Considering putting a Jims 131ci SE motor into a 2009 Road King. Have not been able to find any reviews that have really addressed the questions I have. Does anyone have any idea on the dependability and reliability of this motor. Don't want to get stranded out on the open road. Please let me know your expiernces with this motor or the 120ci motor. I would appreciate only first hand experiences. Thank you.

 

SU-WEEET!!!! No experience - but looking forward to reading about it in here!
Have way too much cash - huh????

 

Only thing I have heard about them is that there is quite a bit of vibration.

 

Really no extra vibration. They are noisy, but very reliable. I have 16,000 miles on my120 and have done nothing but oil and filter changes since. I have sold 5 120's and 1 131. I will post the Dyno chart for the 131. It was a 2008 with Rineharts and the stock throttle body, A.I.M. clutch and nothing else. Customer has 5k miles on it with no worries. Same customer has 25,000 miles on his 120 and no worries. I can say that his and my own 120 were the early ones that had the rear intake tappet bore issues. His had stuck a tappet in the case and mine was way worse. Jim's/Harley replaced both engines. neither of us have touched them since. they have since resolved that problemand are not afraid to talk about it. They identified and repaired the problem. I would not be afraid to ride mine anywhere. One of the 120's we did the Revolution big bore kit on and made 150 Horse. It is in a Nightrain with the 200 rear tire. Yeah.
I would recommend the 120 or 131, and have made several trips on my own Road King Custom to back up my recommendation.

 

Wow, 131cubes I'd love to ride something like that. I can't imagine the rush !

 

My best friend just put his 131 jims on his streetglide, it is defianetly badass. he was also torn between the 120 and the 131. He has about 1000 miles on it now, and has had zero problems. He does however have teh aftermarket throttle body for his tho. He has never had a full dyno run to get some good numbers I would imagine it will be pretty good I expect about 135hp and about 140 ft lbs. We raced a little bit from about a 20mph roll and he got me down low to the upper RPM range then I cam back around him. I expect that when his bike is broke in it may be a different story. he is also running D@D Boarzilla exhaust on it. Its loud and is all around a beast. His bike makes huge torque numbers even at less than 4000 RPM, hence the reason he pulle don me like he did.

 

I've got about 3000 miles on my 131. I originally had a 120 on this bike. The 120 blew up because of the old lifter problem as previously mentioned. If I remember correctly, it was the rollers on the lifter that actually failed. Jims came out with the Powerglide II lifters (now in both the 120 and the 131) with a bigger better roller on the lifter and a better roller axle oiling.

The 131 has some improvemenents. Huge ports that really flow. I think they have better valve springs.

I used a Harley Premium oil Cooler, but I would use a Jagg 10 row oil cooler if I was doing it again. The cam is now a .635 lift from the Jims factory. On the 120, it was a .650 lift. Bob Woods told me he had a better cam with different duration and .650 lift. When summer rolls around, I think I'm going to put one in and do the gear drive cam too.

By the way, these motors run pretty hot (like having a nuclear reactor between your legs) when you break them in during hot Texas summers. The heat thins the oil. The oil pressure drops....yada yada. I had the oil pressure relief spring replaced, changed to Amsoil 60W Racing Oil, during the summer break-in. I also put an oil temp gauge in and added a mechanical oil pressure guage.

These motors vibrate a little more cause you wanna drag race them a little more. I had exhaust flange bolts, oil pan bolts, air cleaner bolts and several other bolts vibrate loose and off. Treat the bike like your doing air craft maintainence. I also use the K&N oil filter with a lock wire on it after the Oil filter vibrated loose.

All in all, the bike is scary powerful and I would not trade it. Good luck, Steve

 

Just curious, what kind of quarter mile times can be expected out of a 120" or 131" with typical mods?

 

Are opinions welcomed? If so, number one...Jim's makes a fine product. Number two...the stock clutch will not last long with either and I have doubts about the stock trans handling the 131. Ray

 

Thank you to all that have posted. Hopefully there will be some more!