Engine RPM change if I rebuild a 96 to 103?

[jimharvey1]

When I test rode an Ultra prior to me swapping my '07 Super Glide Custom (96" w/ 6-speed) in for an '07 Ultra Classic (96" w/ 6-speed) I immediately noticed, and mentioned to the salesperson, that the Ultra was a DOG compared to the peppiness of the Super Glide. He attributed it to the additional weight (which logically made sense), but if the Super Glide had a different set of gears or final drive ratio, that would further explain it. Boring out the motor, however, won't make a difference in the final rpm/road speed ratio, however, if done correctly, especially with the correct cams, you will feel a considerable difference in getting to that desired road speed when you twist its ear. :s

 

[BUBBIE]

My 09, bored to 103"(actually 95" bore from 88" size)

The .375" or 3/8" Longer Stroke makes the engine 103"...

I used pretty stock set of heads that were Blueprinted by Don Dorfman of "Dewey's Heads"

Installed manual PR Valves. Some porting intake and smoothing here and there. Proper angle grinding of the valves to Flow better and trimming down the heads to even out the CC number to be exactly the same.

Heads:
take-offs from an 08 SG. They were UN-Balanced from HD... from each other by a bunch.... Probably not matched coming from the production shelf :guitar

New SE255 cams and gaterman lifters.(GREAT LIFTERS)

Bored and fitted piston and rings PROPERLY by prodrag1320 Kirby
using SE flat top pistons (teflon coated)(short Little Tuna Cans):newsmile100:

IF NOT a good machine shop doing this work, you can get Early-On Piston slap.

Finished off Using .030 head gaskets. Torqued heads to 43#

Here at 4400 feet elevation the CCC runs at 185# and should be at 207# at sea-level....

Elevation is one thing YOU should take into consideration when building....... WHAT elevation you run the bike... Does make a BIG difference...


NOW ABOUT RPM'S:

RPM's Changed BECAUSE the gearing of the 07 and ? on 08 models HAS been changed to allow more usable power in 6th gear..(not as High Geared)

signed....BUBBIE

 

[BUBBIE]

Adding this to clarify my statement above:

The gearing change was in the Newer bikes as the 07 and ? 08 Had too Tall a gearing in 6th. Most 96" riders complained about the lack of Power in 6th gear Doing The Speed Limit..and the need to go Over the speed-limit to use that 6th gear..... One comes to Mind HUH :bigsmiley18: EH geezer....... No ticket though.....

SURE, A No-motorcycle Cop is going to believe that Gearing Story....:lolrolling

signed....BUBBIE

 

[dolt]

The "big deal" is 500 RPM difference.
The '07 Dyna ran 3,000 at 70 MPH.
My '07 Ultra runs 2,500 at 70 MPH.

I may have to check gear changes.
Both bikes have 6-speed trannys.

As others have pointed out, there has to be a difference in the final drive ratios between the two bikes. Could be a primary, secondary or a combination of both but the final drive ratios are different. The only way you will be able to tell is to pull the primary cover and count the teeth on the motor and clutch sprockets as well as those on the tranny and drive belt pulleys and compare them.

I assume you are comparing rpms in 5th gear? The final drive of the '07 six speed is 2.790 which, at 3000rpm will move you along at about 82mph.