Dyno- FMF Megabomb, Powercore 4, Tuner

Putting the WR on my dyno today. Prelimary run shows 27hp and 27 torque. Will report back with pictures and more information

27 torque...that's almost double the stock number (to good to be true??)!! Keep us posted

In the excitement I totally forgot to save snapshots or take pictures... I did about ten runs though with different fuel settings, I'll get those for you guys on Monday when I'm back in the shop. No matter the changes I made, hp and torque were always 25.5-27 each. Yes, torque is 27 ft/lb. The main goal was to get the air/fuel ratio as close to stoichiometric (14.7 parts air/fuel). To start with, I have the following mods:

Fmf Powercore 4 Exhaust
Fmf Megabomb header
Fmf PCM
Flapper removed
AIS removed
13/48 gearing

Having never touched the programmer since installing over a year ago, the first A/F reading was 12.5. Quite rich. Added more and more gas until I got a consistent 14.2-14.5 acrossed all RPM ranges (beautiful straight line, can't believe I forgot snapshots). It really had no effect on HP or torque readings, but it was really noticeable in the test ride. FELT way more powerful. No hesitation, no bog, pulled very strong through all gears. Even lofts pretty easy in second now with just gas. Sounds different too.

Also changed coolant, rebuilt front and rear suspension (thicker oil too in both), all new bearings all the way around (steering, swingarm, wheel), new spark plug, replaced cooling fan (crushed), and fuel pump (defective), and dielectric greased all electrical connections. All said and done, I'm quite pleased with the results. Now we'll see how much gas mileage suffers.

Will post pictures and tuner settings early next week.

That's awesome! How did you determine that the A/F ratio should be in the 14.7 range? Mine is set at 13.2 at the recommendation of Dave at Fast Bike Industries. I don't know how he came up with that number.

BuilderBob wrote:

That's awesome! How did you determine that the A/F ratio should be in the 14.7 range? Mine is set at 13.2 at the recommendation of Dave at Fast Bike Industries. I don't know how he came up with that number.

It's called Chemistry

Solving the stoichiometric equation gives the theoretical correct ratio of two substances in order to maximize the products of the reaction, with no reactants left. Basically, what ratio you need so that no reactants are left. This will produce the highest yield of products. Now speaking in engine terms, this should theoretically give you the best bang for the buck. all the fuel is combusted perfectly, with no excess of air or no excess of fuel. It's really relatively basic chemistry. You can read more about it here

http://en.wikipedia.org/wiki/Stoichiometry

and

http://en.wikipedia.org/wiki/Air%E2%80%93fuel_ratio

So really a ratio of 13.2 to 1 is a bit rich. But whether hitting a ratio of 14.7 to 1 really gives the most power is questionable . at least you aren't "wasting" anything, and it's running at the theoretically most environment friendly spot.

Awesome info! Thanks for the details. Did you know the person with the dyno? Have a cost estimate for the runs? I was thinking about getting my similar setup dialed in by a shop with a dyno, I could take this info to them!

mvonhatten wrote:

Awesome info! Thanks for the details. Did you know the person with the dyno? Have a cost estimate for the runs? I was thinking about getting my similar setup dialed in by a shop with a dyno, I could take this info to them!

There are benefits to being a mechanic. When you do the runs and work yourself, free is great.

I went for 14.7 because, as bigg mentioned, it's the most efficient. It's generally acknowledged that the leaner the mixture is, the more power you create. Drag cars pushing thousands of horsepower run incredibly lean, they are pre-detonating the entire run. Those motors are built for one day. Two runs, maybe three, they put a brand new motor in. Obviously that's not what I'm looking for with the WR, but I did go up to about 16 and see what it did. It did make a little more power, but rideability was decreased enough that I put her back down closer to stoichiometric.

kjharn wrote:

14.7 because, as bigg mentioned, it's the most efficient. It's generally acknowledged that the leaner the mixture is, the more power you create. Drag cars pushing thousands of horsepower run incredibly lean, they are pre-detonating the entire run.

Uhh i think you may be mistaken.
For a start top fuelers don't pre-detonate, they run such high compression pressures they actually diesel. They also run nitro methanol, not gasoline (alkanes like octane).
Most engines make the most power when run slightly on the rich side of mixtures, as this increases the cooling effect of evaporation on intake charge, it also allows for inefficiencies of the burn - ensuring that all oxygen is burnt up even if all fuel isn't. Any engine built for max power never runs a stoich. mix - any fluctuations towards the lean side of things can cause misfiring, pinging, pre-detonation and an increase in heat transferred to the engine metals. This is usually seen in a motorbike engine that runs lean and soon burns the piston out turning it to a molten slag ball.
builderbob is right that a rough aim for power tuning purposes is 13.2:1
The only time a stoich mixture is ideal is when you're aiming for max efficiency - not power. They are two different things and whilst sometimes they can both be achieved at the same time most tweaks only increase one of the two.
Because an engine does not work the same all the time most tuners will instead aim to keep the engine in a richer setting during high load, and only lean out to stoich. under cruise settings to avoid destroying an engine due to an unforeseen lean out condition.

xy500 wrote:

kjharn wrote:

14.7 because, as bigg mentioned, it's the most efficient. It's generally acknowledged that the leaner the mixture is, the more power you create. Drag cars pushing thousands of horsepower run incredibly lean, they are pre-detonating the entire run.

