Flying Dogfish Air Cleaner

GoldenMotor.com

silverbear

The Boy Who Never Grew Up
Jul 9, 2009
8,325
670
113
northeastern Minnesota
You may think this is an old movie you've seen before called, "The Leaping Tuna Air Cleaner", but this is the sequel and is bigger and better and shinier and is not for the china girl, but for the 4 stroke Greyhound engine. They do have things in common, for instance they smell alike having started life as tuna fish cans, but as you can see in the photo, this baby is bigger and mucho better. Anything is better than that honker of an air cleaner that comes on it. A big rectangle of plastic. When I saw a picture of Jim Davis Corvette build with that cool Whizzer air cleaner on his I knew I had to do something. So the same high technology comes into play with this one and the price is right.
You'll need the big size tuna can and a can lid of the same diameter. I went to town this morning for hardware and stopped in the grocery store for air cleaner supplies.... the can of tuna, a big can of krautand a stainless steel pot scrubber. Around five bucks and you get to eat the contents.
Open the tuna can in the same was as the smaller version using a small punch (ice pick will work) to punch holes in a circle to open the can. Don't use a can opener since you need that big lip in order to close it up again. Look at the pictures and you'll understand. Connect the dots with a small knife and tack hammer, going from one hole to the next. I cleaned up the roof edge with the dremel tool and a grinding bit. You can use the intake manifold gasket as a template on the bottom of the can to determine the bolt holes and the opening for the carb to take in air. Drill the holes to size and try it for fit, being sure you have room for the choke lever above to clear. Mark the spot where the breather tube is going to go.
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silverbear

The Boy Who Never Grew Up
Jul 9, 2009
8,325
670
113
northeastern Minnesota
I use a cone shaped bit to open up the hole for the carb to draw in air and drilled a hole for the breather tube. I put it in place and then marked half way up on each side to determine where to have breathing holes in the can and where to stop. I didn't want for water to be able to get in if it starts raining hard while I'm riding, so the breather holes go on the bottom half. You might think this is not enough and the air intake will be restricted over the stock air cleaner, but take a good look at the inside part of the stock one. Don't be fooled by how big the thing is overall. It will breathe. Punch exactly the same number of holes I did. This is important. Less holes and your Greyhound will choke to death. Too many holes and it will catch a cold. I determined the exact number using a Ouija board and tarot cards. i stuck the stainless steel pot scrubber inside so you see what I'm up to. If you are uncomfortable with the idea and don't think it will be the cat's meow then use foam and you can even cut up the pieces from the stock one... but you'll need to figure something to go between the carb and the foam to act as a spacer. Take a look at the way the stock filter was set up and you'll see what is needed. The scrubber I'm using won't lay flat against the manifold, so I don't need to worry about it. I'll oil mine a bit first and when I clean it periodically I'll oil it again. The oil will help to catch dust and wee little nasties like Minnesota's mosquitoes which are more like small birds. Attach the filter to the manifold and cinch down the nuts. Put the scrubber in.l Oh yeah. I forgot to mention the three screws (only had three) to hold the lid in place.
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Dan

Staff
May 25, 2008
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I like it! Looking forward to your final pics "Silver bear, AKA Tin Snips, PI"

Is on the list of "how can I mess with the HF any more" but have you tried removing the spacer between the engine and carb? Would give lots of room. I am gonna lose the large shroud and was wondering if that spacer would have an effect.

Any way, as always, looking good SB! err, I mean Mr Snips.
 

silverbear

The Boy Who Never Grew Up
Jul 9, 2009
8,325
670
113
northeastern Minnesota
And that's it. Before mounting mine I ran over it with a wire wheel to give it a bit of shine and then shot it with clear coat under the theory that it will keep it spiffy. We'll see. I think it looks pretty good for a five buck air cleaner and a whole lot better than the stock one. Now I have to figure out what kind of dish combines tuna fish with kraut...
SB
 

