Dyno's my bike....

[OKCVmax]

Well... I had my bike dyno'd tonight.

The operator said it's running lean, pretty much everywhere... and that I should bump it up a jet size to get it where it should be. What do y'all think? It's stock as far as I know. I'm at about 1200 ft above sea level.... (don't know if that makes any difference though)

 

[OKCVmax]

Title was supposed to say "Dyno'd* my bike" not Dyno's lol.

 

[Traumahawk]

Well first of all, your gonna have to get into the carbs and see if the PO changed any thing....IE jets, float level height.....etc. Then you can decide on where to go from there. I will tell you one thing, a stock Vmax isnt supposed to be that lean.

 

[OKCVmax]

Well first of all, your gonna have to get into the carbs and see if the PO changed any thing....IE jets, float level height.....etc. Then you can decide on where to go from there. I will tell you one thing, a stock Vmax isnt supposed to be that lean.

Ok. That's what I was thinking. Gonna try and get it apart today if I can.

 

[OKCVmax]

Ok... Main jets, stock. Needles, stock. Float level, correct (slightly rich on two carbs actually, I adjusted to correct level).
The boots that the carbs slide down onto have a few cracks but none go past where the hose clamps seal it off. I sprayed starting fluid on/around them while it was running with no RPM change, so I don't think they are leaking. Still going to order replacements though.

Any ideas???

 

[Traumahawk]

Well i was just chatting with a friend of mine. he had 2 ideas. How for was the probe inserted into the exhaust? He was wondering if you could get a false reading if the probe is too deep.

He also mentioned that when the A/F sensor starts going bad, they will start reading lean. Actually where he works, thats how they know that the A/F sensor is starting to go bad.

If everything is stock, and the floats were slightly rich (which is about equal for every other stock Vmax), you shouldnt be getting readings at 14+.

How does the bike run? Does it stutter when its cold, or hesitate, that gets better when it gets warmer?

Where was the dyno done? Do they dyno a lot of bikes that are rich? On my A/F meter, the richer you are, it will "wear out" the sensor faster. Also on my set up, you also check the A/F sensor each time prior to use......to make certain that it is within speck.

 

[Traumahawk]

I was curious so I went back and looked in My LM-2 manual, about calibrating the sensor. This is what it said.

2.3 Calibration Schedule
Normally aspirated (daily driver)
- Calibrate before installation of new sensor
- Calibrate new sensor again after 3 month of use
- Thereafter calibrate once a year or every 20,000 miles, whichever comes first
Turbo Application, daily driver (tuned rich)
- Calibrate before installation of new sensor
- Calibrate new sensor again after 3 month of use
- Thereafter calibrate twice a year or every 10,000 miles, whichever comes first
Race Application
- Calibrate before first installation of new sensor
- Calibrate once per race weekend
- For added sensor life we also recommend our optional double length bung (part
number 3764
Dyno use:
- Calibrate a new sensor
- Calibrate every 2-3 days, depending on usage

 

[OKCVmax]

He had the probe in as far as he could get it (which wasn't that far, I guess it wouldn't go past a certain point).

When cold it does hesitate slightly at lower rpm, but after a couple of minutes running it goes away.

It was done by chris huckeby down in Moore, OK. From what I've read he's pretty good...

I would assume it was working. While there he pointed out where the bike starts to go "leaner" at about 7k the power drops. I don't know if that's just a coincidence or what....

 

[OKCVmax]

Here are the spark plugs.

 

[Traumahawk]

The plugs dont look like your running that lean.

About 7 k on a stock set up bike is when Vboost is fully in, and it still shouldnt be going that lean.

Here is a comparative dyno, between stock (well I had slip ons), and seans jet kit, and a kerker 4-1. Hp was still down a bit due to the wheel I was running.

On mine, I have Vboost coming fully open at 6 K.

 

[OKCVmax]

Yeah, I'm not sure why it's running that lean. I ordered new rubber boots for the bottoms of the carbs since my old ones are cracked (I just want to eliminate anything that it could be)

Also, I'm getting about 33 mpgs... which seems about average from what I've read (or is it?)

My only other idea would be going up a main jet size to see what happens, but I just don't know if that's actually my problem....

 

[OKCVmax]

And yeah, I agree about the plugs. I didn't think they looked that bad.

 

[Traumahawk]

Yeah, I'm not sure why it's running that lean. I ordered new rubber boots for the bottoms of the carbs since my old ones are cracked (I just want to eliminate anything that it could be)

Also, I'm getting about 33 mpgs... which seems about average from what I've read (or is it?)

My only other idea would be going up a main jet size to see what happens, but I just don't know if that's actually my problem....

33 is about average for a Vmax.

Is the airbox fully seated? "Y" still on, doesnt have holes drilled in it?

Carb boots that are cracked on the outside, isnt an issue (because are they cracked on the inside? Thats an issue. )

If you were running that lean, your plugs would be bone white

 

[OKCVmax]

Yup, airbox s fully seated, no holes in lid or Y, no spacers under the Y.
Some of the cracks do go all the way through, but none of them go past where the hose clamp grabs the boot and seals it on the carb. Maybe there's one I'm not seeing.

It should be making more than 103 hp though, right? What's with the wierd drop in hp at about 7k rpm?

 

[Donny Daughtry]

Here are the spark plugs.

From the looks of those certainly is time for a change-:eusa_dance:
If you are falling off at 7000rpm your mains need to be larger.:clapping:

 

[Traumahawk]

Yup, airbox s fully seated, no holes in lid or Y, no spacers under the Y.
Some of the cracks do go all the way through, but none of them go past where the hose clamp grabs the boot and seals it on the carb. Maybe there's one I'm not seeing.

It should be making more than 103 hp though, right? What's with the wierd drop in hp at about 7k rpm?

Yes it should be, but yours is stock.....right? Mine only made 104.49

Conners was only 108.

Also a Vmax doesnt usually make best hp until the 5th or 6th run. You basically run them until the hp drops off.

That did could have something with Vboost opening.

https://www.youtube.com/watch?v=i5wuY1SNkXw

 

[OKCVmax]

Yup, it's bone stock. So could be sone thing with the vboost not opening correctly? Or is that normal?

 

[SpecOps13]

Your plugs look like they've been in for some time or exposed to the weather but they appear fine to me for an average. Nearly perfect by my standards.

 

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I'd question the validity of those AF results. Plugs look good. Bike is making average power for stock. According to your description, it sounds like it runs normal.



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[OKCVmax]

I'd question the validity of those AF results. Plugs look good. Bike is making average power for stock. According to your description, it sounds like it runs normal.



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That's what I'm starting to think. I don't think those numbers are correct.