Uhh i think you may be mistaken.
Most engines make the most power when run slightly on the rich side of mixtures, as this increases the cooling effect of evaporation on intake charge, it also allows for inefficiencies of the burn - ensuring that all oxygen is burnt up even if all fuel isn't. Any engine built for max power never runs a stoich. mix - any fluctuations towards the lean side of things can cause misfiring, pinging, pre-detonation and an increase in heat transferred to the engine metals. This is usually seen in a motorbike engine that runs lean and soon burns the piston out turning it to a molten slag ball.
builderbob is right that a rough aim for power tuning purposes is 13.2:1
The only time a stoich mixture is ideal is when you're aiming for max efficiency - not power. They are two different things and whilst sometimes they can both be achieved at the same time most tweaks only increase one of the two.
Because an engine does not work the same all the time most tuners will instead aim to keep the engine in a richer setting during high load, and only lean out to stoich. under cruise settings to avoid destroying an engine due to an unforeseen lean out condition.

As I said in my original post, I was running at 12.5 originally. Rode like crap compared to now. Feels stronger and rides better, that's all that matters. You're right, generally you do tune slightly on the rich side, but in this particular instance it feels way better at a leaner setting. Each bike's different.

As far as my statement regarding lean, it's true. Lean the shit out of a motor, it'll run like crap, but it'll make more power. Especially in racing engines.

kjharn wrote:

As far as my statement regarding lean, it's true. Lean the shit out of a motor, it'll run like crap, but it'll make more power. Especially in racing engines.

It's not that I'm questioning your personal experiences, but the experience of many others in over 100 years of engine tuning says otherwise. A richer mix makes for a smoother engine and more power...
Lean it out too far and it'll cough, fart, backfire through your intake and set fire to your air filter. Ask me how i found out about that one.

xy500 wrote:

kjharn wrote:

As far as my statement regarding lean, it's true. Lean the shit out of a motor, it'll run like crap, but it'll make more power. Especially in racing engines.

It's not that I'm questioning your personal experiences, but the experience of many others in over 100 years of engine tuning says otherwise. A richer mix makes for a smoother engine and more power...

Question away, you won't offend me. If I'm wrong, I'm wrong. It's not my personal, experiences, really. Moreso that of my professor from mechanic school. He spent 30 years building racers after being a national level motocross and trials rider. Now he builds custom frames and flat trackers. I'm not telling anyone to go run numbers like 18 on your WR, he always told us to shoot for around 13 for rideability and smooth power. For his track bike motors, he'd lean it out until it knocked, then richen it slightly. It definitely worked for him. Still does.

I asked Eddie Sisneros, jetting guru and moderator on that other forum, what he advised for setting up my WRR with PCV and AT:

Eddie Sisneros 11/12/09

You will find that above 14.0 the bike will run bad; I would not go leaner than 14.0.
12.8 is also rich for max power production; you will want 13.0-13.2.

Spark plug readings and rideability tests say otherwise. No pinging, Bike runs nice and cool. Nice torque and hp curves. I've had this bike since 2010 when it had 0 miles on it, now it just just over 14,000. I assure you, this is the best the bike has ever ran, and I made 11 dyno runs and test rode every other run. This is the best set-up for my bike.

What programmer are you using?
What settings?

I won't argue with your settings. I think it's great that you are squeezing so much out of the motor, considering that you've not cracked it open to do internal upgrades. On the other hand, if it's running too lean, it could be a short lived experience.

Again, I'm no expert. Keep us posted on your experience with it, and post up those dyno sheets when you can.

ramz wrote:

What programmer are you using?
What settings?

Yeah, What he said

If you're running clost to 14.7 on wot and that's making power then your A/F meter is giving out incorrect readings.

For a naturally aspirated motor you need to be in the region of 13 to 13.7 (more specifically 13.2-13.5)

stumo wrote:

If you're running clost to 14.7 on wot and that's making power then your A/F meter is giving out incorrect readings.

For a naturally aspirated motor you need to be in the region of 13 to 13.7 (more specifically 13.2-13.5)

It's a full DynoJet computer and dynomometer system. Verified with 2 stock SV650's immediately following my bike; both at 14.7. Then a modded R1 with chip. Ran stock settings with it, A/F 14.4. Power increased and was greatest at 13.3 So it seems the meter is fine. I don't know why this is the case with this bike, but it seems happy at the purported 14. I did dial it down to 13.6 and ran it for 200 miles, before going back to 14.0. Definitely feels better at 14.0.

Still failing at getting the dyno pictures posted, but I'm trying to remember. 80 work weeks aren't boding well with me, on top of school. I'll try and get programmer settings for you guys tomorrow. Been riding the Shadow lately for my longer commute.

If you are measuring A/F reading with a sensor clipped onto the tail pipe it will show a leaner mixture than what you're actually running.

Best method to get an accurate reading to to have it mounted in the exhaust stream roughly 18-24" from the cylinder head (pretty much where the stock euro sensor is).

Arkmage wrote:

If you are measuring A/F reading with a sensor clipped onto the tail pipe it will show a leaner mixture than what you're actually running.

Best method to get an accurate reading to to have it mounted in the exhaust stream roughly 18-24" from the cylinder head (pretty much where the stock euro sensor is).

Nope, installed a valve into my FMF Megabomb header.

a valve?

Yes, we install valves into headpipes to get optimal A/F readings, when customers allow. Namely on bikes with catalytic converters, but I like to do it on all my bikes also. Screw off shradar type, so you can put the sensor closer to the cylinder for accurate readings. Suprisingly enough most people aren't willing to let us drill a hole and tap a valve into their head pipe, but not a problem for me.

Wait, people are believing 27 ft/lbs of torque?? What am I missing? Even the dynos I have seen for the BB kits never have more than 20 ft/lbs but they make that amount sooner in the powerband. Torque matching horsepower output on a 250cc revvy engine? I must be missing something.

I've not seen an actual dyno chart posted. I believe very little when it's just text on the interwebz....

I'll believe these numbers: click me <---