| Author | Message | ||
     Hkwan |
I'm talking about just letting the bike cruise in 1st gear without any throttle input from you. My bike seems to jerk a bit when it slows down on its own to certain speed in 1st when I am not applying any gas. It's like when the speed is too slow for certain gear type of jerk. I have to slip the clutch constantly during, say, parking manuvers. My F4i doesn't do that. Is this normal for Buell? Any comment? | ||
| Signguyxb12  |
try bragging the rear brake... works for me | ||
| M1combat  |
That's called lugging an engine. You F4i does it too, but because it's still at a higher RPM and has four pistons instead of two and isn't in a "V" configureation etc, you don't feel it as much. Don't lug the engine. | ||
| Ingemar  |
My 9 does that too. Remember a buell engine has a longer stroke than most other sportsbikes out there. | ||
| Rooster2168  |
What they said, or your primary could be really loose you might want to check that. | ||
| Hkwan |
Let me clarify a bit - I'm talking about when the bike slows down to around 10mph or so on its own in 1st gear (~15 mph in 2nd) and when you don't have any thrttle at all, the bike start to lug/jerk. I know the F4i does it but that's when I really "lug" it, meaning when I apply the brake when it gets down to a very slow speed. Otherwise, the F4i would maintain its own speed just fast enough for it not to lug/jerk. Why can't the Buell maintain a speed on its own fast enough for it not to lug like F4i does? Also, would you think it is too much to ask the Firebolt to do for not lugging @ 10mph in 1st? (Message edited by hkwan on December 05, 2004) (Message edited by hkwan on December 05, 2004) | ||
| Xb9er  |
If you drop below 3000 rpm on these V-twins, it will lug. Just work the clutch or keep it above 3000 rpm. You will get used to it. XB's are not meant to cruise around at 10mph. Mike. | ||
| Joele |
It seems to me that the characteristics of this motor require some rider finesse - use your throttle and clutch to reduce lugging and harshness. You maintain the best control over your bike when things are smooth, including deceleration. | ||
| Hkwan |
OK, got it. Thank you for solving my concern. Above 3000 rpm seems kinda of high though. For sure when the motor lugs/jerks, it was below 3000 rpm. So you guys work your clutch/throttle in the parking lot constantly as well? I wasn't so much of disliking that it won't cruise @ 10mph; I was more concerned that if my primary chain is loose. It just is a HUGE difference comparing to the I4 motor from the 600 sport, that's all. | ||
| Joele |
So you guys work your clutch/throttle in the parking lot constantly as well? Yes - this was actually part of the Rider's Edge Advanced Rider's training. | ||
| Hkwan |
Joele, I pretty much am on the clutch, slipping it, the moment I even come close to a parking lot while I'm on the Buell. On another scenerio - riding on wet road and taking a turn, slowly, with engine @ lower than 3000rpm type situation (I'm talking about even a 15 mph turn seems fast with BUNCH of wet leaves and water puddle on the ground), you guys slip the clutch going into and during the turn? I have to do that to prevent lugging. Do you? | ||
| Joele |
In the case of that turn - you should probably break to a low speed, pick either 1st or 2nd - then gently roll on the throttle during the turn. In extreme cases, hold the clutch in and feather the rear break. | ||
| Hkwan |
"In the case of that turn - you should probably break to a low speed, pick either 1st or 2nd - then gently roll on the throttle during the turn. " That's exactly what I do now or sometimes, I do slip the clutch when the turn catches me by surprise. Now, how is the XB's a "street fighter" when there are so much more work involved when riding around the city/street comparing to the I-4 sport bikes? Not that I'm not enjoying the XB at all, in fact, I enjoy every second of riding it, just that I think Buell can market the bike differently and not set the wrong expectation, that's all. | ||
| Opto |
Yes, I do whatever I have to, to prevent lugging. Keep it smooth, the XB is no sewing machine. Lots of feathered clutch and a few revs when necessary at very low speed is par for course. | ||
| Unibear12r |
