Tune up expectation

Last week I installed a tune up in my 05 that was to address several issues. Decel pop, speedo error, secondary throttle plates etc. The bike runs like a scalded cat if desired, the decel pop (used to start at 2200 RPM) is OK down to 1300 RPM where it pops loud and long as it did before (which means that it still needs richened up), the speedo is corrected.

SOOOO what the problem? I went for a 200 mile ride and found my fuel mileage had dropped from 36 MPG to 29.6 MPG. Now before any one goes nuts and tells me that I can't have my cake and eat it too...the question is, when the bike is riden at slow speeds, short shifted, no right wrist antics, in other words riden like a little old lady going to church on Sunday...what should the mileage have dropped too? (PS the entire route was run on secondary roads no faster than 55 MPH) Is this what I should have been expected? The additional perfomance is great but...maybe I should have explored another avenue? I frankly did not consider the mileage would drop that far provided the bike was riden the safe and sane method.

I should also mention that I broke a cardinal rule and made two changes at the same time that could have effected the mileage issue of the bike. The second change was the K&N under the tank update. Could this mod be restricting air flow?

Any thoughts? (Go ahead Flip and let me have it) SB.

SB- it doesn't take very many good twists on the throttle to cause the mpg to drop. I usually expect to get 30 to 35 mpg. What tune did you install? And what exhaust set up do you have?

By you installing a tune, do you mean you took it to the dealer and had them install the tune? Also, like Pig9r asked, what exhaust are you running?

The reason I ask is the last time I had mine in at the dealer, they installed the "corrected" fuel map (tune) according to the latest service bulletin. I am running TORs/ cat by-pass along with a PC-III. I am assuming the dealer installed Triumph's TORs/cat by-pass fuel map, which really messed me up since I was running the PC-III map as well. However, when I removed the PC-III, my bike was running exactly as you describe. To fix all of this (my dealer is 90 miles away), I started looking at other PC-III fuel maps. After looking at the European TOR/cat-bypass version, I decided to install it on my PC-III and give it a try. Would you believe my bike is running better than ever!..

Obviously, I could have it dyno tuned to get her running perfect, but it's running so good right now, I hate to mess with it.

Silver Bullet said:

I should also mention that I broke a cardinal rule and made two changes at the same time that could have effected the mileage issue of the bike. The second change was the K&N under the tank update. Could this mod be restricting air flow?

Any thoughts? (Go ahead Flip and let me have it) SB.

Click to expand...

Th K&N filter is less restrictive than stock. I get around 32 mph with the same tune. I've never seen 35 mph but I've never driven solid highway for a full tank.

Dougl tune up

Pigr: I don't remember the exact tune up number (20050TORSCATelimdecel was part of it) but I got it from Dougl. When I get home this PM I will look up the tune up number and post it. Dougl would know the number right off the top of his head since he runs the same one. I am also considering the corrected altitude difference between where Dougl is and where I am. It is considerable.

DougL: Thanks for the imput on the K&N air filter which can now be eliminated from consideration as a reason for the mileage drop.

Yes I am very aware that it doesn't take much of a twist in the wrist to drop mileage by quit a bit. My intent and riding stype on this trip was to check and see how much mileage I lost with this tune up to address the decel pop issue which is what was really driving me crazy.

TxRIIIRider: I have TOR pipes, CAt box eliminated and Under the tank K&N.

My purpose in throwing this out there was to canvas the Captains who have loaded Tune Ups with Tune Boy to determine where I am mileage wise compared to others considering the fact that I know the tune up still needs some refinements to get rid of the rest of the decel pop from 1300 RPM down. Maybe I will just have to live with it as opposed to dropping more fuel into the engine on decel. You see...I have this quirky idea that one can tune an engine for maximum performance and still get decent mileage when riden accordingly but just know that Pigr is right about the right wrist.

I have not had this bike back on the dyno as Dougl requested but intend too provided the winter weather stays away long enough to accomplish that task. The high today will be around 55 degrees which makes for a chilly trip to and from the Dyno locaton. It may in fact have to wait until spring. SB.

You said, "...like a scalded cat..." , "...like a little old lady...", but at the same time you speak of loud and long decel popping below 1300. I think this little old lady wears stilettos and leathers I wouldn't base mileage on a single tank fill or even two. I have occasionally seen 29 and 30, perhaps after a gentle ride over the mountain, while on average I get is 34.

The little bit of tweaking for the decel popping is way down low on the throttle positioning, like <%7. That won't screw with mileage. You must be doggin it :O

HeR3tic:

Great response...I find myself strangely excited by the stilleto's and leather....no one has ever described her quite that way...

I agree with the one trip mileage check statement but, this time of year one trip is all the dicipline I could muster in riding her "like a little old lady", come to think of it...that is the most discipline I have shown in years.... SB.

PS. The only way to stop the decel pop from 1300 RPM down is to pull the clutch lever and let it idle down fast.

Silver Bullet said:

HeR3tic:

Great response...I find myself strangely excited by the stilleto's and leather....no one has ever described her quite that way...

I agree with the one trip mileage check statement but, this time of year one trip is all the dicipline I could muster in riding her "like a little old lady", come to think of it...that is the most discipline I have shown in years.... SB.

PS. The only way to stop the decel pop from 1300 RPM down is to pull the clutch lever and let it idle down fast.

Click to expand...

IT has been suggested, though I've not heard of anyone going further, that an additional 3-5% added to that portion of the L1-3 tables that had already been adjusted by 10-15%, Pig9r posted one example table, might be appropriate.

I have bologna stockers and I too have a wee tiny bit of decel pop at perhaps 1300; but it doesn't bother me in the least. With TORs or other big mouth pipes I'm sure it's a bit louder; I can only imagine what it was like beforehand.

You've not posted the tune number/description yet though I have an idea and I have a thought about it. But I'll wait till you confirm which tune. In fact, I've tweaked this same tune in the area I feel needs it and I'll be loading it myself this evening.
Coincidentally these tweak exist in the sweet spot torque range and up to perhaps 3600 RPM at 60% throttle and above. That would be your little old lady range of excitement
Now the Fuel Tables of this same tune may be the actual culprit. I'm going to try it regardless but may revert back in a week or so.

The tune number is 20050DynoFinalMap_TOR_CatBypass_Decel. As I said, this came from Dougl and I very much appreciate his imput and respect his opinions. I looked back through the notes and Doug stated that he was at 4500-5000 feet of altitude where he lives whereas, I am at 2000 feet or less for this time of year.

Does the difference in altitude come into play on the lower end of the throttle position or manifold pressure range? And...do you think that fattening up the fuel down in the 1300 RPM decel range will have much effect on the decel pop with the wide mouth TOR pipes? I suspect that the tune up works 100% for Doug or someone at higher altitude but is not quite refined for a lower altitude?

You do make a valid point about the larger diameter pipes that I had not considered especially since the weather has gotten much cooler here in the last couple of weeks. When I first installed this program it seemed to be working better than it does since the ambient temp took a downward turn by over 10 degrees. Do you think the pipes are pulling cold air back into the exhaust system contributing to the decel pop?

Also, the 200 mile ride to get a mileage benchmark...I'll bet a paycheck the tach never went over the 3K mark more than a half dozen times and never by more than 200 revs...now thats little ol lady riding.

I'm interested in your thoughts...thanks SB.

The bike should adjust itself to changes in altitude. There is an ambient barometric pressure sensor that rides in the airbox that takes a reading when the ignition is switched on just prior to start up.