Possible cooling solution: turbulating louvers alla V-Rod

[xxtraspec99]

Did anyone see the documentary on the Discovery Channel about the creation of the Harley V-Rod and the engineering hurdles that had to be overcome???

One major issue for the V-Rod was how to build an efficient radiator without making it monstrous looking. The issue for XX owners is how to make the XX's stock radiator better. The purpose of this post is to propose that the V-Rod's engineering solution may apply to increasing the efficiency of the XX radiator. Namely the use of turbulating louvers.

The Harley performance engineers (as distinguished from design engineers) had a problem creating an efficient radiator (the first ever time Harley was to use a radiator on a production bike).

From wind tunnel studies the engineers found that the front wheel and fender blocked a good portion of the incoming air. The design team vetoed using larger radiators or big scoops or outer fins to pull in air. So the performance engineers had the task of designing a smallish unit with capacity to cool a VR1000 race engine running at 10,000 rpms. The VR engine was the original proposal until Porche got involved.

Now this blockage of incoming air may also apply somewhat to the Blackbird. And there are enough similarities between the two bikes to warrant a further look. First, the horsepower and displacement of the XX and V-Rod are not too far apart. V-Rod is about 115 hp at the rear wheel and 1100 cc; while the stock XX is about 127 hp at the rear -- depending on model and emissions, etc. The redline of the two bikes is even closer.

In fact, given the sleek design of the XX front fender and fairing -- the result may well be that air is diverted from the radiator even more so than in the case of the V-Rod.

To make a long story short, through wind tunnel studies -- the Harley engineers found that the slip streams on the side of the bike acted to pull air away from a small centrally located radiator. Contributing to this was the front wheel and fender diverting air to only the outer sides of the radiator.

The wind tunnel showed that incoming air came in at such an angle that a substantial part of the flow simply whisked by the front of the radiator then to be vacuumed away by the side slip streams. Even though this was only partially happening -- still the decrease in air volume entering the radiator created a need to enlarge the radiator which the designers would not allow.

Let's say this air divergence problem reduced the incoming air volume by only a third. Then 67% of the incoming air gets into the radiator. But you are restrained from building a bigger radiator and 67% is not enough cooling. HMM!!! This a lot like our XX problem where we are restrained from a larger radiator or upgrades because they don't exist in the market place.

From threads on this forum, it can be seen that fans with more blades, such as Suzuki riders enjoy -- are not available for the XX. More blades, faster fan motors, better coolant... They don't exist for the XX, water wetter notwithstanding -- it has it's own problems.

Harley's solution was suggested by an engineering professor -- to simply add a small set of louvers to each side of the radiator's front casing. The louvers act to stir the incoming air preventing some of it from careening off the face of the radiator. An added element was the back pressure created by trying to push more air into the radiator -- the faster the bike went the more back pressure built up in front of the radiator which caused the careening effect to build up even more.

So the faster the incoming air the less a percentage of it gets through the radiator.

The solution of using side louvers -- acted to stir the air up long enough so that it had a chance to get sucked into the radiator instead of careening off of it.

So, the issue is then -- can these small sets of louvers work on the XX to increase the XX's radiator's cooling capacity???

The original V-Rod louvers where built out of Fedex box cardboard and duct tape.

You would need about 4 or 5 strips of cardboard for each side. The strips should be about 1.5 inches wide. Doubling the cardboard and securing it with black duct tape to the inner fairing should be enough support to test the idea.

As crazy as this may sound, I am going to try this out.

So, one purpose of this thread is to ask others to try it. Perhaps, have various members try different numbers and sizes of the louvers... and then report back. A good idea would also be to go look at a V-Rod radiator on-line so as to get an idea of what the louvers actually look like. If anyone knows how to post photos on this thread and finds some of the V-Rod louvers please do so.

Okay, is anyone game for this experiment in trying to overcome the XX's cooling problem. The summer is coming and so this could help if it works. And if it does, then some enterprizing machine shop might actually make permanent non-cardboard louvers at a modest price for all of us to enjoy.

Whadaya think yah'll?

[Redbird]

I've never had a problem with overheating, or even running hot, as long as I could keep the bike moving.

Your solution would seem to be aimed at improving cooling at speed, which I've never had a problem with, nor read of others here having a problem with. It's the low speed, stop and go traffic situations that get the XX heated up.

