MPG Down

[Two4One]

I made a bunch of changes to my 2003 Bird in the past month. Powder coated the wheels, swingarm, fork lowers installed HyperPro front and rear spring(s), replaced all associated bearings, painted stuff...ad nauseum! I noticed my MPG was dipping slightly towards the end of last season. I was expecting my issues to be suspension related because my original equipment was TIRED!!! Figured I was putting all the pressure on the tires due to my increasing tire wear issues. Anyway, I finished my first tank of gas post upgrades and I used to get the blinking light at 185 miles but again last night the warning light came on at 156 miles.

Another element to all this is one of my riding buddies has noticed that he can "smell" my bike when I get on it hard. I also replaced the stock cans with another set of stock cans so who knows if it was just the packing wearing out or what? Just throwing that out there for more info. I haven't had the chance to ride with him again since the change to see if he's experiencing the same thing.

All that being said, I have in fact progressed from "B" to "A" in the NESBA group. I am wondering if I'm simply experiencing the associated characteristics, ie. more throttle=more gas=quicker tire wear? If anyone has experienced a reduction in MPG, please let me know. As long as I can eliminate a mechanical issue, I'm fine with the MPG reduction.

The bike has 32,1xx miles on it. Never changed fuel filter or had the top end apart for any reason. I do clean the air filter, change plugs, change oil, etc. per the recommendations.

Here's a photo of the bike with the recent changes. Thanks for any help you can provide!

[Dion]

Whoa! you're riding "A" on the Bird??

[Two4One]

Whoa! you're riding "A" on the Bird??

Well actually no but I will be. Sorry for the confusion. I have a 1997 F3 track bike which I am selling. I will be drastically reducing my track day schedule so any future days will be done on the Bird. She's more than capable

[jcrich]

I think all that powdercoat is weighing you down. Sorry, I got nothing.

Seeing a XX out in the "A" group would be a sight to behold.

[Keith]

I also replaced the stock cans with another set of stock cans so who knows if it was just the packing wearing out or what? J

I can't help with your loss in MPG, but from a cut away picture of the stock can posted

here some time back, it appears there is no packing inside. Maybe someone here still

has that picture somewhere that they can post up. I Googled it, but came up empty.

[The Krypt Keeper]

what yr is your XX

if its Carbed you might want to start there. Give them a good go over and maybe even get them sync'ed in.

Check your brakes pads to make sure there is no extreme dragging issues, some dragging is normal but not alot.

Check your chain to be properly adjusted, and also no binding links

Said you never been into the top end. Might be a good reason to peek in on your valve clearence.

one thing might not give to much fuel change but several things together can seriously have effects.

[Para045]

I also replaced the stock cans with another set of stock cans so who knows if it was just the packing wearing out or what? J

I can't help with your loss in MPG, but from a cut away picture of the stock can posted

here some time back, it appears there is no packing inside. Maybe someone here still

has that picture somewhere that they can post up. I Googled it, but came up empty.

Try here CBR1100XX Can Autopsy :icon_think:

[Dion]

Whoa! you're riding "A" on the Bird??

Well actually no but I will be. Sorry for the confusion. I have a 1997 F3 track bike which I am selling. I will be drastically reducing my track day schedule so any future days will be done on the Bird. She's more than capable

Really........ what are you looking for for the F3?

[Two4One]

what yr is your XX

if its Carbed you might want to start there. Give them a good go over and maybe even get them sync'ed in.

Check your brakes pads to make sure there is no extreme dragging issues, some dragging is normal but not alot.

Check your chain to be properly adjusted, and also no binding links

Said you never been into the top end. Might be a good reason to peek in on your valve clearence.

one thing might not give to much fuel change but several things together can seriously have effects.

Thanks for the feedback. It's a 2003, sorry I forgot to add that. There is no abnormal drag from the front or rear. Matter of fact in order to completely eliminate the rear as a possibility, I removed the entire wheel and re-checked my bearing installation, etc. I also thoroughly cleaned and lubed the chain just to be sure. The chain did loosen up some, but not nearly enough to reduce my MPG so drastically. In my opinion anyway. The chain has less than 8,000 miles on it so it is relatively fresh to begin with.

I'm leaving for Deal's Gap this Sunday. I'll be able to get a better feel for the bike post upgrades. Maybe something will become apparent.

Dion, here is the info on my F3: http://www.nesba.com/TrackTalk/bb/Forum4/HTML/006480.html - She's a real solid bike, No BS!

I think all that powdercoat is weighing you down. Sorry, I got nothing.

Seeing a XX out in the "A" group would be a sight to behold.

Tell me about it! I just want to have an "A" sticker on the Bird. I would be out braked, out accelerated and out handled but not "out funned", haha!

[The Krypt Keeper]

deals gap.. have fun, shouldn't be to many squids there yet.

If your bike has been sitting since you last did any service pull your filter and make sure a mouse hasn't taken up home in there. I had that happen on my 750 a few yrs back. Had a notepad with a checkoff list for some winter service. Couldn't find it a few weeks later. Went to do my airfilter and found it.

Also living in the sticks and with corn fields across the road from me. My stock pipes sat around for a couple yrs. Went to move them and had to kick a mouse out of them and shake them fuggers for hours to remove the corn..

I now keep plenty of poison pellets around my basement to keep them fury critters away from my bikes.

[SGT Ski]

I'll tell my dad to set up a mouse trap by the pipe and airbox on that virago when he gets home

you can never be to safe

[Iceman_40]

How much has your MPG changed?

What about your driving style?   I'm guessing since you were racing and improving that your probably riding a bit harder that alone will effect the MPG.   I know I'm lucky to get 200Km on the tank if I'm dicking around...

