Oh my! Bert Baker’s grudge is finally out in the open – that is to say that after two years of development and testing, refinement and re-testing, Bert Baker’s ‘GrudgeBox’ 6-speed overdrive builder kit is finally on the open roads!
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| Stock (left) GrudgeBox Street (right) |
Described as being built to “take the high horsepower abuse found in late model H-D performance applications while providing elegant shift precision,” there are two configurations offered for 2006 and later Dynas and 2007 and later Softails and Tourers.
GrudgeBox ‘Street’ has straight cut 1st, 2nd and 3rd gears, helical 4th, 5th and 6th, “designed and geared for everyday highway riders with modern H-D horsepower.”
The straight cut 1st, 2nd and 3rd gears are for “efficient torque multiplication,” with the helical 4th, 5th and 6th gears delivering “smooth and quiet cruising” with a 250 rpm drop at higher highway speeds (approx. 80 mph). The engineering focus is on “excessive durability” with a patent pending “bulletproof” main drive gear bearing and gears up to 40% wider than stock.
“mod-free install”
With positive dog tooth engagement in gear (pie shaped shift dogs), frictionless linear detent shift system (for smooth shifting), redundant neutral detent (to make it easy to find neutral), low effort, single axis/linear motion ratchet pawl (for crisp, tight and easy shifting) and greater durability than stock, one of the most extraordinary things about Baker’s ‘Street’ and ‘Strip’ GrudgeBox designs is that they require absolutely no, as in zero, zip, zilch, nada modifications to the stock cases.
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| GrudgeBox Strip |
The GrudgeBox ‘Strip’ gives you straight 1st, 2nd, 3rd, 4th, 5th and 6th gears – “designed and geared for performance buffs, racers and speed freaks seeking negligible power loss.” Having all the gears straight cut results in “negligible parasitic power loss, providing maximum power transfer to the rear wheel.” It has wide ratio gearing for heavier performance applications and is built for aggressive takes offs and long distances at above average speeds.
“reliable, smoother shifting”
The 4° back-cut angle on all GrudgeBox shift dogs ensures positive gear engagement and eliminates hop out (“more hook for the hold”) and the shift drum utilizes a fixed spindle design for smooth, low inertia indexing. “It’s easy to find neutral with our redundant neutral detent, which is incorporated into the architecture of the shift system.” There is a smooth linear 11/32” detent ball bearing riding on 60 micro ball bearings, with linear motion controlled by a caged 24 micro ball bearing assembly and a 44lb/in compression spring.
Baker says that “conventional shifter pawls have a 2-point pivot system. Our new low effort single axis/linear motion shifter pawl rotates from one central pivot point, allowing continuous motion throughout the shift with over-shift inhibitors preventing any missed shifts.”
“torque, torque and more torque”
A speedometer reluctor ring sends the vehicle speed signal through the stock speed sensor, keeping the pulses per mile the same as stock. The stock speedometer will indicate the correct speed without the use of a recalibration box (PCM reflash is required for correct gear indication and proper cruise control operation).
Intended for high horsepower applications and well suited for everyday cruising, the pie shaped shift dogs used in the GrudgeBox provide significantly more dog tooth/pocket landing area for positive dog tooth engagement while in gear. Baker’s exclusive patent pending double tapered roller bearing assembly eliminates the all too common stock main drive gear bearing failures.
“Conventional shifter pawls have a 2-point pivot system. Our new single axis/linear motion shifter pawl has fewer points of motion and will hold up under high horsepower and aggressive shifting.” The Baker GrudgeBox comes with a 5-year/50,000 mile limited warranty “for excessive torque capacity, crisp shifting and worry free, aggressive riding.”
BAKER DRIVETRAIN
www.bakerdrivetrain.com