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Engine Mechanical TopicsDiscussion for motor builds, cams, head work, stripped bolts and other engine related issues. The good and the bad. If it goes round and around or up and down, post it here.
Fist of all, I am new to vtwins. Just joined this forum after stalking around a few days. I picked up a 94 1200 sportster from a family member whose deceased friend left it to him. I don't know much history on the bike other than it was "surprisingly quick for a sportster". The pictures show what state I got her in.fron what I can tell it may have dropped a valve(one missing) and/or had some serious preignition as the damage is in both cylinders. Bike was pulled apart when I got it already.
I am planning to rebuild her and get it back on the road. My questions are:
1- anyone seen this damage other than from something knocking around inside the cylinder?
2-what else should I be looking at before I start to put it together?
3-what compression can I get away with on this junk ethanol fuel we have today? New to me. 94 Sportster 1200 Broken rings and chunks of the crown gone. Missing a valve. Could be what caused all the damage?
I would guess the valve was removed as it probably bent when whatever was in the combustion chamber was bouncing around. Looks like the dish was cleaned up, but there are still some marks on the periphery where the piece (nut, maybe?) was bouncing around. Looks like it did a number on the land of the top ring. It might be worthwhile to see if the combustion chamber of that head is anywhere close to the other since some material was likely removed to get the "dings" out.
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