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Discussion Starter #1
I've started to tear down my Bonnie so I can get cracking on my top end rebuild.

Things were going well, head came off easily, but now I'm stuck. I can't get the cylinder off. I turned the engine so both pistons are TDC, just like my manual says. All the nuts are off of the studs that hold it on, but the cylinder still won't budge.

I don't want to damage things getting it apart. Anyone have any suggestions?
 

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very gently,very gently,wack it all around with a rubber mallet.there must be rust in the barrel holes where the studs go through.put a bit of penetrating oil around them.warm the thing with a blowlamp.it will come off but be patient.if someone is pulling at the barrels while you tap it,it will help.cheers.....mine never gets stuck lol
 

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This isnt going to sound nice, but it worked for me.... once all the barrel base nuts are removed it is only the gasket that is holding the barrels on. Squirt a load of Plus Gas penetrating oil all over round the base to try and 'soften' the gasket. Find a length of angle iron / square tube and drill a couple of holes so that the piece can be bolted to the centre studs on the top of the barrel, with a useful length projecting backwards over the gearbox. Place a small scissor jack on top of the gearbox, wind it up VERY gently so that it lifts the angle iron piece and thus the barrels from the crankcase. You only need to lift it a little to break the grip of the gasket. Once that rear is lifted, turn it around and lift the front of the barrels a similar amount. Do not try to jack the barrels up any more than is necessary to break the grip of the gasket otherwise you may damage the studs at the base of the barrel.
 

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Ok, get your pistons to bottom dead center. Get a couple of wedge shaped pieces of wood. Pound the wedges down between the cylinder wall and piston. Give the kickstarter a good healthy whallop. The barrels will pop right off!
WAIT! STOP! I just realised I was reading my Harley service manual ! :lgh:
 

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Close, close, Nortonguy........put the pistons down to bottom dead center.......take a couple of shop towels and put them in ONE of the cylinders. Put the head back on without the pushrods or tubes and snug the nuts/bolts. Give the kickstarter a little boot and see what happens. Repeat as necessary. A little tapping with the soft hammer should help, too.
 

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Discussion Starter #7
Thanks for the tips...

1 large rubber mallet + 1 frustrated mechanic = cylinders off!

Just kidding, I was able to tap it a few times and it came loose. Couldn't find my rubber mallet so I had to buy a new one, but I guess that's what I get for not organizing my garage after our move!

Lightly honed the cylinders, actually looked really good when I got it apart. Lots of carbon built up in the combustion chamber, but cylinder walls looked good. No lip at all at the top of the cylinder wall where travel stopped.

I'm going to try just new rings without boring it out and getting new pistons. Keeping my fingers crossed.

Valves were horrible. Must have been sitting with them open or something (storage last 15 years). No way they could make a decent seal. Heavy cleaning, some lapping compound, and things look much better. Actually ended up with decent seating surfaces. Felt like I was trying to start a fire with my suction cup on the end of the stick, but things looked good when I got it back together.

Once I get some new gaskets, I can put it back together and see if my efforts paid off. From the looks of the valve seats when I took it apart, there should be a noticeable difference!
 
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