Baker DD7 7 speed trans

[micbear]

Has anyone had a chance to install a Baker DD7 Trans?
It's A 7 speed trans, for HD 6 speed replacement, and really sounds sweet, but not cheap.
Its sad Harley owners have to put up with clunky transmissions from factory.
micbear

 

[onebadeagle]

I would think unless you have major engine upgrades it would be a hard pull in 7th gear. I don't think a stock triglide could handle high gear without lugging engine. Just my 2 cents I could be wrong

 

[msocko3]

I would think unless you have major engine upgrades it would be a hard pull in 7th gear. I don't think a stock triglide could handle high gear without lugging engine. Just my 2 cents I could be wrong

The DD7 7th gear is the same final drive ratio as the stock 6 speed. The DD7 just spreads the gear ratios out a little more and makes 1st almost like a grandma gear.

 

[micbear]

I never said I had a stock trike!
I just hate the clunky Stock trans and was trying to get a feel for a good review on DD7 trans cause it sounds very nice and may be the answer to a pour design by HD.
mic

 

[GoSlo]

The DD7 7th gear is the same final drive ratio as the stock 6 speed. The DD7 just spreads the gear ratios out a little more and makes 1st almost like a grandma gear.

Maybe that lower first gear is so you could do the hill climb in Sturgis? Could be a a new class: "trials-trike"!

 

[GARYD]

I like the big clunky sound of shifting gears - that lets me know I'm riding a real motorcycle and not some "wonderful, quiet, problem free" jap bike.

As long as there is no major damage being done, I don't have a problem with the sound. ThumbUp

 

[rap47]

I like the big clunky sound of shifting gears - that lets me know I'm riding a real motorcycle and not some "wonderful, quiet, problem free" jap bike.

As long as there is no major damage being done, I don't have a problem with the sound. ThumbUp

Ya, I agree with you on that. These trannys are pretty heavy duty and it will let you know that you are in the next gear. Been riding these 6 speeds along with a group of friends with the 6 speeds since they came out. Not one has had a problem with them.

 

[Pegasus1300]

So I guess the answer is "No, no one has any experience with that transmission" ? It would be nice to see a comparison of gear ratios in the Baker vs Harley

 

[micbear]

Info on web

The factory 6 speed has a 1 piece mainshaft with gears 1-4 machined out of one forging. This is easier and cheaper for high volume manufacturing, but yields a mainshaft that weighs over 5 lbs. This heavy one piece design is largely responsible for the clunk heard on every shift. This heavy rotating mass crashes into the gears on every shift. The DD7 has a 1 piece mainshaft (8620 steel) that only incorporates the small diameter 1st gear and weighs 3 lbs less than the stock unit. Whereas the stock gearsets utilizes a straight cut gear for 1st, and helical for 2-6, the DD7 uses straight cut 2 and 3rd gears, with the remainder being of a helical design. The largest amount of torque is put to the ground in 2nd 3rd gear, and straight cut gears handle that power the best. There is a not a lot of cruising going on in these gears, so the strength benefit of straight cut teeth outweighs the noise reduction factor inherent with a helical tooth design. The stock gears have tooth profiles that are cut on a shaper machine after heat treat, the BAKER gears are shaper cut before heat treat then precision ground with diamond coated tooling after heat treat (58-62 Rockwell ‘C’). This extra steps ensures not only a quieter gear pair, but enables much tighter backlash control. Further enhancements have been made to the male-female dog tooth pocket interactions, the tightened up radial gap on our design reduces the on-off throttle lag time and gear clunk noise found on the stock transmission.


DD7 Gears vs Stock


DD7 Gearset Layout

DD7 Ratio Stock Ratio
1st Gear 3.76 1st Gear 3.34
2nd Gear 2.75 2nd Gear 2.30
3rd Gear 2.06 3rd Gear 1.71
4th Gear 1.55 4th Gear 1.41
5th Gear 1.27 5th Gear 1.18
6th Gear 1.10 6th Gear 1.00
7th Gear 1.00 7th Gear N/A

 

[FLTR2008TRIKE]

So I guess the answer is "No, no one has any experience with that transmission" ? It would be nice to see a comparison of gear ratios in the Baker vs Harley

Beyond what has been stated with first gear being a lower ratio for less clutch slipping to take off and 7th having the same ratio as 6th gear. The DD7 gear ratio are closer and the gears are cut slightly different than stock. This gives the rider a smoother shift that has a click to it instead of a clunk.

Add in the Baker billet street door with wider bearings to reduce mainshaft flexing under heavy torque load.

Most builders will agree that having a 7 speed isn't needed. Money would better spent on just the Street door and changing your primary drive or final drive ratio if you need more grunt in the lower gear range.

The clunk isn't hurting anything. Just how the transmission is built.

 

[micbear]

Thanks 08 Trike,
thats the kind of input, I was looking for and duly noted, I will put it to rest now! ThumbUp
micbear

 

[FLTR2008TRIKE]

There was a discussion a couple of years ago about HD 6 speed cruise drive on another forum.

The clunk come from the heavy mass of gears rotating and the differences in the ratio. There was 2 things that were discussed about shifting the 6 speed. Changing the leverage of the shift rod by drilling a mounting hole 1" lower on the front arm the shifter pegs are attached to.

This relocation was reported to give better shifter throw by reducing the arm travel.

The second was clutch adjustment. Having good clutch plate seperation when your using the clutch. This would help slow the rotating mass in the transmission to lessen the clunk.

Tom

 

[DK Custom Products]

My only is experience is that a friend of mine installed the DD7 in his Ultra a few years back.

