In stock - Ships from Australia



Softail 1990-1999

Dyna 1991-1999

FXR 1990-1994

Features & Benefits:-

Got strong? We have strong! JIMS Fat 5 Overdrive is simply the strongest, toughest gearbox made. Period. JIMS took advantage of its new, more compact shifter technology to increase the width and strength of every gear. The width increase varies from 18% to 53%, depending upon the loads each gear set must carry. Big power is more popular than ever. Large engines like the JIMS 135’ deliver double the stock power and torque. When such power is linked to the ground through high torque clutches and big sticky tires, the peak loads on transmission gears rise far above what anyone but JIMS ever expected their trannies would need to endure. All are available with a mechanical clutch activated system only.

Fat Gear Superkits are shipped as a gear cluster installed into a trap door. All necessary shifting components, gaskets and unique components are supplied to be installed into anexisting transmission case.

Tech Tips:-

Fat Gear Transmissions are a CUSTOM application. Modifications to the exhaust bracket and 1993 to 2006 FL’s oil filler spout are necessary. Also, trans top lid will require shift lever clearance modification on certain models.


NOTE: Modifications to exhaust bracket is necessary as the transmission end cover extends approx 0.560in. fron a stock cover


Additional information