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Spark arrestor removal wrr

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Curoiusity got the best of me and I had to see what was under the spark arrestor. If you decide to do this make sure you use a rust penetrator on the bolts. All 3 of my bolts galled on the way out. Now I have to buy new bolts and tap out the threads on the muffler.

On the upshot at least now I know whats down inside of there, bad part is that whats down there doesnt look too promising. All of the exhaust passes through the cat and is forced through a tube around 1 1/4" in diameter with the end capped off and a series of approx. 1/8" holes around 1/2 the circumference of the tube, not exactly a high flow set-up.

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here is what I did.

exhaust.jpg

exhaust2.jpg

It is lighter. I could drop a drum of napam here and not light a fire though.

Specs on that tube please:D ID and the various lengths, hole size and count would be fine.:) Did you experiment with the holes? Why have holes anyway, they will disrupt any smooth flow you can get from the tube end...I'm just throwing this out, I have no reason to think it is true:D

Wouldn't it be better to turn that bevel the other direction, if you can't make a little "bell mouth" - what do they call them?

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Specs on that tube please:D ID and the various lengths, hole size and count would be fine.:D Did you experiment with the holes? Why have holes anyway, they will disrupt any smooth flow you can get from the tube end...I'm just throwing this out, I have no reason to think it is true:D

Ok. Here it is the ID is about this big.

hole.jpg

Really. The stock spark arrestor OD fit in the ID of the outlet plus about thirty thousands. I machined the inside of the tube to be the same diameter. I did a little experimenting with a half inch drill bit and it worked. I figured if the exhaust made it past the end of the tube and got bottled up in the end of the muffler, it could go out the holes (it would not have to crowd its way back down.) Eight holes total. The bevel on the end is where I cut it off in the lathe. I should have cut the inside as you said but I did not. I welded the tube to a quarter inch plate then turned it down and welded the tip on after. It is not much louder than stock.

:) Who knows, I am just playing here. I also figured if I did not like it I would make something else next week.

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master manipulator of molten metal :)

Thanks. Here is a couple for you.

rack-1.jpg

My skid plate.

skidplateonbike.jpg

Got another idea for the rack, it hit me in the butt on a steep down hill rutted section. Will probably make a different skid plate some day also.

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That reminded me of one I saw, except turned up (pipe rotated 180) with about a foot extension above the seat on it for an ATV. For fording creeks and such. I don't know how they snorkel the intake:)

From what I've heard on this board, it seems like you can control the volume (and I suppose the air flow) very well just from changing the configuration of the spark arrestor / end cap. Take off the end cap completely, the thing roars like an open pipe. Make it 1.3" ID, with no inside pipe, it's almost as loud. Put the stock one on, quiet as a purring kitten. It would be great to keep the stock exhaust and be able to tune it a bit to match other mods.

If you can make me a plate with and outlet to fit a 2" (50.8mm) inlet, I'll get a Supertrapp 4" "discs only" setup so I can do some tuning myself. The ST disc thing is SA approved, so I think it is just the flange and the 50.? mm outlet that is needed. The ST 444-2503 is $60. If you want an ST to play with, I'll get two, we can swap. Any interest? Think that setup would be able to go quiet and also open up?

It would probably be as good performing as a $300 slip-on, and you can keep the exup and cat, and the durability of the stock exhaust. Tuneable to boot, and with some tinkering, around as quiet as stock.:)

Is there another tunable device like that?

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If you can make me a plate with and outlet to fit a 2" (50.8mm) inlet, I'll get a Supertrapp 4" "discs only" setup so I can do some tuning myself. The ST disc thing is SA approved, so I think it is just the flange and the 50.? mm outlet that is needed. The ST 444-2503 is $60. If you want an ST to play with, I'll get two, we can swap. Any interest? Think that setup would be able to go quiet and also open up?

Is there another tunable device like that?

Hermit

Is this the bazooka you had in mind?

bazooka.jpg

bazooka2.jpg

I beveled the inside edge as you suggested. Just have to drill the holes to bolt it on for you. Yea, go ahead and send a shim kit. I have a used one with a load of shims if you want.

Actually I have to cut some firewood this weekend but will take what I have and see what I can do for you.

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Wow.. that is a piece of art! I salute you! :)

Now I really feel like cutting open my welded SA and save some cost in the aftermarket exhaust :D

by the way... has anyone tried to put FMF Powerbomb together with stock muffler? :worthy:

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Hermit

Is this the bazooka you had in mind?

bazooka.jpg

bazooka2.jpg

I beveled the inside edge as you suggested. Just have to drill the holes to bolt it on for you. Yea, go ahead and send a shim kit. I have a used one with a load of shims if you want.

