DrDyno Posted February 19, 2008 Share Posted February 19, 2008 Hi All, I have noticed that most of the new sport bikes have huge vents cut into their lower cowling (behind the front fender) to allow air to pass over the headers under the crank case. It seems to me that allowing air to pass over and around the header pipes (as close as they are to the crank case) would assist in keeping the Blackbird's engine temperatures cooler. Have any of you tried this and... with what results? Quote Link to comment Share on other sites More sharing options...
Wockman Posted February 19, 2008 Share Posted February 19, 2008 I remember someone talking about punching holes or cutting vents in their lower cowl to let air flow through. I never did read how well is worked or didn't work. I think it was on the .com XX site. In theory it should work, more air flow should carry heat out. I've always thought that I-4 motorcycle engines were designed backwards. Shouldn't the air intake come in the front and the exhaust go out the back instead of the other way around? But these bikes were designed by people smarter than I so I'll just shut my pie hole... Quote Link to comment Share on other sites More sharing options...
jon haney Posted February 19, 2008 Share Posted February 19, 2008 I've always thought that I-4 motorcycle engines were designed backwards. Shouldn't the air intake come in the front and the exhaust go out the back instead of the other way around? But these bikes were designed by people smarter than I so I'll just shut my pie hole... Any motorcycle magazine that covers sport-bikes usually addresses this issue at least once a year, either in a writer's column or in response to a letter. This thread already covers one of the main reasons (exhaust heat). Space for a big air-box and shorter wheelbase are a couple of other reasons. Quote Link to comment Share on other sites More sharing options...
Furbird Posted February 19, 2008 Share Posted February 19, 2008 If you want to get a general idea, try riding around with your center cowl off. Result? The water temp is higher because now that cowl is not forcing air up to the radiator. I put mine back on after one day. Quote Link to comment Share on other sites More sharing options...
runner Posted February 19, 2008 Share Posted February 19, 2008 Many factors to consider. Water temp being the primary one. Space limitations and the lean angle of the cylinders impacts FI and exhaust placement... Quote Link to comment Share on other sites More sharing options...
Redbird Posted February 19, 2008 Share Posted February 19, 2008 Shouldn't the air intake come in the front and the exhaust go out the back instead of the other way around? Cannondale tried that a few years back. I guess it didn't catch on. Quote Link to comment Share on other sites More sharing options...
BarryG Posted February 19, 2008 Share Posted February 19, 2008 Hi All, I have noticed that most of the new sport bikes have huge vents cut into their lower cowling (behind the front fender) to allow air to pass over the headers under the crank case. It seems to me that allowing air to pass over and around the header pipes (as close as they are to the crank case) would assist in keeping the Blackbird's engine temperatures cooler. Have any of you tried this and... with what results? Get a carb'd one.... Quote Link to comment Share on other sites More sharing options...
TX1100F Posted February 19, 2008 Share Posted February 19, 2008 I'm planning on getting mine ceramic coated soon. I'll take some video before and after with my IR temp gun. BTW I discovered that the hottest part of the exhaust is NOT the head pipes as they exit but rather the junction where they come together down below. Kinda surprised me at first but then made sense as I pondered the cumulative heat energy as it becomes more concentrated. :icon_think: Quote Link to comment Share on other sites More sharing options...
TeXTrain99 Posted February 24, 2008 Share Posted February 24, 2008 Anybody wrap thier headers? If the head pipe junction is the hottest section how about just wrapping that section? Quote Link to comment Share on other sites More sharing options...
cbrxxquad Posted February 24, 2008 Share Posted February 24, 2008 Anybody wrap thier headers? If the head pipe junction is the hottest section how about just wrapping that section? If you do a search you will find corrosion is a problem with raps. If you want to lower the heat, rather keep it in the headers instead of it radiating out, do the ceramic coating. I did mine for 125 dollars. Could not tell anything different in the radiator temp. I put a v piece on my quad and the temp went down. Now it is not relevant to the bike, but it is info. Now I have the bike and am waiting for the v piece and the temp is higher than the quad, and I will have the new v piece tomorrow and I bet the temp will go down. Without it the air will go around the radiator and cool the headers more, but the temp in the radiator is higher. Well engine. I did some testing on a race engine cooling system. We found that retention time in the radiator was more important to lower the engine temp. That required a higher thermostat setting. Allowed the radiator to lower the water temp for the water incoming to the engine. The water in the engine needs to be 212 degrees to cook the moisture out of the oil and the cylinder wall temp being higher the fuel did not condense on the metal. Made more hp on the dyno. And a lot more torque. A lot flatter torque curve. Quote Link to comment Share on other sites More sharing options...
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