Any end cap without some internal baffles and a spark arrestor is just a piece of tin. The stock too small twin tailpipes go inside the spark arrestor and do too good a job of quieting things down. My endcap goes inside the spark arrestor with a series of slots that breaks up the sound but allows for a free flowing muffler with spark arrestor barely louder than stock. The 1.5 inch tailpipe sticks out and curves like it should, but it is what's inside that counts. That Pingry's thing not only didn't fit, it was nothing more than a cosmetic tailpipe. Dyno testing is the key to all of this. Let's put these shadetree endcaps on the Dyno and see what really works! [img]i/expressions/face-icon-small-cool.gif[/img]

 

I was discussing this project with my chief fabricator yesterday. He has a new, unique idea about how to reduce the noise and increase the flow. We are starting prototype fabrication on this today and, as usual, I have every intent on dyno testing it. I wish the dyno results I get could be converted to a sendable computer format, but I do have hundreds of dyno runns testing everything I come up with.

Racers Edge, in Las Vegas[my dyno shop] loves to see me. And there dyno man doesn't want to ride anyone elses quad but mine. He says he is just disapointed when he gets on others. I got a kick out of that. He recently laughed at a Banshee owner that just had his motor built by Trinity and was proud of his results. He showed the owner my charts, and he wasn't near as proud of his Banshee anymore.

 

If you get it worked out, count me in for a couple of the modified end caps. Just tell me where to send the money.

 

Knutz,
Count me in on one if it doesn't make it any louder than stock (thats probably a long shot)...Oregon's dB limits are really *#&&%#@ me off.

 

It's a sure bet that it will be louder than stock. The stock exhaust is only puting out through 2 holes of about 1/2" each, to get flow this must be larger and if it's larger, it will be louder.

Sorry to say this, but I can't imagine anything that will increase performance and be as quiet as stock.

 

I used a second baffle, which I just removed last week for the dunes trip to Bowie. The second baffle wrapped around the spark arrestor with a series of slots cut by my chop saw. It was AS Quiet AS STOCK but with more low end punch. I am going to get a HMF slip-on for Xmas and would be willing to send Knutz my end cap and extra burrito baffle for evaluation and dynotesting. There's more than one way to skin a cat,
and I would like to know what the hell we're doing. That seat of the pants thing is like listening through your ***, as opposed to talking through it!
...... Knutz is the only one planning on making these things, so he might as well try as many as possible to find one that really works. It might be mine, if it is, he'll owe me a drink. If he makes a bunch of money off it, he'll owe me a girl to go with the drink!
.... It would be interesting to Dyno test the HMF, and stock pipe as well. HMF has great dyno charts for its' Raptor mufflers, but nothing on its' DS slip-on.
....But they say, blah, blah, and it is lighter and looks better. My end-cap has been torched real good, having been re-re-re done, and though it works, it is starting to rust and looking pretty bad.
.....Hey Knutz, I did get your check off for the waterpump seals BTW.[img]i/expressions/face-icon-small-cool.gif[/img]

 

I have the HMF slipon.
They told me that it was 2 more HP than stock. Most of the power is down low. Yes it is lighter, looks good & sounds deep. Not raspy like a FMF.
With my Turf Tamer rear tires & the HMF the DS is alot more fun to ride. The traction & low end power help. I've only raced a 400EX since the mods though. You know the outcome of that, but hey he asked...I need to find a couple of Raptors & Banshees [img]i/expressions/face-icon-small-tongue.gif[/img]
If you notice the Raptor dyno charts it's also just 2 more HP for a slipon. 3 more HP for a full system. The biggest gain they got was by installing a filter right to the carb. Not sure about that for me though. I hop in the creek every once in awhile.
Overall I'm happy with the HMF. I'll post a better report after a couple of races to compare my improvement.

 

I just got the HMF slip-ons for the DS and Raptor. They are straight through with no baffles or spark arrestor. Unless they have some kind of spark arrestor or quiet core available they are going back. Maybe keep the Raptor if they have a quiet core, send back the DS slip-on anyway. I really don't think this is rocket science, but this is nothing but glass pack technology here with the HMF. I think I've got better with my stock pipe and custom, butt ugly end cap. I kept the spark arrestor and substituted one large tailpipe with large internal baffle for the two tiny tailpipes and baffles. It is barely louder than stock, sounds great, and gives the same low end boost as my FMF that I sent back because it was too loud.
......Since we have nothing going on the Raptor exhaust, I hope they have a quiet core/spark arrestor for the Raptor, they are more likely to have one for the Raptor than the DS.
......I think I'll just put a fresh coat of B-B-Q paint on the DS end cap.[img]i/expressions/face-icon-small-wink.gif[/img]

 

Hey Fourlix, in a couple of days[maybe a couple weeks] I'm hoping to head back to the dyno to do some testing on end cap modifications. If your intrested, I would like to take yours as well, if you can spare it. We have several different designs that we would like to test, and one more wouldn't hurt.

I need input here guys, what is most important to each of you when looking for something like this? Price, Quality, Noise, Looks, Performance, etc... You folks can be in on the design and development of a new productfor our DS, but you have to tell me what's important to you, and in what order of importance.

I know we want everything, but please place things in the order of importance. I can't make an end cap for $1 that's perfect quality, looks increadable, is silent, and creates 50 added HP.

The leading design of our modified end caps is top quality, makes great power[no dyno #'s yet] and looks really good, but it is loud and not cheap to produce. Are we on the right track? Would you prefer to lose some power to lose some noise? Would you prefer to lose some looks[polished stainless steel] to save some money?

 

Fourlix,
They do have spark arrestors. You need to order them seperately. The design on them is kind of cheap though.
Talk to Explor in the Yamaha & Polaris forums. He had a "quiet core" type HMF. It had baffles in it. He sent it back & got the straight through design though.
What were you expecting as far as design? My girls Big Gun exhaust is kind of the same thing, packing with a tube straight through.