I think I understand this...but just want to throw it out there to confirm.

a 2001 roadking with a 88 twin cam engine has a bore of 3.8 and a stroke of 4.0.

a 2007 ultra with a 96 twin cam has a bore of 3.8 and a stroke of 4.4.

So if I were to upgrade the 96 to 103, the jugs and pistons would have no value on the 88, since moving the 88 to 95, would take the same jugs and pistons that were used to bring the 96 to 103. on the 88, the 103 jugs would bring the bike to 95. The 96 jugs and pistons are basically useless in this senerio.

unless I changed the crank on the 88.

 

Yes. Almost grabbed a new take off set off ebay before I relized this. 96 and 88 uppers are the same. Harley needed more torque for the 6 speed.

 

10/4 thanks....

this bore and stroke stuff gets confusing if you don't pay attention to it. the helicopter mechanic in me would have thought as smaller stroke would have given harley more torque

maybe thats why the 95 is such a kick *** engine.

 

Stroke=leverage which =torque

 

You can convert an 88" to 95", using larger cylinders and pistons, but my understanding is they will be different part numbers than those on a 96". I am sure there are some engine specialists out there who can sqeeze a little more out of them. The helicopter mechanic in you can still have more lift-off if you wish!

 

My 2011 RKC has a 103 w/ a 3.875 bore and a 4.38" stroke. According to the HD website.

To go to a 110 would I simply change out the crank? Giving it a longer stroke?
even though the B&S on the CVO 110 is 4" & 4.38" ?

A 2011 RK has a 96" engine w/ a B&S of 3.75" 4.38". Would you do likewise - change out the crank? - to make it a 103?

By making any of these changes do you need to change the head gaskets and bolts to ones that will withstand the added pressures?

 

The 110" is 4.000 bore X 4.375" stroke . so the increase to 110" comes from the larger bore . The bore increase requires a case drill.

 

The piston pin is located differently in the piston on a 96 to 103 big bore piston kit then that of a 88 to 95 big bore kit due to the longer strock of the 96 engine

 

[QUOTE=Matt0987;8707004]My 2011 RKC has a 103 w/ a 3.875 bore and a 4.38" stroke. According to the HD website.




A 2011 RK has a 96" engine w/ a B&S of 3.75" 4.38". Would you do likewise - change out the crank? - to make it a 103?



No, not the crank, just change the bore to 3.875