The Thunderheader Pipe Is Installed : V-Twin Forum: Harley Davidson Forums

Old_Mil · 10-02-2004, 10:16 AM

Put the 2-1 Thunderheader on my FXDX this week. Got the chrome one with the front and rear heatshields.

All I can say is: WOW. This is one amazing upgrade. The acceleration of the motorcycle vs. the stock exhaust is significantly better and speed for speed, the engine is running about 200 RPM slower than it was with the HD pipes on there.

Amazing. Nice Sound too; although I think I liked the sound of the V&H straightshots on my Sportster better, the performance gain with the Thunderheaders is amazing.

barry1967 · 10-02-2004, 10:41 AM

Had one on My FXDL when I had it. They now make em for 04 sportys. Must not cave to temptation.....must fight urge....can't stop....

dave0924 · 10-02-2004, 03:39 PM

Old Mil,

I put a Thunderheader on my FXDL a few weeks ago and I agree, they make an amazing difference.

Got any pics? Here's mine:

http://home.cinci.rr.com/hardball/lowrider.htm

JagmanR · 10-04-2004, 10:33 AM

I took of VH Straightshots and replaced with a chrome Thunderheader. It made my bike perform much better. The bike feels better tuned, more precision, smoother while still giving me a nice loud rich sound. I do admit to missing dual pipes on occasion however and the louder sound they offer, although I think my TH looks great on my 03 Fatboy and everytime I ride it, I'm reassured of my decision.

OrangeTJ · 10-04-2004, 11:13 AM

Congrats on the new pipes. Thunderheaders do sound amazing, and I hear great things about their power producing potential. I'm a little confused by your statement about rpm's at a given speed, though. Wouldn't your gearing have to change for your rpm to be different at a given speed? Given that there's no "slush box" between the rear wheel and the output shaft of your bike, how would the rev's be different?

Old_Mil · 10-04-2004, 11:43 AM

Quote:

Originally Posted by OrangeTJ

Congrats on the new pipes. Thunderheaders do sound amazing, and I hear great things about their power producing potential. I'm a little confused by your statement about rpm's at a given speed, though. Wouldn't your gearing have to change for your rpm to be different at a given speed? Given that there's no "slush box" between the rear wheel and the output shaft of your bike, how would the rev's be different?

That was probably the most surprising thing to me. Get up and go I can understand, but with no changes to the tranny, this is something that made me scratch my head. But the evidence on the Tach is undeniable...what once took 3000 RPM to achieve is now taking 2800...There might be something else going on - perhaps a simultaneous tach problem - but for the life of me I can't figure out what.

OrangeTJ · 10-04-2004, 11:58 AM

Quote:

Originally Posted by Old_Mil

That was probably the most surprising thing to me. Get up and go I can understand, but with no changes to the tranny, this is something that made me scratch my head. But the evidence on the Tach is undeniable...what once took 3000 RPM to achieve is now taking 2800...There might be something else going on - perhaps a simultaneous tach problem - but for the life of me I can't figure out what.

Weird...whatever is going on, it sounds like you're happy with the outcome!