JS Motorsport Technical
Ultralight rods and pistons for Solid frames

The bushless ultralight rod below was designed for short stroke 500 classic racers, 500 to 650 Dominators, 750 solid framed bikes such as the Atlas and all long stroke 750s up to 75 hp. They weigh 10 grams less on the small end than our regular bushless rod. Small end = 95 grams. Big end = 307 grams. This ultralight rod provides maximum smoothness for solid framed bikes. Crank rebalancing required.  DLC pins only.

ultralight rod

66 – 68.5mm flat top pistons for 500 Dominator

The 66 to 67.5mm flat top pistons are approx 7.5 C.R. for a 500cc Dominator. These pistons weigh about 170 grams and go with our Ultralight 6.4″ length rods.

68 to 69.5mm flat top pistons for 650 SS Dominator

The 68.5mm flat top piston is refered to as 9:1 C.R. (closer to 8.5:1 C.R.) for 650SS Dominators. These pistons weigh approx 170 grams and go with our Ultralight 6.4″ length rods.

69mm flat

66 – 68.5mm Hi C.R. domed pistons for 500 Dominator

The 66 to 67.5mm centrally domed piston below is approx 9:1 C.R. for a 500cc Dominator. These pistons weigh approx 170 grams and go with our Ultralight 6.4″ length rods.

67mm 170gm pistons

68 – 69.5mm Hi C.R domed pistons for 600 & 650ss Dominator

The 66 to 68.5mm centrally domed piston below is approx 10:1 C.R. for 600 Dominators. These pistons weigh approx 170 grams and go with our Ultralight 6.4″ length rods.

69mm dome

The bottom side of the dome is 3D undermilled to achieve minimum weight as in the photo below.

domed underside