Got the bike dyno tuned

He's expensive and I didn't like his work. He tuned my Bonnie. I think he just put in a tune from the tuneboy site. I took by bike over to eximport and used there dyno and added 5 RWHP by getting the A/F right.
I reccommend a good A/F when tuning, and then fine tune up top for max power. To really get the most out of your bike, it takes a lot of time on a dyno. There is a lot of variables to play with. I don't want my bike running lean and those numbers listed above sound scary lean.
Anybody else out here that has tuned on a dyno want to comment. 19 or 26 to 1 A/F just sounds way too lean. I would be worried about burning it up at that setting. I would opt for a 13/1 and go from there. Maybe a little leaner at cruise (no more than 14.0) if you're worried about gas.
I'm with you about giving the bike what it likes, such as timing and fuel. My Bonnie wanted more fuel at WOT, and less timing for max HP.
Later
 
The guy that done my tune said they set my A/F to 13.5 at my cruzin speed of 70. With this done, my fuel economy has gone from 23 mpg to 28 mpg. I agree that anything higher than a 14 to 1 would be way too lean for long highway runs like I do. Not worth the chance of damaging a cylinder for the few pennies of fuel that you might be saving.

Big T
 
Under 10% throttle? Do you mean at idle? I richened my low a little to get rid of the decel popping on my Bonnie with it's engine mods. It reved fast and had a little too much popping due to going lean only on hard decel.
I'm new here. Just got my new Roadster home last week. However, I really hate to see someone give advice about running that lean and it being ok. Please don't take this wrong, but that A/F will ruin an engine.
Even with a good A/F on the dyno, if it's not an eddy current dyno with braking, you need to watch the monitor and look for lean spots(there red in color for a reason) on the screen. Then go back and work in that trottle position to get rid of the red. On a regular dyno jet dyno, you can tune for max power but you're really looking at WOT. I generally work in the 70% up TPos looking for RWHP.
Later
 
Go pull up a few of the many SAE papers on lean burn and lean cruise. The amount of information on the subject is staggering. Unfortunately many in the motorcycle world are in the dark on the subject. SAE Papers - By Technology - Join SAE for a discount.

The stock bike is tuned to run 14.57:1 (roughly stoich on pump gas - each brand and country is a bit different) at low load, using the stock narrow-band Lambda output. Also, see the datasheets for NTK UEGO units and Bosch Lambda sensors - Bosch Motorsport - Lambda

At low load (cruise) I have safely run as lean as 19:1 with stock ignitions, and 26:1 with high output CDI systems and good fuel preparation. These are actual mixture ratios taken from a multi-gas analyzer and converted using the Brettschneider equasion. http://www.allbrit.de/downloads/Allgemein/Brettschneider_Lambda.pdf

At low loads, the cylinder filling is low, and there is a good amount of EGR occuring - this can be enhanced. MANY automotive manufacturers run lean cruise. Many do not tend to go much leaner than Lambda 1 (other than Honda), because NOx increases, and it takes a good 4.9 Lambda sensor or UEGO to read leaner mixture correctly. At leaner mixtures, the free O2 content of the exhaust gases increases and most Lambda sensors read incorrectly - just as with oxygenated fuels and with misfires. FWIW, misfires occur regularly in all engines, it is the frequency of their occurance that matters.

The problem is lean misfire and stratified charge in the chamber - good fuel preparation and ignition can help, as can improved squish.

You will need added acceleration compensation to prevent hessitations and misfires when the throttle is suddenly opened from lean cruise.

It is not hard to have good fuel consumption at cruise, and best output everywhere else. It does make things easier if you have a dyno with low roller mass, and and an EGA, but it is far from mandatory. I used Dynojet inertia dynos to do this for many years prior to what I now own - you can even do it using a PCIII and the "Accelerator Pump Enable" software feature.
 
I assume guys like me that run TOR pipes with TOR tunes, while perhaps not getting the "most" power out of our bikes, are well within safe A/F ratios?

I have BC Hog Slayers on my T-Bird with the TOR tune and the TOR pipe and TOR tune on my Tiger. Both bikes have the stock air cleaner.
 
When I first got my bike dyno tuned, I had the guy do a base run to see where I was at. There were areas where I was 15 and 16 to 1. And that was with a canned Tuneboy tune.

These are the numbers I got with Maddogs and triple K&Ns.







This is where I ended up at with Nev's cams, Jardines and triple Uni filters. I lost some top end but pick up quite a bit in the mid range. The bike felt much stronger in between 2 to 4K RPMs.
 
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With one of the displays on my Scangauge set to TPS I routinely see throttle positions of 7-8 percent cruising at 70-75. As Wayne has so eloquently stated, running a bit lean at that level will do no harm whatsoever.

Triumph, who issues the warranty, sets the stock tune to run lean at cruise. Better fuel mileage, reduced emissions, and no risk.
 
..I just read this whole thread and don't have a clue what any of it means..so my intent is to go down to Birmingham and see Mr. Wayne Power Tripp and get a proper dyno for me beast..I'm currently running triple K&Ns, a canned tuneboy tune that Sam provided, and Predator pipes..gotta replace the TPS first..
 
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