The gearing on the 2015 SERG (32/68) rear belt was a lot better than the 32/66 of my 2007 SEUC. I did not want to go the swing arm modifications of going to a 30 tooth transmission pulley. I got the Andrews 31 tooth and found I had enough slot on the swing arm to get the belt tight. Unfortunately the HD rear axle cam adjusters are not high enough to get the full travel out of the rear wheel. I took both cams and added 3/16 square stock welded to the cam face to make the same cam profile but added 3/16 more adjustment. This took about 30 minutes and did not require removal of the swingarm, just removal of the axle.
Belt is tight and has a little more adjustment left if needed in future. The 3.5 percent final drive ratio change increased torque and acceleration. Instead of 78 mph at 3000 rpm, it now runs at 75 mph for 3000 rpm. A very low cost way to get a 3.5% gain in torque and a lower first gear for off line acceleration.
Speedo correction was simple with Thundermax ECM. Just told it the ratio change and it did all of the calculations.
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Topic: 31 tooth pulley on 2015 SERG (Read 1792 times)