In addition to pistons, remove the pads & clean. Get a couple packettes of brake caliper lube and lube the slide points and pins. If the pads don't move freely it doesn't matter what the pistons do.
Gas Mileage dropping - no reason I can see
- Thread starter birkdale10
- Start date
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carlson_mn
Well-known member
Your brakes and bearings aren't causing your mpg drop. You'd probably smell the brake pad if it was hung up causing that much of a consistent drop over a tank of fuel.
Check for a vacuum leak perhaps if someone else was dinking around with your bike and airbox.
If the mpg is this considerable and consistent drop when cruising on the highway which would of course be in closed loop fueling mode, I'd look into seeing if the O2 sensor is going bad and reading lean. The computer will read that and tell the injectors to add more fuel to achieve the desired (false) AFR reading of the O2 sensor.
Check for a vacuum leak perhaps if someone else was dinking around with your bike and airbox.
If the mpg is this considerable and consistent drop when cruising on the highway which would of course be in closed loop fueling mode, I'd look into seeing if the O2 sensor is going bad and reading lean. The computer will read that and tell the injectors to add more fuel to achieve the desired (false) AFR reading of the O2 sensor.
RichDoyle
Well-known member
Just a related comment. Spring is here, along with the change in fuel blends. Gas mileage increasing for me as it does every year about this time.
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ANZAC
Well-known member
39mpg today - best tank ever in the Portlandia commuting grind. Love my 2003
Looking forward to my regular 40-42 smiles per gallon soonly.
sgreb
Member
I have an 06 that I bought last year... I average 34 mpg.... it came with a PC-V on it... I have no idea what map or type of map it has in it.... I do like to accelerate quickly and performance wise I think it runs great.... I am assuming that the mapping is maybe geared toward performance thus hurting the mpg...
RichDoyle
Well-known member
Now that summer is here my '13 has come up to a fairly solid 45 MPG for the riding I do. My Prius has bumped up to its typical summertime mileage as well. FWIW, gas mileage-wise these two vehicles are a wash. But fun-wise, excluding T-storms, etc., no contest.
birkdale10
Well-known member
Thought I'm make a 3rd update. First, actual factual decrease in gas mileage.
I bought the bike in Oct 2004. I created a spreadsheet back in 2005, and started using it 'seriously' in late 2005. I have kept track of every fill up I have put in the tank since then. MPG for every tankful, # of miles for every one, miles on reserve.
I started this thread in April. But May is now gone, and here is what I have. I looked at my spreadsheet, and took every fill up in May for every year since 2006.
All Mays: 2006 - 2103 average: 45.35mpg Best May: 2006: 46.94. Worst 2011: 43.44
May 2014 Average : 36.48mpg
My handy-dandy calculator tells me that is a 20% difference. I think...that is significant.
I have gotten in touch with the local Yamashop, but nothing has been decided yet.
There is one other piece of info that I hope someone will read and give me some helpful advice about. I went for a ride today - just a short one, 40 miles. After about 8 miles, I looked down and the yellow 'check engine' light was on. I have NEVER seen that lit before, other than when the bike starts. It stayed on for about 2 minutes, then went out. About 20 miles later, it came back on again for about 2 minutes, then went out.
I'm seriously starting to get worried about my bike.
I bought the bike in Oct 2004. I created a spreadsheet back in 2005, and started using it 'seriously' in late 2005. I have kept track of every fill up I have put in the tank since then. MPG for every tankful, # of miles for every one, miles on reserve.
I started this thread in April. But May is now gone, and here is what I have. I looked at my spreadsheet, and took every fill up in May for every year since 2006.
All Mays: 2006 - 2103 average: 45.35mpg Best May: 2006: 46.94. Worst 2011: 43.44
May 2014 Average : 36.48mpg
My handy-dandy calculator tells me that is a 20% difference. I think...that is significant.
I have gotten in touch with the local Yamashop, but nothing has been decided yet.
There is one other piece of info that I hope someone will read and give me some helpful advice about. I went for a ride today - just a short one, 40 miles. After about 8 miles, I looked down and the yellow 'check engine' light was on. I have NEVER seen that lit before, other than when the bike starts. It stayed on for about 2 minutes, then went out. About 20 miles later, it came back on again for about 2 minutes, then went out.
I'm seriously starting to get worried about my bike.