Actually I have to cut some firewood this weekend but will take what I have and see what I can do for you.

Wow! That looks lile the cat's pajamas.:D There's no rush for me, this lets me run the stock exhaust and then bolt this on in 2 minutes. So cut your firewood. Will get one mailed ASAP, and thanks a million BSS!:)

For those interested an exploded pic of the ST 444-2003 (in the above post I gave 2503, which is for a 2.5" inlet, not the 2" I wrote about) is at

http://store.summitracing.com/partdetail.asp?part=sup-444-2003

The idea being you can keep the catalytic converter, pitch the stock end cap and SA, and replace it with a tunable end cap, adjustable as you make changes to get the performance and sound volume balance you want. The ST part with BSS's end cap does just that. And its an approved SA:D

Cheers!

/dh

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Got another idea for the rack, it hit me in the butt on a steep down hill rutted section. Will probably make a different skid plate some day also.

Hey! You're an artiste!

Need to have some mule tough - yet practically invisible of course - form-following racks for this bike that a guy can strap half a dead elk to. If I can ride my mountain bike out (downhill all the way) with a dead billy draped over the frame in front of me, getting a couple of elk quarters on a WR250R should be possible. Those ones from cycleracks.com look like they would do it, but I wonder if they're unnecessarily wide.

On the other hand, I imagine when they were fabbing the design up, nobody piped up and said "Let's make them wider than they need to be!"

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The idea being you can keep the catalytic converter, pitch the stock end cap and SA, and replace it with a tunable end cap, adjustable as you make changes to get the performance and sound volume balance you want. The ST part with BSS's end cap does just that. And its an approved SA:

"Tuneable"???

Forgive me if I'm not following as I'm kind of racing through all of this before heading out on a GPS job. But are you guys talking about a mod that leaves you with the stock pipe with the benefit of being quieter and/or more power? You're taking the SA can off inside the pipe, throwing some bigger diameter pipe in there in its place along with some sort of shims that have a SA effect?

Anything as simple as what I'm glancing at that gives more power, I'm interested in. Anything that makes it quieter, I'm interested in. Anything that provides significantly more noise or is intended simply to provide a more pleasing sound to the ear, I'm not interested in. There was a time when the wail of a 125 motocrosser on the pipe was music to my ears, but these days, if they had an electric bike at the same performance and weight, minus the noise of the exhaust, I'd buy it.

Have to give this a closer look when I get back, but I am curious.

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"Tuneable"???

Forgive me if I'm not following as I'm kind of racing through all of this before heading out on a GPS job. But are you guys talking about a mod that leaves you with the stock pipe with the benefit of being quieter and/or more power? You're taking the SA can off inside the pipe, throwing some bigger diameter pipe in there in its place along with some sort of shims that have a SA effect?

Anything as simple as what I'm glancing at that gives more power, I'm interested in. Anything that makes it quieter, I'm interested in. Anything that provides significantly more noise or is intended simply to provide a more pleasing sound to the ear, I'm not interested in. There was a time when the wail of a 125 motocrosser on the pipe was music to my ears, but these days, if they had an electric bike at the same performance and weight, minus the noise of the exhaust, I'd buy it.

Have to give this a closer look when I get back, but I am curious.

A better look here, and a selection:

http://www.supertrapp.com/product_sections/cat.asp?CatID=27

I don't know what "disc only" and "adapter only" means. I may need to order two things that go together. Anybody familiar with these?

Of these I would choose: 3" discs for 1.75" pipe or 4" discs for 2" pipe. Smaller would be better, 3" or 4" for 1", 1.25, or 1.5" pipe. But one of these will do to start. Somewhere in the range will be a solution that lets people change on the fly from 80 db to 100 db, and find the best settings for them. I think the smaller pipe would be good to put more of the silencing in the big can, but I don't know, I've never experimented with mufflers.

Cost looks like somewhere between $25 and $100 total.

Cheers!

/dh

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Hey! You're an artiste!

Need to have some mule tough - yet practically invisible of course - form-following racks for this bike that a guy can strap half a dead elk to. If I can ride my mountain bike out (downhill all the way) with a dead billy draped over the frame in front of me, getting a couple of elk quarters on a WR250R should be possible. Those ones from cycleracks.com look like they would do it, but I wonder if they're unnecessarily wide.

