Case of the missing shroud...

I've only had my 4 stroke HS engine for a few weeks and really like just about everything about it... except for that orange/red plastic shroud. Man, that is uuuuglyyy. I see that some have painted them black and have been told others have painted them silver. Much better, the painted ones I've seen, but still. That's where the 2 strokes have it all over the HS, the Honda it was cloned from and the HF engines. The Happy Time engines just look good. Like a little motorcycle engine... all business, all engine and fits right in the frame because that's what it was designed for, a bicycle. The 4 strokes mentioned were designed for other uses, as industrial type motors for stationary applications. So they don't tuck down low into the frame and with the plastic shrouds they look kinda clunky to my eye. Don't get me wrong, I love the way my engine runs and it is a big improvement, a step up from my experience with 2 strokes. I just wish they looked better.
So, my question is what is that plastic shroud for? And all the heat shields, what's that all about? I have seen a couple of folks here have removed the shrouds or at least talked about it. Several days ago I removed mine and ran a few days with it like that, no great distance, but to my eye it looked a whole lot better. I did get a wee bit nervous about the flywheel being exposed in that something could get caught in it. Talk about getting your pants in a bundle, well that would do it if they somehow got caught, or a skirt on a lady, a coattail maybe. So, I did some thinking, the light bulb in my b.b. brain lit up and I got an idea. The end result of my fabrication is pictured below. Whether this turns out to be a good idea or a wrong turn in the road I'll detail how I made in the ezmotor build competition which I have entered. When I get to that part I'll show detailed photos of how it was made. But that's later. Here's the question. Is it a bad idea, removing the shroud? I had thought that it was there mostly for protecting an owner from the flywheel. But a friend whose opinion I value highly has advised me to put the shroud back on as it is necessary for the proper cooling of the engine. The flywheel has fins which direct the air flow upwards against the fins in the head. That made some sense to me and I thought about all the work that went into my spiffy custom flywheel shroud,apparently a wrong turn in my Motorbike build. Back to the drawing board.
But is it? The HS motor was designed for stationary running. On a bike it is outdoors and is moving through the air, so it seems to me that is a very different situation from a stationary motor that might be sitting in a hot environment with little air exchange. And if it is so important to cool those fins above then what's the deal with all those heat shrouds? Doesn't that keep the heat in? Are they there to keep you from burning you fingers or something? Most of the time I will ride my bike it will be in the cool to cold of northern Minnesota, and never in the desert of Arizona in July. It seems to me that if the heat shrouds were also removed (making it look better, too,) it would improve the cooling.
All that being said, I know next to nothing about these motors. I'm just guessing and surely do not want to wreck my motor. So, who has an opinion on this? I'd appreciate knowing more than I do and of course hope I can keep my custom flywheel shroud because I want my bike to look as good as it sounds and runs. Three photos show my bike with the shroud, with no shroud, and with my little flywheel shroud. Many thanks,
SB

The sheet metal is still on because I haven't removed it yet. I just got the bike together about a week ago. The gearbox cover bothers me a little less because at least I know it is there for a reason. I'm thinking about it. It isn't a simple thing for me to make a different cover and I know that no matter what, it needs a cover. I know other systems have a smaller gearbox, but I like the mechanics of this one, which is why I have it. First comes the way it works and second the way it looks. Give me a little time and maybe I'll think of something within my abilities to make. I don't weld and I'm not a machinist. This thread was not about the gearbox, it is about the shroud and the heat shields and posed the question of whether or not they need to be there, regardless of the transmission system being used. A lot of us are using this motor. You sound kind of ticked off. Am I missing something here?
SB

azbill said:

I think it looks much better

I was warned though, when I was first researching the 4cycle engines, to keep the metal on, as it directs the air flow from the flywheel over the cooling fins

I took mine off just to see what it looked like (much nicer, btw)
but, I got paranoid about burning a valve

it is a little cooler where you are, than the desert here, and you don't have the stop n go traffic of a city, so I think it should be good

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Thanks for your opinion, Bill. Do you have any idea how big a job it is to replace the valves if they did burn? If it is not too big a deal, maybe I'll leave this as it is to see how long it will go and if the shroud is really necessary. Do you see any reason not to remove the heat shields? It would look nicer without them and my thinking is it might make the engine run a little cooler. No, I don't ride in city traffic with stop and go and rarely need to stop even for a stop sign. Most of my riding is go go go. I think the HS is a nice engine, very smooth running, so I imagine the Honda is, too. The four strokes are just different, I guess. This is all new to me. This winter I'm going to try a build with the HF Greyhound to see what that's about.
SB

I appreciate the feedback, you guys. Sometime I'll get the heat shields off, too, but imagine that as tight as everything is in my frame that I'll need to pull the motor, so will probably wait until the riding season is done. I also want to get a nicer looking air filter when I can afford it. Evey little bit helps.
Scotto... wrong! Not a coffee can! Same size can, though. I found a humongous can of tomato sauce for $4.40 cents at the grocery in town, so that yields two fin shrouds at $2.20 each... a better deal. I'll use the tomato sauce in my gourmet cooking here at the Road Kill Cafe, so the shrouds are cheaper yet. I'm going to just leave that one on to see how it holds up to time and weather. If it starts rusting, I'll pull it and use it as a pattern for the new and improved fin cover and maybe give it clear coat as a protection. As I recall, Baridco said something about a clear coat for mag wheels that is really durable stuff. Maybe that. Or I could paint it black. But the little kid in me likes shiny on an engine best. It took me a good while to carve away at it with the dremel tool to get a nice fit. If you make one, be sure to check that it has clearance from the flywheel before trying to start the motor. I had to use a couple of little washers, but once in place it is very secure. I'll put the step by step photos in my build thread pretty soon, although you can figure it out on your own, I'm sure.
SB

MotoMagz said:

I like the tomato can shroud I'm going to borrow that idea.I think it really depends on the weather in your area if you can take all of these cooling shrouds off.Put if your running a temp gauge...your good.

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Thank you, Sir. It was your bike that got me wanting to remove the shroud on mine. When I first saw it I didn't even recognize them being the same motors. What a difference! Temperature gauge? Could I have a temp gauge permanently in place? Ooh gauges... like Scottos tachometer. Tach, speedometer, temperature gauge. Wind, air temperature, barometric pressure, altitude. The little boy in me likes shiny and gauges, both. The horizon of possibilities has just broadened...
SB

I think what those fins weigh is not very much, especially when you consider what the Whizzer front fork must weigh (a lot), stainless steel gas tank, heavy old Schwinn frame and heavy duty wheels, plus pulling the dog in a trailer and a having an old circus bear sitting on the bike... whew, what a load! I doubt the little bit of weight shaved off would help much in my case. Ha! Besides, I'm pretty happy with the way the bike pulls along and don't want to go any faster than it already goes. For a young speedster maybe shaving off the fins is a good idea. I don't know. Sounds like a lot of work, too. They're out of sight now, so also out of mind.
SB