Dyno results..
01-25-2008, 01:01 PM
#1
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Dyno results..
This seems low.. but.. I know there's DynoJet vs. WinDyn (which they used). They said they corrected for altitude. It's a stock bike with a K&N, re-jetted for altitude (smaller jets).
Opinions? (Oh, and they spelled my name wrong.. CronAS.. nice.) ;(
Opinions? (Oh, and they spelled my name wrong.. CronAS.. nice.) ;(
01-25-2008, 02:03 PM
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Seems a little low, but I've seen it before too. Why smaller jets? I know about the altitude thing(I grew up in Aurora) but the bikes are kind of lean stock, then add in the K&N and you might be WAY lean.
01-25-2008, 08:11 PM
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Bike was running rich even -after- the jets. Honda service manual recommends 1 size down above 4000 ft. altitude. After I did so, bike was VERY MUCH more snappy and accurate. Still not getting enough air though, plugs were dark (but not overly so). I ride a lot in the mountains near Mt.Evans and what-not so I'm usually at altitudes around 10-12,000 feet. I tried that altitude with stock jets and couldn't even get the bike to start for quite some time, now it's a breeze.
Dyno was done at 6000ft. Supposedly altitude was adjusted-for. Dynojet says the Hp was 93.0, STP says 87.9 DynoJet dyno, altitude-corrected. I was told that resistance was set to "normal" (so just a bit) but was told a lot of people that dyno bikes set it to a negative rating, giving inflated results. By adjusting this, it gives the customer happy smiles, or so he says, but it's bogus.
I'm still getting around 46mpg.
Suggestions?
Dyno was done at 6000ft. Supposedly altitude was adjusted-for. Dynojet says the Hp was 93.0, STP says 87.9 DynoJet dyno, altitude-corrected. I was told that resistance was set to "normal" (so just a bit) but was told a lot of people that dyno bikes set it to a negative rating, giving inflated results. By adjusting this, it gives the customer happy smiles, or so he says, but it's bogus.
I'm still getting around 46mpg.
Suggestions?
01-26-2008, 06:01 AM
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The question is are you unhappy with the way the bike rides and feels? If not, then who cares what the dyno says. If you still have stock gearing try adding a couple teeth to the rear sprocket. That makes a big difference in the feel and response.
01-26-2008, 09:07 AM
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Supposedly they compensated for altitude, though.. that's where I'm concerned. If they didn't, then I'm better than good, losing only about 13%, if they DID compensate, then I am losing 13% for no good reason.
They gave me another chart that indicates SAEPwr vs. STPPwr vs. DJWhPw. I think it's a rating of two dynometers. I believe the first one is Hp of 84.5, the second is the corrected version that reads 87.9 and then the final one, 93 Hp is what DynoJet would read.
They gave me another chart that indicates SAEPwr vs. STPPwr vs. DJWhPw. I think it's a rating of two dynometers. I believe the first one is Hp of 84.5, the second is the corrected version that reads 87.9 and then the final one, 93 Hp is what DynoJet would read.
01-26-2008, 10:17 AM
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01-26-2008, 04:30 PM
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Drew,
I dunno about yours, but mine was rich stock at sea level. After the bafflectomy and shimming needles it was closer to optimum. Then I went to K&N and slip-on and was a new story from there.
I dunno about yours, but mine was rich stock at sea level. After the bafflectomy and shimming needles it was closer to optimum. Then I went to K&N and slip-on and was a new story from there.
01-26-2008, 06:04 PM
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01-27-2008, 09:20 AM
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Greg, all readings I have seen on the Factory Pro dyno are low, that is my point, dynos read differently and a base line run vs runs with mods is what matters not the reading itself. Are you making more power with the change you are testing is the only relavent question.
BTW the jets on the above run are Factory Pro.
Lotusland, there is a mathematical correction formula for altitude, barometric pressure and temperature. JIM
BTW the jets on the above run are Factory Pro.
Lotusland, there is a mathematical correction formula for altitude, barometric pressure and temperature. JIM
Last edited by Jim TT; 01-27-2008 at 09:26 AM.
01-27-2008, 01:07 PM
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Generally, Hp & torque should be about 3% loss per 1000 feet of altitude. At over 4000ft altitude, since the bikes are carburated, they should be rejetted (see "Zen and the Art of Motorcycle Maintenance") leaner (ie. smaller jets). At 6000 ft. (Denver) you automatically lose 18% off the bat. Altitude adjustment just adds the 18% back on for customer approval and grins but it's BS. It's just a, "This is what you'd get a sea-level" with perfect barometer readings number by multiplying (in this case) the 18% you lost on top of the actual number.
I've known a few non-jetted Colorado Shawks only getting 35 mpg or less, sometimes in the high 20s. I'm getting 41-46mpg and once over 50mpg on a long, slow boring prairie ride. My low-fuel light comes on at 146 miles or later. My speedo has be re-calibrated to GPS spot-on using a Garmin StreetPilot C340 and an installed Speedohealer (which I recommend).
I guess I'm about where I should be on Hp, so I'm pretty happy. Vibrations mysteriously "went away". They re-adjusted the carbs using the pressure guage as opposed to eyeballed 2 1/2 turns out BS and hmmmmm... what do you know? Still, they said it was already spot-on before they checked it. I doubt it.
I've known a few non-jetted Colorado Shawks only getting 35 mpg or less, sometimes in the high 20s. I'm getting 41-46mpg and once over 50mpg on a long, slow boring prairie ride. My low-fuel light comes on at 146 miles or later. My speedo has be re-calibrated to GPS spot-on using a Garmin StreetPilot C340 and an installed Speedohealer (which I recommend).
I guess I'm about where I should be on Hp, so I'm pretty happy. Vibrations mysteriously "went away". They re-adjusted the carbs using the pressure guage as opposed to eyeballed 2 1/2 turns out BS and hmmmmm... what do you know? Still, they said it was already spot-on before they checked it. I doubt it.
01-29-2008, 07:44 PM
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Your speedo healer is throwing off your odometer, which just happens to be right on the mark. The speedo is off about 7-8% optimistic from the factory. So this is going to throw off your MPG calculations as well. If I'm thinking correctly, this will actually give you better mileage than what you think you're getting.
01-29-2008, 08:10 PM
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Your speedo healer is throwing off your odometer, which just happens to be right on the mark. The speedo is off about 7-8% optimistic from the factory. So this is going to throw off your MPG calculations as well. If I'm thinking correctly, this will actually give you better mileage than what you think you're getting.
01-29-2008, 09:29 PM
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Yeah, but I didn't check your math. 
Point is, if stock the speedo reads high and the odo is spot on, no matter what you change the gearing to, if you use the healer/black box to calibrate the speed correctly then the odo will be "slow".
Point is, if stock the speedo reads high and the odo is spot on, no matter what you change the gearing to, if you use the healer/black box to calibrate the speed correctly then the odo will be "slow".
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