ANZAC
Well-known member
Check your electrical connections under the T-bar area for corrosion as my bike had intermittent high beam control until I cleaned the large white connector with CRC electrical cleaner.
Regarding fuel mileage - we are all seeing mileage drop due to ethanol in the gas which we did not have years ago. I am lucky to get 39mpg on my 2003 but then again she is used for commuting not long distance touring.
Regarding fuel mileage - we are all seeing mileage drop due to ethanol in the gas which we did not have years ago. I am lucky to get 39mpg on my 2003 but then again she is used for commuting not long distance touring.
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Hotboot
Well-known member
Good old D/FW summer fuel formulation. Like clockwork, mine drops every year around the end of May. You will notice less power too.
anjinsan
Member
My 2010 got 49.1 MPG on my trip back from Americade last week. Let us know how you make out
birkdale10
Well-known member
I took my bike to the Yamashop last Saturday (6/14/14). It is still there. I didn't realize until Monday the 16th that I missed the National Ride To Work day - for the first time since 1994. The only reason I missed it before that is because I was living in New Zealand.
But, the bike is in the shop, and I spoke at length with Service Manager, and mentioned a couple of things that others on this thread have suggested as possible worn out/malfunctioning parts. He told me that they are not 'parts replacers'. They are going to find out what is wrong before trying to fix it. OK. I respect that - that is the way a good mechanic works.
They have had it for 4 working days, and I called to ask. Well, they can't find anything wrong. They have taken it for rides and were trying things like hard acceleration, expecting it to cut out. That's not what I said was happening. I have a throttle lock, and I have been on a level straight road, and put that on to hold at 60mph. And sometimes it would just suddenly slow down suddenly, then catch back. Sometimes. Once an hour? Once in 30 minutes? Does anyone else also understand, as I do, that trying to figure out something that happens on a mechanical device sometimes is just about the most maddening, frustrating and time consuming thing to do?
The bottom line, for me, is that the MPG dropped from 45 to 36. I hammer away at that. This is MY mileage, not someone else's. I live in DFW, and, yes there is the summer fuel formulation that changes ever year in May. I am comparing apples to apples. I am comparing 7 years of AVERAGE MPG in the month of May, compared to this year's month of May.
I wish I knew of something to tell the mechanic working on it. And I wish I had my bike back. I really dislike commuting in a car.
I wish I could stop whining about it.
But, the bike is in the shop, and I spoke at length with Service Manager, and mentioned a couple of things that others on this thread have suggested as possible worn out/malfunctioning parts. He told me that they are not 'parts replacers'. They are going to find out what is wrong before trying to fix it. OK. I respect that - that is the way a good mechanic works.
They have had it for 4 working days, and I called to ask. Well, they can't find anything wrong. They have taken it for rides and were trying things like hard acceleration, expecting it to cut out. That's not what I said was happening. I have a throttle lock, and I have been on a level straight road, and put that on to hold at 60mph. And sometimes it would just suddenly slow down suddenly, then catch back. Sometimes. Once an hour? Once in 30 minutes? Does anyone else also understand, as I do, that trying to figure out something that happens on a mechanical device sometimes is just about the most maddening, frustrating and time consuming thing to do?
The bottom line, for me, is that the MPG dropped from 45 to 36. I hammer away at that. This is MY mileage, not someone else's. I live in DFW, and, yes there is the summer fuel formulation that changes ever year in May. I am comparing apples to apples. I am comparing 7 years of AVERAGE MPG in the month of May, compared to this year's month of May.
I wish I knew of something to tell the mechanic working on it. And I wish I had my bike back. I really dislike commuting in a car.
I wish I could stop whining about it.
Denver_FJR
Well-known member
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Hotboot
Well-known member
As I posted earlier, I'm sure your mileage drop is summer fuel blend, we run several vehicles in north texas and this year it is much lower. It never hurts to do proper maintenance but dont chase 5 mpg when it's not the bike.
carlson_mn
Well-known member
9mpg's is not 5mpg's. Keep us updated what they find. All I can do is ponder, but I have heard of things like leaking fuel injectors. If you're getting occasional cutting off from the bike I would worry if a spark plug is getting blasted by too much fuel temporarily. Eh, fun to speculate.
You need to get that bike re-tuned, or at the very least do some research on tweeking some of the fuel cell tables. PM me if interested I can help.
