Author Topic: Vent flaps for engine heat (Read 15004 times)

Gusto · « **Reply #50 on:** March 28, 2018, 02:09:02 am »

Dave thanks for all your research on all this stuff. It gets real hot here in Texas and I’m going to make my flaps soon. I wore ankle socks with my riding pants on a warm day and the hot air burned my left leg pretty good. Painful and red. Full length socks fixed the issue for now but it’s not July yet!!

DaveSz · « **Reply #51 on:** March 28, 2018, 09:36:43 pm »

For anybody having trouble keeping their top heat shield in place, I find it easy enough to check by just reaching in between the forks. And easy enough to fasten in place with a wire tie on each corner. Through the square holes in the top heat shield, and around the tabs and screws of the rad's protective screen. Seems to be holding fine. See photo of left side wire tie, on my Connie. Camera held just between the forks for the photo.

Dave

Bob_C_CT · « **Reply #52 on:** March 29, 2018, 12:33:16 am »

Good idea DaveSz. Looking at your photo that wire loom behind the radiator screw seems like one of those wires are getting chaffed. I gotta make me a pair of those shields for the warmer weather. Thanks for all the research that went into the design.

DaveSz · « **Reply #53 on:** March 29, 2018, 11:54:36 am »

Thanks, Bob. The wiring isn't so tidy, but has a bunch of that "liquid tape" on it, so should be OK. But not pretty. I recently soldered in a temp sensor bypass switch on the radiator fan, so I could try a bit of "manual fan" when I'm caught in traffic. Was reading about the "BMW Johnny Blanket", mentioned by Jacksdad, and one of the BMW guys on their forum mentioned using a manual fan switch in traffic. Just thought I'd try it on Connie, when we finally get some heat this summer. The vent flaps work pretty well when riding, but sitting and cooking in traffic is still an issue.

Dave

connie_rider · « **Reply #54 on:** March 29, 2018, 01:04:12 pm »

Be carful with your fan bypass switch.
Leaving it on accidentally {when you get off the bike}, will quickly drain the battery.
{Don't ask me how know this

}

Ride safe, Ted

DaveSz · « **Reply #55 on:** March 30, 2018, 01:04:59 am »

Hi Ted,

The fan is on a 10 amp fuse on my Connie. Was curious about the amps pulled, so tried a 5 amp fuse. Blew in 5 seconds. So somewhere between 6 and 9 amps? Don't have a suitable meter for DC amps handy. But for sure don't want to leave it on! Fortunately, had a left-over switch with indicator light in my electrical junk drawer, and it is bright enough to be seen in daylight. Also was tempted by a spare turn signal beeper, but I'm making too much noise as it is!

The BMW guys thought running the fan on manual was some help with heat when in traffic. What do you think for the Connie?

Dave

connie_rider · « **Reply #56 on:** March 31, 2018, 08:57:10 am »

It kept the engine cooler.
One drawback; It also {continuously} blows heat back on your leg.

In Houston stop and go,,, arghhhhhhhhh!!

Ride safe, Ted

DaveSz · « **Reply #57 on:** April 16, 2018, 12:55:16 am »

We finally had three warm days (70+ degF) to ride this week. Screaming winds, but still much appreciated. I wanted to measure the oil temps with/without the vent flaps. Had gotten 160 degF sight glass/170 bottom of pan when riding without vent flaps on 40 degF ambient days. Cooler than I expected.

With the ambient at 70 - 75 degF, and no vent flaps, and checking after 20 miles at motorway speed, I had 190/200 degF (sight glass/bottom of pan) with the laser infrared temp sensor. And for sure, hot legs.

Then with the vent flaps on, and the same ambient temps, I found the engine oil temps to be lower after riding 20 miles. 180/190. And for sure, I had cooler legs.

But when I rode on to the next rest stop on the motorway, cool and comfortable with the vent flaps still on, and checked again, the oil temperatures had eventually risen to 190/200 degF. Took a little longer to heat up, but as far as I can measure with the hand held sensor, the oil temp with vent flaps on ends up reaching the same temperature (as without vent flaps) after 40 miles at speed.

Did several checks this week, with some small variation, but effectively the same results. Will make another comparison when the temps get up in the 80s. Am curious how hot the oil gets on Connie.

Am thinking how to put a more accurate digital oil temp sensor on Connie full time. Anyone do that? So far, the only idea I've had is to drill out one of the oil drain plugs, and solder in an RTD temp sensor with digital display. Suggestions? Would be better than just the radiator temp for judging winter warmups!

Dave

DaveSz · « **Reply #58 on:** June 21, 2018, 10:48:09 pm »

Been enjoying the summer, and riding whenever possible. Now with the added manual fan switch, I'm just flipping it on coming into traffic situations. Better. Still thinking about her heat though, and learning.

