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Discussion Starter #1
Hi everyone, I finally found the document showing my recent results for the Dyno run testing. When the test was done I had installed a Trask Air Intake, and V&H Grenades full exhaust.
upload_2019-3-22_11-22-36.jpeg
 

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Correct me if I’m wrong, but that 15.5 A/F is brutally dangerous, right ??
 

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Discussion Starter #5
You notice a difference
Honestly, I did immediately. To recap, I installed Trask air intake and a V&H Grenades full exhaust. I then used the DynoJet PowerVision CX to find and install a new tune for the bike. I found the most similar flash available for my specific set-up and reflashed the bike. Immediately I noticed quicker slightly sharper, more responsive controls and throttle response. However, I have been experiencing some issues with gear shifting, notably 5 to 6 slipping or missing. I wish I had waited to have the DYNO test done with my factory set-up so I could have more data in comparison. Additionally losing all that weight off the bike permits an increase in agility and quicker handling of the bike, in my opinion.
 

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Discussion Starter #7
Correct me if I’m wrong, but that 15.5 A/F is brutally dangerous, right ??
Please explain. I'm still in the novice category for engine and related systems performance. I'm currently trying to use the DynoJet PV CX to scan and log the bikes electronic systems. Again, I'm still learning and appreciate any additional information that helps provide better bike performance along with increased rider safety.
 

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Correct me if I’m wrong, but that 15.5 A/F is brutally dangerous, right ??
Look at the torque curve being all over the place in the lower revs. I think you’re right and there’s room for improvement.

I would assume the A/F graphs are before/after flashing?
 

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Look at the torque curve being all over the place in the lower revs. I think you’re right and there’s room for improvement.

I would assume the A/F graphs are before/after flashing?
Yeah, there is definitely something “glitchy” in there...

For some reason, the dyno machine was processing what the bike provided...

Typically, a good and safe A/F mixture is 11.6-11.9...

When you want to stretch the motor, you can probably go up to 12.5 AF, but you run the risk of detonation...

With 15 AF’s, I’d never voluntarily wide open throttle my bike until I had someone dyno tune it from scratch...

15 AF’s are dangerously high and if you’re bike detonates, that will be a costly lesson...
 

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Look at the torque curve being all over the place in the lower revs. I think you’re right and there’s room for improvement.

I would assume the A/F graphs are before/after flashing?
That's what I thought at first, but look at the graph. That's not RPM. That's speed. So those peaks and valleys are shifting gears. That's why I asked for the RPM graph.
 

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Speed equals rpm, that’s a linear relationship.

Ride twice as fast, the rpm are twice as high (assuming you stay in the same gear).
 

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No. That graph is not linear to RPM. It is speed only. Going from low to high gear. That's why it looks funky going through the gears. They didn't go 0-115mph in the same gear. That's why we need to see a RPM graph. Pretty strange shift points too. Didn't wind it out at all in the middle gears, was just getting to top gear as quick as possible. That's why peak HP and torque are so low in the shifting.
 

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Then the graph would look different. This sure looks like a single gear pull. Look at the hp curve.

I think they could or did not connect the spark pickup, and used the roller speed instead.

As a comparison, this is an all gear dyno graph

21CB5035-B7D9-4846-BC7B-89ECB945C878.jpeg
 

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I have been a DynoJet dyno owner/operator for 26+ years, I HAVE myself generated some funky dyno graphs in my early years and have seen other funky dyno graphs from others, this one is interesting to say the least.....

RACNRAY
 
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^^ which makes sense with such a lean A/F at low rpm’s.
Dammit !!!

You pointed something out that is very important to me: the PEAK af was 15.7, but after the bike settles in, it’s sitting at a mean 12.5 towards the middle and end of the pull...

Apologies, I read the graph wrong...

And now that I see it’s a multi gear pull, the glitchiness is irrelevant...

12.5 af is about as high as you wanna go...

Ask them to show you the knock graph...if you don’t show knock at those af’s, then I’d say that bike is running strong (also assuming it’s running 93 octane)...
 

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The dyno graph shows both torque and horsepower. The horsepower curve is absolutely normal, and the torque curve should match also, in other words the roughness at the beginning of the torque curve should also be seen in the horsepower curve, they should match identical. So the horsepower curve is your normal one gear roll on run, and the torque curve is a separate run showing very quick shifting through the gears before the Run becomes consistent. You can only show multiple gear runs in the mile per hour scale , not to engine RPM . The two air fuel ratio graphs, the top one is probably the air fuel mixture as delivered, the bottom one is after tuning. I'll come back to this thread and post a normal Dyno run from my Chieftain Dark Horse on my Dino last weekend.
 

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Discussion Starter #20
Hey everyone. Big thanks for all your input and information regarding the posted graph. Admittedly, you have left me in the dust with the shop talk. Personally, I would like to get another Dyno test completed, the provider I used seemed slightly confused and not 100% in his trade. Again any advice is extremely welcomed and appreciated. Is the bike running to rich or lean? Any suggestions?
 
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