Well it all started as a little whisper from the Devil, “You need to see this new 5-speed kicker that bandit has, It’s from Germany.”
”Hmmmm,” says I, a kicker for the chop. I’ve been toying with the idea for the past couple of years, but I haven’t heard too many good things about the kicker kits that were on the market at that time. After I did a little research and got a look at the parts, it looked like the Müller set up was as good or better as anything out there. So as I went on about my project, much to the Devil’s snickering about kicking a 113 inches of growling stroker. I figured it didn’t look like too hard a job. Honestly, I’ve never been into a big twin tranny, but I figured, since I’ve played with 4500HP transmissions at work, this would be a snap.
First off you need to get the tranny opened up to pull the trapdoor. On my particular setup I went with pulling the case out of the frame because I couldn’t get the shifter drum and forks out with the oilbag in place. Remember to disconnect your negative battery cable to prevent your miniature meat grinding plant from firing up, if you accidentally engage the starter.
Remove the top cover, shifter drum and forks before pulling the gearset. Müller claims to have a puller for pulling the trapdoor off the gear shafts in the case, which is probably cool but in my situation it was just a quick trip over to the press for a little gentle encouragement and the shafts were free of their bearings.
It might be tempting to try and pop the shafts with a dead blow but your trapdoor bearings are ball rollers not designed to take any axial load. You most likely will damage the cages and/or races using a hammer. The Müller kit provides a modified trapdoor so the JIMS big bearing trapdoor I was running had to go.
Press your transplanted bearings into the new Müller trapdoor and secure them with their snaprings.Press the mainshaft and countershaft back into the trapdoor assembly. Torque up the countershaft nut with the original thin spacer washer to 45-55 ft-lbs. Now here’s where the English German translated directions get somewhat murky.
Replace the mainshaft nut with the supplied ratchet gear nut but omit the lock-washer. Well the original shaft nuts were nylock nuts with a thin spacer/washer behind them; so under speculation, I omitted the thin washer and mounted the ratchet nut on the mainshaft using red loctite. The Müller mainshaft ratchet nut is drilled and taped for a set screw and the directions dictate using it, but since it was conveniently missing, and I didn’t feel that running a set screw down on my mainshaft threads, it was omitted and red loctite was used. We installed the supplied kicker arm stop plate around the countershaft nut on the trapdoor.
Now the trapdoor and gear set assembly can be reinstalled into the case. If you choose to washout your case make sure to soak all of the set bearings with some assembly lube prior to reassembly.
Another confusing issue was the modification to the pushrod/oil slinger. The directions tell you to remove the pushrod end and change it according to the drawing. The drawing shows what looks like the thrust bearing machined down to 17mm.
In reality, what is required is to remove the snap ring, pull off the thrust bearing and oil slinger and turn down the slinger flange on the pushrod to 17mm (.669”). Reinstall your thrust bearing minus the oil slinger along with the snap-ring and your pushrod end is good to go.
Müller Motorcycle AG | Gerhard Peter
pete@m-motorcycle.de
The shifter assembly and top cover can now be reassembled and the tranny case put back into the frame. Make sure to check the shifting before going any further incase there is any binding in the mechanism.
The clutch cable is run through the outer cover and connected to the supplied Müller power clutch arm, which gives better leverage for those of us who need to run more clutch springs.
Mount the pinion gear sleeve inside the cover using loctite on all fasteners. Install the kicker shaft through the cover, mount the drive gear in the right orientation and add shims behind the snap-ring to eliminate any axial movement. Next the pinion gear and kick-out spring are mounted on the sleeve in the cover. Rotate the kicker drive gear so the pinion gear retract fingers keep it from springing off.
The cover is now ready for installation. Now this is where the Devil and I were scratching our chins. When I went to install the cover I noticed that there was some interference somewhere inside. With the cover loosely mounted you could tell something was rubbing on the countershaft. Initially we thought that the kicker shaft was rubbing on the countershaft. After many test fits, I took some stand off measurements and came up with around .030-inch clearance between the two ends. Upon closer examination of the countershaft end I noticed some scratches that swept across its face.
It seems that since the kicker shaft and countershaft are offset from each other, the pinion gear retract fingers on the drive gear cross over the countershaft during rotation. I used some poor-boy tool dye ie. Sharpie marker, on the retracted fingers to show me where the interference was. Several passes with a cutting wheel along with several refits and no more interference.
It seems that the retracting fingers could stand to be made with a slightly thinner material to avoid machining for clearance. With everything fitting nicely and rotating smoothly, the cover was ready to bolt up. The directions suggest mounting the cover and torquing the bolts at half torque, kicking through several rotations, then final torque up to spec. That allowed the parts to seat before we tightened them the final time.
One thing we may want to mention is that the clearance issues may be due to the fact that he has a JIMS tranny, that had the oversize bearings and not an H-D 5-speed? Too bad we didn't have a stock 5-speed laying around to check that out.
–Kent
The components of this kit seem to be well made and the cover itself is a beautifully cast and machined piece that must have spent a considerable amount of time on a CNC mill. The kicker arm is extra-strength, solid and will definitely hold up to my fat ass jumping up and down on it. The pedal is somewhat lacking in style but as soon the Devil modifies my exhaust, I’m going to Fab Kevin for a one-off brass pedal, I have in mind.
I’ll keep you posted on how the huffing and puffing goes as I fire up that 113-incher, and how much snickering I get from the Devil, if or when she wears me out. Big thanks go to the Devil for helping out with this project as well as letting me take up some of his space at his lair.
Their website is :
Respectfully submitted,
–Spanky
To order write:Müller Motorcycle AG, | Gerhard Peter
pete@m-motorcycle.de
