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Harley Ironhead Pistons and Cylinders

Life's a bitch...   Thank God there's Harleys...

It took a while, but we've got our cylinders bored, and we've got a new set of oversize pistons to match. Our overhauled 1973 Harley Davidson Ironhead Sportster engine is starting to take shape!

Cylinder boring did not go without problems. Actually, one of the cylinders had to be replaced by a "new" one.

Click HERE to read the story.



Ironhead Cylinders and Pistons - Ready to Install

Here's an overview of the refurbished cylinders, new oversize Ironhead pistons, new piston rings, and new cylinder gaskets, ready for mounting into our Ironhead engine.

Photo of new oversize pistons and bored cylinders for our 1973 Ironhead engine - by Harley Oldschool Bobber. The new oversize pistons are by Motorcycle Storehouse and - as far as we are aware - are the largest size available. Piston rings by Hastings.



Ironhead Engine Taking Shape

Photo of new oversize pistons mounted on our 1973 Ironhead engine - by Harley Oldschool Bobber. Here's the new oversize Sportster pistons fixed to the connecting rods.


Photo of new oversize pistons and bored front cylinder mounted on our 1973 Ironhead engine - by Harley Oldschool Bobber. Next step: Front cylinder in place!


Photo of new oversize pistons mounted on our 1973 Ironhead engine - by Harley Oldschool Bobber. Both cylinders have been bored to 82.5 mm diameter. The stock stroke of an Ironhead engine is 3.8125 inches or 96.8 mm. So, after boring this is now a 1035 cc engine!


Just for reference:

BEFORE Cleaning and Rebuilding (May 2008)

Photo of 1973 Ironhead engine before cleaning and rebuilding - by Harley Oldschool Bobber. Just for reference, this is how our 1973 Harley Sportster Ironhead engine and cylinders looked like in May 2008 before cleaning and rebuilding. CLICK HERE for more details on this heap of dust and grime.

And now:

AFTER Cleaning and Rebuilding (April 2009)

Photo of 1973 Harley Davidson Ironhead Sportster motor after cleaning and rebuilding - by Harley Oldschool Bobber. This is how she looks like at this stage of overhauling. Can you imagine that even if this Harley Ironhead engine has not run yet, she has already given us a lot of satisfaction?



April 2009