Have added 3 K-thermocouples w/ red LED displays. One on her chin, just under the headlight, for measuring ambient air temp. Another about 1 inch above No. 3 carb, for air temp under the tank. And the third is installed in the front oil drain plug, for measuring oil temp. The oil plug is overall 25 mm long, and I drilled a 23 mm deep hole in it, and tapped it for the thermocouple threads. Displays in degC. $5 each. Photos attached.

Also added an automotive temp sensor to the thermostat housing, to monitor the water temp leaving the engine. It is a routine sort of 1/8 NPT sensor, with a blue LED display. Sold for use in water or oil. $13. A better tool for this business, as it can easily be seen in daylight, and reads in degF. Chose to remove the allen socket drain plug on the thermostat housing and tap and install the sensor there. Fits nicely just below the thermostat that way, in its drain channel. Put 2K miles on her with it installed, and no leak or anything. Yet....

With the temp sensors all hooked up and measuring, I've been watching and comparing the new digital temp gauges with the original "vague" factory temp gauge. Some observations......

- On a 74 degF morning, the thermostat temp climbs to 175 degF and levels out after only 3 or 4 miles. It stays near 175 degF after 40 miles on the freeway at 70 mph. The oil temp will slowly climb to 165 degF after 15 miles, and will gradually ease up to 170 degF by the 40 mile mark.

- With 175 degF showing on the new blue digital thermostat display, the original factory temp gauge is pointing just at the right side of the "square" above the C. Can reasonably think of the left side scale (C) of the original engine temp gauge as starting at just 160 degF (and straight up as 212 degF) on my Connie.

- When I slow down and exit the freeway with the rad fan turned on manually, the thermostat temp goes up to 185 degF after two traffic lights, and the original temp gauge pointer just moves 2 or 3 mm hotter. Oil temp goes up slower, but goes up about 10 degF also.

- When I slow down and exit the freeway with the rad fan off , and being controlled by the auto fan switch, in two traffic lights the pointer has moved to the middle, the thermostat temp has risen to 212 degF, and the fan kicks on automatically at that temp. Oil temp heating up slower, but along with the thermostat temp. The thermostat temp overshoots the 212 degF setpoint of the switch, up to 218 degF. By the third traffic light, the temps are creeping down slowly, but not enough to turn off the fan in slow traffic. Fan goes off once above 25 mph, and entering the freeway, and after 4 or 5 miles, she settles back at 175 degF on the new blue digital thermostat temp display.

- With vent flaps on, and the rad opening closed, the temp above the carbs was just 10 - 12 degF above ambient, while at freeway speed. Legs comfortable.

Installing a 50 amp shunt next, to verify the amperage used. Interested in total output amps of alternator, with/without rad fan, etc..

Ordered a new cap for the radiator. Is blowing out the cap a bit, when temp above 212 degF today. With 13 psig cap, shouldn't be.

DaveSz

Lee · « **Reply #59 on:** June 29, 2018, 12:36:27 am »

Thanks for all this work up! Watching closely as it goes. Good information to have!

connie_rider · « **Reply #60 on:** June 29, 2018, 02:04:17 pm »

Over the years some have moved the coolant reservoir to try to increase cool air flowing past the engine.
Would you gages show if this works or not?

Ride safe, Ted

crag antler · « **Reply #61 on:** June 29, 2018, 09:02:37 pm »

I've been following this as with summer here in the White Mountains, it is warming up.
Going to be hotter here than where I moved from in Florida. 95 vs. mid 80's.

Thought I didn't have the radiator cover so ordered one from eBay.
Low and behold when I had her apart for the Murphs headlight harness, I found mine.
It had slid back. Snapped it back on and have to see the difference.
Anyone needs the cover, its yours for shipping.

Great idea with the wings.

DaveSz · « **Reply #62 on:** June 30, 2018, 03:34:01 am »

Warming up today. Was out on the freeway in the afternoon, with ambient bumping 90 degF. The digital thermostat temp settled at 180 degF, after a few miles at 70 mph. (It had settled at 175 degF, on a 74 degF day.) Carb area air temp at +10 degF over ambient, at speed. Oil temps lagging the thermostat temps, and only 5 degF lower. When thermostat temp up, oil temp up a bit after. Thermostat temp down, oil temp gradually back down too, but slower. New digital thermostat temp is much more reactive, and interesting. And readable in bright sunlight.

Ted,

Not only is there a large opening between the stock Connie radiator, and the oil cooler, but there are openings low on the sides, and bottom of the fairing, to allow a LOT of air to BYPASS the radiator and oil cooler, and increase pressure and air flow between the rad and motor. But these openings reduce the air flow through the radiator and oil cooler, by decreasing the pressure drop across both. I'm thinking that relocating the coolant reservoir would just increase the amount of bypass air, and make the rad and oil cooler less effective. I'm riding with the vent flaps on, and the radiator gap closed to get more air through them, and less bypass air, and drawing the smaller volume of hotter air out the vents, away from the motor. Vent air is hot.

