Airscrew Adjustment to fix off-idle stumble and Throttle Body Sync - w/ pigtails

[jajpko]

Adjusting The Throttle Position Sensor, Page 7-13

Checking The Throttle Position Sensor, Page 8-143

Thanks Tiim

 

[T30]

Just got the bike last week and I've put 225 miles on it. I've had two instances so far of off idle stall. In other bikes (carbureted) that I"ve had this problem was usually cured by bumping up the idle speed. Has anyone try this (by itself) as a fix and if so was it successful?

Also in new to the FI world but hell bent on continuining to wrench on all my bikes. What do you reccomend I buy for working on fuel system for this bike? Is there any particular make model of diognostic device that's recommended?

 

[Karson]

Hey T30 - this is what I used (Harmonizer) by Grok over at advrider. Many say it works like a charm, and I agree. Super easy to adjust the throttle bodies using this tool.

http://advrider.com/forums/showthread.php?t=701625

 

[tomatocity]

The Harmonizer is a piece of cake to use. Plus it is a flash light and beacon.

 

[DuMar]

I did a TBS last year using a home made manometer and initially saw an improvement, but have noticed lately more stumble and hunting rpm. Over winter I bought a Harmonizer and just hooked it up for the first time today. The device showed a +10 to +12 mbar imbalance, and the rpm jumping all over the place. I adjusted the left TB and could here the bike smooth out as balance was achieved. While I was at it, I changed the CO settings on both cylinders (for the first time) from 0 to 5. Initial run around the block shows a big improvement on the bottom end, and what seems like smoother overall running. More testing required to be sure.

One thing I noticed while preparing to connect the Harmonizer: When I pulled the rubber caps off the vacuum tubes on the TBs, there was some kind of liquid substance inside the caps. It didn't seem to have an odor. Does anyone know what this is, or experience the same? ???

Mike

 

[avc8130]

Anyone near North Jersey have a harmonizer and want to demonstrate this awesome tool on my bike? ::003::

ac

 

[tomatocity]

The right side cap had a bit of oily substance and I eventually replaced it.

Next time you raise the fuel tank check the Air Box drain tube. Many of them have oil and water in them. Guessing it comes from the factory that way. Pull the drain tube off, clean it, reinstall it.

 

[DuMar]

The right side cap had a bit of oily substance and I eventually replaced it.

Next time you raise the fuel tank check the Air Box drain tube. Many of them have oil and water in them. Guessing it comes from the factory that way. Pull the drain tube off, clean it, reinstall it.

Thanks, Tim. ::008::

I'll have a look see.

Mike

 

[erenet]

The right side cap had a bit of oily substance and I eventually replaced it.

Were can I get 1/8 vacuum caps?

 

[jajpko]

Any good auto parts store should have them. Or the internet..

 

[DuMar]

I did a TBS last year using a home made manometer and initially saw an improvement, but have noticed lately more stumble and hunting rpm. Over winter I bought a Harmonizer and just hooked it up for the first time today. The device showed a +10 to +12 mbar imbalance, and the rpm jumping all over the place. I adjusted the left TB and could here the bike smooth out as balance was achieved. While I was at it, I changed the CO settings on both cylinders (for the first time) from 0 to 5. Initial run around the block shows a big improvement on the bottom end, and what seems like smoother overall running. More testing required to be sure.

So ... here I am quoting myself after a few days riding and testing the adjustments I made above.

First of all, I feel the CO adjustment (I know this comment doesn't belong here) has made a subtle improvement in the overall smoothness of the bike. ::008::

However, I'm still not happy with the TBS. ::007:: I know others have commented on this and found ECU re-flash (expensive) and PCV (also expensive) virtually eliminate problems at the bottom end.

I can't help but wonder though, if there isn't something else that can be done to smooth out this machine at idle. Just tonight, navigating through a hilly residential construction detour that requires lots of stop and go, the bike gets into one of these rpm-hunting spells in first gear on a steep down-hill with the throttle completely closed! WTF! ::010::

My question is: Is the 270 degree setting on the right TB in the optimum position, or has anyone found a better setting? Or am I barking up the wrong tree? I don't have a lot (read zero) experience with fuel injected bikes.

Any input about what might be going on here, or additional cures, is very greatly appreciated.

Thanks,
Mike

 

[tomatocity]

Were can I get 1/8 vacuum caps?

Use smaller. I think I did.

 

[Cerenkov]

DuMar, I get the impression that CO to 6 and 3/4 turn was the starting point. I've noticed people have been dialing things back in. I went with CO to 3 and 1/2 turn out on the air screws.

 

[tomatocity]

Can someone explain what is to be gained or lost by increasing the CO and Rightside adjustment. I am also at CO = 3 and Rightside - 1/2 turn. I want to experiment for better performance and gas mileage.

 

[DuMar]

Can someone explain what is to be gained or lost by increasing the CO and Rightside adjustment. I am also at CO = 3 and Rightside - 1/2 turn. I want to experiment for better performance and gas mileage.

DuMar, I get the impression that CO to 6 and 3/4 turn was the starting point. I've noticed people have been dialing things back in. I went with CO to 3 and 1/2 turn out on the air screws.

Thanks guys.

Are either of you noticing and stumble at idle or when putting along in first or second gear?

Mike

 

[Karson]

Thanks guys.

Are either of you noticing and stumble at idle or when putting along in first or second gear?

Mike

You might try turning traction control off and seeing if it still stumbles after that, or maybe running in TC-2.

 

[Cerenkov]

DuMar: Sorry it took so long to respond, I only just got my bike buttoned back up and rode it the last couple days.

With CO at 3 and airscrews at 1/2-turn I still get stumble when putting along in 1st. It goes the 8mph with no throttle input that people have reported, but it's not smooth. I'll be tweaking things some more.

 

[DuMar]

DuMar: Sorry it took so long to respond, I only just got my bike buttoned back up and rode it the last couple days.

With CO at 3 and airscrews at 1/2-turn I still get stumble when putting along in 1st. It goes the 8mph with no throttle input that people have reported, but it's not smooth. I'll be tweaking things some more.

Thanks for getting back to me, Justin.

Looks like I'll be doing some more tweaking myself.

Mike

 

[tomatocity]

DuMar: Sorry it took so long to respond, I only just got my bike buttoned back up and rode it the last couple days.

With CO at 3 and airscrews at 1/2-turn I still get stumble when putting along in 1st. It goes the 8mph with no throttle input that people have reported, but it's not smooth. I'll be tweaking things some more.

Me too. Hoping to find a smoother low speed.

 

[Dallara]

~


Just as a quick aside...

An ECUnleashed re-flash of the ECU from AF-1 Racing completely solves any low-speed issues and stumbles. ::008::

Just FYI...

Dallara



~