SoCalFJR1300
Well-known member
Have you tried running some fuel system cleaner through a tank or two of fuel?
Chevron with "Techron" works pretty good, cheap try even if it doesn't work.
Chevron with "Techron" works pretty good, cheap try even if it doesn't work.
RossKean
Well-known member
Do you have a Power Commander on the bike? A messed up unit (program or faulty) could cause problems with fuel consumption. If you have a PC, remove it and check mileage for a couple of tanks. O2 sensor was mentioned (above) as well - could be an issue.
Has the shop done any exhaust gas sniffing to determine fuel-to-air ratio? If you are burning excess fuel, the ratio will be off.
Has the shop done any exhaust gas sniffing to determine fuel-to-air ratio? If you are burning excess fuel, the ratio will be off.
birkdale10
Well-known member
I am adding more to my thread, which is getting longer.
My bike is still in the shop. I found out that the Irving Yamashop has a 2 week backlog. I took the bike in Jun 14, and it sat for 2 weeks before anyone looked at it. 'Looked at it' meaning that someone rode it for a while and didn't notice anything wrong. It idles, it accelerates, it stops and goes. They said it ran pretty good. I say it runs poorly, because I know what it is like when it is pretty good.
Obviously, they can't check the gas mileage from a 15 minute ride. The whole reason I took the bike there was for an expert to figure out why I'm getting 50 miles less per gallon of gas, and engine lights come on every now and then.
I am just about ready to go and get my bike back and take it somewhere else. Does anyone reading this live anywhere near the DFW area and know of someone qualified to work on an admittedly difficult to diagnose problem? There is another Yamaha ship in North Lewisville, and I don't know of any others. There are supposed to be private mechanics out there, unaffiliated with a dealership that sometimes do better work. Again - anyone! Do I have any good options for a bike mechanic in the DFW area?
And, btw, someone asked about a Power Commander on the bike. I'm not exactly sure what that is or what it does, but unless it's something that Yamaha put on the 2005 models as stock equipment, I don't have one.
My bike is still in the shop. I found out that the Irving Yamashop has a 2 week backlog. I took the bike in Jun 14, and it sat for 2 weeks before anyone looked at it. 'Looked at it' meaning that someone rode it for a while and didn't notice anything wrong. It idles, it accelerates, it stops and goes. They said it ran pretty good. I say it runs poorly, because I know what it is like when it is pretty good.
Obviously, they can't check the gas mileage from a 15 minute ride. The whole reason I took the bike there was for an expert to figure out why I'm getting 50 miles less per gallon of gas, and engine lights come on every now and then.
I am just about ready to go and get my bike back and take it somewhere else. Does anyone reading this live anywhere near the DFW area and know of someone qualified to work on an admittedly difficult to diagnose problem? There is another Yamaha ship in North Lewisville, and I don't know of any others. There are supposed to be private mechanics out there, unaffiliated with a dealership that sometimes do better work. Again - anyone! Do I have any good options for a bike mechanic in the DFW area?
And, btw, someone asked about a Power Commander on the bike. I'm not exactly sure what that is or what it does, but unless it's something that Yamaha put on the 2005 models as stock equipment, I don't have one.
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carlson_mn
Well-known member
I would take the bike back and get the O2 sensor tested by any local auto shop. Or just replace it if it's not too much. When they go, they fail lean, which is safe as the engine starts to dump more fuel than it really needs.
If you haven't owned the bike since new you can lift the tank and see if the PC module is installed in the factory fueling harness which is right on top of the engine basically. You'll know if it's there.
If you haven't owned the bike since new you can lift the tank and see if the PC module is installed in the factory fueling harness which is right on top of the engine basically. You'll know if it's there.
Or, if you suspect the O2 sensor is the culprit, try just unplugging the damn thing. The bike runs fine without it. It will never go into closed loop mode, which means it will run slightly richer than if it was hooked up, but not much. Certainly not 9-10 mpg different.
Everyone that has a Power Commander unplugs theirs. And then the PC dumps more fuel in on top of that and still hey only suffer by 3-4 mpg's at worst. But they run a lot smoother.
Everyone that has a Power Commander unplugs theirs. And then the PC dumps more fuel in on top of that and still hey only suffer by 3-4 mpg's at worst. But they run a lot smoother.
