So the time may have come for an engine replacement. Big Bird has 160,000 miles, runs great, uses no oil BUT, the four screws that attach the stator have broken off in the crankcase. They are hardened steel and the case is aluminum so, they can’t be drilled. We’ve tried. They could be dissolved with electrolysis but that would require removing the engine and splitting the cases. I’m not doing that on a 160,000 mile engine.
So, the question is, 120R or 103? The 120R is a complete engine sans fuel injection (and warranty). Or the 103 long block. The 103 does not come with cams, rocker boxes, cam cover or fuel injection although I may be able to use mine. Also, the 103 has a year warranty.
I am really interested in those of you that have a 120R and what kind of reliability you’ve experienced.
PS. A 120ST is not an option.

 

I can't comment on the 120 or the 103, and I'll probably get flamed for this, but when my 107 fuelmoto kit broke a valve spring and the engine basically destroyed itself at around 25K miles on the kit, I decided on a S&S 124 LC. This was put in earlier in 2020 and I have around 3K miles on since the install (would have been more if we didn't have all the restrictions based on covid). The bike is a 2013 Ultra Limited. I also had the transmission beefed up, and had a Baker compensator put in, and upgraded to a Barnett Scorpion clutch put in to handle the extra performance.
This engine has plenty of power, sounds wonderful, gets around 35mpg around town and 43mpg on a 500 mile ride over the passes in WA state. Who knows how it will hold up over time, but my indy swears by it and so far I'm nothing but pleased.
Hope that helps.

 

Funny, a few years ago a FM-installed FM107 kit on my 2013 FLTRU broke a valve spring, they said first they'd seen such a thing. Maybe you were the 2nd. In my case just a bent valve and of course new valve spring.

 

What cam were you guys using in your 107's?

 

My 2009 softail with the FM 107 kit broke a valve spring as well a few years back. Mine must have been the third. Dennis

 

woods 777

 

I would contact a couple engine rebuilder to see what they think can be done with the bolts. Next I would look for a cheap block and have it rebuild or put it in and run it. 1500 to 2500 can be found for a used engine. Another is to contact fuel moto about their 124 Finding a used engine if you can install will be around 2500. Getting your engine redone is going to be 4000 on up. The 120 I would be worried about the crank for all power. The long block is a nice option but by the time the bike is on the road you could get another 2000 in it
All the money your putting into your pride and joy it might be time to look at a replacement. By the miles you have on your bike you enjoy riding. Maybe time to look at the m8 lineup. Good luck

 

My Bro did a S&S 124LC in his 2016 RGS and it's pretty insane and dependable as hell.

IF I were in your boots, I would seriously consider going the S&S route instead of the 103" or 120R route.

YB

 

I put a 120R in my bike...back on the first of February of this year. Only has about 8000 miles on the engine, so I can't really speak on longevity, but it sure is a lot of fun.

 

That quite a few miles on that motor. Glad it’s working out for you.