On the other hand, I imagine when they were fabbing the design up, nobody piped up and said "Let's make them wider than they need to be!"

You should call the owner (number off their web site). He says that's who these were designed for - elk hunters. He said one guy complained about bending one. Turned out he had a trailer hitch mounted to it and was towing :) Settle in if you do call him, he's a friendly guy:)

I'm planning to mount saddlebags under the rack, at least on the left side. Use the rack for crash bars. I may mount a slider on each side:D

Oh, and when I mentioned wanting to mount the saddlebags under the rack, the owner said "Well, you can if you want, but that's where most folks put their scabbard." :D

I also bought his soft luggage. The materials used are excellent. He just started making them, so the finish is more workmanlike than refined - stitchwork, etc. Again, he said it's for packing out elk meat. It's pricier than the racks, but I think it will last just about forever, and it pops on and off the rack very easily. Like "in 10 seconds" kind of easily:D I'll start a new thread in a week or so, after I've ridden the bike a bit.

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You should call the owner (number off their web site). He says that's who these were designed for - elk hunters. He said one guy complained about bending one. Turned out he had a trailer hitch mounted to it and was towing .

Sounds more like something a dedicated moose hunter would do.

I'm planning to mount saddlebags under the rack, at least on the left side. Use the rack for crash bars.

So... you're planning on doing all your crashing on the left side???? I'm more of a random, free form bailer myself. Personally, I like to pick the most inconvenient spots with the most people watching to point and laugh. Builds character.

Oh, and when I mentioned wanting to mount the saddlebags under the rack, the owner said "Well, you can if you want, but that's where most folks put their scabbard."

Not me. Having seen what horses can do to rifles in scabbards, I've always had a sneaking suspicion that motorcycles and mountain bikes can do just as good a job. Mine travels slung across my back, not fixed to the bike where you can get some really good leverage going on the wrist of the stock and the barrel if you dump.

However, looking at this, that rack is indeed wider than it needs to be - unless you're planning on putting your panniers and/or rifle on the inside, of course:

bags1jpg.jpg

I also bought his soft luggage. The materials used are excellent. He just started making them, so the finish is more workmanlike than refined - stitchwork, etc.

That's what the wife is for: "Woman, get thee to thy labours doing that wifey thing, and make me some saddlebags so I may sally forth to do that hunter/gatherer thingy". She's pretty handy at making outdoor gear.

Of course, she's also pretty handy with a rifle or a bow, so maybe I'll word it differently than that.

Again, he said it's for packing out elk meat. It's pricier than the racks, but I think it will last just about forever, and it pops on and off the rack very easily. Like "in 10 seconds" kind of easily:D I'll start a new thread in a week or so, after I've ridden the bike a bit.

Hmmmm... no disrespect for the man, but you ain't going to get much elk meat in those, even completely boned out. I'm thinking of the rack as simply an attachment point: the critter stays wrapped in the cheesecloth, and then you strap and cynch the whole bundle to the rack. A load on each side, your packboard on your back also loaded, and you could move a fair amount of meat pretty quickly.

My personal opinion is that rack needs a diet plan to make it skinnier. Of course, I say that from a distance, never having actually seen a real one up close.

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Sounds more like something a dedicated moose hunter would do.

Maybe the guy was towing a boat:) Or maybe it was just a salesman's story.

Not me. Having seen what horses can do to rifles in scabbards, I've always had a sneaking suspicion that motorcycles and mountain bikes can do just as good a job. Mine travels slung across my back, not fixed to the bike where you can get some really good leverage going on the wrist of the stock and the barrel if you dump.

Same logic applies to what a rifle can do to the human spine. Plenty of leverage, and nice ends to dig in to the ground. But you do it in practice, I'm just speculating:D The hard case scabbards seem to be popular, that might help (for the "on the bike" case:))

Hmmmm... no disrespect for the man, but you ain't going to get much elk meat in those, even completely boned out.

I would imagine you are right. That is not my intended use, so it's OK with me. For all I know, his main customer base is squirrel hunters:D

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Maybe the guy was towing a boat:) Or maybe it was just a salesman's story.

Oh no... moose hunters would do just exactly that kind of thing. I left that fraternity back when I was a youth, before I had a chance to really ruin my back humping dead moose out of swamps on my back. Moose hunting is all about work.

