dyno challenge

[chad502ex]

Originally posted by Guy400
I don't know. They only had the quad for one afternoon so it didn't allow them a whole lot of time for tuning, etc. Maybe they didn't have any dyno tires on site the day they ran this quad.

Thanks Guy, I realize those obvious possibilities. I would think for pipe manufactures, big #'s sells- not small #'s. Don't forget big #'s are alot more accurate #'s with slicks (maximum traction). I goal for those type of tests are for "Repeatabilty". Could they repeat those measurements again using stock rubber or slicks?

Oh, one more thing; I second the enjoyment and the valuable feedback that this site offers us atv enthusiast.

Chad502EX.com

[Doibugu2]

I give props to these companies coming here and laying it all out on the line. exriders has become a force, I mean how many people have gotten either free or replacement parts by posting a thread on exriders?

For HMF to stand behind there results is pretty awesome. They didn't come out with some BS # like 10 hp, there # seems to be pretty reasonible gain.

Also, I think we should cut them some slack, they only had the quad for 1 day, heck had to borrow it at that, and they even said that.

Lets give this a rest till the stupid thing is released to everyone, please?

[tdsongster]

I greatly applaud HMF for offering to do dyno testing. Many of the aftermarket companies that sell products for Quads proclaim increase in HP, but I almost never see a dyno chart backing up their claims!

I am not sure why this is, if you are building an automobile, almost every aftermarket part out there has dyno results. The magazines that cover hot rods, and engine builds always show their results on a dyno as well.

I wish this would become common practice in the ATV industry.

Once again, HMF is going in the right direction, I will keep an eye out for them when making future ATV purchases!

[2004TRX450R]

I would also like to aplaud HMF for the offer. I'd show up but it is a bit of a drive from WA. However 6hp sounds a bit much just for sock tires. If the quad is set up right there should be no slipping anyway so there shouldn't be a traction problem. The only problem I have seen with dynoing dirtbikes with knobies is that it makes the graph all gittery. It doesn't really lose much power and 6hp on something with only 42 claimed at the crank is a HUGE difference. I could belive maybe 2 or 3hp. Also like I have said before the claimed numbers are from the crank not the wheels so you will have some loss through the drive train as well.

[VIC]

Why would any pipe company lie and give lower #'s they are trying to sell their pipes it wouldn't benifit them to give low numbers unless they are real.

[Guy400]

Maybe the Yamaha gremlin snuck in and smeared butter all over the dyno's rollers

[nhbanshee]

I actually like the idea of companies posting dyno results using knobby tires instead of slicks. Unless you plan on doing asphault dragging, you wont be running slicks, so you will be losing the HP that their dyno numbers are showing.

In other words, by them using knobby tires, you are getting a true HP figure that will reflect what YOUR machine will have on the MX track, trails, or sand pits!

Why buy a part that is showing HP numbers you wont have, because you wont be running the same set up that they did during the dyno??? It doesnt make sense to me.

[chad502ex]

unbelievable.

It would be a great day for me if the ppl here that believe those dyno 33.1hp dyno results line up next to my 502 with their pink slips to see if their slip-on pipe really performs.

yea, butter was obviously all over those rollers. You'd have to be crazy to think HONDA would mass produce a quad with ONLY 5 more hp than a stock 400ex, even if the 450 has stock sneakers on. 33.1hp with stock tires for a 450r, not hardly!

nevermind, one more month, you'll see!

chad502ex.com

[Guy400]

Do I believe the 450R puts out more HP to the wheels than 33.1--yes.

Do I believe HMF intentionally raised/lowered/misinformed/skewed the results--no.

I fully anticipate that other dyno pulls will reflect higher numbers, even future pulls done by HMF. I wasn't there so I can't say what the temperature, humidity, state of tune, etc. was for that particular pull. Truthfully, I'm not all that concerned with it either. I'm more interested in what percentage gains HMF made on their own dyno on that particular day. Making a xx% gain in horsepower and torque speaks more to me than a peak number does anyway.

[lukester720]

Originally posted by nhbanshee
I actually like the idea of companies posting dyno results using knobby tires instead of slicks. Unless you plan on doing asphault dragging, you wont be running slicks, so you will be losing the HP that their dyno numbers are showing.

In other words, by them using knobby tires, you are getting a true HP figure that will reflect what YOUR machine will have on the MX track, trails, or sand pits!

Why buy a part that is showing HP numbers you wont have, because you wont be running the same set up that they did during the dyno??? It doesnt make sense to me.

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You may be right nhbanshee but I use different tires for different surfaces and conditions to get maxium traction. I would probably use slicks for maximium traction on the dyno. I use sand tires in the sand. Holeshots or claws on the track
I don't think knobbies would give maximium traction on a dyno but I don't know a lot about them so I could be wrong.