| Author | Message | ||
     Jmartz |
Jim: I have converted my '96 S1 to SF. You will have to endure a heavier coil and and extra wire to power it and an extra wire to the tach so it works right. It will cost dearly, well over $400. Benefits, trick factor of course, slightly better throttle response below 3000 rpm. There will also be some spark curve building (or selecting) and tuning (+ or - around Zero) required. Worth it? Humnnnn... only if you are running higher compression/hotter cams/porting so you can optimize the motor with an adjustable ignition module from which single fire will be byproduct. Jose | ||
| Jiml |
Aaron & Jose, Thanks for the info. I'm thinking now of just setting back and taking a let's think about this a little more. later, jiml | ||
| Aaron |
Okay, somebody who's a whole lot smarter than me just got me to think this all the way through ... you guys tell me if I'm full of it here ... When the rear cyl hits, where's the front cylinder? Is there any fuel in it to burn? Seems to me that, assuming 35 degrees of advance, the front is 80 degrees from tdc on his exhaust stroke (just past halfway through it). I can't imagine there's anything in there to burn. What about when the front cyl hits? Assuming the same 35 degrees of advance, the rear cyl will be just 10 degrees past tdc on it's intake stroke. Hmm ... in a mildly cammed motor, there's probably nothing in there to burn. The first 10 degrees of crank movement barely moves the piston at all. But what if the cams have a lot of overlap? And the exhaust system is giving a good yank right then? Absolutely, you may have fuel in there already. That's the whole idea of overlap, give the intake charge a head start. So maybe that wasted spark does cause a problem under this scenario. It would be interesting to test single & dual fire back to back on both a mildly cammed stock motor and cammed up motor with a good exhaust and see if the results varied. I wouldn't be at all surprised to see the cammed motor respond much better to single fire. See ya, AW | ||
| Sparky |
Aaron, I'm with you. The scenario you described was the subject of several articles by Joe Minton years ago advocating the development of aftermarket single fire ignitions. His theory was that the stock ignition on a slow turning big twin running a cam with a fair amount of overlap would cause a reversion of the front intake charge. This would happen when the rear cyl fires because a small amount of mixture could ignite when the front intake is opening. His demonstration was to watch the fuel standoff at the mouth of the carb when the throttle was whacked open. Often it would pop and backfire out of the carb. He suspected this reversion or back and forth flow through the carb would cause the front cylinder to be either leaner or richer than the rear depending on severity of reverse flow. This might explain why our plugs don't always look the same color. I rough graphed the valve and ignition timing in Excel some time ago for an Andrews 46 cam and 35 degrees timing. Sure enough when the rear fires, the front valve is around overlap & ramping up, and 'stuff' can happen. Let's see if this works.  So a single fire ignition may help an engine run smoother at low to medium speeds by reducing front intake reversion but I wouldn't expect to see dramatic increases in horsepower. Sparky 96S1, 98S3 | ||
| Sparky |
I goofed it. Should look like this:  Ya can't fool with uploaded files! Sparky | ||
| Aaron |
Sparky: That's a great chart, and it really illustrates things well ... but, unless I'm missing something, the F and the R are inverted for all the lines, i.e. everywhere it's referring to the front, that's the rear, and vice versa. Simple way to see this ... we all know the firing spacing is 405 degrees, followed by 315 degrees, followed by 405 degrees, right? You can see this in how the firing lines are not evenly spaced. But, isn't it 315 degrees from the front firing to the rear firing, and 405 degrees from the rear firing to the front firing (the chart shows the opposite)? I think it has to be. The front reaches TDC 45 crankshaft degrees AFTER the rear does. So it's only 315 degrees from there to the rear TDC. That's why I'm saying the rear gets lit on the overlap by the wasted spark when the front fires, and you're saying it's the front that gets lit on it's overlap by the wasted spark when the rear fires. Or something like that. My head hurts  . Whaddya think? AW | ||
