The tear down (part 2)

I figured it would be best to do the engine rebuild before the chassis rebuild (as there wouldn’t be so many parts floating around).  Plus – engines are a bit more fun in my mind.

Given the age of the bike (and because it was running a bit wonky when I purchased it…the left cylinder wouldn’t fire unless I had my hand over the carb), I decided to completely tear the engine down.  I was concerned that those old two-stroke crank seals were the likely culprit.

After receiving the crank seals and lower rod bearings, I brought the crankshaft and cylinders up to Bill Bune enterprises in Anoka MN to be rebuilt (the cylinders were just re-honed, as I installed new rings on the pistons…at 3500 miles, there wouldn’t be a need to bore the cylinders).

Here are a number of pictures of the whole process.  This engine is fairly simple – and thus I had no “gotcha” moments (other than a stuck stator rotor):

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My makeshift bench to hold the engine parts (used the cardboard trick below to know how the bolts go back into the right place):


The stuck rotor…it finally came off after some WD-40 soaked the shaft for a few hours:

WP_20150321_008The case in half – time to bring the crank to the shop:

WP_20150322_008Engine block cleaned and the halves back together:

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And…the pistons reinstalled (with the new rings), cylinders back on, and clutch cover back on (after polishing)…the air ram system still needs to be cleaned up:WP_20150517_004Now, on to the chassis!