You're more than welcome, that's what these forums are for. I built a 120 a few years ago for my 06 Ultra Classic which is still 2 wheels. It turned out well, it's a hoot to ride.
H-D 120R Engine - New or not?
- Thread starter GoSlo
- Start date
You're more than welcome, that's what these forums are for. I built a 120 a few years ago for my 06 Ultra Classic which is still 2 wheels. It turned out well, it's a hoot to ride.
120ST First Ride Report
Today I was able to finally pick up my trike from the shop from having the 120ST engine installed. After that I got in a 175 mile trip before the rains started. I got in some freeway miles, but mostly climbing up a winding road to a winter ski resort area (Stevens Pass) at 4,100 feet. My first impressions were "Ahhh", and "Wow". Before I got to the shop, the tech told me on the phone that it was in his opinion; "smoother and with longer legs", and maybe less low end grunt than the 113 with 255 cams. He is right, the power doesn't seem to give an instant hint of the displacement - until you twist the throttle just a little, and then it is solidly there.
It's still a trike, and not a crotch rocket for sure, but going up that elevation in 6th at 70 mph seemed like child's play. I was hitting it pretty hard to make sure everything was right, and then coming back I had to get gas way before I thought I should have to. A real good thing I was going downhill, my gas light was on forever and took 4.7 gallons to fill. Riding hard and fast uphill got me 25 mph, but what fun it was!
I also have to say how pleased I am with how the Harley shop treated me through all of this. My bike has 48,500 miles on the odo so I had them do the 50k service while there. They found several things including 2 completely broken fairing mounts, the larger ones, and they replaced them for free. Also, my radio was cutting out sometimes so they installed a new takeoff, free as well including no charge for diagnosis and shop time. This was all in addition to just cost on the engine and no installation fees.
They used a dyno map from a previous 120ST 2 wheel tune, and then tweaked it a little with the Power Vision. That bike had 115 hp and 123 torque. It was also a pretty cool day today, about 66* or so. The 113 ran really hot and kicked on the fans right away every ride. The 120 never kicked on the fans until I stopped after all those miles. Not sure how much of that is the cooler weather, but the 120 seemed to run a lot cooler to me, about 180* most of the time on the dashboard guage. I had them leave off the running boards this time, that may contribute to it being cooler too.
I am hoping for no rain tomorrow so I can ride again. With all of the shop time I have had this year my riding time has been minimal. This time (#3) my trike was there from 8/11 to 9/19. Oh well, I'll make the best of it and start planning for next year too. Stupid Washington rain! (said after the dry-est summer ever...)
I am real happy with how it turned out, it just feels completely right now, and what I should have done first.
Today I was able to finally pick up my trike from the shop from having the 120ST engine installed. After that I got in a 175 mile trip before the rains started. I got in some freeway miles, but mostly climbing up a winding road to a winter ski resort area (Stevens Pass) at 4,100 feet. My first impressions were "Ahhh", and "Wow". Before I got to the shop, the tech told me on the phone that it was in his opinion; "smoother and with longer legs", and maybe less low end grunt than the 113 with 255 cams. He is right, the power doesn't seem to give an instant hint of the displacement - until you twist the throttle just a little, and then it is solidly there.
It's still a trike, and not a crotch rocket for sure, but going up that elevation in 6th at 70 mph seemed like child's play. I was hitting it pretty hard to make sure everything was right, and then coming back I had to get gas way before I thought I should have to. A real good thing I was going downhill, my gas light was on forever and took 4.7 gallons to fill. Riding hard and fast uphill got me 25 mph, but what fun it was!
I also have to say how pleased I am with how the Harley shop treated me through all of this. My bike has 48,500 miles on the odo so I had them do the 50k service while there. They found several things including 2 completely broken fairing mounts, the larger ones, and they replaced them for free. Also, my radio was cutting out sometimes so they installed a new takeoff, free as well including no charge for diagnosis and shop time. This was all in addition to just cost on the engine and no installation fees.
