• BDX S1 Performance Exhaust for GY6 Buggies · My thought process on the design

  • Let's talk about new parts and solutions to common problems you want to see with a BDX logo. -T@BD
November 2019 Forum Retirement
Due to lack of extra personal time (and too much spam), I'm retiring the forum and setting it to a read-only state. No new registrations or posts will be accepted as of 11/09/19. However, all information will stay up and searchable. If you spend a few minutes searching, you'll find the answers you're looking for. We may re-open the forum next spring.
Let's talk about new parts and solutions to common problems you want to see with a BDX logo. -T@BD
 #12679  by Travis @ Buggy Depot
 Mon Aug 13, 2018 11:53 am
Marketing aside, I want to take about some of the logic behind development of this exhaust. Here were the main design considerations:

1. Price and value. More power per dollar was the focus
The goal for this exhaust was to be directly comparable to the $300 Hammerhead Performance exhaust in terms of performance, but cheaper by at least half. It's always really bugged me that a good sturdy performance exhaust costs almost as much as a new engine. The HH exhaust looks great, but I think there is value in cutting out the aesthetics and having an option that just goes for the performance.

I dyno'd the HH Performance muffler years ago and saw a (tentative) increase of 6.5%. An extra half horsepower (.55hp). This is outstanding for a single modification, and I expect the BDX S1 exhaust to perform the same as it shares a common straight-through no-baffle design. I'm eager to get the dyno back together and developed to the point that we can get true precise head-to-head numbers.

I'm not knocking the HHP exhaust. I own them on my buggies and love them. But even as a dealer, I've never been able to justify installing them on all of my GY6 buggies. The BDX exhaust is meant to be affordable enough to go on every buggy in your garage, no matter how many you have.


2. Heavy header construction. I want it to last the lifetime of the kart.
Stock exhaust headers tend to crack with age. I wanted to make sure that ours will last longer than anything else on the kart. The flange that mounts to the engine is 1/4". That's not going to warp like the stockers either.


3. Universal silencer options. Nothing proprietary
I don't want to spend months R&D'ing a unique silencer (muffler) design and some type of unique mount to the header. HH and others in the past did this and it locks you into only being able to get replacement mufflers from them. I decided to use the standard universal 51mm header outlet on our exhaust, so you can use whatever sportbike slip-on you want later. The slip-on muffler that comes with our kit is a no-frills, no-nonsense muffler that gets the job done and doesn't inflate the price of the package. But you're free to use whatever slip-on you want less than 400mm or so long.


4. Further reducing the price to $99 (but you shouldn't wait)
My plan is to eventually drive the BDX Exhaust's price down to $99 through volume. It should become a no-brainer first upgrade at that point, along with our other S1 performance kits. Don't wait though, I can't lower the price if people are waiting and not buying.

Also - a big shout out and credit to my team
This was their first independent R&D project and they absolutely hit a home run in my opinion. After communicating the design parameters, I stepped completely out of the way and they nailed it!

If you've been following along with the shop since January, you know some of the decisions made here over the last year to either double down on in-house shop products, or let them go entirely. It was a saga and there was a fair amount of suffering involved. I feel that we're at the point of all that paying off. Not only in terms of paying the bills, but also by being able to make more options like this available for the community.

As for how we like the pipe, there's only one more thing to say:

And a big thanks to our 2018 Front-end Kit people, y'all made this possible. Coming out of that project, we now have the right people, we've got all of the equipment, and the processes are much more efficient. Things are looking really good moving forward.

 #12680  by CheethaSpeed
 Mon Aug 13, 2018 7:25 pm
Looks pretty sweet. Your gonna make me get a gy6 aren’t you? For me personally I’ve always said your custom stuff is what sets you apart and draws them in. Got me. I still have an exhaust to get for mine and it won’t be from a generator-I promise. It would nice if I had this option. Dang all custom is too much custom. :cry: I dont have a team to brag on :cry: Looks great guys!

Excited about these tapered bearing HD Hubs! You saw that didnt you?
 #13168  by Travis @ Buggy Depot
 Sat Feb 09, 2019 1:31 am
wilit wrote:
Sat Feb 09, 2019 12:13 am
I'm in California and I have to run a spark arrestor in my exhaust. Does the baffle insert have a screen that acts as an arrestor?
Yep, we add a stainless screen insert between the header and muffler to act as a spark arrestor. Used US Forestry Service documentation as a guide to work out the proper specs. (y)