| Author | Message | ||
     Sonny |
Brucelee, You seem to be a big proponent of the right side air scoop. How many miles did you have on your scoot before you installed it? How much has it reduced the fan usage (i.e., by 1/3, 1/2)? Your comments appreciated. | ||
| Brucelee |
Yes I am. I now have 11K on my XB9S. Installed at around 5K. Change has been dramatic. The fan never comes on when I am riding (came on once when I was dead stuck in traffic in the desert w/temps at 100Degrees). Has come on maybe 5 times total AFTER shut down. These times where in very hot temps and during very hard riding. The fan time after shut down is quite short. All in all, the best mod I have done and it looks great to me also. I will post some pix later today as I have done some other mods too. I should mention that I think Red Line 20W-50 also makes a difference in fan time. That is one great oil. Any questions, ask away. | ||
| Blake |
This is a very interesting issue for me. So I have some serious questions for you.  1a. Do you view the normal operation of the cooling fan as problematic? 1b. If so, why? 2. Can you imagine anything problematic for an engine that fails to reach a high enough operating temperature? | ||
| Rocketsprink |
At Homecoming this topic was brought up at one of the seminars. Buell engineers said that the factory scoop, if you want to call it that, when tested at their Arizona Proving Grounds proved to be sufficient to cool the rear cylinder. I believe them. Looks wise, I like the aftermarket scoop look much better. No doubt it helps keep the fan from coming on so much. But I believe that the fan was designed for just that reason!! | ||
| Brucelee |
"1a. Do you view the normal operation of the cooling fan as problematic?" Hard to say, I guess you would have to define "problematic." I certainly find it annoying and like not having to listen to it whirl away. Having said that, it is certainly preferable to baking the read cylinder head. 1b. If so, why? "2. Can you imagine anything problematic for an engine that fails to reach a high enough operating temperature?" I can imagine that. However, I don't imagine that this is actually happening. If this were so, wouldn't this also be happening for the FRONT cylinder? After all, it is sitting right up front, getting all the air it can handle, certainly more air than the rear cylinder is getting with two scoops and all. From where I sit, the Buell guys were rightly concerned about the REAR cylinder due to it being tucked up in the frame and behind the front cylinder, thereby impeding normal cooling air access. This is obviously not an issue for the front cylinder or a fan would be up there too. Hence, Buell installs the left side scoop, the small right side scoop AND the fan.. The fan is obviously the back up deal and only comes on at some pretty high temps, and a pretty good idea at that! As Erik has pointed out, they are concerned about the oil in the head literally vaporizing at these extreme temps, hence the fan. I see the added cooling air that is brought on by the larger right side scoop as a simple way to further avoid these extreme temps. Of course, the fan is still back there just in case, which was the case the other day after I climbed Palomar Mountain. Make sense? | ||
| Brucelee |
"Buell engineers said that the factory scoop, if you want to call it that, when tested at their Arizona Proving Grounds proved to be sufficient to cool the rear cylinder. I believe them" This actually CAN'T be true or Erik would not have had to patent the application of the cooling fan. In fact, the factory scoop cannot do the job all by itself, hence the fan. Further, at times even my supplemental right side scoop is inadequate, and hence why my fan can STILL run under some conditions. I am glad I have the fan back there, I am just much happier that it is required so infrequently now. I also have to say that I find the failure to accept that Buell may not have gotten something on the XB perfect to be puzzling. We have all ragged on about the mirrors, the belts, the clutch cable, even the trans. Several improvements have been made by Buell, such as a new trans. Why is it so hard to accept that they may have simply not gotten this issue right? Don't get me wrong, the fan works. I simply think the fan and two scoops works better. | ||
| Glitch |
Can you imagine anything problematic for an engine that fails to reach a high enough operating temperature? Trust me, that rear cylinder is getting plenty hot! | ||
| Aeholton |
Blake - Serious question for you: Do you think the rear head with aftermarket right side air scoop is running too cool? | ||
| Blake |
