Any experience with JE pistons?

[Scholle]

As I have already reported elsewhere here in this forum, I'm just about to revise the engine of my Rocket 3 from 2005.

Among other things, I decided to install JE pistons with a compression ratio of 10.5: 1.

I have noticed that the new pistons have a comparatively large piston clearance of 0.9 mm. The stock pistons have a piston clearance of 0.02 mm.

I think this is so intentional and essentially based on the fact, that the JE pistons are made of 2618 T6 forged aluminum. This material has a greater coefficient of expansion than cast aluminum, which the standard pistons are made from.

I'm afraid that the engine will rattle when cold and will run quiet only when the engine has become warm.

I also fear that oil consumption will increase.

My question: Has any of you already had experience with JE pistons? What about oil consumption, engine noise and reliability in general?

 

[Scholle]

As I have already reported elsewhere here in this forum, I'm just about to revise the engine of my Rocket 3 from 2005.

Among other things, I decided to install JE pistons with a compression ratio of 10.5: 1.

I have noticed that the new pistons have a comparatively large piston clearance of 0.9 mm. The stock pistons have a piston clearance of 0.02 mm.

I think this is so intentional and essentially based on the fact, that the JE pistons are made of 2618 T6 forged aluminum. This material has a greater coefficient of expansion than cast aluminum, which the standard pistons are made from.

I'm afraid that the engine will rattle when cold and will run quiet only when the engine has become warm.

I also fear that oil consumption will increase.

My question: Has any of you already had experience with JE pistons? What about oil consumption, engine noise and reliability in general?

Thanks to the "man in the tin shed" I found the explanation. I did the measuring of the pistons diameter close to the pistons ring area, and that´s the wrong method. It should be measured close to the bottom of the piston`s shirt. And that is fine. The diameter there is 101.56 - 101.58, at the opposite end it is 100.62 mm.
Many thanks to Neville.
Georg

 

[lunatic]

As I have already reported elsewhere here in this forum, I'm just about to revise the engine of my Rocket 3 from 2005.

Among other things, I decided to install JE pistons with a compression ratio of 10.5: 1.

I have noticed that the new pistons have a comparatively large piston clearance of 0.9 mm. The stock pistons have a piston clearance of 0.02 mm.

I think this is so intentional and essentially based on the fact, that the JE pistons are made of 2618 T6 forged aluminum. This material has a greater coefficient of expansion than cast aluminum, which the standard pistons are made from.

I'm afraid that the engine will rattle when cold and will run quiet only when the engine has become warm.

I also fear that oil consumption will increase.

My question: Has any of you already had experience with JE pistons? What about oil consumption, engine noise and reliability in general?

I just installed 10.5:1 JE pistons and cant hear and any engine noise when cold... I only have about 200 miles on the new pistons so I cant comment on oil consumption, but I cant see why it would. My stock pistons only measured .0008" - .001" larger than the forged JE pistons.

 

[Scholle]

I just installed 10.5:1 JE pistons and cant hear and any engine noise when cold... I only have about 200 miles on the new pistons so I cant comment on oil consumption, but I cant see why it would. My stock pistons only measured .0008" - .001" larger than the forged JE pistons.

Did you just replace the stock pistons or did you change anything else, e. g. cams ? Did you check the performance on a dyno?
Regards, Georg

 

[lunatic]

Did you just replace the stock pistons or did you change anything else, e. g. cams ? Did you check the performance on a dyno?
Regards, Georg

I installed pistons,lush drop in cams,springs, ram-air,carpenter sidewinder exhaust and PV5 with auto-tune. No dyno numbers yet.