Feul Injection and Altitude Power Loss

[MattTLS]

So I'm curious.. does anyone know how the volume of air being fed into the intake is measured on modern FI'ed motorcycles?

I'm no expert, but I don't know of any bikes currently using a mass airflow sensor. However, some are now using an O2 sensor in the exhaust (VFR800 and a Buell ?? I think) in a closed-loop, self-adjusting system. Most FI bikes' systems are composed of sensors measuring intake air pressure, crankshaft position (rpm), and throttle position (along with various other sensors which compensate for differences from the 'normal' conditions) which are used to determine the injection duration/amount of fuel.

Matthew

[dr1ft3r]

I'm no expert, but I don't know of any bikes currently using a mass airflow sensor. However, some are now using an O2 sensor in the exhaust (VFR800 and a Buell ?? I think) in a closed-loop, self-adjusting system. Most FI bikes' systems are composed of sensors measuring intake air pressure, crankshaft position (rpm), and throttle position (along with various other sensors which compensate for differences from the 'normal' conditions) which are used to determine the injection duration/amount of fuel.

Matthew

Matt,

You're right about the Buell XB9R and XB9S. My co-worker rides one and when I was pondering this a couple weeks back, he actually went through his owner's manual and found the part that references to the existence of an O2 sensor in the exhaust. The real world test would be to see how well the closed-loop system adjusts itself when moved from Denver to say Houston compared to a non-closed-loop FI system when doing the same move. Gotta love the competition among the different manufacturers. Us consumers are reaping the benefits of continued technological strides year over year.

James

[Solinary]

Hello,
I just recently returned home to Denver from Alaska (sea level), and I was wondering where the best place to take my bike would be to get a tuneup. I have definatly seen a loss in the bikes over all power as well as a couple other anomolies, such as a sag on quick hard acceleration, and would like to get her back in top shape. I would appreciate any suggestions for a reputable shop. Oh, and I am on the Littleton side of the state if that helps.

[Hoopty]

http://www.tfogracing.com/

[Anonymous]

http://www.tfogracing.com/

Yes, TFog comes recommended by one of the local racers (plus some other members). They're located in Golden, near where 6th Ave. hits I-70.