Same logic applies to what a rifle can do to the human spine. Plenty of leverage, and nice ends to dig in to the ground. But you do it in practice, I'm just speculating:D The hard case scabbards seem to be popular, that might help (for the "on the bike" case:))

The usual Kolpin cases you see on quads (and some dirtbikes) provide cover from wet and some dust, and some impact protection. But where the hood slips over the boot really has no strength at all, and they bend/flex there. I've seen two rifles with the stock snapped in half at the wrist in those cases after an ornery horse rolled on them. That's why we always used to tell the sports to take their rifles out of the scabbards when they got off the horse.

I don't imagine it would be any different with a flyrod case, and I do the same thing riding with my trout slayers as I do with a rifle.

I just sling my rifle. On a sling, unlike with a hard attachment to a bike, it is much harder to get a lot of leverage happening on either yourself or the case. I don't know how much that would be true if you did the ol' flying W over the bars at high speed, but I think the greatest probability is simply a low speed drop of the bike in some difficult ground.

I would imagine you are right. That is not my intended use, so it's OK with me. For all I know, his main customer base is squirrel hunters:D

Oh, there's lots of elk hunters in Idaho. I can see stuffing those bags full of gear, it's the idea of stuffing some quarters of even boned out meat in there that I wonder about.

Anyways, if they'll let me cram enough gas and gear in there for a weekend loop of some of the local riding, then that is 90% of the battle already over. I just wish they were slimmer, that's all.

How about some detailed pics of those pannier's when you get them up and running. My wife will need a pattern....

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Hey! You're an artiste!

Need to have some mule tough - yet practically invisible of course - form-following racks for this bike that a guy can strap half a dead elk to. If I can ride my mountain bike out (downhill all the way) with a dead billy draped over the frame in front of me, getting a couple of elk quarters on a WR250R should be possible. Those ones from cycleracks.com look like they would do it, but I wonder if they're unnecessarily wide.

On the other hand, I imagine when they were fabbing the design up, nobody piped up and said "Let's make them wider than they need to be!"

Dude, not trying to bust your chops here, but why on Earth didn't you buy a quad? If you're hauling out elk quarters, why would you do it with a motorcycle? You can buy a nice 400cc 4x4 quad much cheaper. Plus, where you live even if it isn't legal you could ride on the roads all day without passing a car? Just wondering why you didn't buy a quad.

-mx'er

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Dude, not trying to bust your chops here, but why on Earth didn't you buy a quad? If you're hauling out elk quarters, why would you do it with a motorcycle?

Ummmm... because I haul a dead elk out of the sticks exactly one day out of 365 days a year?

That's assuming that I shot it somewhere that I can get to by bike in the first place. Many of them end up coming all the way out to the road on a packboard. And sometimes I get too picky about what I want to shoot and end up going home with nothing at the end of the season.

Ergo, not much point to buying a quad for one day a year.

You can buy a nice 400cc 4x4 quad much cheaper. Plus, where you live even if it isn't legal you could ride on the roads all day without passing a car? Just wondering why you didn't buy a quad.

Well, where to start...

First, we quad everywhere we aren't in a truck out here while at work. If I never got on another quad in my life, that will be too soon for me. They're just something that doesn't interest me, no matter how often I ride them. They're great for what they do, which is packing loads of crap. Beyond that, I have no use for them personally.

Second, I can ride a bike on every highway, forestry road, etc I want to go, and it's all perfectly legal. I'm not going to commute to a contract zipping down the highway on a quad.

Third, a lot of these old trails and roads around here, a quad isn't going to go unless you're prepared to plow through and make a small road in so doing. We don't need more of that around here.

Fourth, it is illegal as hell to ride forestry and development roads around here in a quad, and the CO's, police, forestry compliance guys, etc WILL ticket your ass - and when they get complaints from people about quads blasting by them on the forestry roads, etc, they go up there and write tickets. The fact you were riding responsibly and weren't the one who scared Pops and the kids means nothing to the guy writing the ticket. And maybe it's just a throwback to all the years I worked as a cop, but since I generally expect that other people will obey the laws I think are important, I kind of feel an obligation to obey the laws that other people think are important. I'm one of the first guys to raise hell about other people breaking various laws, so I would look pretty ignorant picking and choosing which laws I would and wouldn't obey personally.

And fifth, the Dodge diesel will easily haul a bike on a trailer hitch attached bike rack - the hitch is rated for 1000 lbs - while leaving the canopy on, and taking up very little extra space behind. That isn't going to happen with a quad.

Those are a few reasons.

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