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Tuesday Edition

There Is New Life For Your Screamin' Eagle 6-speed Transmission

With the Help of the JIMS Crew

Photos and text by Steve Bauman


A little history. The motorcycle is a 2004 Electra-glide with some performance upgrades, one of which was a Screamin Eagle 6-speed installation. At the time of the failure there were only 33,000 calm miles on the trans.

The day of the failure I was riding with a buddy and the bike gave no hints of a problem. The only thing I noticed was when I glanced at my speedo there were a couple times the needle would fall and then come back. I just attributed it to an electronic glitch, nothing to worry about right.

We broke off on our separate routes home and I pulled off the freeway to get gas. As I was pulling into the gas station the bike started to make a hellacious screeching noise. I didn't have a clue what the fuck it was. I put it in neutral and it still made the noise, so my first thought was a problem in the primary.

I shut the bike off, pulled off the derby cover and chain inspection cover and didn't see anything that was obviously wrong. I started the bike back up and the noise was gone, so I put the two covers back on, got my gas and took off figuring I'd deal with the noise later.

I'm getting back on the freeway, going through the gears and everything seemed fine until I shifted into 5th gear, nothing. I thought I'd missed the gear, so I down shifted into 4th, back into 5th, nothing, shifted into 6th and nothing. I went back down into 4th and rode the bike home, that was a long 80 miles.

On to the fun.

When I got home I pulled the outer primary and everything looked to be OK, so I removed the trans drain plug, nothing drained out. I'm thinking what the fuck! I removed the dip stick and it showed full. I took a screw driver, poked it up into the trans drain hole and it started to drain along with a lot of metal shavings.

Obviously this isn't good. Next thing was to remove the trap door cover and it got worse.

The next step obviously was a major tear down. The outer primary was removed and on with the tear down. I put my clutch basket puller on the basket and it wouldn't budge. It was so tight I stripped the threads of the puller jack screw.

All my other pullers have ¾-inch jack screws instead of 5/8-inch, so I bought a grade-8 nut and tacked it onto the puller. I also had to drill additional holes in the puller hub to work with the Bandit Machine clutch basket.

I'm thinking good to go, but nooooooooo; the basket still won't budge. Now I'm thinking I'm missing something, so I down load the installation instructions from the Bandit Machine web site and there is nothing other than it says to use a light coating of oil on the trans shaft when installing the basket and a couple drops of Locktite on the threads.

I take a closer look at the exposed splines of the shaft and see what appears to be red Loctite so out comes the propane torch. After applying what seems to be a lot of heat the basket finally released.

Whoever installed this clutch didn't just use a few drops of Red Loctite, the dumb fuck coated the whole shaft and if you notice, not a drop of blue Loctite on the threads as per the instructions.

I also discovered a damaged compensator shaft extension. 

So now it's on to the trans disassembly. I got the trans cover off and it was apparent I was fucked. After I got the bent shifter fork rod and the damaged shifter forks out, the damage was becoming even more obvious.

Next thing was to remove the trap door with the gear clusters. So off comes the inner primary. I might add here, if you don't have the puller (JIMS Machine) for the trans main shaft bearing race you're going to hit a wall.

I removed the trap door assembly (both bearings were very tight from damage) and got a couple surprises. Just about every single gear on both shafts was damaged along with a shifter dog that looked like a pizza cut into slices. No wonder I didn't have 5th or 6th gears.

You can see that the shifter fork rod boss has been removed from the upper center of the case for the installation of the Screamin’ Eagle 6-speed per Harley’s instructions. I'd like to know what idiot in engineering came up with this complete brain fart. This becomes a major issue later. The trans main drive gear and counter shaft bearing haven't been removed yet.

A few photos of the case cleaned and all bearings and seals removed. 

Now the interesting part. Since I only got 33,000 miles out of the Harley trans, I decided why tempt fate with another of the same, so I looked at Baker and JIMS.