Just why do some people think that your lugging when between 2 & 3krpm. Not true. There is a difference between the cough/stumble that occurs between 2k & 2.5k and when your really lugging the engine down around idle. It's easy to hear & feel the difference. My old Sportster didn't do it as bad as my S3 which doesn't do it as bad as my XB12. These engines need REALLY small fuel/air charges to maintain at that light load. Made worse by increasingly leaner burn requirements to meet epa. Has to do with reliably getting the charge to properly burn each engine cycle, not falling off the power curve and lugging. BMW recently had to go to dual sparkplug heads (among other things) to stop it in their bikes. Their riders harped on them for years over it. If the bike was actually lugging it would continue to lug at a reducing rate as you gave it gas and it accelerated up out of the lugging range onto its power curve. Give these bikes a little gas and they smooth out even at the same rpm and very little acceleration. It bugs me but it's a costly production fix for a small problem. If Buell ever goes to dual plugs for more performance they might be able to address the problem.Take a look at Aztec12r's post in the Techlusion PROBLEM!!! HELP!! thread. You are not hurting the bike riding at 2krpm for extended times but you might hurt your pride in a parking lot.  (Message edited by unibear12r on December 05, 2004) (Message edited by unibear12r on December 05, 2004) | ||
| Easyflier |
The only problem I've ever had with either a 9 or 12 in slow turns is when the throttle cables had too much slack and the front suspension was too soft. Then the motion transferred through the wrist made it feel "jerky". Once I tightened them up I was able to maintain smooth power through curves at any speed. | ||
| Hkwan |
OK. Thank you. It's making sense now. And I was reading abouthe BMW's dual plug purpose was to address a more efficent buring of gas mixture and the article (one of those bike magazines) didn't mention the lugging. | ||
| Unibear12r |
Back in the late 90s Harley put a dual ignition on the XL1200S and got what they claimed was 40% more power. Didn't seem that much to me but was a noticeable improvement. Harley said they dropped the model due to low sales. At times they are hurt by their image as helped by it. I remember reading some years back that some automotive engineers were then experimenting with complex dual chamber heads or a second direct fuel injector aimed at the spark plug to get reliable combustion at the lean mixtures that would someday be required. I'm guessing this bike is getting close to needing that to pass epa without a cat. Its been said that the 12s were always intended but didn't come out at the same time as the 9s to spread out production costs. BMW went to complete management of each cylinder including separate O2 sensors and such. I don't think most Buellers would have wanted to pay the high cost of this for such a near non-issue. Its a 15mph zone/parking lot problem most of us avoid like the plague anyway. Who knows if dual plugs will improve power/smothness in the XB. If it does then you might see it down the line as a production improvement to keep up interest in the XBs. And maybe six speed trannys. I'm just a techno-nut looking forward to whats coming next.  | ||
| Xb12scg05 |
The so called jerking and bucking at idle speed is caused a lean mixture which does not allow for a complete burn | ||
| Buellfool  |
My 12S with the race kit runs sweet with no stumbles from 2-3k in any gear (except maybe 5th @2k if you twist the throttle to the stop). It sure does not feel like the motor is lugging at anything above 2k. | ||
| Hkwan |
Well, at 2K rpm, my bike does well as well. I think I had brought up a non-issue. Thank you all for the help. | ||
| Midknyte |
Hkwan, Nuther thing you wan't to keep in mind with this engine, though this is off on a tangent. You're gonna have to get out of the habit of downshifting into a turn (especially into 1st gear - stay away from it once already moving). The engine will not be spinning fast enough and when you let that clutch out you'll get tossed around a bit. Someone pick up here and explain this better than I can... | ||
| Wyckedflesh  |
