Transmission ratio

[deltafarmer]

Just a quite evening at home ,so I was looking at HD site and reviewed the differences in ratio between the 08 and the 09  Ultra. I was just curious as to what the actual result would be.  (were they trying to offset the difference in weight,38# dry).  Also, was the difference achieved with the rear sproket only?   Just questions to pass the time on a wet evening.   Thanks!!

[autoworker]

Did the 08s have 2.79 final drive ratio?

[springer-]

The 07-08 transmission gear ratio info on HD's website is wrong.  In 07 I theorized the info was wrong while developing a gear ratio calculator.  I disassembled an 07 transmission and counted all the gear teeth and came up with the correct ratios.  In 08 they published the same wrong info.  In 09 they fixed the incorrect gear ratios.  Also in 09 they went to a 68 tooth rear sprocket up from a 66 from 07-08.  This does account for the difference in the overall drive ratio.  You can find all the correct info and "play" with many changes to see the effects they have on our Gear Ratio calculator found here ... http://www.bigboyzheadporting.com/calculators.htm

[springer-]

Did the 08s have 2.79 final drive ratio?

Yes

[autoworker]

I hear you Springer...they list the wrong ratio on my 07 FXD in the service manual.The owners manual listed the correct ratio.

Now they are both wrong in my case beacause I "fixed" it with a new clutch sprocket.