| Author | Message | ||
     Hootowl |
There have been a few upgrades to the fuel maps for the stock ECMs. Is there an updated map for the race ECM as well? | ||
| Ara |
BLAKE: I rejetted my '09 S3 this weekend, as you suggested. I already had the stock #195 main jet, and since that would be quite a change from the #205 in had in it, I opted to start with that. I have a Dynojet Stage 1 kit in it, and discovered that the H-D jet is incompatible with the Dynojet emulsion tube - different thread pitch. So I replaced both the emulsion tube and the main jet with the stock Buell parts. Took it for a ride and I think I have better throttle response now. Top speed attained was 110 mph, but the bike was still pulling when I ran out of safe road. I have a question for you. The two emulsion tubes are considerably different. The stock part has 18 small holes in it, 12 of which are down by the threads. The Dynojet emulsion tube has but one hole, also on the bottom near the threads. What do the holes do? What's the thinking behind the Dynojet design? Thanks in advance, Russ | ||
| Blake |
The holes allow air to begin mixing and atomizing the fuel. I don't know the thinking behind the dynojet emulsion tube design. That might be why you needed the 205 jet. Aaron would be the guy to ask. | ||
| Ara |
Thanks very much, Blake. Aaron, can you please educate me further? Russ | ||
| Jim_Witt |
Dynojets design I also found this (read the last paragraph), Carb float level and gas mileage Float level has a very important effect on A/F ratio. The carb is designed to operate with the fuel at some known level in the fuel bowl. To simplify explanation, consider only the main fuel circuit. The main fuel circuit consists of a tube that goes from the middle of the venturi to the bottom of the fuel bowl. Inside this tube, typically at the bottom, is a fuel restriction oriface, called a "jet". Also in the tube is another tube that allows air to mix with the fuel pulled up, called an "emulsion tube". With most designs, the jet screws into the emulsion tube. So, you have this tube sitting in gas. As air gets pulled across the top of the tube, gas gets pulled up the tube and out into the moving air. Just exactly like the way a paint gun works. Or a perfume bottle. The purpose of the jet in the bottom of the tube is to limit the amount of fuel, so this has a direct effect of Air/Fuel ratio. Lets assume that fuel sits halfway up the length of the tube. It will require X amount of air flow to put enough vacuum on the tube to pull fuel uphill and into the moving air. If you then raise the fuel level to 3/4 of the way up (cut the distance in half), it now takes X/2 amount of air flow to cause fuel to flow uphill and out into the airstream. So, float level also has a direct effect on A/F ratio. A side effect of this, is the emulsion tube. If you've had a carb apart, you've seen one. It's a brass tube, with a bunch of little holes in it, and the main jet screws into the bottom of it. Those little holes are supposed to sit in air. They are fed an air supply by a hole in the front of the carb called an "air bleed oriface". The idea of this tube is to mix air with the gas, and form an emulsion, sort of like a very bubbly foam. This gives the fuel a lot more surface area. Fuel goes into the vapor state only at a liquid/gas boundary. Fuel, by the way, will only burn when it is in the vapor state. So, the more you vaporize the fuel, the more of it gets burned. Like I said, those holes in the emulsion tube are supposed to sit in air, with the fuel level being just below the lowest one. If the fuel level in the bowl gets too high, you cover up the emulsion holes, and pull fuel, not air, in thru them. This, in a sense, makes your main jet area "bigger". So, you change the A/F ratio to richer. You also end up with less emulsion, which can effect the vaporization efficiency, and thus effect power. You then would need more throttle to get the same amount of power, so gas mileage goes down. If you have ever installed a Dynojet kit in a CV carb, you've seen that their emulsion tube has only about 1/4 the amount of air bleed holes as does the stock tube. That kit is designed to throw more raw fuel out the main fuel oriface than stock. This is fine and dandy at full throttle with a hot engine, but part throttle conditions cause it to run unemulsified. To fix that, you need to throw out a disproportionately more amount of fuel, in hopes that enough gets vaporized. Hence, the lousy fuel mileage you usually get with a Dynojet kit... -JW:>  | ||