Another factor that contributed to my decision not to go with another Screamin' Eagle gear set is because when my brother Tom, who is a professional, licensed metalurgist looked at the gear dog he said that the heat treatment of the part was sub par to say the least and that was without doing any testing (Just looking at the fractured parts with a naked eye),

An aside here about the Harley trans: Harley only guarantees it if it's installed by a certified dealer, nuff said right.

The Baker comes with a 5-year 50,000 mile warranty and they also offer a 10% veteran discount, but they're a bit pricey. JIMS comes with a 6-month warranty (wow, right) but fit my budget better.

So I call JIMS and tell them the story, and as soon as I mention the Screamin' Eagle trans I'm told I'm S O L because of the shifter fork rod boss being removed, fuck.

So I called Baker and it's the same story. Wow, what to do now. I thought before I started looking for a used trans case or bought another Screamin' Eagle trans set I'd get the JIMS kit and see what was what.

It's a very quality looking product and comes with all the parts (except one, which I'll touch on later), gaskets (except a primary cover gasket) and seals for the job.

After looking at the parts I thought there is a way to make this work using the same method as the Screamin' Eagle, so I decided to proceed.

Photos of the case with the new bearings, seals and shifter ratchet assembly installed.

On the Screamin' Eagle 6-speed Harley uses the trap door to support the shifter fork support rod and has a threaded hole that an Allen head set screw is used to keep the shifter fork support rod from coming out. My thought was why not do the same on the JIMS? This is where I took a leap of faith.

I took the Screamin' Eagle trap door set it against the Jims trap door (after removing both trap doors from their gear sets), marked where the hole for the support rod should go, set it up in my drill press and bored the hole.

I went through my box of bushings and found the perfect bushing. A hardened bushing with a 1/2 OD and 3/8 ID, perfect. I set the bushing in with Red Loctite.

Some of his shots were out of focus...
Some of his shots were out of focus...

I did a test fit to see how it all worked and everything seemed to be fine. 

The next issue was how to keep the rod from walking out. I went on line and found a place that carries chrome moly rod and will cut it to length so I ordered a 12-inch piece.

JIMS rod along side the new longer rod yet to be cut to size. 

The longer rod inserted through the trap door and then after it was cut flush with the trap door. 

Next issue was one I had already sorted out, keeping the rod from walking. There is a relief at the top inside of the trap door that is inline with where the rod is. I could have cut the rod a bit longer and allowed it to extend out to the inside of the trap door but decided it would look like shit so I decided to make an insert and set it in with JB Weld after using a burring cutter on the inside of the cover.

I love that shit!!

Next was assembling the trans and manually checking the shifter mechanism, which worked flawlessly.

I ended trimming the head pipe bracket so it would fit the Jims trap door and just left the threaded tab that the engine ground attaches to. 

Final assembly hit a snag though. The oil filler spout wouldn't fit. After rereading the instructions it mentions that on some installations a spacer is needed on the oil filler spout for it to clear the larger JIMS trap door and speedo sensor plug, and some models will need a modified the crank case vent tube location. I found a much thicker spacer online than the skinny ass one JIMS and Harley sells. It took care of all the clearance problems, without having to modify the spout or line.

I might add here that after seeing the damage to the crank compensator extension I purchased and installed a Hayden hydraulic primary chain tensioner. Forgot to get a photo of that.

JIMS said to fill the trans with 80-90 gear oil for the first 500 miles and then switch over to a synthetic. I'm not a big fan of synthetics (a very expensive failure using Amsoil for big twins) so I'm going to use a good quality gear oil instead when I change it.

The one issue you need to address if you go this route with the JIMS kit is realizing that as soon as you modify the trap door it voids the warranty. But with a warranty that only goes 6 months who gives a fuck right.

If anything went wrong I'd have a friend order a JIMS trap door and swap it over. I've got about 300 easy miles on the bike and so far am very happy. Right off the bat the trans shifts easier, is quieter (both of which might also be attributable to the Hayden kit) and it’s much easier to find neutral.

I've got a Zippers Thunder Max tuner, so I do need to plug it in to my lap-top and recalibrate my speedo; it's about 12 MPH too high.

All in all I'm very happy and only time will tell if I royally fucked up or not, but so far so good.



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