01 Fuel Injection question

mtbrights · 11-08-2008, 07:13 PM

My o1 has a slip on Two Bros muffler, otherwise stock. I bought it used this spring (19K) and ran it this summer. It runs rougher at 3-4k than I would think it should and the bikes midrange is (very) flat until 6500-7K when it runs nice and clean. Throttle response is also difficult to manipulate in parking lot situations. on/off etc...

I suspect it's running lean until the 6500 RPM level, because it's like flipping a light switch, but don't know what the algorithm looks like for the stock fuel injection. I've searched for threads in this regard but haven't come across this particular problem on this board.

I may have to resort to Dynojet but I would prefer to rule out any potential FI problems beforehand. Any thoughts.

Edit: No codes flash on the FI light.

maddog · 11-08-2008, 08:51 PM

Are valves within spec?

Are plugs good?

is air filter clean?

Have the starter valves been synched?

Clogged injectors, from sitting idle, could be a problem.

I'd lean toward the starter valves needing to be set.

mtbrights · 11-08-2008, 10:21 PM

I checked and replaced all the above myself when I got it except for the starter valves. SO I will try to check them tomorrow and let you know. Thanks for the tip.

mtbrights · 11-14-2008, 07:18 PM

Maddog had it right as the starter valves were off on three and four. Much smoother throttle response and runs much nicer. I didn't realize I didn't even have to take the air cleaner off. I just tapped into the hoses on either side of the air cleaner with the homemade carb syncronizer I built as outlined on this site also.

Pretty fruitful day for me thanks to this site.

kingsley · 11-15-2008, 12:26 AM

Another happy customer! I read somewhere the starter valves are only in use for the first 4% of throttle, then have no effect.

But they seem to have a lot to do with the overall smoothness through the RPM range. Easy tweek with the home made manometer.

I synced mine with PAIR enabled (contrary to manual, from a detailed thread I read elsewhere) as that is the way it will be running normally.

mikeym · 11-19-2008, 01:44 PM

Quote:

Originally Posted by mtbrights

Maddog had it right as the starter valves were off on three and four. Much smoother throttle response and runs much nicer. I didn't realize I didn't even have to take the air cleaner off. I just tapped into the hoses on either side of the air cleaner with the homemade carb syncronizer I built as outlined on this site also.

Pretty fruitful day for me thanks to this site.

Could you give me a run down on how to check the starter valves? I'm not even sure what they do....

Thanks...

kingsley · 11-21-2008, 04:02 PM

Quote:

Originally Posted by mikeym

Could you give me a run down on how to check the starter valves?

You can find it in the free download-able service manual (got mine off VFRD)

Google "homemade manometer" for ideas if you're going to build your own.

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11-08-2008, 07:13 PM	#1 (permalink)
mtbrights Junior Member Join Date: Oct 2007 Last Online: 11-25-2008 09:16 PM Posts: 11 Thanks: 0 Thanked 0 Times in 0 Posts	01 Fuel Injection question My o1 has a slip on Two Bros muffler, otherwise stock. I bought it used this spring (19K) and ran it this summer. It runs rougher at 3-4k than I would think it should and the bikes midrange is (very) flat until 6500-7K when it runs nice and clean. Throttle response is also difficult to manipulate in parking lot situations. on/off etc... I suspect it's running lean until the 6500 RPM level, because it's like flipping a light switch, but don't know what the algorithm looks like for the stock fuel injection. I've searched for threads in this regard but haven't come across this particular problem on this board. I may have to resort to Dynojet but I would prefer to rule out any potential FI problems beforehand. Any thoughts. Edit: No codes flash on the FI light. Last edited by mtbrights; 11-08-2008 at 07:41 PM.

11-14-2008, 07:18 PM	#4 (permalink)
mtbrights Junior Member Join Date: Oct 2007 Last Online: 11-25-2008 09:16 PM Posts: 11 Thanks: 0 Thanked 0 Times in 0 Posts	Got it figured out Maddog had it right as the starter valves were off on three and four. Much smoother throttle response and runs much nicer. I didn't realize I didn't even have to take the air cleaner off. I just tapped into the hoses on either side of the air cleaner with the homemade carb syncronizer I built as outlined on this site also. Pretty fruitful day for me thanks to this site.

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11-08-2008, 08:51 PM	#2 (permalink)
maddog Member Join Date: Dec 2007 Last Online: Today 11:04 AM Location: Idaho My Ride: 2000 Honda VFR Posts: 74 Thanks: 0 Thanked 2 Times in 1 Post	Are valves within spec? Are plugs good? is air filter clean? Have the starter valves been synched? Clogged injectors, from sitting idle, could be a problem. I'd lean toward the starter valves needing to be set.

11-08-2008, 10:21 PM	#3 (permalink)
mtbrights Junior Member Join Date: Oct 2007 Last Online: 11-25-2008 09:16 PM Posts: 11 Thanks: 0 Thanked 0 Times in 0 Posts	I checked and replaced all the above myself when I got it except for the starter valves. SO I will try to check them tomorrow and let you know. Thanks for the tip.

11-15-2008, 12:26 AM	#5 (permalink)
kingsley Senior Member Join Date: Jul 2007 Last Online: Yesterday 11:50 AM Location: Port Coquitlam B.C. Canada - Find Me! My Ride: '98 Viffer - Black View my Photo Gallery Posts: 224 Thanks: 1 Thanked 1 Time in 1 Post	Another happy customer! I read somewhere the starter valves are only in use for the first 4% of throttle, then have no effect. But they seem to have a lot to do with the overall smoothness through the RPM range. Easy tweek with the home made manometer. I synced mine with PAIR enabled (contrary to manual, from a detailed thread I read elsewhere) as that is the way it will be running normally.