They used a dyno map from a previous 120ST 2 wheel tune, and then tweaked it a little with the Power Vision. That bike had 115 hp and 123 torque. It was also a pretty cool day today, about 66* or so. The 113 ran really hot and kicked on the fans right away every ride. The 120 never kicked on the fans until I stopped after all those miles. Not sure how much of that is the cooler weather, but the 120 seemed to run a lot cooler to me, about 180* most of the time on the dashboard guage. I had them leave off the running boards this time, that may contribute to it being cooler too.
I am hoping for no rain tomorrow so I can ride again. With all of the shop time I have had this year my riding time has been minimal. This time (#3) my trike was there from 8/11 to 9/19. Oh well, I'll make the best of it and start planning for next year too. Stupid Washington rain! (said after the dry-est summer ever...)
I am real happy with how it turned out, it just feels completely right now, and what I should have done first.
If you want a little more grunt for take off or quicker response at lower rpms you can make a change in one of 3 places
Lower the front pulley tooth count such as going from a 32 to a 31 or even to a 30 tooth. ( which would require a belt change)
Second option is to raise the tooth count on the clutch basket from a 46 tooth to a 49 tooth count.
Third option is to swap your cruise drive 6 speed and install a Baker 7 speed. The lower first gear will give you more grunt taking off.
Welcome to the big engine club
Lower the front pulley tooth count such as going from a 32 to a 31 or even to a 30 tooth. ( which would require a belt change)
Second option is to raise the tooth count on the clutch basket from a 46 tooth to a 49 tooth count.
Third option is to swap your cruise drive 6 speed and install a Baker 7 speed. The lower first gear will give you more grunt taking off.
Welcome to the big engine club
If you want a little more grunt for take off or quicker response at lower rpms you can make a change in one of 3 places
Lower the front pulley tooth count such as going from a 32 to a 31 or even to a 30 tooth. ( which would require a belt change)
Second option is to raise the tooth count on the clutch basket from a 46 tooth to a 49 tooth count.
Third option is to swap your cruise drive 6 speed and install a Baker 7 speed. The lower first gear will give you more grunt taking off.
Welcome to the big engine club
I've already done the 32 to 30 swap so I think I'm done with the mods now. I have not even revved it past about 3,300 yet - so I think there is a lot more to be tapped if I needed it. And now - it's raining again...
3rdwheel, I'm sure glade to see someone on here with the H-D 120ST engine, I've been curious about the behavior of the 120ST with the SE-259E cam. I have the 120R in my '09 triglide, which I'm still getting use to, only have a little over 3000 miles on it. I did change the cam with a custom cut cam (I'm told the cam is close to a SE258), the 120R is a happy engine at around 3000 rpm, and at this time with my last fill up of gas was 35.1 mpg. I would say that my torque comes in at about 2300 rpm's. I'm very interested in hearing more about your new engine has you get more time with it.
Butch
Butch
I also want to follow your experiences with that motor. I keep trying to blow mine up so I can stick in either the 120 ST or an S&S. Keep us up to date please!!!
Trent, you might want to just start planning on the upgrade now because I bet they catch on and sell rapidly. You won't be disappointed.
This morning I rode into work via the longest route I could think of, and it was all I could do to actually park it. I really like how the 120 runs and there are no flat spots in the entire range of riding I do - including low rpm roll-on's. Maybe you've experienced occasional "bucking" if your rpm's were too low for your situation and after you gave it throttle, you had to downshift? Not so with this one. The low end 1,800 rpm's and up just have enough torque and flywheel and it is tuned well enough so it can handle it. (Don't worry - I don't ride in that range). I even started out in second gear by mistake without much effort or clutch. It really makes riding fun because it is peppy, yet tame as well. It feels like a good sports car that can set the pace, or just cruise all day at whatever speed you'd like. At 70 mph with the 30 tooth sprocket the rpm's are 3,000. It sounds real good too especially coming onto the freeway getting up to speed and yet not overbearing while cruising. But, when you want to live dangerously it's all there. I have a lot of roundabouts in my commute, and coming out of them I can really "light them up" if I want - and I do!