Will think about it some. Air temp rig is laying around somewhere. Do have some other tests in mind, and a just plain fun ride up to Lake Erie tomorrow. It's a 94 degF afternoon coming, and I wouldn't have thought of going out for the day, before putting the vent flaps on her. I don't do it often, but today I was wearing sandles while riding, instead of the boots. Ankles and feet were a bit above ambient, but comfortable, without the side scoops on.

Dave

connie_rider · « **Reply #63 on:** June 30, 2018, 05:04:07 pm »

Do have some other tests in mind,

I'm a retired research technician. So, I think of things as a comparison.
What I don't see in your testing is a baseline...
I would put the Vent Flaps back to stock {for a baseline} and compare those numbers with what you have now.
Perhaps you could do this halfway thru your ride to compare the numbers on the same day?

On the tank removal, the fan on my bike never comes on while cruising.
Only at lower speeds or stop/go traffic.

The only time I really notice heat on my legs is when the fan comes on and pulls air only thru the radiator..
Makes me think that the air that bypasses the radiator (and at the scoops) is mixing sufficiently to control temps at my legs.
Was just wondering if removing the tank, actually helped when cruising.
Your gauges might show any difference..

Ride safe, Ted

DaveSz · « **Reply #64 on:** July 02, 2018, 02:48:46 am »

Hi Ted,

Am planning to make another set of vent flaps for my Connie. Slightly larger, for hot days like yesterday. Or times when a crosswind pushes the vent air heat back on me. Will drag out my previous air temp sensors, and position them near my leg, for comparison. Will put her back in stock (OEM) for that also, as I did in February when testing the rad closure. This time with a good digital indication of the thermostat/engine temp, in each configuration.

While the air temps at key points can be measured for the different configurations, there will also be big differences in air flows, which will not be measured.

Will see how it goes, but can probably pull out the rad overflow tank, rig a temporary replacement, and make another run for that configuration. Will be a few weeks though, as I'm occupied with other stuff for now. And just riding when I can escape. Next escape is tomorrow at 07:00 hrs !!

Yesterday, rode up to Port Clinton and back, with ambient rising to 94 degF on the way back. Cruising at 70 mph, the thermostat sat right at 180 degF. As before, I usually flipped on the fan when coming down the exit ramp of the freeway, and kept it on in traffic. With 90+ degF ambient, and the fan on, she held at 195 degF or less on the thermostat housing, in slow traffic.

Dave

crag antler · « **Reply #65 on:** July 03, 2018, 07:32:07 pm »

Dave, it looks like your idea is coming along quite well.
If you ever have the desire, I would be up for purchasing a set for my '00.
Doug

DaveSz · « **Reply #66 on:** July 05, 2018, 03:30:32 pm »

Doug,

There's not much to making a pair of vent flaps. Yesterday bought a 12" x 24" sheet of 0.025" thick aluminum at Menards, the home improvement store, for $10. Very springy. Equivalent of T6 I'd say. Enough to make 2 sets of 11" x 4" flaps. Will use a fine hacksaw blade for most cuts, but also can cut it with the Dremel. Bending is in the vise, between two steel bars, but 2x4s would work.

I'm into my 3rd season now, with the 9" x 4". They are OK, but I just like to tinker, and try new stuff, so am interested in trying slightly larger ones. Let me know if you'd like a sketch with holes and bend lines, etc. Pleased to help.

I think a set made from ABS would be interesting, and not so difficult or expensive to make. More stylish or aerodynamic. Maybe somebody else will find it interesting, and make the effort. A vent flap mold is a bit beyond me at this point in life, but we'll see.

90% of installing the vent flaps is putting the blocks and T-nuts behind the side panels. Holes on mine are just over 6" apart, and both are 2" in front of the vent opening. Plenty of room behind the side panel at that location. See photo.

There's a photo of the blocks, slathered on with ABS pipe glue, and made from small chunks of ABS pipe, in the original post. I had some 1/4 -20 T-nuts hanging around, so I used them for the vent flaps, as I was impatient at the time. Would use M6 - 1 T-nuts if doing it today. Might change them someday to M6 - 1.

But as mentioned, I put my first ones on with 3M Extreme double stick rubber tape. Till I was satisfied with their performance. You could too. And then do the blocks/nuts when you have another reason to take the side panels off overnight.

Dave

oldsmoboat · « **Reply #67 on:** July 15, 2018, 12:40:37 am »

RE: Jim's wings

Help me understand this principle. The wings look like they would block ambient air from hitting your feet. Right now, that's how I cool them down by putting them in the air flow on my highway pegs that are mounted to my tip over bars.
How does blocking the air keep your feet and legs cooler?

