ECM Replacement Thundermax to Screaming eagle or?

Messages
22
Folks super newb to the world of modern Harleys with ECMs- The road glide with the 120R that I bought was running rich so I started poking around and noticed it has a thundermax ECM which isn't legal in California and it is missing the 02 sensors and apparently I can't even order from Thundermax as it won't let me enter my state in the order form.

I am thinking it might be quicker, easier and in the longer run, more legal to put another ECM on the bike like a screamin eagle or something else. I've never changed out an ECM or touched one before yesterday so easy is kinda BS.

Or is this something sensors from other ecms will work? I imagine many of these have the same connectors.

It is unfortunate since my girlfriend is coming over from her home country of England this week and we were gonna do some cruisin- And since she is a fiery red-headed lawyer (except when wearing the goofy white wig they wear in court even if she makes it look hot) she'll probably sue me for something :) Guess she'll have to ride the P pad on the rigid- and give her something else to sue me over. :)

Any advice appreciated...
 

bluecollar84

Well-Known Member
Messages
703
I am also in Cali, and run the non cali version of T-Max. I would suggest one of 2 things. 1. Call zippers, Fuel Moto or Dragos one of those 3 will get you the parts and support you need to run a T-Max. 2, Find a local dyno Guy and have it tuned and be done with it all together. Local to me (Fresno, CA) is Chris Rivas V-twin, I know 3 guys that have used him to tune their bikes and all were happy. I believe its $600 and he uses your Harley ECM so all told a pretty good value. You have to bring it on a trailer though with the plates removed. Good luck with your ride!
 
Messages
22
I am also in Cali, and run the non cali version of T-Max. I would suggest one of 2 things. 1. Call zippers, Fuel Moto or Dragos one of those 3 will get you the parts and support you need to run a T-Max. 2, Find a local dyno Guy and have it tuned and be done with it all together. Local to me (Fresno, CA) is Chris Rivas V-twin, I know 3 guys that have used him to tune their bikes and all were happy. I believe its $600 and he uses your Harley ECM so all told a pretty good value. You have to bring it on a trailer though with the plates removed. Good luck with your ride!

Very cool thanks for the scoop- so have you ever had any issues? Can't say as any of my bikes have ever been checked out by the man but they have been too old to test.
 

bluecollar84

Well-Known Member
Messages
703
There's no man to check your ECM in California. It's only on the sale side where the regulation is not the possession side. How does a 120R run around without O2 sensors? For a high dollar engine that seems a bit backwoods to me. You sure its actually a 120? Plus getting new sensors is gonna be way cheaper than paying Harley for a new ECM plus the service time to program it. Make sure your exhaust has 18mm bungs in it, call one of those guys to order new sensors and you'll be riding by this weekend no problem.
One of the guys I know of had bought a road glide with a 120R in it. Same issue, bad gas mileage ran rich and not real impressive power. His had a SERT though. Had Rivas dyno it and it was WAY off. Came back at 140 HP! A standard 120R wont make that so Rivas told him was definitely not stock 120R parts. The other guy I know had a TMAX and hated it. Wouldn't run right blah,blah,blah. Turns out it had 107 with head work and all his base maps were for 96's (bought it used, 2010 SG) and he never wrote the learned curves to the base map so yeah it was a turd. Rivas straightened it out and runs like an ape now.
 
Messages
22
Thanks again for the info I really appreciate it.

How does a 120R run around without O2 sensors? That is a really good question- So it had low miles and while it has really good stuff on it- it was clearly just a show bike- which is fine because I'll get it where it needs to be to ride daily. I am a newb with this stuff so I am guessing maybe he just fudge the numbers on the program?? Not even sure if you can do that.

I couldn't order the O2 sensors off the T max site- it won't let you put in the state of California. I did find that Rolls Royce phantoms use the same Bosch wide band sensors (18mm) so I ordered two of those. For each around 100 bucks less than Tmax.

Unfortunately, I also fly out this Sunday to do some stuff with Interpol and Europol at the Hague in Netherlands so I'll see what I can get done this week and hit it again when I get back in 2 weeks.

Oh and typical of my luck- I was working on it Friday afternoon in the driveway (up in Santa Cruz mountains) cause it was nice outside- I had gone inside to use the head and grab a beer and a delivery truck came down the driveway to drop something off. I go outside as the truck is going up the driveway and I notice the bike is laying on its side cracked the fairing- I was super happy to see that and it made me warm and fuzzy inside- Just kidding I am a bit pissed.
 

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