give up, but I'm not sure to get this cylinder exchanged with a guarantee from SCK.

But by the way it's my second Pinasco Kit and the first one never caused me any problem with a standard stroke.

you have to be carefull with the ignition don't set it too early, remember with the longstroke the piston gets more speed because of the longer way it has to travel, therefore it also causes more heat, start your ignition with 19 degrees and set your phb, if its working you can go up to 20 but i would rather not set it at 21 degrees like pinasco sugested

and dont use the hp 4 lucifer has high knowlege about this theme and i think he is absolutely right

can you post pics of the piston maybe it got too hot and a peace fell out of its middle and caused the damage

That's the only pics I got from the piston.

But nothuing seems to fall apart from it.

For the ignition i was running 19°, and since a week I was riding it at 21° as Lucifer told, and setting it with a timing degree disc because of the problem of marks with the HP4.

was the piston bolt clip in place on the side the cylinder is broken?

from taking a short look, i guessed that it went loose and took a short trip through the cylinder?

danke jungs

Bearbeitet 4. Juni 200323 Jr. von gravedigger

what about the top off the piston is there a hole or something brocken???

on the first pic i think theres a little pice missing right over the ring is that true????

the piston looks like it got too hot and run out of oil, maybe your phb was set up too slimm???

Bearbeitet 4. Juni 200323 Jr. von sprint chris

gravedigger just said the piston's edges look sharp and unbroken / "un-rounded"... maybe the piston hung with a sharp edge of a window and ripped out the part?

what gravedigger wants too say is that the edges are sometimes not manufacured very good sometimes there are little pieces of metall left after building the pison right on top off the rimm or inside the head of the cylinder

as nop says sometimes these little pieces break off and take the way trough the cylinder, i also think this might been happend, if such a piece gets stuck between piston and cylinder it make break the whole thing

wollte deine übersetzung nicht schänden nop du warst einfach schneller

@nop : yes the circlip was in place I removed it to remove the piston, that's all.

and the piston is as it comes frolm the box, I haven't rounded or sharpen anything.

@sprint chris : on top I got a mark because I use a tool to "stop the piston move" for undoing the flywheel, but it never has been a problem with other engine, and a friend of mine used this tool on all the client scooter with no problem.

Maybe your explanation/theory is good, but it would have happend only after 2000 km ? not before ?

I'm going to see the piston at the shop today, I'll take a closer look, thanks.

So what would you recommend me to do if i get or order a new kit ?

the best thing do do is, place the piston in the head and make sure that there is enough space, remember the longstroke forces the piston 1,5mm higher into the head of the cylinder, reound the eventual corners in the head, if you want you can also round the piston bottom a little bit, for testing use again 19 degrees, make sure your phb 's setup is 'fat' enough especially in the higer range don't use the hp 4 take the modified pk flyweel

i bought a new mikuni 30mm for my setup i think it works much better than the phb

take a close look for bubbles holes and sharp edges in your kitt

do you use a membrane???

which exhaust do you have???

best luck

chris

For the longstroke I got a piece in aluminium to raise the cylinder that goes between the cylinder and casing.

If I order a new kit I'll reound the corner.

And ok i'll set it back to 19.

I don't use a membrane, only the malossi manifold, with a PHBH 30 BS and actually a 118 main jet.

And I got a SIP pipe in stainless, but it's a big sheet it always broke on the welds near the part that bolt to the casing.. I'm very disapointed with it, a friend of mine got the same problem.

I was thinking of upgradind to a PWK Keihin 30 carb.

What jets are you using in your Mikuni ?

right now i'm jusing a 305 main jet that's combiend with a 80 powerjet (summa sumarum 385)

but the cylinder isn't really that originall anymore :grins:

i Don't know the kaihin carbonator

I'm sorry about your sip i never heard anything bad of it I'm using a pm evo but it's not the best choice

so long chris

Now let's here my stuff! I had the same Problem like you, a half year ago. It was an PX 80 engine which cylinder hole was widen, cause of using the 125er cylinder. But this machine didnt't widen enough.

On first tour, the cylinder got warm, seized his cylinder foot and *peng* it broke. Now I had cut out these stripes on both sides, it's not good, but ist works since 20000km

@ lor@n

how about spare parts for keihin carb´s in france? In germany its pretty lousy, except you can translate your needs into Art. numbers of KTM or others.

Do you have Koso carb´s in france? it´s a Keihin copy from Taiwan...

P.S. don´t compare your jettings to other (complete different) engines...

@der metzler echt das hat funktioniert wie hast du das gemacht einfach an den strömerfenstern entlang nach unten geschnitten oder wie ???

@ Sprint Chris Jenau, einfach stumpf nach unten. Hab den Zylinder umgedreht, das Nicasil entfernt und mit der Bügelsäge weg den Dreck. Funz! Einzig Problem ist halt, das der Zylinderfuss sehr lang ist und viuelleicht etwas instabiler wird. Aber Funktion haben die Dinger sonst nicht