Author Topic: Dyno Test HP Torque & Air Fuel Ratio of G5 (Read 5428 times)

singhg5 · **on:** May 10, 2012, 09:36:54 pm

Something I wanted to know for a while. Took my G5 to a local Yamaha motorcycle dealer. He has a Dynamometer Model 250i made by Dynojet. In an hour, including set up, it was all done. The results are as follows for 2 runs.

Max Horse Power = 18.79 and 18.39 at Rear Wheel between 4700 - 4900 RPM. The curve goes up with RPM until it reaches max.

Max Torque (lbf.ft) = 23.19 and 22.91 between 3500 - 3800 RPM. Torque starts high and stays high upto 4000 RPM and then gradually declines up to 5200 RPM to 18 ft lbs.

Air Fuel Ratio hovers around mostly 13 upto 5000 RPM, with a slight dip to 12.8 at one point.

The Owner's Manual has a HP of 27.2 (20.3 KW at 5250 RPM) and Torque of 30.5 ft lbs (41.3 Nm at 4000 RPM). These values may be at crank.

This test was done on Stock G5 with OEM restrictive silencer and standard air filter.

singhg5 · **Reply #1 on:** May 10, 2012, 09:37:43 pm

My G5 power results are similar to those of Bare's bike whose max HP was 18.75 and Torque was 24.2 ft lbs. Air Fuel Ratio was also similar for these two bikes.

Here is my G5 Air Fuel Ratio Chart

fzr400 · **Reply #2 on:** May 10, 2012, 10:16:33 pm

good job thats cool. all power figures are at the crank unless stated otherwise.

fzr400 · **Reply #3 on:** May 10, 2012, 10:23:38 pm

mine just has to be more then that as i passed a harley on a hilly twisty 55mph back road! no kidding

Ducati Scotty · **Reply #4 on:** May 11, 2012, 12:33:21 am

Why do they even measure hp at the crank? It's like looking at your paycheck before taxes, just makes you depressed when you see the final number

Scott

ace.cafe · **Reply #5 on:** May 11, 2012, 12:55:33 am

Those figures fall into the same ballpark as the others that I've seen.

Yours might be slightly lower, but each dyno varies some, so you can't rely on them to be exact in comparison to testing on another dyno. They are best used to take a baseline reading of your bike, and then compare to that after you make tuning changes.

Also, you might want to consider re-sizing your jpeg images to something smaller than the Milky Way Galaxy, so we can actually read them.

GlennF · **Reply #6 on:** May 11, 2012, 01:42:05 am

Quote from: ace.cafe on May 11, 2012, 12:55:33 am

Also, you might want to consider re-sizing your jpeg images to something smaller than the Milky Way Galaxy, so we can actually read them.

If you are using Firefox, right click the thumbnail and "open in new tab" helps when viewing massively oversized pictures.

singhg5 · **Reply #7 on:** May 11, 2012, 02:27:52 am

Quote from: ace.cafe on May 11, 2012, 12:55:33 am

Also, you might want to consider re-sizing your jpeg images to something smaller than the Milky Way Galaxy, so we can actually read them.

Bring cursor on the picture, then RIGHT CLICK the mouse - it will open a Menu,

Select OPEN LINK IN NEW TAB - LEFT CLICK that.

A New Tab opens and Complete graph will be visible in one screen, just like paper graph on a 8 x 11 " paper - Very easy to read, because it shows everything on one page.

In the NEW TAB picture, if you move the cursor, it will have a + symbol, if you Left click, the picture will enlarge. Most probably you will not need this Option.

It works even on Internet Explorer.

barenekd · **Reply #8 on:** May 11, 2012, 08:00:33 pm

Interesting comparison.
My 2011 G-5 Dyno test, EFI muffler and K&N filter.Our HP readings are almost identical
18.45 and 18.43, the torque as a little higher on mine, 24.42 and 24.23.
The mixtures appear to be essentially identical.
So, for those looking for a big HP gain with the EFI muffer, it doesn't appear to be there. However, it does sound a lot better!
My shutoff, though, is 5900.
Mine was done on a dynojet, too, but I don't recall the model.
As a real world comparison, Jack's and my bike are slow close in performance, both 2011 G5s, that there just really any difference. He has a Dunstall silencer and K&N filter.We were going up a long straight hill at about 6000 feet elevation. We had about a 51 MPH top speed. He as about 100 yards ahead of me and we were just glued at that gap, I ducked down and tucked in as well as I could and as just barely make ground on him, but I was catching him. We have the same 18T gearing, too.
With as mildly as these engines are tuned, you really can't hurt them, or help them much with these external mods.
Bare

singhg5 · **Reply #9 on:** May 11, 2012, 09:35:41 pm

Quote from: barenekd on May 11, 2012, 08:00:33 pm

Interesting comparison. My 2011 G-5 Dyno test, EFI muffler and K&N filter.Our HP readings are almost identical 18.45 and 18.43, the torque as a little higher on mine, 24.42 and 24.23. The mixtures appear to be essentially identical.

So, for those looking for a big HP gain with the EFI muffer, it doesn't appear to be there. However, it does sound a lot better! My shutoff, though, is 5900.