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silverbear

The Boy Who Never Grew Up
Jul 9, 2009
8,325
670
113
northeastern Minnesota
Thanks, Dan. I have no idea what effect removing the spacer would have. I've only had this motor a couple of days, but I don't really mind the shroud on it. It isn't offensive anyway. The orange one on the HS motor is another story, not so bad black, though. I'll be interested to see what you Greyhound looks like with no coat. Skinnier no doubt. I thought about painting the shroud black, but I don't mind the blue color, goes OK with the bike it's going on. I've decided not to do a copper exhaust pipe, but will use the flexible pipe instead. it will be nice when there's more aftermarket for these four stroke motors. I ran the Greyhound for about twenty minutes before removing the gas tank, etc. and liked how easily it starts, runs smoothly and sounds pretty cool with that low idle. Think its gonna be an OK motor.
SB
 

Dan

Staff
May 25, 2008
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with too much air, what did you mean "catch cold"? My air cleaner is, well you have seen it, some wire over the OEM foam.

My question is, can they be getting too much air hot? After reading your post looked it up and around the inter web but surprisingly enough, found some conflicting thoughts. lol
 

silverbear

The Boy Who Never Grew Up
Jul 9, 2009
8,325
670
113
northeastern Minnesota
I was joking. Didn't know they could get too much air. And I have no idea how many holes I punched. Close to a half bazillion. I figure that when I have it on the bike I'll try running the motor with the lid off, in other words with unrestricted air and see if there's any difference. I bet not. I think as long as they get enough all is well. On the other hand, I don't know much about motors except that I like 'em.
SB
 

Dan

Staff
May 25, 2008
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Hard to see in your pics but counted 1/4 of a bazillian holes at best. That was my thinking, give em more air and fuel to make up for the extra 1,200 RPM. Tomorrow gonna try her with removing brass horizontal jet, when that fails, gonna try just making it bigger. This poor engine. Soon to try losing the spacer. Have to redo my throttle first. Didn't mean to ramble on your thread. Your air filter is very cool and opened some thoughts
 
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silverbear

The Boy Who Never Grew Up
Jul 9, 2009
8,325
670
113
northeastern Minnesota
OK then, give or take a quarter bazillion holes. I still need to disconnect the governor and then figure out how to run the throttle... connecting it up at the engine. That little gas tank that came on it is kind of nice. It would make a neat little auxiliary tank behind the seat for extra range. I'm pretty impressed with this motor so far, especially for $81.75, make that $86.75 with the upgrade air filter. Tomorrow I want to work on the engine mount. Got my hockey pucks and sure hope this mount idea actually works. Some ideas are good. Some aren't so good. We'll see which is which. Good luck with your modifications. Yes, poor little abused motor... you should be ashamed, Dan.
SB
 

Dan

Staff
May 25, 2008
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OH! I meant to take pics for ya Tin. I used the small black spring (from the gov) and a screen door wheel. Wrapped the cable around and stopped it with a wirestop. Used an old spoke for an arm to operate the butterfly. Could just back spring with a small angle shaped bit of metal. As soon as I lose the fly-wheel shroud, is what I am doing.
Anyway, spring from inboard. cable from forward and back locked to carb.

Ayup, needs pics but works great. Even with the cost of the screen door roller, cost less then a buck.

Save the gov parts! Got a bunch of them cool tanks in a draw. Would make great aux tanks. Way nicer then a pea tank. Just so dang small
 

silverbear

The Boy Who Never Grew Up
Jul 9, 2009
8,325
670
113
northeastern Minnesota
OH! I meant to take pics for ya Tin. I used the small black spring (from the gov) and a screen door wheel. Wrapped the cable around and stopped it with a wirestop. Used an old spoke for an arm to operate the butterfly. Could just back spring with a small angle shaped bit of metal. As soon as I lose the fly-wheel shroud, is what I am doing.
Anyway, spring from inboard. cable from forward and back locked to carb.

Ayup, needs pics but works great. Even with the cost of the screen door roller, cost less then a buck.

