Can exh packing effect jetting requirements?

[liptoss]

I may have missed it in this thread, but... just a thought:
Beyond proper jetting (idle, mid and wfo) and elimination of flatspots in the rpm range
I haven't yet read of anyone utilizing other indications of too rich or lean combustion. Those being observing the outlet pipe on the exhaust for excessive "sootiness" or reading the plugs for indication of lean or rich combustion.

 

[caseyjones955]

I've never had a bike that didnt soot up a little bit. I was glad the guy I was riding with spoke up as it has to be pretty rich for him to smell it from that far back, in the hills, with the breeze.
I'm getting the 147.5 and 145 sets coming though. I'm considering building a sniffer to take some of the guesswork out of it.

 

[veebooster]

Get the mains right first then worry about needles then A/F screws. The mains even overlap the lower circuits to a degree.

Dale

 

[caseyjones955]

Its killing me, yesterday and today perfect weather. I put the 145 jets in and there is no place to go. The Sturgis rally looks to be taking off early and the roads are seriously clogged up with novelty bikes, they huddle in large groups and travel slightly slower than a parade float. Throw in a bunch of RVs and you have an accurate picture of it. I'll have to wait another 10 days or so before I can get any meaningful riding in. It seems that ripping through the hills can reveal tuning issues you don't easily see on the biway doing throttle roll-ons.

 

[caseyjones955]

145 Jets installed, needles still on the blunt end. Runs fantastic, I wonder if it might be a touch lean just because they are 145s and needle position. I'm definitely planning to buy or build a sniffer like Eric has.

Every time vboost started making the world blurry I found myself on top of a gaggle of novelty bikes piloted by what I'm pretty sure were refugees from The Village People. Still plenty leftover from the Rally so maybe a few more days before I can really ride. Man you guys are so lucky you don't have to go through this every year. I did get it to redline in 4th going up 44 and there was no hint of stumble or miss and it pulls quite furiously after 5k. I'm getting close to a proper tune. This is really nice. Thanks Eric and Danny for all the help.

 

[Traumahawk]

Glad that the bike is running well. If do do the the innovate hand held recorder like I have, run it to redline in 4th, the recorder can only record so fast, and in gears 1-3 the bike accelerates too quickly.

 

[caseyjones955]

I found a couple schematics for building them. I may have to send wifey to the PI on a family emergency so funds will be short and if I can throw something together that would be great. I have a wideband o2 sensor here, then calibration will be an issue. I thought about doing a permanent mounted 02 ratio meter just because of the extreme altitude fluctuations I see while touring, that and a volt meter would offer some value.

 

[thor_eyerdhal]

Glad that the bike is running well. If do do the the innovate hand held recorder like I have, run it to redline in 4th, the recorder can only record so fast, and in gears 1-3 the bike accelerates too quickly.

Mine works with any gears, very curious..??

 

[Traumahawk]

Re: Can exh packing effect jetting requirements? 4k stumble.

Mine also works in any gear. I'm talking about the record function vs how quickly a vehicle accelerates. In say first gear....due to how fast the vehicle accelerates...there will be a 500 rpm gap...every time it records....but in 4th gear....there is only like a 100 rpm gap.

Understand?

Sent from my SCH-R890 using Tapatalk

 

[caseyjones955]

I would be content to see it real time. All the tourists will be gone soon and wide open roads aplenty, so I could glance at a gauge without landing under an F350. Not sure I can justify the purchase of the sweet handleld as I can only use it on the Max. Even my Sami is EFI.

I may let the needles out a notch just to see what happens.

 

[thor_eyerdhal]

Re: Can exh packing effect jetting requirements? 4k stumble.

Mine also works in any gear. I'm talking about the record function vs how quickly a vehicle accelerates. In say first gear....due to how fast the vehicle accelerates...there will be a 500 rpm gap...every time it records....but in 4th gear....there is only like a 100 rpm gap.

Understand?

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Yes it will be more accurate in 4th or 5th.
But are you sure it can't handle fas accélérations? The rate reading of the sensor is very fast, just look the curve without smoothing it.

What i see on recorded curves is that the AFR value at a given RPM is going richer and richer with higher gears.

 

[Traumahawk]

Re: Can exh packing effect jetting requirements? 4k stumble.

When I used 3rd gear there was between a 300 and 400 rpm spacing on the recording.....so I wanted something more accurate.....so I use 4th gear for recordings. I've only used it for recordings in 3rd and 4th. I don't know about the increased a/f readings in higher gears. I know that engine demands for fuel are higher in the higher gears.

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