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Discussion Starter · #1 ·
Hey guys i just finish putting my bike together and went to break it in. It started up just fine and was great while it was warming up (minus the getting it was running a little lean). After the motor started reaching operating temperature, the motor seized up on me. I had the cylinder and piston sent off for nickasealing and it was bored .80 over in the process. It's got a Wiseco 12-1 piston, Hot Cams Stage 3 cam, and K&N air filter with an open box. All fluids were replaced with the parts and a generous amount of assembly lube was used on all the new parts. I'm looking for any help on what could be the cause of my motor issues. Thanks a lot for any body that has any input on the issue.
 

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What seized? The cam? The piston? The crank?

When the cylinder was bored and plated, what was the piston to cylinder clearence set at?

Without more details, my first guess would be improper assembly. Some inexperienced mechanics use gasket sealants and inadvertently block oil passages.

Let us know what failed.
 

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Discussion Starter · #3 ·
Just tore the engine apart and found that the piston had seized inside the cylinder. There was deep scaring on the back of the cylinder wall but only light scaring towards the front. The cam was fine and still had some assembly lube on it. I didn't use any gasket sealants during assembly and there was plenty of clean oil laying in the head when I took the valve cover off. As far as piston to cylinder clearance that I don't know, but the piston did seem a little tight when installing it. I just assumed that it was set when I sent the cylinder and piston off for plating.
 

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Aside from the possibility of overheating during warm-up, the piston to cylinder clearance may not have been correct. The recommended clearance for the 4849M09600 Wiseco piston is .0030 inch. If you sent the piston (out of the box) with the cylinder, but did not specify the desired clearance, it's likely the plater set the clearance at the std. Honda recommended clearance of .0004-.0022 inch. Who did the cylinder work?

Unfortunately you are going to have to get another piston. Hopefully there was no cylinder damage or it will have to be redone also.
 

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Discussion Starter · #5 ·
Well good news, the cylinder was not harmed! There were some spots on the cylinder where the piston left some metal. The only bad thing is that there was light gaulding on the piston skirts. The piston clearance was set too tight, we honed the cylinder out to the right clearance which in turn cleaned the cylinder and got rid of the metal that was left on the cylinder walls. We also cleaned the cylinder skirts and remeasured them, they are not ovalized after cleaning them, I was going to see about reusing that piston with a new set of rings??
 

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Using the damaged piston is a gamble. It will work, but it will most likely be noisy and there is a greater chance it might break versus a new one. A new piston might break at the extreme stress and heat that a modified engine may subject it to, but the chances are less than using a damaged one.

Congratulations on saving the cylinder and good luck.
 

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Discussion Starter · #7 ·
Well there was a lot of piston slap within the cylinder so I am going to have to do something different. Can you bore a nickaseal cylinder? I don't want to go much bigger than what I already have and I am at 80 over right now if I can even go bigger.
 

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You can't go any bigger without a "big bore cylinder". A big bore will take it out to 99mm, but your cylinder can be repaired. Send it to U.S. Chrome in Wisconsin. They can replate it and hone it to proper size, but you will need a new piston.

By the way, who did you have bore and plate it when you took it out to 96mm?
 
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