The gearing jump from 1st to 2nd is enough that if you downshift too soon from 2nd to 1st you will cause the rear wheel to lock momentarily. I myself noticed that as I got past the 5K mileage, the point in the RPM range that stumble showed up got lower. I can go as low as 2K rpm with no stumble. PArt of that may also be the fact I have very little slack in my throttle cables and less then recommended slack in my clutch cable. (1/8th at the lever instead of 1/4) So it may just be that I am makign small adjustments without thinking about them. I also have a bad habit of rolling up to a stop and holding the bike there for a few seconds then continueing on without putting my feet down. Kind of like a trials rider coming to a full stop and just staying up on the pegs, just not as long. One other aspect you might not realise Hkwan, at 2Krpm your Buell is making anywhere from 2-4 TIMES as much torque as that F4i is in the equal part of the revrange. So your feeling those torque pulses more at that slow speed then you did on the F4i. | ||
| Blake  |
A big V-Twin or any twin engine for that matter produce big intermittent power pulses at low engine speeds that make for a very herky jerky ride and a lot of drivetrain vibration. It's what the clutch if for. Good grief. Try riding a big single cylinder bike in the same scenario. It will be like riding a bucking bronco.  Lugging is dependent on two things, engine speed, and throttle position. You can cruise at a lower engine speed without lugging the engine if you use the throttle judiciously. I could cruise at 50 mph in 5th gear if I was very ginger with the throttle on my Cyclone. It's pretty simple, if you feel or hear a lot of unhappy vibration coming from your engine/tranny at low revs, you are probably lugging it and should down-shift or feather the clutch or back off the throttle some. Lugging the engine can wreak havock on a Buell. Don't do it. If you want to ride a cruiser, get a cruiser. And don't expect to ride a V-Twin like you ride an IL4. No twin will be happy running at low rpms, especially those with lighter more sporting flywheels. The twin cylinder cruisers have bigger flywheels and can thus better tolerate lower engine speeds. | ||
| Blake |
The so called jerking and bucking at idle speed is caused by a lean mixture which does not allow for a complete burn. That is highly inaccurate information. Rather, if you ride a Buell at "idle speed", you are purposefully destroying its engine. And a "lean mixture" will better allow a "complete burn" than a richer mixture. An overly lean mixture can lead to predetonation/pinging. That is not a problem on the XB Buells. | ||
| Blake |
Hkwan, Do you own a Buell motorcycle? Which one? When did you purchase it? Do you have an owner's manual? Strange that you don't list a Buell in your user profile. Smells bad to me. I've reviewed some of your other posts on the site. Smells worse. | ||
| Fdl3  |
FWIW, another good example besides "parking lot speeds/manuevers" is school zones. Around here school zones are 15mph. On my XB9R, I have to constantly clutch it to get through these smoothly. If I don't clutch it, the bike is very jerky. I always attributed this to the engine configuration (i.e. 45-degree, large-displacement V-Twin) rather than to some idle/fuel problem. | ||
| M1combat |
The original post states - "when it slows down on its own to certain speed in 1st when I am not applying any gas.It's like when the speed is too slow for certain gear type of jerk. " Uh... Yeah... That's definitely lugging the engine. As Blake said, it's akin to purposefully destroying your engine. Don't do it. Yes, it's "normal" for a Buell to do that. It's "normal" for pretty much any V-Twin to do that. Use the freakin clutch. That's what it's for. | ||
| Oldfz |
When I took the MSF Experienced Rider course a week after getting my 12S, I was having a tough time being as smooth as my classmates who were riding a Daytona, a Vulcan, and a Sportster. The instructor would holler at me when I would try modulating the clutch instead of just idling through the exercises. But you guys are right; in the real world, use the clutch and the bike is a joy. | ||
| Hkwan |
Got it, guys. Thank you. I've stopped doing that. I just don't have much experience with V-twin's that's all. On the downshifting to 1st comment. I usually blip the throttle before shifting into first. Done it with other bikes and have done it with the XB12R. Everything was very smooth, no lock up's. Correct me if I'm wrong, since the bike has so much torque, I think instead of downshifting into 1st, I can play with the clutch and stay in 2nd at times. Blake, what smells bad again? I have the XB12R. I joined this forum before having the bike and I have been owning the 12 bolt for a week or so now. Will update profile. I just don't understand the "smells bad" comment. |
