Gen 2 2008 secondary throttle position sensor adjustment

[eskimo619]

Hey everyone, so im in the middle of checking/adjusting the secondary throttle position sensor. Reason being is that I accidentally adjusted it thinking it was the main throttle position sensor. I put it back roughly to where I thought it was and never got any type of check engine code. But figured why not see what the voltages were with the plates fully opened and closed. So fully open it was reading around 4.67v. Closed was almost 0.7v. From an online manual I found based on a 2007 model it states fully closed should be 0.6v and fully open 4.5v. Ive set fully open to 4.5v and fully closed is almost right at 0.6v. Ive also read some forum posts that state fully open should be more than approximately 4.38v. So it safe to say anywhere between 4.38v and 4.5v is acceptable? Here's a few pictures of the manual info ive found. Want to be certain before putting the bike back together.

Also has anyone personally removed their secondary throttle plates? Ive read some conflicting info about some having bikes run better without them and others say don't touch them. Thanks!

[Seeker]

Originally Posted by eskimo619

Also has anyone personally removed their secondary throttle plates? Ive read some conflicting info about some having bikes run better without them and others say don't touch them. Thanks!

they are there to make the bike's response to the throttle smoother. If they were not there and you grabbed a handful of throttle, the inlet vacuum would drop (the incoming air speed would drop) but the throttle position sensor would tell the ECU to give the injectors more fuel - the engine would stumble or worst case stall because the air/fuel mixture would be wrong.

The secondary valves intervene to reduce this effect.

Can't help you with the voltages though.

[eskimo619]

Originally Posted by Seeker

they are there to make the bike's response to the throttle smoother. If they were not there and you grabbed a handful of throttle, the inlet vacuum would drop (the incoming air speed would drop) but the throttle position sensor would tell the ECU to give the injectors more fuel - the engine would stumble or worst case stall because the air/fuel mixture would be wrong.

The secondary valves intervene to reduce this effect.

Can't help you with the voltages though.

I do understand their function and makes sense. Whats odd is the reports I've read that people stated their bike ran better both low response and upper after deleting them. Im trying to cure some low end stumble spots and figure id start with getting the stp back to spec. Already adjusted the tps. Havnt done the throttle body sync as I dont have the tool. And for some reason the high idle has never functioned since ive owned the bike which is a short time. Still runs pretty well overall. Just chipping away at getting things back to spec.

[Craig380]

I've never removed mine, but read plenty of posts from those that have. In a lot of those cases, they end up reinstalling them for general smooth running and better manners on the road.

On a track bike there's probably a benefit in removing the STV plates because you don't care about small throttle openings and you don't want the ECU interfering when you demand WFO throttle.