Bruce, How is it that you imagine the rear cylinder head is being "baked"? Does it not have a computer control multi-spead fan that kicks in as needed. Annoying fan noise I can see. Aeholton, I don't know and as a professional in the field wouldn't pretend to know. It is in reality an extremely complex system. Such issues are why we have engineers in the first place. I the rear cylinder head easily could be running too cool in certain situations. I think it is possible that an added scoop may also affect the front cylinder as well. The front cylinder offers up a red hot exhaust header directly in front. It is not surprising that it would not be problematic to have the cooling airstream, if indeed it is doing so, impinging the front of the front cylinder. Air-flow, especially around a moving front wheel, may not be as intuitive or simply as one might imagine. To make any kind of assumptions about the cooling airflow would in my opinion be very risky. What would happen if you cool the rear cylinder more on one side than on the other? What if the added scoop cools the front of the rear cylinder head, but lessens cooling on the rear, nearest the exhaust port? | ||
| Glitch |
Blake, You need some major seat time on an XB. Go over and check out Keith's bike while he's changing spark plugs, so you can see just how crammed in the frame the rear head is. You are sitting on top of the rear head. With a pyrometer, you can see that even in the dead of winter (okay Atlanta winter) the rear head is way hot enough to kick the fan on, and it does. The head being in such a closed in space, leads me to believe that there is almost no way to get uneven heating of the head. I was told by a VERY reliable source that one of the main reasons for NOT having a right side scoop, was because of the "bread box syndrome". For those that don't know. The tuber's were blessed with an air box the size of a bread box. It was often the first thing to disappear, not unlike the XB's Mickey Mouse ears. You simply can not look at an M2 and think XB. | ||
| Brucelee |
"How is it that you imagine the rear cylinder head is being "baked"? Does it not have a computer control multi-spead fan that kicks in as needed" Those were the actual words that Erik used to describe what would happen IF the rear fan had not been added to provide cooling. Given that and given where I do my riding, I don't see ANY way that my back cylinder is running "too cool". Moreover, my bike is running great, so if it is suffering form the scoop, it is hiding it well! I also don't buy you logic on how the front cylinder is "heated" by its header but perhaps, the back one isn't? Sorry, Blake, I think you are reaching here. Having said that, it is free country. Don't add a scoop, it is fine by me. | ||
| Brucelee |
Remember guys, the XB comes with a right side scoop, it is just really little! | ||
| Brucelee |
"What would happen if you cool the rear cylinder more on one side than on the other" It seems to me that this is more likely to happen with only one large scoop on the left than with two scoops of equal size. | ||
| Blake |
"Those were the actual words that Erik used to describe what would happen IF the rear fan had not been added to provide cooling." Clarification: That was the word used by Erik in describing what happens in the cylinders heads of EVERY engine lacking an active and effective cooling system that is able to function post shut-down. How does a scoop aid in addressing post shut-down heat soak issues? Unlike some folks, I'm not reaching for anything and don't pretend to know something about an issue I have neither studied or nor analyzed. Yet, I am an experience mechanical engineering professional. I understand all too well that it is most often not what we think we know but what we fail to imagine in such scenarios that is often the cause of serious problems. The folks who pledged that the space shuttle was okay to launch in near freezing temperatures were confident that they knew better than the engineering experts who designed the solid rocket boosters. There is one undeniable very simple fact that I can state on the issue. It is that no one here outside of the expert Buell and H-D engineers who actually worked on the XB engine and its cooling system is qualified to make any kind of technical statement about the possible overall long-term effects of alterating/modifying the XB cooling system. Failing to imagine how a front mounted red hot header pipe and exhaust port might affect the heat transfer environment of the front cylinder while on the other hand imagining that a right side air-scoop provides nothing but an improved environment would seem to be difficult to reconcile. When I said "side" I was speaking generally, and more wrt the front versus back sides of the rear cylinder. | ||
| Blake |
Who said the rear cylinder is not heated by its header/exhaust port? Please don't put words into my mouth. I generally try to state exactly what I mean.  | ||
| Brucelee |
I am not going down this road with you Blake. I know where this is headed. Scoop or no, I do not care. I have one, I like it and I don't need the debate. Others can do what they want. The thread started due to someone wanting my opinion and experience. If I wanted to get into a technical debate, well, I would have become an engineer. Life is WAY to short. You are right, I am wrong! Tah! | ||
| Slider |
I'm confused...Is there a pic of this larger scoop somewhere?...is it a custom mod?... I'm currently running my right side scoop off. | ||