| Sparky |
Aaron, I think you're right. After looking at the data again, I can see where I assumed that the rear events would be 45 degrees later not sooner, which is not true. The answer is in this picture I'm sure but it moves too fast to match my comprende speed  . I'll redo the chart tomorrow and we'll see what's happening. Sparky | ||
| Sparky |
Let's try this again. Server error. A picture is worth a 1000 words:  Sparky | ||
| Sparky |
Updated timing chart. Seems to show what Aaron was saying, "the rear gets lit on the overlap by the wasted spark when the front fires." Andrews EV 46 has 246 deg duration and 42 overlap. This is comparable to the Big Twin Screaming Eagle Bolt-in cam which has 244 In, 250 Ex duration and 35 deg overlap. If these SE specs also apply to the Lightning cams, then this chart is representative of what's happening in our Lightnings & S3's. If not, it's probably close enough for our purposes, eh?  Sparky | ||
| Treich |
Hello All! I'am a newbe to all that goes on in the world acording to Buell. (just bought a 98 S3T) so far it's a blast (no not the model). Here's the question. How do you time them? Mine seems to be to far advanced as it is backfireing through the carb once in a while at around 3000 rpm at cruise. The bike has had nothing done to it (YET). Any thoughts? Thanks in advance. Tony | ||
| Jmartz |
Treich: I doubt your engine's misbehavior is timing related. Carburator backfires are due to momentary lean conditions due EPA forced factory settings aggravated by intake/exhaust mods. Open the slow jet some more, followed by changing it to a larger size, followed by lifting the main needle in .020 increments. It will be cured, believe me! Jose PS Make sure there are no intake manifold leaks or the procedures above will not work properly. | ||
| Aaron |
I'm with Jose. Take a look at this tech tip on ATC's site, it works really well. And, like Jose sez, check or just change your intake mainfold seals while you've got the carb off. I'm betting your little problem will disappear. AW | ||
| Treich |
Thanks alot I'll Try it this week. Happy Buellin it's going to be 75 deg this week here in AZ!!! | ||
| Stage1wd |
to anyone, i have a 00 X-1 with a vance and hines ss22r slip on. it ran fine with this. i added a K&N filter and a buell race ecm and now it pops and backfires. it does not seem to even want to hold an idle when hot. has anyone had experience with these modules??? do they have to be flashed for the slip on and filter??? stage1wd | ||
| Eeeeek |
Did you install the ECM yourself? After you install the ECM, you need to have the TPS zero'd or the ECM has no clue whwhen it should actually be squirting gas and such. It's kinda like putting in a new distributer without marking where top dead center is. Vik | ||
| Drandall |
Stage1wd, Eeeek is correct. I had to ride my '00 X1 to the dealer after instlling the race ECM, and it ran very poorly until the tech zero-ed the TPS (throttle position sensor). Make sure the tech knows to read the output of the TPS on the scanalizer until it shows Zero, and doesn't just guess. | ||
| Stage1wd |
Eeeeek & Drandall, thanks, i greatly appreciate your help in this issue. you saved me a lot of aggrevation (and poss $$$$). we will see how it goes. stage1wd | ||
| Drandall |
Stage1wd, If you're still are having problems, Buells are known for being built with poorly installed manifold gaskets. | ||
| Bigblock |
Has anyone been able to add an aftermarket ignition to the injected bikes, or found a way to change the stock timing specs on them without hurting the fuel side of the equation? The Power Commander only tweaks the fuel side of the equation, and the motor I'm building will need a different advance curve than stock(less total timing) Thanks...Ray | ||
| Fastback69 |
What's the best way to check timing? Since there are not timing marks, how do you tell how far advanced/retarded the timing is? | ||
| Aaron |
Your Cyclone has timing marks, both on the timing plate and on the flywheel. You can set it with a timing light, although it's a real PITA in my opinion, dual fire makes it hard to see what's really going on. And then, if you do manage to accurately get it on the factory specified setting, is that what the motor really wants? Not always. My preferred method is to use a dyno. Turn the plate until you get the biggest number. Easier and more accurate. Injection is a whole different deal, that timing plate affects much more than just ignition timing and moving it away from the correct setting really screws things up from what I hear. Ray has a damn good question to which I have no idea. AW | ||
