Hey all;

Just had a Thundermaxx system installed along with Rinehart Tru duals on my 2003 FLHTCI.

Sound is great, power is great etc. The thing that seems to be out of ordinary
is low end stumbling. IE at lights giving the throttle a little causes the engine to sputter.
Similarly on speed reduction on the lower end without throttle it sputters and backfires
and if I add throttle it's like there is nothing there. The revs drop to 500RPM when clutch pulled in
and runs rough for a bit.

Shop says this is normal and I need to relearn driving technique. Huh? Also that if I want up end power
then this is the price. These guys have been pretty good to me (bike) but I wonder. They are using a "custom"
map not the generic one.

I accept that the HD ECM was designed for the whole power scale but this seems kind of off for me.

Is this "normal"?? Suggestions?

Thanks

Dennis

 

The only "driving technique" that I had to relearn was that I no longer had to anticipate
when the bike would unexpectedly stall or surge, while simultaneously roasting my "chestnuts".

 

If you got the Autotune module with it, you may just have to ride it for a few days for it to "learn" the proper AFR. Sounds like they used a poor base map to start from. If you have your SmartLinkIV software installed on a laptop, you could upload one of Zipper's base maps and might get it running better sooner. Otherwise, just ride it for 30 miles or so. Then shut it off, start it up, and ride another 30 or so. Shut it off, start it up, and keep doing that in order to get it to learn what it needs.

 

You may also want to check the MAP. Sometimes the MAP Zippers loaded into the ECM before shipping is not the one your bike should use, at least that was the case in my Zippers ECM. Your symptoms should not be happening regardless of how much time you allow it to tune. Off idle stumble is not right. The best thing to do is review their MAP listing and definitions, and see which one is closest to your build.

Good luck

 

My T-Max has never given me problems like those that you are experiencing. It could be a problem with the map; it could also be the IAC (idle air control) that is causing the problems. Has the shop that installed your T-Max installed several of the systems or is the procedure relatively new to them.

Arcane

 

Arcane brought up a VERY important point. If the IAC is not properly set, your whole tune will be off.

1) Check to make sure you have the right MAP for your build
2) Set the IAC correctly according to the T-Max manual

Good Luck

 

I hate to sound like a total dufus but is the IAC part of the
T-maxx install or is it part of an existing system?

Thanks

 

The IAC is part of the existing system that is controlled by the Zippers ECM. If it is not set correctly, then all you other values and adjustments will be off. It's all in the T-Max manual that came with the CD ROM.