Rubbermount_EFI Now running 3.40 factory gearing

[cliffm]

I recently converted my 2012 XL883 superlow primary gearing from 883-34/57 to 1200-38/57 and kept my previous mod of 30T/68T belt combo. This is after Hammer Performance 883/1250HP conversion w/stock heads.

I had updated the rear tire size from "factory" 150/60-17 to 160/70-17.

All of the changes dropped my final drive ratio/highway RPM and I couldn't be happier! 4th gear is now equivalent to my OEM configuration 5th gear, making it much more usable. I find myself using 2-4th more than I ever did.

I still have roll on throttle, even with a tall windshield, but no longer use 5th until i'm going at least 65MPH. Most of my riding is single, freeway jaunts, with some mixed in backroads.

Recently I got 201.6 miles on 3.72 gallons, keeping the RPM mostly at 2800-3400 range at any given speed, per posted speed limits.

For those running two up, this might be too tall and should stay with the 29T/68T combo (3.517) or for more punch the 28T/68T combo (3.64)

I definitely no longer look for the imaginary 6th gear anymore, sometimes happy cruising along in 4th.

[cliffm]

Having had a 2002 BUELL S3T, the 3.40 gearing is still lower.

Riding the Buell, I hardly ever used 5th unless over 75MPH, and starting out from a stop felt like I was in 2nd gear.

The sportster 3.40 gearing is a great compromise between the two.

[gconnsr]

I just did the primary gearing on my 2016 and I'm pretty happy with it.

[kitabel]

The 1936 factory big twin 4-speed transmission ratios are still an excellent choice today: big 1st gear, strong progression, and close 3-4 shift.
1st 3.00:1
RPM drop to 2nd: 39% (6,000 shift recovers to 3,635)
2nd 1.82:1
RPM drop to 3rd: 33% (6,000 shift recovers to 4,048)
3rd 1.23:1
RPM drop to 4th: 19% (6,000 shift recovers to 4,887)
4th 1.00:1