Carb Anti Icing ideas

[koko64]

Nate. Just did a simple "test".

I ran the bike at idle from cold in the shed and monitored the manifold temp. Gave the bike 5 minutes running at idle and fast idle, and the manifolds became hot except for the top 3/4 of an inch. The area is at the first bend just before the carbs and the longer radius side was closer to an inch of cold material, the shorter inner radius more like 1/2 an inch. That would be where the cold charge was hitting the radius. The manifolds became hot as the heat worked its way up their length over time. Of course as soon as I turned the motor off the whole length of the manifolds became too hot to touch very quickly, including the spigot rubber's retaining clamps.
It certainly demonstrates the force of the venturi effect.

I remember years ago that stopping and letting the bike idle awhile defrosted the inlet tract. I would ride off and the bike would run fine for a few miles until it would start freezing again. The more I think about it the more I keep coming back to using the existing heat source rather than adding one.

[ducpainter]

A fast idle would sort of simulate a cruise scenario...at about half speed.

It might work. Like you say for the $40 bucks it's worth a try.

[ducatiz]

Here's a good idea.. trap the heat with a "controlled air flow"

[koko64]

 

[Howie]

Like you said, trial and error.  Maybe temporarily mounting some sort of temperature sensor  to make sure you don't over do it.

[koko64]

Rapped the manifolds with carbon coloured wrap from where they bolt to the head right up to over the spigot rubbers up against the carb bodies.
Will ride to work today with the temps ranging from 5-13C out here with high humidity plus added wind chill factor. Should be good for icing.
I'll give the bike a good 5 minute warm up and see how she goes.

[koko64]

First impressions.
The ride home tonight was very cold and I could feel the bike running well, better than it could have. It seems as if the wraps have helped to a degree but that more severe conditions could pose problems. Ill keep riding the bike over the winter to find out.

The float bowls were cool to cold to the touch but not very cold. Surprisingly, the throttle shaft caps were tepid to lightly warm to the touch. The insulating properties of the wrap appear excellent, you can hold the manifolds at idle and feel no heat coming through. Maybe some heat is working its way up there.
Nibor is lending me a  temp tester for real data.

[koko64]

Rode the bike all day today. It was bloody cold this morning with up to 87% relative humidity. I could feel the bike trying to ice up at times, but once warm it was fine. The odd falter but no stalling kind of thing. It occurred when rolling off and the CV effect was high, there would be a pause when rolling back on, but that's all.

That about wraps it up. A good warm up is important to have any effect, and no doubt in extreme conditions the wraps only help a little. There's just too many ways for ice to form in the intake system and the wraps only help with one of them. I think they will mitigate carb icing, but not eliminate it. Oh well, it's something I 'spose.

[ducpainter]

Did you also block the oil cooler?

[koko64]

I didnt even think of it, just the manifold wrap. Good idea, no reason I couldnt wrap the cooler.

[ducpainter]

I didnt even think of it, just the manifold wrap. Good idea, no reason I couldnt wrap the cooler.

If your bike has cylinders with an oil jacket it will help retain heat even more. My '96 will still have condensation in the oil after a long ride at 40F ambient.

I've used duct tape, but had some adhesive transfer. You need something you can pull off if the day suddenly warms up.

[koko64]

It's an effective system alright. The Paris/Dakar bikes proved that.

 I'll rig something up and try it. I see  wrap and cable ties.

[Howie]

On the old bike I used Naugahyde held in place with wire ties I could easily cut on an unusually warm day.  Helped a bit.  The new old bike has an oil cooler guard that should make the task easier.  Shame Ducati doesn't run a thermostat for the cooler.

[ducpainter]

On the old bike I used Naugahyde held in place with wire ties I could easily cut on an unusually warm day.  Helped a bit.  The new old bike has an oil cooler guard that should make the task easier.  Shame Ducati doesn't run a thermostat for the cooler.

There was an aftermarket one available from the same guys that made the slave pistons...Evoluzione I believe. Eric didn't like them because they reduced flow even when fully open.

[koko64]

Had a cover that velcroed onto my Harely oil cooler. My upholsterer could make a nice one lined with exhaust wrap. Hmmm.