| Ara |
Thanks, Jim. Seems as though I've inadvertantly done the right thing. :-) But here's the odd thing: I've never gotten less that 57 mpg with the Dynojet emulsion tube and #205 main jet, and have gotten over 60 mph on several occasions. Blake has told me that you're not on the main jet at normal throttle openings, though, and I'm not a particularly agressive rider. Russ | ||
| Littledog1 |
Russ, I consistently get 45 mpg on my '98 S-1 running #45/#190 jets, .110" hole in the slide, and a 1988 XL1200 needle, shimmed .009", and air bleed currently 2 turns out. My bike starts instantly, off choke in 30 seconds, has gray plugs (although I think this ignition will burn anything), and smooth power delivery up to rev limiter cut out. Are you getting smooth power throughout the range AND getting 57 mpg? How is your starting and warm up? Any downside? Mickey | ||
| Ara |
Hey Mickey. I don't have any problems at all. I prime the carb with one twist of the throttle, and it fires immediately. I go to half-choke when I get on and no-choke once I'm rolling. Grey plugs. Smooth power, yes, and plenty of it. No downside that I have ever been able to identify. I'm interested in what change in fuel economy I'll see by going to the stock emulsion tube and #195 jet. I'm going out to the H-D shop today to buy a #190 jet on Blake's recommendation. Won't put it in until I get mpg data on this set-up. Believe me, I was astounded by my fuel economy with the Dynojet emulsion tube and #205 jet. Thought it was a fluke until I got several 61 mpg figures and one 63. I liked it. With gas selling at the elevated prices, if the new set-up produces inferior mpg figures and the rideability is the same I'll be real tempted to go back to the Dynojet parts. Gotta run through a few tanks of gas to see. | ||
| Littledog1 |
Russ, If I could get in the 50's I'd go back to the small tank, I prefer the looks. I'll be waiting for your report. Mickey | ||
| Davefl |
Help!! Can someone with a service manual for a 1999 S3 or X1 tell me what a trouble code of 48 is? I have a book for a 2001 model and it is not listed. Thanks in advance Dave | ||
| Anonymous |
There is not a code 48. Are you sure it is not 44, Bank Angle sensor? | ||
| Davefl |
I had a 44 code. Replaced the Bank Angle Sensor after going thru the trouble shotting guide in the manual. Bike still did not run right after sensor replacement and check engine light came back on after a short ride. Now I have a two codes in the system 48-new(and before someone else says their aint no code 48 I have checked and recounted several times) and a code 44- history(according to the manual it will stay in history for 50 run cycles). | ||
| Davefl |
Took the bike in to the shop and they broke out the “Digital Technician”. They say the O2 sensor is giving bad readings and that is my problem. Apparently that was causing weird codes in the ECM. I will not know for sure until I change the O2 sensor. Dave Zephyrhills FL | ||
| 99x1 |
Replaced my O2 sensor yesterday, cured slight surging and seems to pull better between 2500 - 3000. Showed the used O2 sensor to a (respected) auto mechanic - he immediately said I had a coolant leak - the silicones in the antifreeze cause it to go white.  After explaining Buell's are air-cooled, he guessed that silicone gasket stuff was used in the engine at some point. The silicone contamination will make the engine run lean (thus surge). He said most cars show a light brown on the sensor - Has anyone looked at a '99 sensor? (They are mounted closer to the exhaust port then later years (I think), and may run hotter / whiter?) TIA; John | ||
| 99x1 |
Found this after posting the above message:  from Walker Sensors John | ||
| Pj1 |
over the winter I installed a Force intake and changed my slow jet to a #45 and left the fast jet at #195 on my 2001 M2. After riding it a few times I have noticed that the low end torque of the bike is gone and the gas mileage has dropped off considerably. The bike runs much smoother through the RPM's, but has lost it's pull. Any Ideas? | ||
| Ara |
PJ1, I've got the #45 and #195 combination on my S3 and it runs terrific with exceptional fuel economy and throttle response. Any chance you might have accidently bumped the float out of adjustment? | ||
| Reepicheep |
PJ1, take a close look at the intake seals, it is easy to fold one over or not get a good seal when re-installing the carb. This will make the bike run lean, which is a good way to burn a valve. | ||
