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Discussion Starter · #1 ·
Ive had a few wanting to see my tuned A/F curve so I got it and here it is....its conservative 8):
 

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Do you remember what your mods were then and your settings on the dobeck?
 

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VelociRaptor said:
My mods that I dynoed with havent changed and are in my sig. The settings are 5,5,2,9
Very nice man. 8)

Thanks for sharing.
 

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Discussion Starter · #7 ·
Mine are REAL low, even Dobeck sayed that it was on the low side. They were REAL helpful over the phone when I was at the dyno, the tech guy walked me through all of it- I even made a couple of pulls with him on the line and asked what it did then and were to go from there. Kudos to them for sure :thumbsup:
 

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sikraptor700 said:
Nice, what now dobeck haters, looks good
Doebecks suck.












J/K Had to do it to you Sik because I know it made your eyes bug out :rofl:
 

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MaxxRPM said:
sikraptor700 said:
Nice, what now dobeck haters, looks good
Yeah!..........and they said the Dobeck didn't have enough range for internal mods............Those settings are fairly low.
HAHA...they dont! Ask any engine builder. They reach there limit pretty quick. What did you think, we were all lying. I dont work for dynojet....nor do I own stock..haha...just passing on info.

The truth of the matter is, the doebeck style units are not as smart...dont have the capability, and are harder to tune...which usually equates to longer dyno tunes.

If you dont dyno tune, I will bet money every single time on the PCIII having a better tune!

This is like comparing a "procom" cdi unit to a vortec or dyna. Sure, the procom will work and do the job, but the vortec and/or dyna are a way better unit with better tuning features.
 

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I am not "dissing" on anyones decision to go with the Doebeck TFI.....just putting out more info.

Obviously VelociRaptor got his to work pretty well......I think he could do even better with a PCIII though and spend less time tuning.
 

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Discussion Starter · #11 ·
No problem boom, I did spend some time on the dyno and the phone. It worked out real well and I am satisfied with everything, especially the customer service :thumbsup:. I will say that from cars to quads, to get it right you should dyno tune it :grin_nod:
 

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I have now used Dobeck, Noss Boss and PCIII on 700R's that was one my dyno.

Here is the part no one ever tells you about the real difference between these units.

The Dobeck and Noss Boss works, but they have SERIOUS drawbacks. As mentioned, one of the biggest drawbacks, is the time it takes to have it set up correctly. I found these units to be very finicky and less than a 1mm turn on the accelerator pump can mean the gain or loss of nearly 3HP. The other major drawback with these units are their design and the way they fire the fuel injector.

These units connect in parallel with the injector and the stock EFI unit. Both the Dobeck and the stock EFI fire the injector simultaneously. This is fine for most cases under acceleration. When you need more fuel, the Dobeck fires the injector for a longer period, allowing more fuel to get into the motor, BUT, when the stock EFI is already adding to much fuel, the Dobeck or other parallel connection devices cannot make the injector signal less. You cannot make the fuel delivery leaner with a Dobeck or Noss Boss if the stock EFI is adding to much fuel

If you look at the dyno graph VelociRaptor posted, you can see the problem immediately. Just below 4000 RPM and again at 5300 RPM onwards you see a rich mixture. With a bit more time on the dyno, it might be possible to address the mixture in some areas, but they might not be able to fix it below 4000 RPM. Below 4000 RPM the mixture plays a major role in power output, and it is critical to get it perfect. This raptor can make much better low down torque if they sort that very rich condition out.

Also, keep in mind that this dyno graph has smoothed out the A/F ratio and it is quite small in size. If you zoom into the A/F mixture graph, you will be shocked to see how badly the results actually are.

The PCIII connects to the fuel injector in series with the stock EFI. This allows the PCIII to increase and decrease fuel delivery. It does not compete with the stock EFI signal at the injector. The PCIII has full control.

The Dobeck has 4 settings. Idle, 2 pots for mixture and one pot for accelerator pump. It will not allow you to target specific RPM's and fix just the problem area, You make compromises with these units and are forced to use averages to fix problems. When using average setting, you can fix the problem, but in doing so, create problems where there where none to start with.

The PCIII on the other hand can be set up for each 250 RPM, plus it has throttle position sensing, where the Dobeck and Noss Boss units don't.

Now to the biggest thing, most people forget when they look at the dyno graph. The posted graph seems fine, but this is only one very small part of the whole story.

That graph only shows that the ratio is ok for acceleration with full throttle. 95% of the time, most of you don't ride at full throttle, plus you don't accelerate all the time, sometimes you cruse around and do technical riding. The Dobeck units do not have the capability to address fuel delivery for other throttle positions, besides full throttle. It cannot sense throttle position, so it supplies fuel as per the full throttle, acceleration settings only. In most cases this is an serious overkill and causes very rich conditions, messing up your power delivery below full throttle.

The PCIII can sense the throttle position, and delivers fuel very differently depending on throttle position and RPM range. For example, when you cruse around, the fuel delivery is usually around the 14 to 15:1 ratio, but when you accelerate, it goes down to 13:1. You have a cruse mixture for using less fuel and cleaner burn in the combustion chamber. You have a different mixture for acceleration, where you don't care about fuel usage and carbon build-up in the engine.

Also note that running to rich also has it's own set of problems. To rich not only causes heavy carbon build-up, it also causes the fuel to settle on the sleeve, which dilutes the oil which lubricates the rings. If you don’t; lubricate the rings and the sides of the piston correctly, don’t expect it to last. This excess fuel also works its way past the rings and dilutes the oil in your crank case. So, it not only messes up the piston and rings, but all the other parts that need oil to lubricate it. With the Dobeck, I guarantee you that the combustion chamber and exhaust ports will carbon up 10 times faster than with a PCIII, and cause you to open that motor sooner than required and spend money on keeping it running. That little bit you save from buying a Dobeck, compared to a PCIII, will cost you big time in the future.

The Dobeck units work, don't get me wrong, but they are like a patch on a small peace of the problem. So, if you are a guy that uses the bike on the track and you just use acceleration, yes, the Dobeck units are fine, but if you find yourself using the bike for anything else, then the PCIII is the right option.

Next time you have a Dobeck on the Dyno, test the fuel delivery under load at throttle positions other than full throttle and see what it does.

You will see the other side, no one tells you about.

Guys, I am not here to slap down the Dobeck and Noss Boss units, but they don’t address the total fuel delivery problems on the 700R.
 

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Freez, you said it all! I would never recommend a Dobeck over a PCIII. The PCIII is superior in every way! Set-up, tuning, fuel delivery correction, ease of changing maps, and on and on. Thanks for the great write-up laying out some real differences! Dobeck owners, don't take that wrong, I'm not saying they "suck". I just think the PCIII is more than worth the small price premium.
 

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Great write up Freez. :thumbsup:
 

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Discussion Starter · #16 ·
Thanx for the post, I spent 3 hours on the dyno give or take a few minutes. I tuned it under half throttle as well. I have a clip of me riding at low RPM in the media section and its pretty good on the tune. It does change a little under different throttle positions but I got the "medium" of all like you said has to take place.....its still way better than a carb setup :grin_nod:
 
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