Rode with it for 2 seasons and never used first (too low). He removed it and sold it after the 2nd year.

I would not spend the money on one...BUT, if I had one, I would consider changing out the 30 tooth front pulley for the 32. With the granny 1st gear I don't think I would have a problem with 1st anymore with the taller gearing, and I would have the option of cruising with the taller gearing in 7th. My current 6th is not a problem, but when cruising at 80 mph+ it might be nice to have the RPM's a bit lower.

 

[HarleyPap57]

I've been looking at the DD7 Transmission before I bought my trike for my '07' Ultra. Now I'm thinking about getting it for my '14' TG because I don't like riding around at 3,000+ RPM all the time. I ride both back roads and interstate and going to and from work I usually ride between 70 and 75 which puts my over 3,000 and it's hurting my gas mileage. Thinking about the DD7 and changing my front drive sproket from the 30 tooth (or what ever it is) to a 32 or 34 tooth. The low first gear will also help when pulling a trailer.

 

[msocko3]

I've been looking at the DD7 Transmission before I bought my trike for my '07' Ultra. Now I'm thinking about getting it for my '14' TG because I don't like riding around at 3,000+ RPM all the time. I ride both back roads and interstate and going to and from work I usually ride between 70 and 75 which puts my over 3,000 and it's hurting my gas mileage. Thinking about the DD7 and changing my front drive sproket from the 30 tooth (or what ever it is) to a 32 or 34 tooth. The low first gear will also help when pulling a trailer.

If any return on fuel mileage is realized it will never pay for it self, as for the engine turning 3,000 rpm, that's the sweet spot for the Twin Cam. When I had my 2010 Triglide I switched from the stock 32 tooth sprocket to the 30 tooth. The switch raised my RPM's up which made 6th gear actually usable at 70 mph vs 75 mph and above, the fuel mileage didn't change a bit. The reason your getting crummy gas mileage at 70 - 75 mph is your engine is trying to push that barn door of a trike through the air, the mileage is going to take a hit no matter what you do.

IMO a Twin cam running 3,000 - 3,500 rpm is music to my ears, not to mention when you twist the throttle you get instant response. Drop the rpm's out of the sweet spot and it will be more lethargic when you twist the throttle unless you either down shift, or swap the cams out for a set that makes torque at a lower rpm than stock cams.

 

[geezerglide11441]

If any return on fuel mileage is realized it will never pay for it self, as for the engine turning 3,000 rpm, that's the sweet spot for the Twin Cam. When I had my 2010 Triglide I switched from the stock 32 tooth sprocket to the 30 tooth. The switch raised my RPM's up which made 6th gear actually usable at 70 mph vs 75 mph and above, the fuel mileage didn't change a bit. The reason your getting crummy gas mileage at 70 - 75 mph is your engine is trying to push that barn door of a trike through the air, the mileage is going to take a hit no matter what you do.

IMO a Twin cam running 3,000 - 3,500 rpm is music to my ears, not to mention when you twist the throttle you get instant response. Drop the rpm's out of the sweet spot and it will be more lethargic when you twist the throttle unless you either down shift, or swap the cams out for a set that makes torque at a lower rpm than stock cams.

:Agree: 100 percent regarding the Twin Cam "Sweet Spot" being 3,000 to 3,500!! That is where I normally run in Cruise and where I normally shift gears!!

Roger

 

[dirtdobber]

Hd SE 6th gear is 0.885 as where the DD7 is 1.00

I like baker transmissions. I usually have custom gearing done for the application.
Geared too low on a trike, I think I would like that when loaded and 2 up or pulling a trailer.

I have always felt that the HD transmissions were geared too tall in the first 3 gears.
My engine builder does specials on the Baker transmission at times.
Special price with installation.
It reminds me of the gearing on a goldwing trike except there is a 6th and 7th gear added.

 

[Sloufoot]

Just my opinion, but the engineering that has gone into the Baker trans is far superior to what Harley puts out. That being said to change from stock to one of the Baker trans is a bit too expensive. Unless you are having to change the trans anyway. Now if you are in heavy traffic or a parade all the time that first gear would be a plus.
I think the best option now would be to go to the new cams that are real stump pullers at a low low RPM. The close gearing would be nice also, but now with the new cams you have big torque at a very wide range of RPM. Not as narrow as they used to be.
The one big thing that Baker makes is a shift barrel that puts neutral where 1st gear is stock. That would take the neutral finding thing away.
But again,,, JMHO ...!

 

[rhino 2]

Just wondering.. Does the 7 gear have a gear indicator??
Without it at highway speeds you will be trying to upshift into 8Th...

 

[msocko3]

Just wondering.. Does the 7 gear have a gear indicator??
Without it at highway speeds you will be trying to upshift into 8Th...

Only if you have a Power Vison, TTS or wire in the supplied speedometer correction device. There may even be a chance cruise control won't work without one of these devices to make the correction.

IMO, the 2011 and later Triglides with the 30 tooth transmission sprocket, get moving pretty good. A deeper 1st gear would only come in handy if your pulling a heavy load. Baker does makes some nice products.

 

[dirtdobber]

better TQ does help a lot but there is no substitute for gearing.
My Mystery trike has a 113 ci, 124 hp, with over 140TQ. Th engine pulls it just fine but the lowered 3 gears is what made it happen. I am using a DD6 with custom gearing. The biggest advantage with the TQ/HP is I don't have to gear down much. Even pulling the trailer loaded it is good at start off up hill from a red light. It's like it Isn't there.
Every body has their own thoughts. It is a ex drag bike.