Next time I am in Meridian, I'll let you ride it if you want. My Dad still lives there so I am back occasionally. I think it is the perfect engine for trikes and a real winner for Harley.
Oh I am planning on it alright. 
Gotta blow mine up first though!!. Sounds like it runs similar to mine. My dealer has no trike dyno either.. The map they used was an Ultra that a Bud of mine did the identical stage 4 on that I did, and his dyno'ed at 114 hp,, then they tweaked it. Course we lose a lotta that HP thru the mechanics of a Trike. But still has puuhlenty of ballz!! Would love to take a spin on yours and that is very nice of you to offer.. Promise I will be careful!!ThumbUp
Let me know if you head this way and maybe we can set up ride.. Would look forward to that! Thnx!!!
Gotta blow mine up first though!!. Sounds like it runs similar to mine. My dealer has no trike dyno either.. The map they used was an Ultra that a Bud of mine did the identical stage 4 on that I did, and his dyno'ed at 114 hp,, then they tweaked it. Course we lose a lotta that HP thru the mechanics of a Trike. But still has puuhlenty of ballz!! Would love to take a spin on yours and that is very nice of you to offer.. Promise I will be careful!!ThumbUpLet me know if you head this way and maybe we can set up ride.. Would look forward to that! Thnx!!!
3rdwheel; your 120SE is excellent news as I previously wrote on this threadand “where to Dyno a Trike” is getting my attention.
LastThursday I took my 2011 Tri-Glide to the Woodstock, Il. H-D for a DynoJet test. This is the test results:
MaxPower=76.84 at Engine RPM=4.59 and Max Torque=96.15 at Engine RPM=3.8
We discussed an engine build this winter from current 103 to a 110. But after all the information I have been gathering on this site I might change my thinking. I had discussed the 120SE but was concerned with higher heat when bogged down in town summer traffic. Not to mention lowering my fuel millage lower than the current 25 MPG. But I have been really disappointed in the lack of power and performance the last two years riding out west in the mountains.
Hopefullyyour cold/rainy weather doesn’t slow down your riding and keeping us updated.Thanks DJ
LastThursday I took my 2011 Tri-Glide to the Woodstock, Il. H-D for a DynoJet test. This is the test results:
MaxPower=76.84 at Engine RPM=4.59 and Max Torque=96.15 at Engine RPM=3.8
We discussed an engine build this winter from current 103 to a 110. But after all the information I have been gathering on this site I might change my thinking. I had discussed the 120SE but was concerned with higher heat when bogged down in town summer traffic. Not to mention lowering my fuel millage lower than the current 25 MPG. But I have been really disappointed in the lack of power and performance the last two years riding out west in the mountains.
Hopefullyyour cold/rainy weather doesn’t slow down your riding and keeping us updated.Thanks DJ
55IL, I was in the same boat as you except I did have a 113 built with the best HD heads, welded crankshaft, and all the best options they recommended. Maybe it's my bad luck, but both cylinder base gaskets leaked at separate times, then the wrist pins came loose, and that engine is still in a box at Harley waiting for new parts and to be put together again. When it did run, and it ran pretty good, it wasn't dynoed despite my best efforts and it felt lacking.
So, I opted for the 120ST, and couldn't be more happy.
I did another 100 miles after work today and by Thursday I'll have the 500 mile oil change done.
All that to say, a build may not be the best answer. I totally wish I had done this first instead. I think this factory built engine is flawless, and it has a 1 year warranty. I do wonder about the heat in summer too, but I don't think it will be worse than a 103.
When it is right like it feels now, it is so much more fun.