| Pj1 |
I went back into the carb yesterday just to double check everything and things appeared to be fine. Maybe I will take it off afterwork today and re-check everything again. Is there anything else I should look at once I have it apart? | ||
| Bomber |
check the condition of the slide rubber . . . .easy to mis-install | ||
| Mark_In_Ireland |
I'm thinking about bidding on this item...the buyer says it will fit on my 98 S1 but is unsure about jetting. Is this a good buy? http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&item=2411091287 | ||
| Ezblast |
Anyone running the Quicksilver double pumper yet? Got Thump?! Just Blasting on the Dark side! EZ | ||
| Sickquad |
What's up guys. I have a question about my 2000 M2. I am about to install the Buell race kit (exhaust, air cleaner and ignition box). My question regards jetting. Does anybody know of a good resource for me to look at while I am jetting my bike? Or maybe some recommendations from past experience with this kit? This is my first time jetting a four stroke engine so I am basically looking for a stepwise how to. Thanks Chris | ||
| Josh |
Try this site | ||
| Anonymous |
I recently put a Wileyco cannister, Buell race ECM and Buell race K&N on my Firebolt, fired it up to make sure that all was well and took it into work to have the mechanics zero the TPS. They weren't able to get it to idle, it ran ratty as can be and was running way, way too rich. I took it home and put on the stock ECM and it runs fine. My questions are: 1) can I run this set up without the race ECM until I attend Buell School and can do this myself? 2) the race ECM was manufactured 1/27/03 and is this consistent with the batch of bad ECMs that I've heard about? and 3) are these symptoms of a failed ECM or sensor or did they just botch the job horribly? Thanks in advance. | ||
| Blake |
Anony, They may need to adjust the AFV back to 100. They should know that. The problem could be either inept technician work or a bad ECM. If you don't get any pinging/detonation, your stock ECM should be fine, just not optimum for peak power. | ||
| José_Quiñones |
AFV is adjusted by the computer as the bike runs, you can set it back to 100 all you want but it will change the moment you ride the bike based on what the sensors tell the ECM about how the bike is running. It sounds like you either have a bad Race ECM or they did not properly tell the Race ECM where zero throttle really is, or "zero the TPS" Hope this helps. | ||
| Blake |
The ECM does not adjust its AFV instantly. It uses a time averaging algorithm to avoid major fluctuations due to false indications and brief intermittent changes in ambient conditions. Why do you think the manual calls for running the bike at the appropriate engine speed for a few miles to allow the AFV to self calibrate? If anony's bike was simply started and not run-in appropriately, the AFV would not have had a chance to self adjust and the bike could run poorly. | ||
| José_Quiñones |
Yes that's true, but how would you know that 100 was the right value? My point is that if the TPS and all the sensors and the static timing are correct, the AFV value will be correct based on how the bike is running. Resetting the AFV is treating the symptom not the cause. Check the TPS, the static timing, and the ECM, the AFV will take care of itself. | ||
| Blake |
On a brand new, freshly installed ECM, the AFV is as yet completely uncalibrated and may be too high. If a bike that was running fine then runs terrible with a new ECM and the TPS calibration is correct, checking/resetting the AFV is a valid diagnostic concern. The suggested initial value of 100 for initial AFV comes from multiple sources in a position to know such things. I don't know if it is referenced in the XB9 service manuals or not. I have heard of quite a few instances where an initial TPS reset, though it seemed to go per plan, did not yield good results and a second/subsequent TPS reset was required to get the engine running well. That would be my first suspicion, that anony's bike simply needs another TPS reset performed. I thought he had said that they tried it more than once, but in rereading his post that is not clear. I don't understand the willingness of any tech to let a bike that is not running properly out of the shop. Anony, Do you need the Buell school to be able to reset the TPS? The following is from XB9R service manual...  |