Save the gov parts! Got a bunch of them cool tanks in a draw. Would make great aux tanks. Way nicer then a pea tank. Just so dang small
Yeah, I'd do better seeing a picture. The tanks... do you know if they leak at the cap? If they don't leak then there is a third of a gallon sitting there. With the peanut tanks you can only fill them half way anyway or they leak out the cap. The cap seems to shut down tight, must be vented. If it doesn't leak that would be cool. Good to know if they're usable or not. It would be a comfort to know you had spare gas in case you ran out on the main tank. It has a nice low profile and would tuck nicely behind and kind of under the seat on a rear rack. I think I'm going to watch the HF sales and pick up another motor to have on hand. Why rebuild one when it wears out if you can replace it for $80.00? Elmo said something about adjusting the valves for better power. Is there a thread on how to do that? What is a good spark plug?
SB
 

Fossil

New Member
Mar 15, 2008
228
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0
Guthriesville Pa
Very cool silverbear. Looking at your picture I see something else you can do. Unbolt and rotate the recoil starter one hole counterclockwise. That will put the handle straight up so you will be able to easily start it while sitting on the bike.

Jim
 
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silverbear

The Boy Who Never Grew Up
Jul 9, 2009
8,325
670
113
northeastern Minnesota
Very cool silverbear. Looking at your picture I see something else you can do. Unbolt and rotate the recoil starter one hole counterclockwise. That will put the handle straight up so you will be able to easily start it while sitting on the bike.

Jim
Yes, I was noticing yesterday that the way it is you'd need to be on the right hand side of the bike and forward to start it and today staring at it realized the pull start could be rotated one bolt worth if the bolt holes were all the same distance apart. So they are then. That's good to know. Kind of a cool motor, I think. I was reading over the whole thread of yours and Chris's on the Greyhound Corvette build and was glad to read about the low end grunt power. I'm more interested in that than top end speed. I want to just walk right up those hills even if it is at a very modest speed... so long as I'm not pedaling or getting off to walk up the hill with it next to me then I'm happy. I'm running a 65 Tooth driven sprocket and will later get that adjustable pulley. This is a harder installation than the HS on the straight bar Schwinn, but I think it is going to be a cool ride, especially if it climbs those hills in the mountains of Maryland. If it can do that then it won't have any trouble pulling a canoe sidecar along here in Minnesota. I'm looking forward to it. Tomorrow I fool with the mount. Hope what I have in mind works. Sure do like these four strokes.
SB
 

Elmo

New Member
Sep 3, 2009
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Mississippi
I like it! Looking forward to your final pics "Silver bear, AKA Tin Snips, PI"

Is on the list of "how can I mess with the HF any more" but have you tried removing the spacer between the engine and carb? Would give lots of room. I am gonna lose the large shroud and was wondering if that spacer would have an effect.

Any way, as always, looking good SB! err, I mean Mr Snips.
Dan IHMO that spacer is beneficial because it insulates the carb from engine heat and provides a minuscule amount of ram effect. The spacer is one of the tricks the gocart folks use to get more power.
 

Elmo

New Member
Sep 3, 2009
748
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0
Mississippi
That is a very nice looking air cleaner SB. The stuff you are using for a filter should work very well. You sure have some good ideas on making stuff.
 

Elmo

New Member
Sep 3, 2009
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Mississippi
hmmm, could it be cut in half with no ill effects?

What is ram effect? would this effect our small engines? Ram-air intake - Wikipedia, the free encyclopedia
Yeah cutting it in half ought to be o.k. these little engines don't get too hot anyway. I rode mine almost nonstop for 100 miles averaging 27.5 mph and it wasn't too hot to touch the valve cover.
Sorry SilverBear I am not trying to hijack your thread. Any further comments will be on topic.
 

Dan

Staff
May 25, 2008
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it places the engine out a good bit. if those inches could be shaved off, could add a lot to a beefy tranny on the left side.
 

Dan

Staff
May 25, 2008
12,765
115
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Moosylvania
If we stop rambling on each other's threads, we would just be elsewhere rambling on some one else's. lol

Sorry Tin, I will stop. Rubbin' Loven to Moosh