3rdwheel; Stopped at a different H-D shop to have them quotea 120ST motor install and any other requirements. They quoted the engine, heavy duty clutchspring, SE super tuner, SE air cleaner, gaskets and labor. This way when and where I decide to have thiswork done I would have price comparison.
However, the discussion of changing out my clutch assemblyfor the SE variable pressure clutch and new big twin compensator may berequired. If this IS required I’mnot sure if I will be able to pull the clutch in especially town traffic and I’mnot getting any younger. J Did you need this?
Well hope you had a nice weekend to put some good miles onyour new build….. looking forward to any updates. DJ<o
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Are any of the installers advising to go to a larger exhaust header with the 120 motor?
Gorilla; No, their was no mention and I didn't even think of asking. They said I would have to replace my present SE air filter due to the increased intake port. Neither dealer I have visited had a 128SE engine in stock.
In the 2016 SE catalog does mention "We recommend combining this engine with your choice of SE 58mm High-Flow Air Cleaner and the SE High Flow Exhaust system." But I figured the catalog recommendation is a sales ploy. Of course it would only make sense the exhaust port would increase, I have no idea, but the H-D service/engine builder should have caught this, right? Thanks, DJ
3rdwheel; Stopped at a different H-D shop to have them quotea 120ST motor install and any other requirements. They quoted the engine, heavy duty clutchspring, SE super tuner, SE air cleaner, gaskets and labor. This way when and where I decide to have thiswork done I would have price comparison.
However, the discussion of changing out my clutch assemblyfor the SE variable pressure clutch and new big twin compensator may berequired. If this IS required I’mnot sure if I will be able to pull the clutch in especially town traffic and I’mnot getting any younger. J Did you need this?
Well hope you had a nice weekend to put some good miles onyour new build….. looking forward to any updates. DJ<o
A few thoughts, yes you'll need a different air filter setup due to the larger throttle body size. The one you have now is 50mm and the air filter backing plate is meant for that one. The throttle body for the 120st will be 58mm. What air filter setup do you presently have? Might be able to save some money with just a simple backing plate change vs the who thing.
Exhaust, what exhaust do you presently have, head pipe and mufflers?
Clutch, stock may not handle it very well. You could go to a Barnett extra plate topped with a Evolution 480lb spring and a Clutch Wiz. You can get the spring and the Clutch Wiz from http://www.tglidestuff.com/. The web site for the Clutch Wiz is here http://clutchwiz.com/.
Compensator, your Triglide already comes with the big twin compensator. The only way you would need a new one is if your present one is bad.
3rdwheel; Stopped at a different H-D shop to have them quotea 120ST motor install and any other requirements. They quoted the engine, heavy duty clutchspring, SE super tuner, SE air cleaner, gaskets and labor. This way when and where I decide to have thiswork done I would have price comparison.
However, the discussion of changing out my clutch assemblyfor the SE variable pressure clutch and new big twin compensator may berequired. If this IS required I’mnot sure if I will be able to pull the clutch in especially town traffic and I’mnot getting any younger. J Did you need this?
Well hope you had a nice weekend to put some good miles onyour new build….. looking forward to any updates. DJ<o
I find that my clutch pull is really easy with those upgrades, maybe more so than stock even. I did notice that right away after it was changed and not only is it easy, it is also real smooth engaging the gearing - no more "clunk".
Since my trike is a 2007 they had to order an HPI 55/58 throttle body that was made for a throttle cable, not FBW like the newer ones. Mine could not use the TB that came with the 120.
Now for the good news. Over the last 9 days I've put on 1,000+ miles and I've had the first oil change. There was no concern about shavings in the oil and now I'm good to go until the next regular service interval. I am using Syn3 at their recommendation. Each time I ride it I am so impressed with the feel of it. It feels very strong and I can't say "it really comes on strong at x,xxx rpms", because it is just always ready for more. As much throttle as I can give it, or even lugging it a little, it just goes. It doesn't lurch or pop on deceleration or act boggy. Until yesterday I had not revved it much but coming onto the freeway I took each gear to 5,000. It not only sounded like a well tuned muscle car, it really got up to speed (and then some), very quickly!
