Hey guys, i really like the look of the 18 fat bob exhaust set up. i have been contemplating doing a big bore upgrade but there is the recommendation to get a new header/exhaust to get the most out of it. I really do not like what is out there as almost all the set ups change the look of the fat bob. The one i might consider is the Bassani road rage 2 or 3 in black. I have called around and no one makes a replacement header for this model so the original set up can remain the same. I have also read that the M8's are really picky with the exhaust set ups that in some cases it will cause a tq curve dip and it can not be tuned out. In that specific case, the guy just put the stock header back on and it regained the tq curve with a slight performance decrease. The last thing i want to do is spend $800 plus labor and tuning to find out that this is the case or that the increase is minimal over stock, meaning not worth the $ to not gain much. Not sure if anyone with the fatbob has tried the bassani rr with great success or found a company that does a replacement header to use with original set up. Thoughts?

 

 

I thought about these but per the S&S website the dyno graph they have it shows those dips I was talking about. It might not seem like a big deal but to me, I like the smooth tq curve, especially if i am spending over 1k.

 

FuelMoto has been getting pretty great numbers out of their M8 Softail big bore kits using D&D exhausts. Have you looked into them?

 

Yes, have but the Fat cat which is the one they use just does not do it for me. i know that i should not base everything off of looks more so performance.

Decker72, i see you have the bassani, how do you like it? how much of an improvement was it, not sure if you dynoed or not..

 

 

Agree.
Too bad the stock head pipes are so BIG, something like the S&S 2-2 really fit the look of that bike better.
I wouldn't fret about a graph dip that can't be felt seat-of-pants.

 

I really like the look of the stock exhaust, and I pretty much hate the look of most aftermarket exhaust systems. The D&D is showing great numbers, but... Blech as far as looks.

Like the OP, the only one I have found that I have even warmed up to, looks-wise, is the black 1S52RB from Bassani. It retains a similar routing of the headers around the timer cover, and has a little bit of upsweep. As I understand it the heat shields extend down to the 2-1 collector, so you could get the heat shields coated bronze and retain a somewhat similar look to the stock bike. If they have a heat shield that covers the collector up to the start of the muffler, that would be even better.

As for performance: I can't find any direct comparison of what the exhaust really does for you, by itself. Every test I have seen, they always combine some other parts with it. S&S, for example, shows charts of before and after, but not of just the exhaust, but of the exhaust AND their air cleaner. So how much improvement is due to the exhaust, and how much to the a/c, and how much to the tune? Apparently nobody wants us to know that answer.

However, look up ADM's chart. He changed out his stock headpipe and S&S Grand National mufflers on his Fat Bob and replaced that with the Bassani Road Rage, and then had it tuned with a Power vision (IIRC). The gains were pretty significant, a massive gain in torque of around 20 ft/lbs all through the lower rev range, and even picked up a few hp on the top end. So a pretty big boost, not as big as stock-to-Stage-II, but still a big boost. Enough of a boost that I am coming around to doing the same thing for my bike this Fall when the warranty expires.

 

Oh, and as far as the S&S 2-1-2 goes... I saw that but I can't figure why I would want it. The performance gains they show are about the same as what they show for the stock headpipe and their slip-ons, and that's a much better looking combo for a lot less money...

 

here's ADM's dyno chart. As I understand it, the red line is stock headpipe (decatted) and S&S Grand National slip-ons and the Harley tuner. The blue line is with the Bassani and a Power vision tune.


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