New pistons and connecting rods.

I wanted to use the new Hepolite pistons because as the oversizes grew the dome was expanded to make up the crown difference. Others didn't do this as they just change the diameter and leave the head alone. Now, my problem is I cannot remember how the original Hepolite looked so I do not know if this is a large head or not. Talk to a supplier for information. However, I used these as they were much lighter.


The problem is the top rings are chrome. I decided to use Hastings iron rings as they are the same size.


I bought a pair of pistons from an English supplier. They are German made Nüral. Very well made. However, they each weigh 15 grams more than the Hepolite. Go for the lighter Hepolite pistons.


Here are Hastings rings on Hepolite pistons. The markings are the diameter of the piston at the bottom. The ring gaps on both are: top ring - .018, middle ring - .024, oil bottom ring - .018 thousandths. See what is quoted from the BritBike forum: Mr. John Healy's Brit Bike forum info regarding rings: HERE


The number on the crown of the pistons is the weight in grams. They were one gram off. Try to limit it to 3-4 grams, industry standard. Better to take a little off the inside of the piston to even it out. Same for rods.

The weights

These are the gallery of pictures. Click one. At the bottom of the pics may be a menu to bring you back here or go to the Homepage. Later in a restoration they may be worthwhile.


Printable Link

Previous Page | Main Page | Next Page