Hello every one, need some info on installing a new piston. I have had my piston out 3 times and things keep breaking. (Every time, my fault) I ordered a new piston with rings and a new cylinder. I was just reading about when you take a piston out you should mark the front, I did not do that. How do I tell what the front of the new piston is? Or does it really matter? Thank you.
Piston install help
- Thread starter lowridr
- Start date
Looking at the cylinder, from the rear (intake port facing you). You should see both piston ring pins. Top pin to your left and bottom pin to the right.
I find this the easiest way to insert a piston in these HT's. Others will tell you differently.
With the cylinder off, lay cylinder head down on a work area. Line up the rings on the piston grove with the pins. Insert the piston from the bottom of the cylinder. Compress top ring and slide in, then the bottom ring the same way. The cut outs on the cylinder lets you hold the rings with your thumb and forefinger. Lightly tap in. The bottom of the cylinder is beveled and guides the piston in. Take cylinder and piston and insert the rod, make sure the wrist pin clip is installed.
I find this the easiest way to insert a piston in these HT's. Others will tell you differently.
With the cylinder off, lay cylinder head down on a work area. Line up the rings on the piston grove with the pins. Insert the piston from the bottom of the cylinder. Compress top ring and slide in, then the bottom ring the same way. The cut outs on the cylinder lets you hold the rings with your thumb and forefinger. Lightly tap in. The bottom of the cylinder is beveled and guides the piston in. Take cylinder and piston and insert the rod, make sure the wrist pin clip is installed.
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Yup, just like Alf says.
It's not a bad idea to take a scrap of emery cloth or other grit paper and assure that things are nice and smooth at the very bottom of the cylinder so u don't go scratching the rings up when you slip them up in there.
I lube 'em with 30wt oil...
Good luck
rc
It's not a bad idea to take a scrap of emery cloth or other grit paper and assure that things are nice and smooth at the very bottom of the cylinder so u don't go scratching the rings up when you slip them up in there.
I lube 'em with 30wt oil...
Good luck
rc
worked like a champ. Cleaned up the bottom of the cylinder just to be safe. Use oil in the cylinder and on the piston. Lined up the piston ring pins with the intake. It all went together beautifully. Trying to get some pictures to upload but no luck yet. Speaking of luck. The studs on the intake are a 1/4" wider than the stock cylinder. Do you run into this much?
Thanks again for all your help.
Thanks again for all your help.
Good to hear, now for the intake studs, 1/4' isn't much, you can take a small rat tail file (like a chain saw file) and elongate each hole 1/8" or so.
That is how my RB80 kit from BGF is. It was claimed as having a larger intake port, but looks like it just has studs that are spaced farther apart than other models.