[Keith]

Try here CBR1100XX Can Autopsy :icon_think:

OK, thanks for the link. I guess, from looking at this picture, there is at least a little

packing, unless that's just insulation:

[Para045]

Try here CBR1100XX Can Autopsy :icon_think:

OK, thanks for the link. I guess, from looking at this picture, there is at least a little

packing, unless that's just insulation:

Yeah I think mainly for insulation purposes :icon_think: from what I have read the "muffling" effectis due to the gases being shuffled back and forth through different passages rather than through thick packing :icon_think:

[Two4One]

Well I'm pretty sure I don't have a mouse issue, thanks for the heads up though. Good stuff!

How much has my mileage gone down? Well based on rough numbers I would say 5-7 mpg? As I stated earlier, this could simply be because I do carry more speed, more throttle here and there, etc. I guess I'll have to "baby" a tank or two just to see where I stand. That should give a better, more realistic MPG rating.

Interesting pipe autopsy also! No wonder they're so heavy. If I replace them with aftermarket, maybe I'll get my 5 mpg's back!

[EVLXX]

I think your bike is probably just fine, and you probably only have your right hand to blame.

Why...

I get on average,

43+ mpg / hwy,

40 mpg / city,

38 mpg / spirited,

29- mpg / Hyper.

My best tank of gas was 48 mpg, and my worst was 23 mpg, and the only difference was my right hand.

[shovelstrokeed]

5-7 mpg could just be "winter blend" gas. You might also be seeing an increase from 5% ethanol to 10%. You are in PA and they probably are still on winter blend or using up remaining stocks. See what things are like in May.

[Iceman_40]

I think your bike is probably just fine, and you probably only have your right hand to blame.

Why...

I get on average,

43+ mpg / hwy,

40 mpg / city,

38 mpg / spirited,

29- mpg / Hyper.

My best tank of gas was 48 mpg, and my worst was 23 mpg, and the only difference was my right hand.

What year is your bike...???

I gotta get my PC3 tuned but your millage is WAY above mine... your "hyper" isn't far off my hwy... :icon_snooty:

[Two4One]

First off many thanks to those who have responded!

I am going to rule out the winter blend idea only because I was experiencing the same decrease at the end of last summer although that is an excellent observation and one I wouldn't even think of.

I am going to go with the "right hand to blame" theory until proven otherwise. I'll report back after the Deal's Gap trip. Chances are I'll be heavy handed there as well based on last year's Cherohala blasts!

[EVLXX]

I think your bike is probably just fine, and you probably only have your right hand to blame.

Why...

I get on average,

43+ mpg / hwy,

40 mpg / city,

38 mpg / spirited,

29- mpg / Hyper.

My best tank of gas was 48 mpg, and my worst was 23 mpg, and the only difference was my right hand.

What year is your bike...???

I gotta get my PC3 tuned but your millage is WAY above mine... your "hyper" isn't far off my hwy... :icon_snooty:

99

If you didn't already now... I spent a TON of time building my own map for my PC2, and I really didn't get it all worked out until the end of last year.

I'm finally happy with it, even though it's still not perfect in my mind, but it's good enough.

A couple of weeks ago, we went on a ride, up and back down to the mountians, wife on the back. I got 50 mpg going up....... then only got 45 comeing down following alot of traffic. I say that because I'm trying to show you how much the bike LIKES to be loaded. On or off the throttle is fine, but floating the throttle down hill, when there's no load on the engine and you aren't decelerating or accelerating....... sucks down the gas.

I was able to fix some of that with my map at the end of last year, but not all of it. The stock ECU mapping has a weird glich in it.... and I couldn't get it all the way out with the PC.

PS. when I say Hyper driving.... I mean when my AVERAGE speed (for the hole tank of gas) was +100 mph.

The one time I had a 23 mpg fill-up... my Average speed over the 100 miles previous to that was 129.

Spirited riding to me is averaging inbetween 75 and 100.

My averageing includes everything from point A-B, that's slowing down through towns, and even those I think I thought I saw a Piggy events. Everything from take off to the next stop.

[Iceman_40]

Thanks for the info.

Any chance I can get a copy of your map?    It's useless for me to use but I'd like to get a idea of what you were playing with.

I'd really like to get my hands on a A/F meter/logger to install and play with.

[EVLXX]

Thanks for the info.

Any chance I can get a copy of your map? It's useless for me to use but I'd like to get a idea of what you were playing with.

I'd really like to get my hands on a A/F meter/logger to install and play with.

Give me some time and I'll see if I can show you.

[EVLXX]

Here is something for you to chew on...

Now keep in mind, this is not everything I have done... as there are 2 more screens that I didn't copy, and your not quite seeing the whole screen, but it's enough to get you thinking.

Plus I'll give you a hint.... MP... was the biggest key.

Enjoy.

[Iceman_40]

Wow the PC2 software is WAY different... seems like allot more to it.

I think I can only adjust the fuel...

What is the MP table?

[EVLXX]

Manifold Pressure.

There's a glitch in the stock programming at 2% TP. And it's this glitch that dumps fuel into the motor when your floating down the road. Hence the horrible gas mileage when coming down off the mountians when there's alot of floating.

So... I had to fool the stock ECU buy telling it there is pressure in the manifold... because nothing else worked.

And I wasn't able to fool it all the way. There wasn't enough correction available through the PC MP table. But it's much much better now.

When I say Dumping fuel... I mean like 10:1... like having the choke on.

You ever try to accelerate with the choke still on... it don't go. I found this was the big hick-up in mid corner throttle transitions.

Edited to add : The glitch is somewhere in between 2-5% TP.