Is your bike running hot even when you're not in traffic? What temps are you seeing?

[v00d00child]

Honda engineers put function before form. Obviously, the XX was designed for high speed. Even the clutch and front brake levers were profiled for aerodynamic efficiency. Vortex generators, or turbulators as they're sometimes called, reenergize the airflow, but at the expense of added drag. This drag won't cause problems while you're cruising to the nearest Starbucks, but let's face it, HD is bragging about the Vmax...I mean Vrod... hitting 141 mph--that's what, 3rd gear on an XX?

My 97 has never had overheating problems, even in hellish KS & TX summers in 105F+ heat and 90%+ humidity. My ceramic coated header dropped engine temps noticeably. Also, internal & external fouling factors can drastically reduce thermal efficiency of the radiator--adding a fender extender to prevent muck from clogging the fins, and flushing the radiator and changing the cooling to remove slime from the internal fin surfaces will help.

[xxtraspec99]

Redbird,

One affects the other, riding at speed cools things down, riding in town traffic heats things up. Louvers would cool things faster and keep the engine cooled longer -- that is if we could get them to work on the XX.

Even when the engine temp light shows acceptible temperatures, XX's are generally known for heat getting up to the rider. Wait until summer if you dont' remember this problem.

Further, I put a small unit on my dash which measures both voltage and ambient temperature. I notice that the dash heats up to 100 degrees and above very fast -- and this is in 50 degree weather. The main purpose of the unit was to monitor voltage the ambient temperature was just an added benefit.

Also, look at the inside of the fairing pieces. You will see an awful lot of heat shielding -- so this is evidence that Honda designers knew the engine would be putting out a lot of heat to the rider. The shields are evidence that Honda engineers were trying to stop the heat from getting to the rider and they did a pretty good job except in summer, and MOST IMPORTANTLY for highly modded bikes that run a lot of performance upgrades and so necessarily run hotter than stock specs.

Do you see what I mean?

For an all stock bike, perhaps improving cooling is not an issue. I'll grant you that, but this board seems to have a lot of horsepower nuts on it, don't you think? As I am one I have to admit this.

[Redbird]

I see your point, and if heat's an issue for you I wish you well in your experiment. It's not without it's merits, I just feel it would be most effective at speeds when the stock cooling system is already doing it's job, assuming it works.

I personally have never had a problem with heat being transfered to me, the rider, even on those 105 degree days- but I do most of my riding in rural settings where the bike never really gets a chance to sit around in it's own heat, if you get what I mean. I am familiar with other's complaints on this topic, though, so perhaps your proposed mod may help them.

Good luck with it, I wasn't trying to shoot anything down, just making conversation.

Out of curiosity, your temp readings at the dash- was this taken while moving or in a stopped/slow situation? Do you have a average reading relative to actual temperature (+10? +20?) I've thought of putting a thermometer on the dash just to track the temps I'm riding in, but it never occured to me the radiator down there would throw it off, though it seems obvious enough now :wink:

[Iceman_40]

I don't know how much it would help, Honda designed the bike in the wind tunnel also. I'm sure they took mesures to make sure lots of air was moving into the radiator.

Also keep in mind, the putting those flares on would also cause the bike to catch more air increasing the drag coefficient....

I'm not sure how much, but you'd be basicly losing HP......

[xxtraspec99]

I'll try and keep notes on how much over air temperature the dash heats to. Could be interesting.

As to reducing horsepower, the louvers are on the inside infront of the radiator and only prevent the air from rushing out the sides. The louvers stir the air up enough so that it has a chance to get sucked in. Theoretically, this sucking in of more air should increase horsepower as it would reduce drag. Again, the louvers are not on the outside.

[XXTi]

I like the ceramic coated header option that vOOdOOchild mentioned. I've been interested in this mod since he first posted it, but I haven't done it yet.

I think Northman coated his header too. Did it help your bike run cooler too Chris?

[MiDNiTXX]

I am having heating problems when stopped. Its mostly due to the added heat from the turbo and how close its located to the radiator. My header is ceramic coated and I added some thermal wrap. The wrap noticeably slowed down the overheating process, but its still there.

I believe my next step is to add 1 or 2 full-time fans to the front side (more room to work with) of the radiator. Any other ideas? (I am using water watter)

And not to steal the thread, I believe the body lines lend themselves to directing air into the radiator (excluding the fender).

