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[Felix]

After waiting a month for machining on my barrel and head, I find the wrist pin won't enter the Robbins piston even after heating it to 2nd degree burn level. Back to the shop, and $50 later it fits like butter. I decide to start tomorrow, but my wife is off to a meeting this evening so it's out to the garage. While futzing about, the piston with rings drops slowly into the cases. as I rotate it back up while guiding the piston. I hear a click and I get that sick feeling. Yes, the oil ring snapped and I fish out two of the pieces but not the third. I get out my magnetic wand and fish out a sliver of cast iron that completes the ring. Time to celebrate!
Is it possible to load the piston into the bore, then lower the skirt and insert the pin? I want to minimize mistakes when the new rings arrive from H-land.

[Felix]

Oh, mea culpa.
500 2000 Bullet.

[Leon Novello]

Is it possible to hire or borrow a ring compressor, makes it so much easier.

[Alan R]

Hi Guys-----with all due respect Leon but you really don't need a ring compressor for the iron barrel 500 single......Have a look at the bottom of the bore where you'll find a very generous taper already machined in.......Place a piece of wood across the crankcase mouth and rest the piston skirt down onto this......Now here is the important bit}----- Even with a new piston & rings you MUST GAP THE RINGS FIRST.....This will ensure that there is enough room for the rings to close up when inside the bore without butting up and making the ring oversize and thus snapping...............Give the bore and rings a generous oiling then after applying the base gasket you gently lower the barrel down onto the top of the piston....Use a combination of slightly wriggling the barrel in a circular motion such that the aforementioned taper is encouraged to "capture and compress" the top compression rings...at the same time allowing the barrel to be lowered down until it touches that piece of wood........By now all rings will be within the barrel and unbroken...Withdraw the wood and fit the barrel down into the case mouth.....there you go---job done !!...........That's how I've done mine in the past and never a broken ring--honestly..

[Felix]

Thanks guys.
I probably would have the bike together now if I had blocked the piston in place. I made a compressor tool just in case.
You're lucky to have our host nearby.