I just wondering if anyone has had, or knows anyone who has had crank problems with a SE120R? I debating doing the timken conversion and welding the crank. I know it will obviously make the bottom end stronger but I am not going to be riding it that hard. I'm building the engine from the kit so the timken conversion will only cost $250.00 right now. I don't know how much welding the crank will cost.

 

I'm thinking the only way to blow these engines up period is to run em without oil...and even then they will run till they sieze.

 

You should ALWAYS do the lefty bearing conversion and weld the crank....if given the chance.

~Joe

 

If doing the kit, I think it is a no brainer. with that said, I have 6K miles and others I have stayed in contact with from the 1st round of 120's have more miles than me, no issues. One guy I read about sissored a crank but dont know the details behind it. I am all for over building (see sig below) would not bother if buying the crate but if you alreay have it coming in kit form, why not some extra insurance...

 

The owner of the local dealer I trade with took a brand new Road Glide Ultra 103 and replaced the engine with the 120R. The day after the transplant was finished he hit the road west to the dealers meeting and then to Sturgis before returning back to North Carolina. I don't want to mention his name but he is a true rider that can tell you the top speed of every bike he has riden, and there is no such thing as "BREAK IN PERIOD" in his vocabulary.

He ran this bike hard and told me it is by far the most exciting Harley he has ever rode on the street. However he lost a valve guide seal on the return trip and was burning a quart of oil about every 150 miles.

I can assure you that if he did not blow up this motor it must be pretty solid!

 

I'm still undecided. There's someone local who can do the Timken conversion, but he's supposed to be very slow but good. I really shouldn't be in a rush anyway.

 

I have no idea about welding the crank, as I am no wrench. From what I have read on this forum, you should weld the crank. Do they also perform a procedure that is balancing the crank? Probably at some point you will ride it hard just for fun. There is no way I could attempt what you are doing, but if you do the crank you should have done everything correct to ensure a high milage motor.

 

its winter, you ain't going anywhere. true, balance and weld the crank. darkhorse, or rev perf. do this they can also do the brg mod and set endplay for you. do not miss this o your build, you won't want to go back in once its broken, or starting to go bad, and just because it hasn't happened to anybody here, doesn't mean its not going to happen to you. these are still mass production flywheels and are not anywhere near exact. I say do it, I do all of my motors like that, guess what, I also have zero problems!!

 

A different subject about the 120 engine. I just returned from the dealer getting the rear brake light switch replaced. I ask a question about the cost of a 120 and the service manager told me that Harley will no longer allow the dealers to install a 120 in any Harley-Davidson.

Has anyone else heard this?

 

If your going to have it all apart,why not do it??It's cheap insurance.Your getting a 120R & your not going to ride it hard?? Yeah right!!!