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Discussion Starter #1
I put my bike on a dyno this afternoon and was. Of expecting the numbers to be so low. Max hp was 82.6 at close to 4500 rpm, tq was 98.15 at 3600 rpm. I have D&D'S, PCV with the stage one download, and I think it's a Vic high flow air filter. Is it just me or should it be putting out a little bit more power then that? I will try to post a pic of the print out if I can.
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Are you riding your Cross Country or a dyno?? How do you like the performance of your bike? That's the real question.

A while back I took my bike to a dyno guy who had come highly recommended, and I was sorely disappointed with the results. Not so much the paper results (although they weren't far off from yours), but my bike was running worse than when I took it in. I watched his entire process of tuning and his sole focus was pretty much mapping my AFR's to stay between 13.5 and 13.0. I was so disgusted with the performance of my bike I threw his map out and started over with a fresh downloaded map. I've since tinkered with it off and on until I've pretty much settled on what I have now, which is nowhere near what he had set it. My bike runs great!! No decel pops, no hesitations, and it will plant you hard back in your seat with just the slightest twist of the throttle. I could care less about what it gets on a dyno as long as it runs like it does, I'm a happy guy.

Lesson learned...the dyno is the dyno...the street is the street.
 

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A while back I took my bike to a dyno guy who had come highly recommended, and I was sorely disappointed with the results. Not so much the paper results (although they weren't far off from yours), but my bike was running worse than when I took it in. I watched his entire process of tuning and his sole focus was pretty much mapping my AFR's to stay between 13.5 and 13.0. I was so disgusted with the performance of my bike I threw his map out and started over with a fresh downloaded map.

Lesson learned...the dyno is the dyno...the street is the street.
I had the complete opposite experince. The bike was super abrupt on/off the throttle at low rpm, it backfired on decel at a certain rpm, and gas mileage was in the 30s. After the tune it runs perfectly, drivability is exponentially better, no pops, and it gets 46 mpg.

So what A/F do you shoot for when you tune it?
 

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Discussion Starter #6
The rubber strip is gone too. The bike runs very good but by looking at the lines on the print out it could run better I think. The lines were very wavy through out the curve, both hp and tq. The guy running the dyno did the first pull in 6th gear for the first then went to 5th for the last two. He lugged it down to 39 mph before starting every time. It was a dynojet sae with a correction factor of 1.04


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Discussion Starter #8
Would it do any good to have it dyno tuned and have a custom map made for it? Thanks for all the help trying to understand this.


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Would it do any good to have it dyno tuned and have a custom map made for it? Thanks for all the help trying to understand this.


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Nope. Sounds like you would be better off adding auto tune
 

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For the only mods being a fiter, exhaust and a tune, I don't see the bike picking up a significant amount of power. Besides elevation, Air temperature will impact your numbers also, so if the dyno was done on a hot day, you may not be seeing what the engine will make under cooler conditions.

But the important question is: what is your A/F ratio. Do you have a chart from that dyno? If you just loaded a pre-configured map, it may not be right for your mods and elevation level. What MPG are you getting?
 

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For the only mods being a fiter, exhaust and a tune, I don't see the bike picking up a significant amount of power.
Here is an example of a Stage 1 mod.



Granted, it uses D&D inch and a half diameter pipe past the cats instead of Victory inch and a half diameter pipe, but the results should be reasonably close.

Note that the peak numbers are nearly identical. The power throughout the range is significantly improved however. I do most of my spirited riding with the tach between 3k and 4k rpm. There is a nice power gain in that range.

Stop sweating the spec sheet, like Duned says, if it's running good go enjoy it. No one is paying you for your spec results...
 

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Discussion Starter #12
I am not sure what the A/F ratio is. I did get a chard from the dyno and I will try to get a picture of it on here. Yes it was a pre-configured map that Dynojet sent me. I am getting anywhere between 48-52 mpg's on the hwy.
 

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I am not sure what the A/F ratio is. I did get a chard from the dyno and I will try to get a picture of it on here. Yes it was a pre-configured map that Dynojet sent me. I am getting anywhere between 48-52 mpg's on the hwy.
A/F = Air to Fuel ratio

There is a theoretical sweet spot around 14.7 parts air to fuel, but in reality, they are a little more fuel efficient when the ratio is higher than that (lean) and produce a little more power when the ratio is lower (rich).

If you are getting 52 mpg, then either your bike is set extremely lean or you don't ride it hard enough to ever miss whatever it is you seek from your dyno sheet.
 

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A/F = Air to Fuel ratio

There is a theoretical sweet spot around 14.7 parts air to fuel, but in reality, they are a little more fuel efficient when the ratio is higher than that (lean) and produce a little more power when the ratio is lower (rich).

If you are getting 52 mpg, then either your bike is set extremely lean or you don't ride it hard enough to ever miss whatever it is you seek from your dyno sheet.
14.7 works great in a water cooled engine, but is way lean on an air/oil cooled bike
 

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14.7 is theoretically perfect for the EPA... nothing else.
Best power will be somplace around 13.8:1 for most engines (notice where the dashed target line is on dyno charts). Victory engines like fuel and 13.2-ish is where the horsepower lives.
 

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Discussion Starter #18
The 48-52 mpg is on the highway running 73-77mph. I do ride it harder while riding around town. Thats one of the reasons I bought a Vic instead of a Harley like a buddy of mine did and has had several problems with it so far. Will the autotune adjust the A/F ratio to where it needs to be or would it be better to have a map for hp and one for mpg and switch between the two for the type of riding I am doing? Just curious, if I did decide to go with cams what could I expect mpg wise? I do want both looks and performance but I still want it to be reliable.
 

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I had the complete opposite experince. The bike was super abrupt on/off the throttle at low rpm, it backfired on decel at a certain rpm, and gas mileage was in the 30s. After the tune it runs perfectly, drivability is exponentially better, no pops, and it gets 46 mpg.

So what A/F do you shoot for when you tune it?
Generally my A/F ranges from 13.9 at lower rpm/throttle positions up to around 13.1 at higher rpm/throttle positions. I think a lot depends on the dyno guy you use. My son and I both got our bikes dyno'd on the same day and were both equally disappointed in the results. He rides a CBR1000RR with a Bazzaz fuel manager and ended up tossing out the map built by the dyno guy same as I did.
 

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The 48-52 mpg is on the highway running 73-77mph. I do ride it harder while riding around town. Thats one of the reasons I bought a Vic instead of a Harley like a buddy of mine did and has had several problems with it so far. Will the autotune adjust the A/F ratio to where it needs to be or would it be better to have a map for hp and one for mpg and switch between the two for the type of riding I am doing? Just curious, if I did decide to go with cams what could I expect mpg wise? I do want both looks and performance but I still want it to be reliable.
The autotune will adjust the A/F ratio to whatever you set it to be on the A/F map. In my case I've built a single map that gives me the responsiveness I want in town, but leans out at highway speeds for mileage. If you really wanted to get detailed about it the Autotune gives you the ability to develop a separate A/F map based on what gear you're in, so you could specifically tune it for sixth gear if you wanted for best highway performance/mileage.
 
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