| Author | Message | ||
     Jlnance |
I'm considering going to the XB9 primary in my Uly. My only concern is that it will reduce my gas mileage on the highway as it essentially changes 5th gear into 4th. Today I did an experiment. I filled up the bike, rode the 86 miles from Raleigh to Greensboro in 5th gear, filled it back up and rode home in 4th gear. I made it a point to keep the bike between 5 and 10 over the speed limit, which usually put me between 70 and 75 mph. Traffic was flowing so I didn't have to alter my speed much. The result? 5th gear - 50.4 mph 4th gear - 53.1 mph I'm rather stunned. I'll need to repeat this a few times to get some confidence in the numbers, but it doesn't look like I'll be loosing anything by going to the XB9 primary. If anyone else would like to try this experiment, I'd love the data. Particularly if you cruise a little faster than me. | ||
| Maximum |
Jlnance: Why do you want to do this? I feel like I would rather go the other direction, like having a sixth gear. | ||
| Jlnance |
Maximum - Several people have changed to the XB9 gearing and report that it greatly improves low speed operation. I hate running the Uly below 25 mph, it just jerks and and bucks if you don't slip the clutch. My preference would be to just lower the gearing of 1st, but thats not something I'm capable of doing. Given the mileage numbers I posted, are you sure you want a 6th gear? | ||
| Maximum |
OK, that makes sense. I guess that I didn't have that same concern because I have the race kit. The race muffler gives smooth performance all the way down to 2,000 rpm. That was an interesting test though, I may have to try that out on a tank full of my normal commuting. I normally get 49 mpg during my typical work week riding. | ||
| Gotj |
Jlance, I was of the same mind as you until I installed the 07 air box. Now, on level ground, I can let the clutch out at idle and it is moves away smoothly. I checked your profile and you give Erik his due but he knew enough to change the airbox for 07 so shouldn't you? :-) I haven't done the ECM reflash but I have read several posts that say it improves gas mileage after changing the airbox. At about $35 and one-half hour of time, I would recommend changing the airbox even if you decide to change the gearing. My only thought about your experiment is to check for any significant wind and its direction on that day. Another thought for followup tests would be to do the test on a loop back to back and with possibly a somewhat shorter distance so that weather could be less of a factor. Just my 2 cents. | ||
| Spike |
Interesting results. I haven't done any similar experiments as far as gearing goes, but I have noticed that the higher my speed and RPM during interstate travel, the worse my mileage will be. For example, on my last trip to Daytona we ran 75-85mph for the first two legs of the trip and I was showing about 45mpg the first two times we filled up. On the third leg we toned it down a bit and only ran 70-75mph most of the way and I got 52mpg. Also, I usually get my best mileage on backroads where the speed is kept below 65mph or so. I had always figured it had more to do with the extra RPM rather than the change in speed, but your results indicate otherwise. Keep us posted if you run more tests. | ||
| Cavi |
I have the XB9 gearing and the 07 air box, and the race muffler and ECM. I did the TPS myself. The bike is great, and I love the xb9 gearing. Would a 6th gear be good? Not really, I would not really need it, even though it might be nice to know it was there. I ride daily to and from work, about 50 miles total, and I average 70 to 80MPH. Mostly 70, and it is right around 4000, slightly below, and 4250 at 50, so really a 6th gear is not necessary unless I wanted to either go over 120 or ride at 80MPH way under 3000RPM. Personally I try and keep the bike between 3500 and 4500, it sounds great there and the Roll on power seems to be better over 4000 than at 3000. Now a dumb question, With the race ECM I do not need the 07 Reflash do I? | ||
| Ft_bstrd |
No on the reflash, Cavi. You are good to go. | ||
| Jmhinkle |
