| Author |
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Ft_bstrd
| | Posted on Thursday, September 06, 2007 - 09:26 pm: | 
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I can second the fuel economy. ChadHargis and I were running in the mountains pretty hard. We were in third and fourth most of the day with the RPMs between 4,500 and redline. We each had the same mileage. We each made it to 170 miles and the light still hadn't come on. We each got exactly 50MPG. We each have the race kit and open air box. We each weight 235lbs.
It was a pretty good test.
I have been considering doing the conversion, but for longer distances the higher RPMs would be a little more fatiguing. I run right at 80MPH at about 4,000 RPM. That would put the RPMs at almost 4,500. I think that would get a little annoying for really long distances. |
Jlnance
| | Posted on Thursday, September 06, 2007 - 09:46 pm: |
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I thought I was gonna have a heart attack.
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Jlnance
| | Posted on Friday, September 07, 2007 - 09:21 am: |
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Silly question maybe, but why do you think they over-geared the bike in the first place?
I have a theory, some of it is based on facts, and some of it based on guessing.
I think it has to do with EPA regs. One of the things the EPA regulates is noise. Not just exhaust noise, but all the noise from the bike, and they are fairly stringent regs. Some of the older Buells had the exhaust exit on one side of the bike and the airbox on the opposite side. I'm told the reason for this (as opposed to having the exhaust vent out both sides of the muffler) is that the bike couldn't meet the noise requirements if the exhaust came out both sides. So on one side of the bike you have exhaust noise and on the other you have intake noise.
Besides the exhaust and intake, another noise source is gear whine from the transmission. Since 5th gear is direct drive, there is no gear whine when you're in 5th.
The above is fact. What follows is my speculation.
They need shift points that get the bike into 5th gear by 55 mph, and they need the gearing tall enough that the engine rpm never cause the bike to get loud. They probably need the rpm low enough to keep the interactive muffler valve closed.
If they geared 1st lower, you would have to rev the bike too high before switching to second.
If they lowered all the gears, 55 mph would be too loud.
I suspect the reason the manual has the shift points it does, is that Buell needs to claim those are reasonable shift points when it does the noise test.
I think that w/o the EPA, the gears would be spread out more. First would be lower and Fifth would be higher, and shifting would be something like this:
1->2 20 mph
2->3 40 mph
3->4 60 mph
4->5 80 mph
Actually those aren't bad shift points for our current gearing. ;) |
Buellistic
| | Posted on Saturday, September 08, 2007 - 10:29 pm: |
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Since you'll are puting the XB9 motor sprocket on your XB12's(which is the same as the TUBE FRAME motor gearing) what are you selling the XB12 motor sprocket and chain for ???
In BLASTing
LaFayette
Ljenne73c@verizon.net |
Bertotti
| | Posted on Saturday, September 08, 2007 - 11:51 pm: |
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I'm holding onto mine in in case it turns out I don't like the change, or to put it back to stock for resale. I keep wondering if Buell will put out a more dirt oriented bike. |
Bertotti
| | Posted on Monday, September 10, 2007 - 05:00 pm: |
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The primary and rss are out till mid next week. I didn't think the 9 primary was that popular. Who else has ordered one and is installing it? |
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