| Brucelee |
American Sport Bike has one. | ||
| Blake |
What am I right about Richard?  I don't know one way or the other or anywhere in between whether or not augmenting an XB's cooling system via an additional air scoop is a great and wonderful thing or benign or problematic. It could be all three depending on the specific situation and ambient conditions involved. I am sorry that my questions and responses to some of your comments have so offended you. That was not my intent. Discussion is good. Folks can learn through discussion. I know I do. Turning a productive discussion, especially a technical discussion into a personal issue is sucky. Please try to avoid being sucky. Trojan aka Adrenaline Moto also sells a right side air scoop. | ||
| Rasmonis |
What ever happened to thread where a few guys where in the process of making a two piece right side scoop that almost exactly matched the stock one (in size and appearance)- no painting required? I remember they posted pics and it looked great. | ||
| Glitch |
How in the world could you get un-even heating/cooling on the rear head? Please, Blake, take a real good look at an XB, without the air box, without the seat. Try to change the rear spark plug. Now go for a long enough ride where the bike actually gets hot. Then tell me, how in the world you could get un-even heating/cooling with the addition of an air scoop. Take your pyrometer with you as well. I'm tellin' ya, you'd have to do something pretty drastic to cool/heat the rear head un-evenly. I was in the right-side-air-scoop-is-poop-camp, ask Brucelee, he'll tell you. Between using common sense, and reading, I've changed my mind. I'd even buy one if they weren't so expensive. | ||
| Brucelee |
"I'd even buy one if they weren't so expensive." I have to say, I think it could be cheaper. Hard to figure why it is the price it is. | ||
| Glitch |
My take on the price is that the mold is very expensive. To keep the explanation as simple as possible, as far as molds go the air scoop is pretty complex. Carbon Fiber in itself is cheap, but (if I'm not mistaken) they cure the air scoop in an autoclave, adding to the expense. Now add to that the fact that the market is very small (manufacturing wise) it's expensive to make. | ||
| Sonny |
Thanks Brucelee, and others who have commented. The XB is the only bike I've ever had (air cooled or liquid cooled) whose fan is *constantly* on. All other fans only come on when stuck in traffic. And all other air-cooled bikes such as BMW boxers, Ducati desmodues, seem to do just fine w/o a fan at all, never mind one that is on all the time. To me, the fan whir is annoying. These bikes should rumble, not whine (by the way, my bike pings quite a bit too, no matter what brand of premium I use). I really love my Buell, but I'm getting frustrated by this. | ||
| Aeholton |
What ever happened to thread where a few guys where in the process of making a two piece right side scoop that almost exactly matched the stock one (in size and appearance)- no painting required? It either died out or was removed, as the folks making it are not site sponsors. However, I tracked it down and have one ordered. It was shipped last week from Europe and I'm anxiously awaiting it's arrival. It wasn't cheap, but requires no painting. I thought about going the carbon fiber route, but that would mean buying the left side to match (even more expensive). | ||
| Brucelee |
Two quick observations! I wonder what the cost of the left side scoop is from Buell. My bet is that it is not that expensive, as I have found Buell parts to be very reasonably priced indeed! Also, once the fan noise is subdued, in fact the bike DOES sound great, esp with the Race Kit muffler that I have. However, I now really notice the whine of the fuel pump. Anyone know a way to get a quieter fuel pump? The sound of the motor would be AWESOME without it having to compete with that damn whine! | ||
| Darthane |
Sonny, if you haven't already, switch to synthetics. Your fan will come on less often. I've often thought about adding a right-side scoop, but my fan doesn't come on often enough to bother me (it's yet another conversation starter on a bike chock-full of them, actually) and they're just too damned expensive. If I were going to spend that much, I'd sooner replace the left-side scoop with a CF one just to get rid of the dull-black stock plastic one. Those fuel pumps...I just don't get it. Sometimes I can't hear it at all except when it primes, other times I can hear it over my engine noise. There doesn't seem to be any correlation between how much gas is in the tank, operating temp, etc, either. I suppose it's just how bitchy it feels that day. LOL | ||
| Glitch |
I suppose it's just how bitchy it feels that day. Just keep a record as to when this happens. Get a calender out and see if it happens every 28 days or so... | ||
| Darthane |
Already thought of that. Doesn't pan out, either. ...maybe it's how close I parked it to that fugly Japanese bike in the back of my garage that night? | ||
| Glitch |
Jealousy rears it's ugly head...um...fuel pump. |
