| Author | Message | ||
     Aptbldr |
Been riding a new-at-our-house '04 SV650, swapping back and forth. SV (stock) responds cleanly and smoothly to changes at its throttle, regardless of situation. I want the mighty XB to do that. Bought my '04 XB12 last July. Came to me with Micron and 'race' ecm installed. I've tweaked its fuel maps and it runs differently than when it arrived (I'd have written 'better' until my perceptions were recently warped by the SV). If I value smooth throttle response, do I want stock exhaust/valve setup? If I set-up to data-log and work to fine-tune the FI, is "smoothness of an SV" a reasonable goal? If I bought American Sportbike's 'maps' matched to bike's mods, will its throttle response satisfy my goal? Experience/advice/opinions? | ||
| Xb1200rick |
I have a 04'xb12 with the same set up you have .Tweeking the maps yielded a little more power sooner which smoothed things a little bit . I have never ridden a sv650 but I have ridden the sv1000. although the HP numbers are similar the sv v-twin is totally different than the xb. The sv is making its power over a much larger span of rpm's since it will rev much higher than the xb v-twin. Our xb's don't come on power good till after 3k and hit the rev limiter at 7k Rick` | ||
| Redbuelljunkie |
There a lot of differences between an SV and XB engine: SV- 90 degree v-twin liquid-cooled double overhead cam four valves per cylinder engine design- late 90's XB- 45 degree v-twin air-cooled push-rod two vales per cylinder engine design- late 50's I do not believe it is reasonable to expect a 52 year old engine design to be as refined as a ten year old one. It is interesting, however, that performance-wise the two are very comparable. I guess it just depends on personal preference- old school character or modern efficiency. | ||
| Aptbldr |
Yes: two different machines. My garage has vee-twin balance; sort of yen & yank. : ) Bore x Stroke, XB: 88.9 mm x 96.8 mm, b/s=-.92; SV: 81.0 x 62.6 mm, b/s=1.29 Compression Ratio, XB: 10.0:1; SV: 11.5:1. Intake, XB: (1) 41 mm; SV: (2) 41 mm. Exhaust, XB: (1) 35.5 mm; SV: (2) 31 mm. FI throttle-body, XB: 49 mm ; SV: 39 mm. Displacement, XB: 1203 cc; SV: 645 cc. Both use different complex electro-mechanical systems to fuel cylinders. That's where my interest lies: can XB approach throttle response of SV? Question, contrast, is not to output, but smooth linear response to throttle changes, fueling/running, across a range from 1000 to 6000 rpm. Overall character of SV, its ergonomics, chassis, and 'soul', don't measure-up to XB for me. | ||
| Jraice |
I have found the only place where my buell could use improvement (stock ECM and intake with a drummer) is in the lug-3000rpm range. Rarely ever there except starting from a stop but getting on it hard it seems to be a little unhappy about being there. Anytime Im upwards of 3000-3500 it feels like power is applied very smoothly. Never ridden an SV but have owned an R6, and those I4's are SMOOTH. | ||
| Tpoppa |
The SV has less torque, that itself may feel like smoother throttle response. My stock XB9 is very smooth on/off throttle. The stock power delivery is extremely linear. The Micron and Race ECM have more power but you lose the linear power delivery (see XB exhaust shootout). If you have the ECM remapped to match the Micron, it will be smoother, but prolly not as smooth as stock. (Message edited by tpoppa on May 26, 2009) | ||
| Midknyte |
Without regard to fuel map fudgery, check the primary chain slack [on the XB]. The amount of slack/play should be equal to about the thickness of the chain itself for a quick reference once the engine is warmed up completely... |
