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120R or 103 Stage IV?

21K views 38 replies 21 participants last post by  tharrah88 
#1 ·
It's getting down to decision time.

I am either going to go with the 103 Stage IV or the 120R.

The way I figure it, cost ways it's pretty much a wash.
The cost for either would be about the same considering I would probably have to pay for labor to have the Stage IV kit installed.
I could do the swap for the 120R and then have my old engine to sell.
The 120R already has the lefty bearing too.

Thoughts?
 
#7 ·
It´s already a 103. We did that before I even rode it away from the dealer.
I have just kind of outgrown the basically stock 103.
I am getting ready to pull the trigger on the 120R.:nod
I really think that a mild 120R will be more dependable than a 103 Stage IV.

Then the bike will be ¨done¨. (At least that´s what my wife thinks.):laugh
 
#8 ·
There will be a few more items you'll need to compliment the 120R. Throttle body, SE comp sprocket, SE clutch spring etc. Maybe even a frame stabilizer kit to keep everything straight when pulling the trigger on that big incher !
 
#11 ·
Got em on the list! Also the automatic compression releases.
Anybody know if the newer heads will accept the manuals?
 
#12 ·
Can't speak of how the 103 build would do, imagine quite well, but I went with the 120JIMS from 95" and can tell you there is a world of difference power wise(bike is '05 DynaSuperGlideCustom.) Long list of things done on the bike with the 120 including those listed by Schmidtys. Did not go with stabilizer and so far seems OK in the handling department, but I should point out that I rarely "get on it" so stabilizer may be needed if riding hard. Be it HD 120R or JIMS, they take you to a whole new level of performance and probably way more than I should have available in my right hand. Don't ride much in the city, stop and go, but head for the mountain roads here in WV and Interstate and performance in 3rd, 4th, and 5th gear is outstanding. "the thing" just never seems to want to quit pulling in 5th gear and can get you in trouble with the "boys in blue" if not careful. As for the compression releases, mine are manual and kind of a pain for those things are definitely hot to the touch. Switched to full finger gloves instad of the fingerless ones. A negative view on such power is that the bike I ride is not a "sport bike" and have to caution myself to not ride it as such, but if power is what you want, a 120 will definitely deliver and most likely would exceed the speed factor of the tires??
 
#16 ·
I'm fixing to find out.
In the final stages of finishing up my parts list.:drool
 
#19 ·
Three guesses what´s in the back of my pick-em-up truck.:know
 
#22 ·
Update: I picked it up in Temple, Tx.
Didn´t get the timing right to meet up with Roy as I got called back here to work.:cussing
All I have to do is install it now.
Going to be a while though. I´m off to Africa Tuesday AM.:mad

I will probably start a different post when we do the install.:nod
 
#23 ·
Best of luck on that install. Can't wait for the youtube video.

Sorry we didn't get to meet up. It'll make for a nice ride to show it off up here around DFW.

Just got back from Germany last night and heading to NY on Wed.
 
#24 ·
Hah! Haven´t even started on the install and I want to change some parts around. That new variable pressure clutch that HD came out with might be just the thing to replace the race clutch.:think

Sounds like my travel schedule Roy.
Tomorrow, Houston and Atlanta.
Wednesday: Paris
Thursday: Africa

Them there jet-setters got nothing on us.:laugh
 
#25 ·
Hey Vettster, if you do the 120R, you will not regret it ! Just finnished my swap from a 103. Its like the difference between a scooter and a freight train !! Besides having much more hp & tq, it also runs just like a stock motor should. No heat issues if tuned properly. Good luck and safe ride, Wade.
 
#27 ·
Bumwad,
Didn't go with the HD 120R, but JIMS 120 and from what I am told you end up with some 125hp at the rear wheel w/ either one and no question, you will definitely feel it in the only true dyno, your rear "buttocks." Noticed your location and just recently came back from Ottawa area and must say the gas rated at 91octane just did not work very well in my bike, valve clatter, etc. Added some boost fluid to it each time which I had brought with me and helped, but what's the deal up there with the gas?? Perhaps I just got a bad batch, but three separate times and not good either time. Just curious??
 
#28 ·
Instructor, Not sure about your problems with our fuel, but i have noticed an increase in valvetrain noise over the stock 103. Could this be the "valve clatter" you mentioned ? I usually run 91 octane in my bike and dont notice a big difference running the higher grade. Not sure of the specs on your 120, maybe your comp ratio is higher?
 
#29 ·
Getting back on topic. Here is a couple of teaser photos of the 120R.:drool
 

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#30 ·
There was a sweet SG with a 120R @ RawHide HD, custom wheels and apes, and many other mods. Before I could get there to take a look at it, it was sold. Damn, for 26k I thought that was a decent deal! Good luck with the 120R definatley can't wait to see one of those on the road!
 
#31 ·
The 120R will cost U another grand or so for intake stuff and there is more than that, like your computer programs need attention so a tuner is in order, it (SE Tuner) comes with the Street Stage IV as does the 58mm throttle body, bigger injectors and pistons, rings, barrels, CNC sleeper heads, clutch spring and some other odds and ends... U should be able to get a price on the labor and get a real quote for ALL the stuff that U will need just to get it up and running. U can sell all the parts U remove for the stage IV for a grand, remember, heads, throttle body are worth alot for porting/polishing and boring for future builds.
I actually went through the numbers and it was between $1200 and $2000 depending on the way I went with parts for the 120R and the amount of labor I was willing to do myself on the Stage IV kit.
There are a couple of different kits, and I went with the Race Stage IV vs the Street Stage IV. More stuff with the Race version and I think more cost as well.
The 103 I have is faster than the CVO 110 RG's. Now spend money and that 110 will jump better.
If I had more than the 23K miles on the bike, say 75K, I might look harder at the 120R and do a motor change, if, I still loved the bike like I do now!
 
#32 · (Edited)
Pete: I ran the numbers and with selling my "old" engine they were pretty close.
I have it sold for 3k so that cuts the cost to almost half with me doing the labor.
I figured that my mechanical abilities are better suited for a swap than they are for opening up a perfectly good engine.
Anyway, not much progress to date on the project. I got sent back to Africa. Meanwhile, the 120r is being utilized for a coffee table in my den.:eek
 

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#33 ·
We recently sent a 2010 FLHX/120R back home to Rhode Island.
Our heads, 66mm S&S Throttle Hog, Wood 9F cams, Borezilla.
Hits like a freight train to the point that on throttle snaps only, w/o fanning the clutch lever, it has the f/tire waaaaaaaaaaay up.
144 hp/140 ft/lbs, SAE, striking big torque VERY quickly, and carries it out the back door.
Scott
 
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