"Jlnance, I was of the same mind as you until I installed the 07 air box. Now, on level ground, I can let the clutch out at idle and it is moves away smoothly" +1. '07 box cured the surging and low rpm tractability. The Drummer added 500 RPM of useable area from 1.5 to 2k. I need a sixth gear not a low range. Interesting mileage finding though. If I put a lot of miles on the bike, I would definitely be willing to help out. Unfortunately, my commute is short and I don't get to highway speeds very often. | ||
| Madduck |
I would only change to the 9 gearing if you want to run non paved roads and some dirt. Altho it really does make the bike a lot more fun in town. The real improvement comes with how it handles the loose stuff. Also seems to lessen the need for rear brake as it really increases the engine braking effect. | ||
| Maximum |
What's involved in switchin' out the gearing? Expense and time? Just curious. | ||
| Jlnance |
Maximum - The gearing switch requires the XB9 primary sprocket, & primary chain. You have to remove the transmission cover to replace those parts, so you will need a gasket for that as well. American Sport Bike sells a kit for $195. I haven't priced the parts from Appleton. Gotj - What happens to the mileage after you put the 07 airbox on? I was under the impression it went down unless you reflashed the ECM. My problem is I don't know how to get the ECM reflashed. Can you just ask a dealer to do that for you? Where are you all finding the race ECMs? I thought they were discontinued? Will they work the the standard muffler (ie, they have the exhaust valve driver?) | ||
| Jmhinkle |
Race ECM's are not discontinued. The entire Race kits are because they discontinued the muffler. You can still order a brand new Race ECM at any dealer. I just sold the one I had to another Uly rider on here. The Race ECM does not actuate the exhaust valve so you will have to wire it open or go with an aftermarket exhaust. As far as the reflash, any dealer can do it, but only a smart and friendly one will. Your mileage will drop after the lid change though. To do the reflash, all they have to do is hook up the digital technician and put in your VIN but change the '06 designator to an '07 one and the reflash will appear for them. Takes a total of 10 minutes max. You can also send it to Appleton and they will flash it and send it back, but that involves some down time and shipping costs obviously. | ||
| Thesmaz |
I too would like to have a 6th gear for autoroute/autobahn/hiway/motorway riding here in Europe. At 80mph/130kph I typically get around 40-45mpg with bags nd I really think that the bike could do better. When riding slb I keep the rpms around 3700-4000 and end up having to stop around 140-150 miles to fill up. I'd like to run faster when I'm in Germany but I don't want to have to fill up every 90-100 miles. The bike and myself are capable of running at 100mph with no problems or discomfort but I don't do it because of the fuel consumption. Is there a six speed tranny available for the sportster based motors? Jlnance, the ECM's are available not the Buell Race exhaust. (Message edited by Thesmaz on May 21, 2007) | ||
| Gotj |
Jlance, "What happens to the mileage after you put the 07 airbox on? I was under the impression it went down unless you reflashed the ECM. My problem is I don't know how to get the ECM reflashed. Can you just ask a dealer to do that for you?" I ordered the box when I got the bike so I didn't have a baseline mpg to compare to. I get about 40-45 mpg in mixed driving but I'm a big b*strd, not Fat, so YMMV. :-) Regarding the reflash, Jmhinkle hit it on the head. My dealer will do it for 1/2 hour time charge. Back when I asked, they didn't even know about the process. When they asked, they didn't learn about the 06/07 designator swap and would have to go to the floor, find an 07, and copy the whole serial number to enter into the system. I may get it done over the winter when things are slow in the shop. Maybe even do the XB9 swap. | ||
| L_je |