DaveSz · « **Reply #68 on:** July 16, 2018, 10:23:39 pm »

Well, your feet are out on the highway pegs to cool them, because they are hot when resting on the stock pegs? Mine were. Really hot.

The wings (vent flaps) are working to pull the radiator air on out of the vents, so it misses your feet and legs. The vents don't work so well without them. The important point is that the wing provides a low pressure path for the hot air, so that it passes outward more easily behind the wing, and ending up an inch or two outboard of your legs, at about the level of your calf. Your feet and legs then stay cooler, when resting on the stock pegs. Mine now has slightly warmer than ambient air blowing on the stock pegs, and they are pretty comfortable.

However, if you really need to ride with your feet on the highway pegs to stretch your legs, then the wings might not work for you. Very hot air behind those wings. Maybe Jim will comment more about the highway pegs. I've no experience with them.

Dave

Jim · « **Reply #69 on:** July 22, 2018, 09:39:29 pm »

You do feel the heat around your ankle when using the highway pegs especially on the right foot. However, it's not uncomfortable with ankle high boots and socks and the blast of cool air running up you pants leg is worth it. Without the flaps, I remember the heat being higher towards my knee and thigh. I've done a lot of highway miles in the heat and cold with the flaps installed and the factory scoops installed (plugged with foam in the winter). They make the ride much more comfortable.

Charliedog · « **Reply #70 on:** July 22, 2018, 11:52:15 pm »

That looks like it would be a great idea. One thing I did not see mentioned: What is the angle of the flap relative to its mounting surface on the fairing?
In other words, how about a photo looking straight down the flap. TIA

DaveSz · « **Reply #71 on:** July 23, 2018, 11:40:58 am »

Right side, from above.

Dave

DaveSz · « **Reply #72 on:** October 14, 2018, 03:26:24 pm »

On an 87 degF day this past week, I dug out the stock side air scoops, and the temp rig for measuring the various temps, and got another set of data for Stock air scoops vs. vent flap setups. The vent flap setup also has the rad opening closed.

The digital thermostat housing temp sensor in the thermostat housing drain, is my best indicator of engine temp. But also have K thermocouple on the oil temp, and another thermocouple mounted above the carbs. See attached photo for positions of the side air temp sensors, that show the air temps on the inner side of my legs while riding.

The Thermostat housing temp for the two setups was the same, interestingly, and there was minimal difference in the oil temp. But the greater heat on my legs with the Stock setup was obvious, both in traffic and at speed. The volume of hot air coming out from under the tank is striking. And unpleasant. With my glove off, reaching into the carbs, you can easily feel the heat and air flow. There was also hot air from both side vents, trailing back along the fairing, and onto my shins and outer legs. The scoops kept my boots from cooking, but the heat on the legs above the boots is not comfortable.

With the vent flap and closed rad setup there is much less air flow from under the tank, and it seems not to come out from under the tank/carbs much at all. Most airflow around my legs was coming back to front behind the fairing. And though above ambient temperature, the air on my legs was tolerable. A non-issue, for riding in jeans on an 87 degF day. Carbs felt cool, as usual, reaching in without gloves.

Didn't get time to check with/without the rad reservoir. It is 42 degF this morning in central Ohio, so it will have to wait till Spring. I'm in winter mode now.

Dave

bajasam · « **Reply #73 on:** October 14, 2018, 09:35:56 pm »

Thx for all your hard work Dave.I made up a set from some .093 lexan from home depot and bonded them on with clear silicone . They work exactly as stated and I can comfortably ride in tennis shoes no socks and shorts except when sitting still in traffic.I was going to use some of that high tech thermo barrier on the bottom of my fuel tank but now that i've felt under there while riding I don't think there would really be any benefit to it.Thx Baja

DaveSz · « **Reply #74 on:** October 17, 2018, 12:13:03 am »

Thanks, Baja. Reading your post I was impressed by your clever use of clear silicone. Wish I'd thought of that! Would have been so much easier, and more frugal, than the double-side sticky tape I used on my various trial flaps. And easier to clean off after.

Just came in from a 200 mi ride. Was 55 degF when I left, and 49 degF when I got back. For days like this, I've been trialing a set of 11 x 2.5 inch winter flaps which give some wind and rain protection, but actually increase the heat on my legs vs. STOCK setup. When I was trying different size vent flaps, I noted that the 3" wide trial did pull the hot air out of the vent, but failed to pull it outboard far enough to miss me. My 11 x 2.5" flaps pull a lot of heat out of the vent, and it all just slides back along the fairing, warming me up. Maybe not a useful idea for the Southwest, but for winter riding in Ohio, not so bad!

Dave