HPI Stainless Exhaust Systems

[Ohio HD]

This is a question in general about the HPI exhaust systems. I haven't ever seen one, and have no intention to buy one as I have a Burns system.

Are these any good at making horsepower? I wonder because I see a lot of these for sale as new, or with "2,000" miles etc. I've yet to see a dyno sheet anywhere with an HPI system, so I have no idea. I guess if they do "OK", then the stainless is just a nice looking feature. Read as $$$

The system I have from Burns, Vince said he's seen a TC make 180 hp naturally asperated. And he's seen an M8 make 200 hp naturally asperated. Burns has a larger system than mine for all out competition. He says he doesn't see these used on street bikes. But has seen 225 hp on an M8 with one of the competition systems. 

So I wonder about the HPI systems, if they're any real improvement over systems like D&D, Bassani, RB Racing, etc?

[kd]

Did you see these? 

https://www.horsepowerinc.net/exhausts

Even though they do offer tuning there I don't see any posted graphs with their pipe.  If you click on the first image you will find a  full view pic.

[Ohio HD]

Yeah, I've seen them in photos, I meant I have never actually seen them.

The only dyno sheet I saw was a stock bike, then compared after exhaust was added, and air breather. It didn't look to be anything special. Same type of improvements you would expect with any good system with a tune.

I've been watching out at the HD race groups and haven't seen one show up yet on anyone's bike.

[kd]

I have a LOT of respect for HPI but from appearances alone I don't see how they can compare to the Burns pipe you have.  They have been tested lots with the info shared.  Maybe that will eventually happen with HPI but I still am not that confident it will outperform the Burns pipe.  If you look through the contenders at the drag strip you see a lot of Burns configured pipes.  I see the HPI like configured aspects are showing up in the King of the Bagger series bikes but that's another type of use all together.

[Ohio HD]

Based on this single dyno sheet I found. They look to be designed as a intermediate use pipe. Not really for high end motors.

Notice how the curve follows the stock pipe curve. 9 hp and 7 torque is what I'd expect to see with any decent pipe over a stock system. Assuming that the stock system also had a converter in there.

[biggzed]

I have also been wondering what the hype was on these. They are the hottest thing going in the M8 softail market. I see 5-6 posts a week ISO on some Insta group I joined. They seem to be hard to get a hold of. I wonder if the scarcity is driving the demand vs the pipe actually being a top performer. Everyone wants what no one else can get. I like the looks of it alot, but not enough to pay that price.

Zach

[kd]

That's what a well built complete stainless exhaust sells for.  The question is will it support your needs?  There are some that cater to power building and others just for looks.  That's where it's important to do your homework.  Even though Ohio has already done that and made his decision based on needs, researching combinations that are like yours will give you an idea what to expect for the money you spend.

I always look at the cost of power as $100 / hp.  If you get that or better IMO you're doing al right.

[rigidthumper]

Inflation has that up to $200/HP 

[kd]

No kidding. 

[jmorton10]

I'm curious, why does only the BAKER tranny need an extra $135 bracket on top of the $1700 system ??

~John