120R mileage and reliability
Road Captain
Joined: Aug 2008
Posts: 501
Likes: 2
From: Downtown Chicago
4K on mine (crate not kit), no issues at all. mpg? no idea, dont care, north of 35, fill up every 160 on the trip OD (old habit from the V Rod with a gauge you cant trust). Would do it again in a heartbeat. top end loud? a little, but with the proper exhaust for the engine (D&D Borezilla) the top end tick goes away.Going fast, whenever you want, never stops being fun!!!
Road Captain
Joined: Oct 2007
Posts: 721
Likes: 0
From: Texas
4K on mine (crate not kit), no issues at all. mpg? no idea, dont care, north of 35, fill up every 160 on the trip OD (old habit from the V Rod with a gauge you cant trust). Would do it again in a heartbeat. top end loud? a little, but with the proper exhaust for the engine (D&D Borezilla) the top end tick goes away.Going fast, whenever you want, never stops being fun!!!
Dittos on the GOING FAST, WHENEVER YOU WANT!!!! Rode from Houston to Sturgis last month, had a blast!! Got more MPG than anyone else in our group, and we weren't lolly gagging, we were never passed by anyone, except low flying aircraft!!
Have over 5K miles on her, not a problem!!
Road Captain
Joined: Aug 2008
Posts: 501
Likes: 2
From: Downtown Chicago
I my modded mine before install, dont believe there is much to gain from doing much to this motor. Did cams (Tman 662-1), Roller rockers (S&S) HPI TB manifold (stock front) and headwork by WFO Larry. Still running strong (took 3rd in a dyno shoot out a couple of weeks ago vs some big S&S motors) TQ/HP right where it was from when I picked it up this spring. I think history of builds will show, there is not that much left in the crate unless you want to up the compression, put the hurricane heads on etc.
cant even imagine what a stocker would feel like anymore.
cant even imagine what a stocker would feel like anymore.
Road Master
Joined: Mar 2008
Posts: 1,209
Likes: 5
From: Michigan
I think your right Eric, anything you did to this motor to make a noticeable increase in HP/TQ would make the motor unstreetable, meaning you could not run pump gas in it. Although a procharger would make a nice xmas gift. I rode a stock bike a few weeks back and it was pathetic. Its amazing how you get used to the power of the 120 and loose touch with the reality of the stock set up. 9200 miles and still havin a blast.
Road Captain
Joined: Oct 2007
Posts: 721
Likes: 0
From: Texas
My thoughts exactly, except I only have 5500 miles, and is a blast every time I ride!
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Advanced
Joined: Jun 2011
Posts: 72
Likes: 0
From: Indiana
Hello to all. I ran across this thread while searching for other 120R owners. I've got an 08 Fat Bob with a 120R (kit motor) and just hit 6,000 miles on the motor.
My motor recently started make some strange sound and when I took it to the dealer that did the motor the tech thought it might be a lifter issue. Well yesterday they started tearing into it and found that the bolt fastening the large chain sprocket had snapped off. The noise was from the head of the bolt banging around against the cover.
The bolt that I circled in read is what broke off.
Can anyone explain to me how or why this happened? Does anyone have an educated guess? I asked the tech at the dealer and he said he'd never seen anything like it. I'm not a gearhead at all. I have zilch in the way of mechanical aptitude. I am just wondering if it was something that I did that caused the problem or if there was something I could have done to prevent it from happening.
Any help or suggestions will be greatly appreciated.
My motor recently started make some strange sound and when I took it to the dealer that did the motor the tech thought it might be a lifter issue. Well yesterday they started tearing into it and found that the bolt fastening the large chain sprocket had snapped off. The noise was from the head of the bolt banging around against the cover.
The bolt that I circled in read is what broke off.
Can anyone explain to me how or why this happened? Does anyone have an educated guess? I asked the tech at the dealer and he said he'd never seen anything like it. I'm not a gearhead at all. I have zilch in the way of mechanical aptitude. I am just wondering if it was something that I did that caused the problem or if there was something I could have done to prevent it from happening.
Any help or suggestions will be greatly appreciated.
Outstanding HDF Member
Joined: Dec 2008
Posts: 2,182
Likes: 0
From: Phoenix
Which bike would that be? The biggest bike I see on there is 445hp 376cuin engine (http://www.bosshoss.com/view_bike.asp?x=BHC3LS3SS), which is a bored out 350. The 350 isn't a big block motor, it's a small block motor (http://en.wikipedia.org/wiki/GM_Small-Block_engine).