Carb Anti Icing ideas

[Howie]

I think you have it right on why the needles freeze on the Mikunis Tony.  As I remember, freezing on Monsters was a big problem in England, first came the oil heat kits, then came the factory electric bowl heaters.  My memory is questionable though.  All carburetors are subject to freezing.  Common on cars was running either exhaust gas or coolant under the carb to help with both freezing and atomization of fuel when cold.  Later, more for emissions, came the thermostatic air cleaner too.  You are probably correct about the long manofoplds since they create a higher velocity at cruising speed. 

[koko64]

I'm feeling even more confident about the manifold wrap/carb sock option actually working after taking the Monster out for a run tonite. It was cold and misty with a frosty feel to the air around these parts and a little carb freezing occurred. 

Went for a good 30-40 minute ride and when I returned home I could hold the manifolds even though the motor was quite hot. The manifolds were quite cool for 3/4 of their length and only a little warm near the heads, but when I touched them again after 5 minutes of the bike sitting I could barley touch them they were so hot. I had forgotten about the heat saturation that works its way into the manifolds once the bike is parked.

The wraps should protect the manifolds from the external cooling effects of wind chill and allow internal heat saturation to occur from engine heat. If the manifolds could be that hot while the bike is running then surely that is a hell of a lot hotter than the oem oil jacket and wimpy electric element solutions. The best source of heat available for the inlet tract is from the heads.

[ducpainter]

I understand what you're trying to accomplish, but I'm having some difficulty understanding how insulation alone will counter the venturi effects of the volume of air in the manifolds and allow heat from the heads to soak into the manifolds while it's running.

[koko64]

The objective is any icing upstream will disappear downstream if its hot enough there in the manifolds. Theres nothing to do about the venturi effect bar changing carbs or using short manifolds I guess. Im just hoping to add heat. It will be more heat than the other methods.

[ducatiz]

I think oil is the best way to heat things.  What about putting a very small oil cooler between the manifolds? 

They make some very tiny coolers for go cart racing..

[koko64]

I understand what you're trying to accomplish, but I'm having some difficulty understanding how insulation alone will counter the venturi effects of the volume of air in the manifolds and allow heat from the heads to soak into the manifolds while it's running.

I wasnt very clear. The test was with no wraps and showed how much lost heat is available if the manifolds arent cooled by the wind. They got very hot once the bike was off and parked. My aim is to have the manifolds no longer subject to the air cooling and hot enough to be a counter measure to the venturi effect.

[ducatiz]

I wasnt very clear. The test was with no wraps and showed how much lost heat is available if the manifolds arent cooled by the wind. They got very hot once the bike was off and parked. My aim is to have the manifolds no longer subject to the air cooling and hot enough to be a counter measure to the venturi effect.

That makes sense since you would be drawing heat from the head and if they are covered will prevent air from pulling the heat off...  Interesting.

[ducpainter]

I wasnt very clear. The test was with no wraps and showed how much lost heat is available if the manifolds arent cooled by the wind. They got very hot once the bike was off and parked. My aim is to have the manifolds no longer subject to the air cooling and hot enough to be a counter measure to the venturi effect.

I'd be more convinced with a running but not moving test...like on a dyno.

[koko64]

I'll try with the wraps when they arrive and check the manifold temp after a ride. You reckon the internal cooling of the venturi effect will be too much for the heat from the head to work? Much of this solution comes from the manifolds being aluminium which also contributes the problem. The heat really transferred down the manifolds so I'm hopeful.

I think oil is the best way to heat things.  What about putting a very small oil cooler between the manifolds? 

They make some very tiny coolers for go cart racing..

G'day Tiz
Anything to do with oil plumbing was my last option after the factory oil heater. You mean aim the little cooler at the bowls? I reckon any oil based solution would need the OEM oil cooler covered over, since it works so well.
Yeah, I want to keep the heat there and not let it dissipate. The alloy manifolds just transfer heat very well so I gotta turn it to our advantage.

[ducpainter]

I'll try with the wraps when they arrive and check the manifold temp after a ride. You reckon the internal cooling of the venturi effect will be too much for the heat from the head to work? Much of this solution comes from the manifolds being aluminium which also contributes the problem. The heat really transferred down the manifolds so I'm hopeful.

I'm not sure Tony. Undoubtedly removing the effect from the outside cooling will help slow down the heat loss in the manifold. I'm just not sure enough heat will be retained to keep the needle from freezing.

I'm really hoping it will, I'm just having a hard time wrapping my head around it because I can't fathom the numbers.

[koko64]

Nate, it's all uneducated guesswork over here.
I doubt the heat will do much that far up the inlet tract, but I think manifold freezing is more the problem on this model bike. I have seen a coating of ice on the outside of manifolds. Amazing.
I reckon bikes with ram air like the ZXR 900 get freezing at the carb bell mouth and needle, etc. The M900 gets all the air velocity down the long manifolds. Again I'm guessin'

[ducatiz]

G'day Tiz
Anything to do with oil plumbing was my last option after the factory oil heater. You mean aim the little cooler at the bowls? I reckon any oil based solution would need the oil cooler covered over, since it works so well.
Yeah, I want to keep the heat there and not let it dissipate. The alloy manifolds just transfer heat very well so I gotta turn it to our advantage.

i think you could get creating with (say) copper piping.  maybe wrap the manifolds in it, multiple coils around using 5mm ID copper piping and then use the oil heaters for the carbs as well -- run the oil thru the coils and then thru the carbs heaters. 

does that make sense?  You'd use the factory carb heaters (oil) but would plumb them off a custom copper coil you fabricated around the manifolds.

cluster-F no doubt..

[koko64]

I understand. Might work too, but what a mess

I'm gonna try $40 exhaust wrap first and some wire/cable ties.

[Howie]

Maybe some of this stuff under the wrap?

http://www.heatingelementsplus.com/12-24-volt-self-regulating-cable-c-1_272.html

[koko64]

Thanks Howie.

That stuff might also let me make a float bowl or carb body heater. The recessed holes for the elements and banjo fittings might allow a place for hose to be fitted in either the bowls or carb bodies. What do you think?