These external mods - EFI silencer and K&N filter - may provide only minimal gains (may be 5% ?). To detect very small changes in performance, the test has to be done on the same bike and at the same dyno machine, before and after mods.

My bike did not accelerate any more after 5250 rpm, which is below the Shut Off limit set at 5500 rpm by factory, because it ran out of horse power.

How did your bike manage to keep running past 5500 rpm (up to 5900 rpm) and did not shut off as it should at 5500. Do you have any ideas ? May be these numbers are not so precise and there is some variability in results.

Bottom line is that the figures are comparable and are in the same ball park, considering my bike is 2009 and yours 2011 - not much changes with RE !

barenekd · **Reply #10 on:** May 11, 2012, 11:08:32 pm

Have to guess that the electronics are a bit different between the bikes. I would think the tach on the dynos would be pretty accurate.
I can't think that your horsepower would be inadequate to push the tach past to the 5500 mark. You only have about at most 1/2 horsepower less than mine at 5250, and with the drop off 5250 that I have doesn't stop the tach from operating, Manufacturing tolerances is between the bikes is all I can come up with. And the way the power just drops off would indicate the engine quit.
But for me, the difference between 5250 and 5900 probably doesn't make any difference to me. I doubt that my engine ever gets above maybe 4500. Performance drops off so much after that, I'd rather short shift.
Bare

jartist · **Reply #11 on:** May 12, 2012, 06:05:48 am

I'll bet it has more to do with the different Dyno machines working differently. One machine might put a bit more of a load on the engine but use the same force times distance times time formula to get the same hp numbers.

BRADEY · **Reply #12 on:** May 12, 2012, 07:42:37 am

Assuming that short shifting at 4500 RPMs (as barenekd suggests) is the best way to keep in the power and torque range, my query is, how many RPMs does the stock C5 with 18T sprocket drop with each higher gear shift. And how does this compare if there was a 19T front sprocket.

Sorry but if this has already been discussed, any kind soul may point me to the appropriate link. Thanks.

barenekd · **Reply #13 on:** May 12, 2012, 05:54:44 pm

Here are a couple of speed vs RPM charts for the G5 17T and 18T. The ratios and speeds should be about the same with the C5 with the 18T and 19T sprockets. Give me the circumference of the rear tire and I can run them for the C5.
Bare

Ice · **Reply #14 on:** May 13, 2012, 12:44:05 am

Br. Bare,, Could you crunch the numbers for a 19 T sprocket for curiosities sake please.
Cheers.

Kevin Mahoney · **Reply #15 on:** May 13, 2012, 01:28:26 am

Dyno-Jet reading can only be compared to other Dyno-Jet reading. They do not correlate to other types of dynos, they are their own deal.

Nothing wrong with them, but they do stand along. They are good for comparison readings which is what most people use them for

Arizoni · **Reply #16 on:** May 13, 2012, 02:58:21 am

To help Br. Bare, the pitch diameter of a 5/8 pitch 19 tooth sprocket is 3.797 inches.

The pitch diameter of a 5/8 pitch 18 tooth sprocket is 3.599 inches.

Based on these sizes I think the 19 pitch sprocket would reduce the engine speed by a factor of .948 of the 18 tooth sprockets speed..

singhg5 · **Reply #17 on:** May 13, 2012, 06:02:09 am

Made a video of the whole test and uploaded on the youtube -

http://www.youtube.com/watch?v=_sJejcw92Fs&feature=plcp

barenekd · **Reply #18 on:** May 13, 2012, 04:31:18 pm

Quote

To help Br. Bare, the pitch diameter of a 5/8 pitch 19 tooth sprocket is 3.797 inches.

The pitch diameter of a 5/8 pitch 18 tooth sprocket is 3.599 inches.

Based on these sizes I think the 19 pitch sprocket would reduce the engine speed by a factor of .948 of the 18 tooth sprockets speed..

Thank you, Jim

But I need the diameter or circumference of the 18" tire to put into the Speed vs RPM formula to calculate the actual speeds.
Bare

Hobbydad · **Reply #19 on:** May 13, 2012, 10:10:20 pm

201cm sound right? I taped the center line of the tire tread, then took off the tape and measured it. I think that's correct.

barenekd · **Reply #20 on:** May 15, 2012, 11:53:59 pm

Quote

201cm sound right?

That sounds like it would be right.
Thanks, Br. Hobbydad.
Charts below
Bare

gremlin · **Reply #21 on:** May 16, 2012, 09:19:17 am

Quote from: Arizoni on May 13, 2012, 02:58:21 am

To help Br. Bare, the pitch diameter of a 5/8 pitch 19 tooth sprocket is 3.797 inches.

The pitch diameter of a 5/8 pitch 18 tooth sprocket is 3.599 inches.

Based on these sizes I think the 19 pitch sprocket would reduce the engine speed by a factor of .948 of the 18 tooth sprockets speed..

or maybe just multiply by 18/19th's ?

barenekd · **Reply #22 on:** May 16, 2012, 03:42:57 pm

19T chart attached in previous post
Bare