Lawnmower cowling on the 4 stroke motors

GoldenMotor.com

Maxvision

New Member
Jun 13, 2009
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San Diego, CA
Has anyone figured out how to do away with the lawnmower cover on the right side of the 4 stroke motors? I'd like the give the 4 strokes a shot and get one but that cowling is just so gawd awful ugly.
 

Bikeguy Joe

Godfather of Motorized Bicycles
Jan 8, 2008
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Yes, start them up by a fan and get going, never stop until you are ready to shut it down. The shroud directs the cooling fan air over the cylinder, it's needed.
 

ocscully

New Member
Jan 6, 2008
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Orange County, CA
Has anyone figured out how to do away with the lawnmower cover on the right side of the 4 stroke motors? I'd like the give the 4 strokes a shot and get one but that cowling is just so gawd awful ugly.
I've been curious about this myself. I've never seen any empirical data/temp. posted on either site. There are statements and stories about "my friend burned a valve or destroyed his motor" etc. but I've never read or seen a first hand report from someone who has suffered any damage. There is a builder in your area (San Diego) who has a streached chopper cruiser with a Honda GXH50 with no shrouding and he seems perfectly happy with how it performs. There is a builder in Detroit that has a HS motor in a new build using the SBP 4-stroke shift kit that has no shrouding and so far he has not reported any problems running his bike this way. Harbor Freight has a coupon for their $60.00 laser Thermometer offering 56% off (selling price $26.99) I've been thinking about buying one and running my own test to see just how much difference there is with and with out the shrouding.

ocscully
 
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azbill

Active Member
May 18, 2008
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Fountain Hills, Arizona
Scully, if you do the temp test, please let us know your results...
I have seen zombie's build (in SD), but he said he only does short, pleasure rides,,,

I removed my shroud to check out the look, but re-installed it due to not wanting any valve damage (it gets really hot here [120+])

they DO look much nicer without the shroud :)
 

jcchappy

New Member
Aug 18, 2009
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antlers, ok.
air cooled motorcycles have never had shrouds or fans and they work fine. speed you say. dirt bikes can be used trail riding at slow speeds and they don't get hot enough to hurt anything.
 

Maxvision

New Member
Jun 13, 2009
551
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San Diego, CA
Ah yes, MUCH nicer look with the cowling removed.

I'm still not crazy about the pull start showing but with a centrifical clutch I guess it's necessary. I'm sure one day someone will come up with something to replace it (ie. electric start)
 

GearNut

Active Member
Aug 19, 2009
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San Diego, Kaliforgnia
air cooled motorcycles have never had shrouds or fans and they work fine. speed you say. dirt bikes can be used trail riding at slow speeds and they don't get hot enough to hurt anything.
Motorcycle engines also have longer cooling fins to allow that.
A forced air cooling system generally has shorter fins to make the whole assembly more compact.
They are matched to the task required.
 

Bikeguy Joe

Godfather of Motorized Bicycles
Jan 8, 2008
11,837
252
63
up north now
air cooled motorcycles have never had shrouds or fans and they work fine. speed you say. dirt bikes can be used trail riding at slow speeds and they don't get hot enough to hurt anything.

That's because they were designed to run without a fan or shroud.

The old Harley flat head engined Servi-Cars were designed to idle all day long with no air moving over them. These little air/fan cooled engines may suffer damage without the shroud....anybody want to try and let us know what happens?
 

azbill

Active Member
May 18, 2008
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Fountain Hills, Arizona
as much as I dig the raw fins look,,,
I can't afford to be the guinee pig on this one,,,
the 120 weather will be here soon and I depend on my bike/taxi too much
(5100+ miles on my engine :))
I took the exhaust shield off for a couple of days last year,
then got nervous at lights and stuff (idling), so I put it back on
 

[email protected]

New Member
Sep 25, 2009
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San Diego
I agree that the shrouds are ugly... that’s why i just painted mine black with some Krylon Fusion (thank you bill)... It’s insane!.... check out broped.... they have a few pictures up with black shrouds.... I’m sure you can agree a black bike with a black shroud is pretty sick!
 

[email protected]

New Member
Sep 25, 2009
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San Diego
Also.... if you are debating on whether or not to get a 4 stroke because of their looks.... RIDE ONE!.... i wasn’t too pumped on the red shroud... but after riding my first 4G.... I’d ride it if the thing was pink
 

azbill

Active Member
May 18, 2008
3,358
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38
64
Fountain Hills, Arizona
are we discussing the pull start cover or the metal shroud over the fins ???
I do agree that painting the pullstart cover is a big plus ;) (I used fusion on mine as well :))
 

Dan

Staff
May 25, 2008
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Moosylvania
I have run em with and with out and have had no problems. I actually put mine back on this winter to try and warm the engine.

I will take a ride today with and with out and take temps. But it is on a HF 79cc. I was told that it would hurt a Honda/HS engine. I have a Honda engine but is a project way back in line. That and I ran out of bicycles, snork. Kinda cool. Been so busy, just do not get to ride any more. But this is for "research" lol, the wife just nods grinning and says, "uh-huh"
 
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