| Fastback69 |
Thanks AW. I plan to get it dyno-tuned after I pass 5000 mi. anyway. What about the dual fire makes it hard to time? I guess the light would pick up both firings so every other flash would be the actual timing signal. Which cylinder is no. 1? | ||
| Aaron |
Yep, you got it, too many flashes and only half of them apply. You'll see when you try to do it, or rather you won't see. It's difficult to see those little marks on the flywheel. More difficult yet if you use the little clear plastic timing plug that HD sells for this purpose, but the alternative is an oily blast of air in your face. The marks are indicative of the front cylinder's position. Good luck, AW | ||
| Ducboy |
HELP..... regarding a 00-M2, i am istalling different bodywork which requires moving the ignition module and I want to mount it upside down. ditto with the little block that contains 2 relays and 2 diodes. does anyone know if there is any circuitry within these pieces that tells the bike "shut off because you are upside down" i sort of remember that there is such a switch somewhere on the bike that does this. | ||
| Fastback69 |
spark plug cross reference Here is a cool site with several cross-reference charts for spark plugs. | ||
| Lars |
Cross Posted to ATC web site, mea culpa . . . Posted by Lars on : Hey all, am wiring in a new Hi4 system on my 98 S3T and had a question. I know where the red white and black wires go. There are two other wires. A Green and a Brown. One can go to the VOES and the other can go to the tachometer. The instructions aren't very clear on the necessity of using the brown and green wires. It says if you don't use them, to tape them up? Do I need to wire to both the VOES and tach or one and not the other. (I noted from Jose's post on Jan 29 that I will need to wire the tach.) What about the VOES? The other question is this: If two Buells left opposite sides of the country @ 0600 local time, and one had a tail wind of 40 knots and the other had a head wind of 15 knots; at what point of their respective journeys would they meet up and which one would get stuck paying the tip at the diner? Thanks a lot! Looking forward to the answers! It's possible that there could be a prize for the most origional answer to question #2 . . . Lars ATC #544, 98 S3T FLY HARD - RIDE FAST S&S, Kooks, K&N, Andrews, C. Martin Custom Machining , Thunderslide/Rejet, Crane, Oil-lite Bushings, 80/100 Lamp (the better to see Moose with) Zero Gravity, etc. | ||
| Tonyinvabeach |
Question on the new bulletin. I just checked my 2000 M2 and no blue sheath on the ignition module wire...which I believe means I don't have the updated ignition module and temp sensor..although I did buy the bike last August. I don't ride all out that much but as summer approaches, and man does it get hot here, am I going to cook my motor? Would it make me any money to go now to the 10R12's and maybe change the main jet? Or, do I only need to sweat this if I'm racing the bike. I'm counting on this bike for some serious mileage so if this is something worthwhile I may go with it. thanks Tony | ||
| Ducboy |
Tony Here"s what i happen to think, but i'm not sure if its 100% truly the case: Buell has taken these measures to protect the air-cooled v-twin from the incessant flogging that insensitive riders, used to bullet-proof liquid-cooled japanese machines, are likely to give it. If you are a careing sensible rider don't worry about it. but, as for re-jetting, going somewhat richer and using the colder plugs will always be safer and if you are hearing any pinging, you need to do it. | ||
| Tonyinvabeach |
Ducboy, Thanks for the advice...kinda what I was thinking. I am hearing something similar to pinging at full throttle (only at full throttle) with the bike fully warm. Sounds like ticking but not the usual marbles sound I usually associated with detonation. Rarely happens. Some folks, on the net and guys I know, have told me this is probably pre-ignition detonation and not that big a deal. But, I thought all detonation was bad. Anyway, I'll see what happens this summer...thanks again for the advice. Tony | ||
| Jph |
Hi Any of you good people got a copy of a Battle2Twin magazine that did a story on ignition curves for the Buell?? Can someone please scan and send me that article?? Thanks Paul |
