Last month we left you with some info about the Baker DD7 transmission.
We talked a little about gear ratio, and what to expect when you get the DD7 kit from Baker. The disassembly and reassembly went pretty good, everything went as planned and like Baker said, we did not have to grind or shim anything.
Basically pull one out, install the other. I did find my throw out bearing was junked and laying in my side cover but no big deal, I replaced it with a Baker heavy duty kit. This should handle things a lot better. The part # is TBK-56L and runs about $80 and comes with everything you need.
Installation starts by installing the new bearing into the transmission case. We use the George’s main drive gear bearing kit #620200.
We recommend putting a little WD40 on the o-ring of the main drive gear before installing it. The driver from the George’s kit goes on the gear first.
It then gets pulled into place from the other side of the case with the other half of the George’s gear installer kit.
Next, the main drive gear seal is installed using the George’s tool #620520. A few taps gets it shouldered in place.
We are now ready to get things prepared to slide the gear set into the case. A little oil again on anything that looks like it might fit into something.
Fit the trapdoor gasket over the gear set before you install it and cut the zip tie that is holding the shifting assembly in place.
At this point, we can slide the assembly into the case. There should be no obstruction and other than rolling the shaft a small amount to get it to seat, you should not have to bang on it.
With the gear set in the bike, we can now install the trapdoor hardware. Baker provides nice 12 point bolts and we use a small dab of blue Loctite on them.
The instructions tell you that these bolts are to be torqued to spec by sequence. This info is available in your service manual.
With the trapdoor firmly in place, we can now install the inner primary bearing race. This is where the 3mm measurement from part one comes into place.
Here we are installing the thicker gasket provided by Baker for spacing the vehicle speed sensor. This spacing makes recalibrating the speedometer easier and must be used.
With our new gasket in place, we can install the new top cover for the transmission. Again, small dabs of blue Loctite are applied to the 12 bolts from Baker.
When we pulled the stock throw out bearing, it was trashed. We decided to replace it with the Baker heavy duty throw out bearing.
This is what you get in the kit: a gasket for five and six speeds (fits ’83 and up), thrust washers, heavier bearing, ball bearing, and two clips in case you send the first one flying. You can see the size difference in the bearings above.
You have to start by taking the oil slinger off of your clutch rod.
You assemble the throw out bearing as instructed. Use some oil in this step.
Now we place the throw out bearing in the trapdoor and remove the ball and ramp from the transmission side cover.
Keep the barrel connector at the end of the clutch cable as it will be used in the reassembly.
The bottom part of the ramp has a tab and lines up with a slot in the side cover. A little wheel bearing grease will help hold the bearings in place.
Place the bearings in the center of the slots. Then the clutch cable is attached to the top half of the ramp. It goes on, the snap ring behind it.
Now we use the 12 stainless 12 point bolts supplied by Baker. The smaller of the two will be for the top of the side cover. These also get torqued to spec.
Now we can reassemble the rest of the components: the primary,
exhaust, etc. Top off all fluids; we suggest Spectro primary case and 6 speed transmission oils. We can now begin the road testing.
After we got the bike buttoned back up, it was time for her maiden voyage. It happen to be raining that day but that was fine because that would let me feel her out and keep me from running hard from the get go. So I took her down the road for a few miles and then returned to inspect things and make sure I had no leaks; all was good. My first impression was a real good one from the time I dropped her into first gear and let the clutch out. I noticed she didn’t clunk as loud and she caught me off- guard when I let the clutch out for the first time. I was used to feathering the clutch a lot to pull out and winding her up to get her rolling.
Not anymore. I let that clutch out and she hooked up real good! I thought to myself: I am going to like this. The next day, I had plans to roll with a couple guys to central PA. which is a beautiful area to ride and test this transmission out since it has mountains and turns that you can really enjoy.
We took the highway out there which let me see how 6th and 7th felt and I must say I liked it. Sixth gear was exactly what I was looking for. It kept me from running real high RPMs in the old stock 5th gear or lugging the old stock 6th gear. One of the things I hated in the old tranny was the fact that I didn’t have a comfort zone between 5th and 6th. When I would be in 6th with my old tranny, I was running about 80 mph and that was my bike’s comfort zone. Now I have more options in comfort zones at any speed. Baker was right in saying you’re always in the power band, and this my friends is what the “FTW Express” needed most. The shifting between gears was real smooth and the harder I ran her, the smoother it shifted. It is definitely a quieter shifting transmission which is due to a difference in main shaft weight. The stock main shaft has 1st thru 4th as part of it, meaning if one of those gears gets damaged you replace the whole main shaft. This also means the shaft weighs over 5 lbs. Baker only incorporates 1st gear on their main shaft, which weighs a little under 3 lbs. That translates into a big difference in inertia at 3000 RPMs, thus quieter shifting. I also noticed the DD7 is a quiet tranny compared to the stock one. About the only place I can hear any noise is when I wind 3rd gear out some, but it’s still not real noisy like the old 5th was.
Baker kept the DD7 noise under control by the way they designed the gears. First gear is a 5 degree helical cut. This keeps it quiet compared to the stock 1st, yet keeps it a strong gear for pulling out which is a day and night difference to how the stock one performed. My ol’ lady even noticed that. She said she noticed how much better it pulled out, especially from a dead stop on an uphill. Sometimes it felt like we were in 2nd gear and this is a huge improvement when riding two-up and loaded down. Now 2nd and 3rd gears are straight cut for strength. The 4th, 5th, 6th, and 7th gears are 18 degree helical cut for noise control. I must note that my bike did not need the speedometer recallibration unit because of the Thunder Max ECM I use. The Thunder Max has a speed calculator incorporated in it so all I had to do was find out how far off my speedo was. I hooked it up to my laptop and the bike, went to my basic settings area and then went to my speedometer setting to access the calculator. Here it will let you enter the actual speed you are going and the speed your speedo says your going. It calculates and gives you a new number for your speedo setting. It’s that easy.
I now have around 3000 miles on the Baker DD7 and it has performed flawlessly. It did everything they said it would and more. It really brought the “Express” to life. I would like to thank Bert Baker for the opportunity to do this article and Scott at Baker for helping out when needed. The people at Baker Drivetrain will take the time to answer any questions you have on their products and yes, it’s Made in the USA. Till next time, ride like it’s your ex’s bike! I sure am.
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