In 60-70* weather and riding solo with the oil cooler, the Power Vision shows the engine temp consistently at 225*. The Wards Fans only come on when I come to a stop after I've have shut the engine off.
I have Vance & Hines true dual headers with FuelMoto E-Series slip ons.
It took me a while to get here after having done different gearing, different motors and cams, reverse gearing replacement, and other stuff. The journey and cost and frustration was worth it. It is now what I expected it to be. You get so much money into these trikes you HAVE to make them work right. And now everything finally works right and all at the same time!
Oh yeah, the bad news...I haven't yet gotten better than 25 mpg but that's a price I'll gladly pay. Doesn't matter if I ride hard or soft; it's 25 mpg.
When I had the oil changed the other day, one of the techs asked me if I had clocked in yet since I am there so often. That's finally going to change I hope!
3rdwheel;[SIZE=3 said:
3rdwheel; Thanks so much for the feed back. It is so important to me as I wasn't going to spend this much money (at my age) with out more information. I'm hoping to get a couple more traveling bucket lists under my belt before I go under.
Question, are the exhaust headers on the 120ST the same size a the 103? Regarding "Wards Fans", is this something that is required?
I'm getting 25mpg currently but its the price I will gladly pay. I understand that you didn't have to change clutches just upgraded SE clutch spring, Thanks DJ
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Exhaust headers are the same size as the 103 is. Wards Fans are just an option I chose for more cooling, not required at all. I wanted to keep as much heat off of my wife's legs as much as possible.
3rdwheel, I have a very similar application as the 120st - totally re-built 120r with a cam change similar to the SE 259E and I am getting in the vicinity of 36 mpg two up with the wife!! I too have the HPI 55/58 TB and the PV with the Target Tune module (TT). I have not run across anyone in my area with a 120st installed so I do not have any first hand knowledge regarding an acceptable fuel mileage figure, but I certainly would not be happy with the mileage you are experiencing.
I Know I am not running lean either, as my set AFR cruise range is set at 14.2:1 and all other areas in the table are much richer than that. I am quite sure the TT installation where I am running the Wide Band O2 sensors in a closed loop configuration is a great help as well.
Although the motor is most certainly not broken in as yet, I would be looking for some reason you are in the mid 20's with your fuel mileage.
Mine is extremely strong as well and will lift the front wheel in 3 gears if I so choose, which I do not since I am the one to pay for breakage!!
In any event, enjoy the Trike as you will really grow to love the torque/hp with that motor.
Roger
H-D 120ST and Bakers DD7 Drive train upgrade?
Has anyone installed the Bakers DD7 Drive train upgrade in their trike?
This winter I'm thinking seriously of upgrading my tri-Glide 103 to the new 120ST engine. Any thoughts if a Bakers DD7 upgrade at the same time?
My thinking is a lower gear off the line (not to hot rod) for easer roll-up transition and taller drive gear, any thoughts? Thanks DJ
Has anyone installed the Bakers DD7 Drive train upgrade in their trike?
This winter I'm thinking seriously of upgrading my tri-Glide 103 to the new 120ST engine. Any thoughts if a Bakers DD7 upgrade at the same time?
My thinking is a lower gear off the line (not to hot rod) for easer roll-up transition and taller drive gear, any thoughts? Thanks DJ
My apologies, I new my writing skills would be a problem but I will try to do better. Thanks DJ
My thoughts, I kind of lost my way
.- - - Updated - - -
I can't speak to the DD7, IMO I would save some money and just ride it with the 120ST. I think it will come off the line pretty snappy on its own. Get too much torque hit on the bottom and you'll find the next weakest link.
3rdwheel; Point well taken and I agree. I will keep you posted when things at my end begin to happen. Again thanks for your feedback, DJ
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