[Ronnie]

Not sure if anything would help heating at slow speeds or being stopped.

At idle the water pump just isn't moving enough coolant through the engine and raditor .

[demon]

MiDNiTXX, you might try a bigger oil cooler. That turbo is bound to heat the hell out of your oil.

[aptyp]

on oil cooled motors you're supposed to turn up the idle speed because it speeds up the oil pumping process hence cooling you down faster. could the same idea be applied here?

[Northman]

I like the ceramic coated header option that vOOdOOchild mentioned. I've been interested in this mod since he first posted it, but I haven't done it yet.

I think Northman coated his header too. Did it help your bike run cooler too Chris?

I had mine done last winter, but I never really had a heating problem to begin with. I don't do a lot of "city" riding, so stop & go was not a concern.

I've since sold that header to G2 in Florida, so he'd be a better judge of it's effect on heating.

One other thing that you guys seem to miss is the factory cans are brutal for heating up, and holding that heat, radiating it right into the rider. Both sets of slip-ons I've ran were warm to the touch after any kind of riding.

The factory mufflers burned my ankle on the second day I had the bike. :sad: Too restrictive, and too much metal to soak up the heat, IMO.

[XX4me]

Hey MiDNiTXX

I've been thinking about trying to find what I think they called wind deflectors from the '97-'98 birds. They were the piece that fit in the nose and directed the air flow towards the oil cooler and intakes in the carburated birds. Their about $65.00 from ronayers.com. It should mount with no problems and might improve the air flow, at least at speed, over the radiators. I even thought about adding an additional Earls Oil cooler in the nose behind the deflector and routing either coolant, or in my case intercooler water, through it.

Just food for thought

[Hobicus]

At idle the water pump just isn't moving enough coolant through the engine and raditor .

Exactly right. To test, once it's heated up enough that the fans kick on, gun the motor for a second or two, and the temperature will drop.

The stock cans though... Geezus do they get hot. I've got the scars on my legs to prove it. I'd love to do what Tim did, and have them ceramic coated to reduce heat, or replace them with some slip ons, just to reduce that heat. I just have to worry about slip ons hitting the Corbins.

Maybe I'll pull the stockers off this winter and have them coated.

[xxtraspec99]

Yes, ceramic coating... Where can you get that done?

Any URLs or references would be appreciated.

As to dash temps, the guage that I installed routes to the battery for volt metering and has an internal temp sensor. As I sit here now, I can't remember the manufacturer's name, but I will find out. It was not expensive, about $30. In fact, there is an extra temp sensor that comes with it; the extra sensor has a six foot thin wire with a small black capsule sensor on the end and double stick tape. You can put this sensor anywhere. If you are a racer and have a critical component you want to monitor for over heating you could use this to wire it up and monitor that critical piece. Further, I've seen this device while surfing the web for as little as $18, but can't remember the site. Try "volt meter motorcycle" in yahoo.com.

Also, a caveat here: volt meters are useless more or less. I should have gotten an amp meter. I wanted to monitor how much my accessories were draining the battery. A volt meter won't tell me that very well.

Lastly, the bottom line here, ROCKMEUP, is not whether the XX overheats in its stock design. The issue is increasing the cooling performace of the stock radiator. Whether your particular XX overheats is of no moment. Racers, drag or track will all benefit by a simple mod to increase the capacity of the stock radiator to cool better. Why? Guess? With dozens of HP increasing mods engines get hotter and hotter, keeping them cooler allows higher rpms and more efficient engine performance in general. Now, I don't know how much, to what extent these things will work, or even if these V-Rod turbulating louvers will work at all on the XX, but as it only involves cardboard and ducktape; well, it could be a project worth puttering around with, if you have a mind to putter, if you know what I mean. So, I don't think you, MR. Rockme, have gone over this issue countless times. Improving cooling capacity is now and will be an ongoing concern for any mechanical engineer until frictionless engines come into being. 'nough said!

[Hobicus]

Yes, ceramic coating... Where can you get that done?

http://www.jet-hot.com/ is where Tim (Redbird) got his done.

The issue is increasing the cooling performace of the stock radiator. .... (snip)

The issue is whether it even needs to be messed with. IMHO, the bike cools fine in it's stock configuration, and even with most mods available (Power commander, exhaust cans, jetting, larger fuel injectors) with the possible exception of adding a turbo, heat is not significantly increased to warrant messing around with the Honda design. Even at summer time when it's 100+, I never see my temperature, at speed go above 185 or 190. Sure, it heats up a bit when stopped, or running through town, but it cools off QUICK.

