Thoughts on the Thundermax
Seasoned HDF Member
Joined: Jul 2008
Posts: 9,282
Likes: 1,139
From: southeast PA
I've been running mine for 8 years and no complaints. Can't be happier with the way the bike runs. Customer support was great when needed.
A couple of weeks ago I thought I felt there was something off so I hooked the bike up to the laptop and found out one of the O2 sensors went bad. Easy fix.
I just put in a set of TTI's and through the ThunderMax I've been able to see how much more efficient they are when it comes to the auto tuning process.
A couple of weeks ago I thought I felt there was something off so I hooked the bike up to the laptop and found out one of the O2 sensors went bad. Easy fix.
I just put in a set of TTI's and through the ThunderMax I've been able to see how much more efficient they are when it comes to the auto tuning process.
Seasoned HDF Member
Joined: Sep 2007
Posts: 9,741
Likes: 1,599
From: Danbury CT
Mine has been great but make sure to pick a close map. There aren't many cam choices, mostly red shift. They told me to use the red shift 575 map for my woods 555's. Bike ran like s*** and had lots of pinging. Acceleration was very flat too. The timing was set way too high on that map some as much as 12* too high. So I picked out the red shift 525 map and it was night and day. Timing was much lower. No ping. Ran a few auto tunes and it's flawless. Mine has the older serial port connection and it's very slow to read and write. 3 beers worth.
Thanks on the input guys. My bike is currently stock motor wise with the exception of intake, v&h big radius, and the SE tuner.
I went and talked to a very reputable local shop that my dad has taken I bike to for over a decade, and was going over some build ideas. He recommended the thundermax, and said your bike would never outgrow it, no matter what you threw at it. But I am planning on a set of cams and adj push rods with some headwork next spring, so I figured I could get a little taste now.
I was also pondering the idea of going ahead and getting the cylinders bored and getting some good headwork with some oversize valves, so the cams would match, or is there a set of cams I could run with just mild head work, that could later be matched with oversize valves and overbore?
I went and talked to a very reputable local shop that my dad has taken I bike to for over a decade, and was going over some build ideas. He recommended the thundermax, and said your bike would never outgrow it, no matter what you threw at it. But I am planning on a set of cams and adj push rods with some headwork next spring, so I figured I could get a little taste now.
I was also pondering the idea of going ahead and getting the cylinders bored and getting some good headwork with some oversize valves, so the cams would match, or is there a set of cams I could run with just mild head work, that could later be matched with oversize valves and overbore?
Last edited by Levi Weuve; Aug 29, 2016 at 10:47 PM.
Intermediate
Joined: Feb 2016
Posts: 47
Likes: 4
From: Port Orange, Florida
Why get the cylinders bored when you can go to an HD 117 for $2500. They can do the mod when they do the cams
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Road Warrior
Joined: Jan 2012
Posts: 1,392
Likes: 21
From: Delaware
I've used one for a little over a year and really like it- replaced a Power Commander V with it. I get zero decel pop, zero "gurgling", and a very smooth power band. One thing though for anyone with the '08 and down "Y pipe" header- it doesn't like that and tries to richen up the back jug constantly due to the location of the O2 sensor. It'll run like a raped ape when moving and with good exhaust flow, but it will pop a lot on decel and idle.
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Cruiser
Joined: Feb 2012
Posts: 103
Likes: 3
From: RI
I have it installed on my SG. 3rd season, no issues. In my opinion, they are great if you have a lot of mods but if you have a cookie cutter setup (stage 1), a simple tuner from any mfg and a canned tune will do the job.
thundermax
my tuner is a year and a half old on a 2014 limited i had experienced a lot of starting issues which thundermax owned up to quickly but not before a 3000 mile road trip where i had to start it 4 or 5 times when hot to get rolling. To be fair they always responded quickly to email and sent new maps when i requested . they also acknowledged the starting problem and fixed it . bike runs better cooler and faster than stock and sounds better with the stage one mods. i had to bug them to get gas mileage over 30 again but they sent me new maps.
i would rather have no problems but this company fixed the issues i requested
i would rather have no problems but this company fixed the issues i requested