2 or 4 new pistons?

[RebelSkyRot]

I have to buy at least one new piston, probably two, but debating on four. Are pistons something you should replace all of if you're getting new ones or is it okay to just replace a couple?

 

[VonYinzer]

Need more info... Why are you replacing any pistons? Generally, you can juat replace whatever piston is unuseable.

 

[RebelSkyRot]

A small hunk of piston 3 in my '74 cb750 broke off right below the pin and gouged my cylinder. I have a new cylinder and rings, so all that's left is to buy a new piston(s). Originally I was just going to buy one to replace the damaged piston but the casting on piston 2 looks kinda faulty at the same spot where piston 3 broke off. I don't know much about piston castings and all I'm just comparing it to my 2 other good pistons and it definitely looks different. SO, I was debating whether or not to play it safe and just spend an extra $80 to get 4 new pistons instead of 2.

 

[dnhnky]

My thoughts are since you have it apart, put it back together correct the first time. If you have to question something as important as a piston, replace it/them.

On the other side:

If you have more time than money, do what you have to in order to get riding.

I tend to be in the later category and find it relaxing to turn some wrenches. My .02.

 

[Sonreir]

The shop manual will have the specs for a "good" piston. Measure it and find out. Don't just guess.

 

[VonYinzer]

If you don't KNOW its right, its wrong. If youncan swing all four buy all four.

 

[teddpage]

Not for nothing, but if it were me, the extra 80 bux to get all 4 pistons would be a no brainer. Do it right the first time, and avoid any headaches farther down the pike. You will thank yourself.

 

[RebelSkyRot]

I just decided to buy all four and either throw the others up on ebay, cl, etc. or maybe turn em into a decoration or something artsy