If you're adding a turbo, there's LOTS of things you have to consider. Heat is one of them, but if I was working on it, I'd suggest that a more powerfull water pump would be better, and would not necessarily suck enough horsepower from the engine to be obtrusive but would help move more water through the system.

On the subject of louvers:

Part of the issue with the V-rod is that the extended rake provides lots of space between the front tire and the radiator. At speed, the shorter rake of the XX means that the front tire and fender could quite possibly act as a louver, disturbing the airflow enough to render any additional louvers as uneccesary. Just my $.02

[xxtraspec99]

Reply to Mr. Rockme:

Man, what's happening!!! Don't get your panties in such a bunch, huh!!!

Your quibbling about the use of "mister" is just plain non-sense. Where's your head at???

Man, I respect you and I had no intention of insulting you; especially given the tenor and breadth of the usual insults flung around on this board as if every git-back started out with an "f" word or "mf" word.

So now you're going to complain about mister? What's the fun in arguing if you're gonna be so defensive about your name.

And to back up my claim that calling someone "mister" has nothing to do with insults I offer you the following evidence:

Ahem, the emphatic use of the word "mister" in an argumentative context implies nothing more than a serious tone and generally a call to act with a serious mind or intention. In short, calling someone "mister" means you are asking them to "bone up" and "be serious" or "take this seriously."

Moreover, every television and/or movie mother sooner or later will yell at her child to "get in there and clean up your room, mister." Is that the mother insulting her child??? Or how about this one, "...you better just watch your ps & qs, mister, just wait until your father comes home..." Is it fair to say that the mother is falsely honoring the child and in reality insulting her child??? No, of course not, the mother just wants the child to take things seriously, be a good boy. So, whadaya think?

[xxtraspec99]

Hmm...

Rockmeup: your message has a feeling that you are not putting your best effort into the reply, as if you are just half heartedly responding -- you don't pay much attention to detail.

For example:

1. You say I should sell the louvers to Ford, but the title of the thread and the first entry show that the louvers were invented by Harley for the V-Rod. So how could I sell the louvers to Ford? Your sarcasm just doesn't follow. It sounds like you wrote that reply half asleep.

2. You also describe special constructions of radiators as if that were really an option for an average rider without race team money. On the other hand, we can budget it or my name isn't Steve Jobs.

3. You say you don't argue on the Internet but your replies show the rhetorical skills of a college linguist major.

4. You believe the XX doesn't have a heating problem but you want to sweep under the rug -- the fact that inside the fairing pieces there is heavy insulation. As far as I'm concerned that's a smoking gun that shows the Honda engineers knew about the overheating from the beginning. Those engineers didn't put that insulation in for nothing. It's expensive.

5. Further, the overheating comes from the speed king design spec. itself which the engineers were targeting.

[To achieve the fastest bike speed in 1997, Honda had to reduce drag coefficient drastically. As you must know, horse power and speed do not increase at the same rate. For example, if a Harley goes 100 mph with 50 hp, it will not go 200 mph with 100 hp. With 100 hp a Harley will go about 135 mph (a V-Rod with 115 hp has a top speed of around 135-140). To overcome this drawback, Honda reduced drag so that it would not take even 50 hp to go 100. With the XX's fairing, an engine with 35 hp could get the vehicle going about 100 mph or so the theory goes; and therefore, getting up to speed king speeds need take far less horse power, or only 125 hp or so..]

6. The XX has a coefficient of drag of 0.0085, which as you know, is extremely low. This low drag is achieved by creating a slip stream where the nose fairing and fender split the air like a knife through butter. But this is at the expense of lessening the amount of air that hits the radiator. Thus the radiator was enlarged and the insulation put inside the fairing to make up for this. That fact means the engine DOES routinely overheat but the rider is protected from it most of the time, the insulation.

And no amount of your rhetoric can pretend otherwise.

7. Lastly, you also state without sufficient foundation that the instrument on my dash which measures air temperature -- that you are familiar with it and that it is faulty. But you don't say why, nor do you name the product.

Again, you are trying too hard . We all have bad hair days.

[Redbird]

God damn, we really need that popcorn emoticon. :razz:

[jrdxx]

Is there a seat still available?