I swapped out my airbox for the '07, and have yet to do the reflash. Here are my observations... First day or two after the swap: noticeable power gains...front wheel lifted under normal riding conditions...gas mileage down ~5% After the first week: gas mileage back up to pre-mod levels of 45-48mpg...wheel no longer lifting during "normal" riding. I think two things at play here: 1) ECM learned to deal with the higher airflows, much the same way (but opposite) it would compensate for an aircleaner that fouls up over 5-10k miles. 2) The operator compensated for any power gains. A wheel off the ground will impress some police officers and win you a funny look and a friendly wave, but from others, it will only draw a scowl and the tisk-tisk finger waving back and forth. Now that I'm 2 or 3k miles beyond my airbox swap, I have a lot of sound and fury, but it signifies nothing. I'm back on the '06 EFI curves that Buell saw fit to supersede with the '07 curves...so I'm going to go in for the '07 remap. The intake noise makes the bike sound more aggressive, but I think the EFI has corrected for the less restrictive airflow. Thesmaz, I can run 80-90 mph all day and still get in 160+ miles before the fuel light. Depending on where you fall on the excess-power curve, 6th gear may not buy you much in the way of fuel economy at higher speeds. | ||
| Teeps |
Just to stir the pot and add to the controversy: With the stock muffler: I noticed no change in mileage with '07 airbox and stock muffler. Either before or after having the '07 ECM calibration, nor did I notice any appreciable difference in low speed drive-ability. Or, for that matter fan operation characteristics. To further add to the confusion, even with a TFI unit connected, I've noticed no differences. Oh yea, mine pings too, stock muffler, both before and after '07 airbox, ecm flash, TFI and even tried '05 stock ecm. (Message edited by teeps on May 21, 2007) | ||
| Jlnance |
at 80mph/130kph I typically get around 40-45mpg with bags nd I really think that the bike could do better. Run it in 4th gear and see if your mileage goes up like mine did. | ||
| Windrider |
Jlnance, I too have been thinking about going to the XB9 Ratio on the primary of my Uly. I would like this for low speed tooling around on dirt roads, which I do a fair amount of. 1st gear is a a bit high for tight dirt riding and I end up do more clutch slipping than I care for. I avoid the freeways if at all possible so I think I would be OK with spinning the motor a bit faster for those occasional freeway runs. And now for more Airbox/ECM controversy! I put on an 07 airbox right before taking a 400 mile road trip. I average 58 MPG running pretty steady at 65 -80 MPH on a combination of country two lane and freeway riding. This was right where my fuel economy was with the 06 airbox. Low RPM operation seems to be a bit better with the new airbox, but still not as good as I would like. When climbing up steep mountain roads in first gear the bike is still rough below 2.5 K RPM. I plan on getting the 07 flash but my local dealer was clueless when I inquired about it earlier and instantly started mumbling about how overbooked their shop was and how they should empty my wallet. I will try them again this fall when the frost hits and if they are still hard to deal with I will send the ECM to Appelton where they know the process. In my experience, the 07 airbox alone did not hurt fuel economy a bit. It also did not cure my Uly's low RPM stumbling. I think that L_je might be right: the ECM just adjusted for the increased air flow. And if Buell reads this: How about a 6 speed where 6th lines up with the current 5th and 1st is like the current gearing with XB9 primary? | ||
| Gotj |
Jlance, FYI, your trip to Greensboro gained about 600 feet in altitude and the return trip dropped the same amount. An option to a loop route I suggested above for later experiments is "out and back", once in fifth and the second in fourth. | ||
| Cavi |
I have the XB9 gearing, and I will state that many here are way too worried bout installing it. It really does make low speed a non issue, but it really does not make a top end difference that will change your life, or make it that you have problems on the freeway. Keep in mind this bike is sportbike at heart not a Harley cruiser, it really is not meant to be ridden under 300RPMS, it is a much happier bike over 4000. Of course this is just my take. If i wanted calm and boring I would have bought a BMW. | ||
| Windrider |
Cavi, Do you keep track of fuel economy numbers? Did you notice any change in fuel economy when you converted your primary to the XB9 setup? | ||
| Sanchez |
> I have noticed that the higher my speed and RPM during interstate travel, the worse my mileage That has more to do with speed than RPM. Wind resistance increases with the square of your speed. E.g. when you double your speed, you quadruple the wind resistance. |
