Extreme fuel usage after throttle body sync

[mave2911]

Hello my fellow forum participants.

I have a curly one for you. I am obsessive about maintenance with my bike, and do everything myself, if I can.

Unfortunately, I don't own a manometer, so just took my bike into Yamaha World here in Adelaide.

Again, unfortunately, they have a viewing window (I always watch when my bike is being serviced - always) and I noticed the 'mechanic' put the bike up on the lift, start it up and then start taking everything off to get at the tank. (inner fairing - which he couldn't find the two plastic screws under the mirror boots) and then, walk around the bike checking the brakes, fork seals etc.

Probably 20mins in, he jumped on the computer to try to figure out specific values (I'm guessing) and then plugged the doohickey in (not a fluid or magnetic manometer I'm familiar with) and then, as the throttle cable was apparently too tight, couldn't adjust anything.

It was at this stage, I went to the service department manager and said his mechanic was driving me nuts with his inefficiency and general dithering about.

The service manager came back to me and told me that essentially it was my fault because the throttle cables were too tight and the vacuum adjustment wasn't working. Now they had 'fixed' that, it was right to go.

As this took a bit over 45mins, they tried to charge me $70 - I said no way, you said it would (should!) be no more than $50.

Well, I fuelled up after the throttle body sync, and got 6L/100kms (39.2mpg), but as it has been idling on the bench for well over 30mins, I thought that seemed fair enough.

Since my fuel gauge seemed to be dropping quicker than normal, I just fuelled up again, and got 7.2L/100kms. (32.6mpg)

A new record by 1.2L/100kms (20%)

So, I rang the shop and they said they'd look at it - but if they find they've stuffed up, then who's to say they'll own that and not charge me?
More likely, they'll blame me again and charge me more.

Also, because the bike was idling on the bench for so long, with constant blipping of the throttle by the mechanic, my headers have really badly blued near the cylinders. (photo doesn't do it justice, but anyone that's seen my bike knows that I'm a bit obsessive)

SO, I have a two part question.

a) is this good enough?

b) is there anywhere else in Adelaide that someone would recommend I take my bike to and see a GOOD mechanic?

Cheers,
Rick

 

[Nelly]

Hello my fellow forum participants.

I have a curly one for you. I am obsessive about maintenance with my bike, and do everything myself, if I can.

Unfortunately, I don't own a manometer, so just took my bike into Yamaha World here in Adelaide.

Again, unfortunately, they have a viewing window (I always watch when my bike is being serviced - always) and I noticed the 'mechanic' put the bike up on the lift, start it up and then start taking everything off to get at the tank. (inner fairing - which he couldn't find the two plastic screws under the mirror boots) and then, walk around the bike checking the brakes, fork seals etc.

Probably 20mins in, he jumped on the computer to try to figure out specific values (I'm guessing) and then plugged the doohickey in (not a fluid or magnetic manometer I'm familiar with) and then, as the throttle cable was apparently too tight, couldn't adjust anything.

It was at this stage, I went to the service department manager and said his mechanic was driving me nuts with his inefficiency and general dithering about.

The service manager came back to me and told me that essentially it was my fault because the throttle cables were too tight and the vacuum adjustment wasn't working. Now they had 'fixed' that, it was right to go.

As this took a bit over 45mins, they tried to charge me $70 - I said no way, you said it would (should!) be no more than $50.

Well, I fuelled up after the throttle body sync, and got 6L/100kms (39.2mpg), but as it has been idling on the bench for well over 30mins, I thought that seemed fair enough.

Since my fuel gauge seemed to be dropping quicker than normal, I just fuelled up again, and got 7.2L/100kms. (32.6mpg)

A new record by 1.2L/100kms (20%)

So, I rang the shop and they said they'd look at it - but if they find they've stuffed up, then who's to say they'll own that and not charge me?
More likely, they'll blame me again and charge me more.

Also, because the bike was idling on the bench for so long, with constant blipping of the throttle by the mechanic, my headers have really badly blued near the cylinders. (photo doesn't do it justice, but anyone that's seen my bike knows that I'm a bit obsessive)

SO, I have a two part question.

a) is this good enough?

b) is there anywhere else in Adelaide that someone would recommend I take my bike to and see a GOOD mechanic?

Cheers,
Rick

Why not build your own manometer. There is a great thread about it.
Nelly

 

[stink989]

Unless the throttle was being held open by the tight cables I can't see how that would effect the balance at all. The machine I use is a digital type (vacuummate I think it's called) and is the same type used by Yamaha Australia, does an awsome job! Sounds like they deffinatly didn't do it properly and like they have no idea what they are doing with it. Can't recommend anywhere down your way sorry but wolfy might know a place that is good. If your ever in western nsw I'll do it for you the blipping the throttle part is a normal part of the process to let they settle back down after adjustment to see if more is needed.

 

[FinalImpact]

So what else could have changed when all is said and done? Any chance the fuel is different and now and has meth alc in it?

I say this because the minor change in AIR flow (that's what the misfit mechanic adjusted) is in use whether at idle or at 7000RPM so it doesn't really change the amount of fuel consumed until you change the engines speed.

Like you pointed out, the more idle time you have the less forward motion the bike recorded so it still burned fuel. However, at idle there is NO LOAD on the engine and its fuel demand is much less than pulling the same RPM doing work like moving you and it up a hill.

My vote is something else changed! Do you have a speedo healer which is now reporting incorrectly due to some other anomaly?

 

[TownsendsFJR1300]

Hello my fellow forum participants.

I have a curly one for you. I am obsessive about maintenance with my bike, and do everything myself, if I can.

Unfortunately, I don't own a manometer, so just took my bike into Yamaha World here in Adelaide.

Again, unfortunately, they have a viewing window (I always watch when my bike is being serviced - always) and I noticed the 'mechanic' put the bike up on the lift, start it up and then start taking everything off to get at the tank. (inner fairing - which he couldn't find the two plastic screws under the mirror boots) and then, walk around the bike checking the brakes, fork seals etc.

Probably 20mins in, he jumped on the computer to try to figure out specific values (I'm guessing) and then plugged the doohickey in (not a fluid or magnetic manometer I'm familiar with) and then, as the throttle cable was apparently too tight, couldn't adjust anything.

It was at this stage, I went to the service department manager and said his mechanic was driving me nuts with his inefficiency and general dithering about.

The service manager came back to me and told me that essentially it was my fault because the throttle cables were too tight and the vacuum adjustment wasn't working. Now they had 'fixed' that, it was right to go.

As this took a bit over 45mins, they tried to charge me $70 - I said no way, you said it would (should!) be no more than $50.

Well, I fuelled up after the throttle body sync, and got 6L/100kms (39.2mpg), but as it has been idling on the bench for well over 30mins, I thought that seemed fair enough.

Since my fuel gauge seemed to be dropping quicker than normal, I just fuelled up again, and got 7.2L/100kms. (32.6mpg)

A new record by 1.2L/100kms (20%)

So, I rang the shop and they said they'd look at it - but if they find they've stuffed up, then who's to say they'll own that and not charge me?
More likely, they'll blame me again and charge me more.

Also, because the bike was idling on the bench for so long, with constant blipping of the throttle by the mechanic, my headers have really badly blued near the cylinders. (photo doesn't do it justice, but anyone that's seen my bike knows that I'm a bit obsessive)

SO, I have a two part question.

a) is this good enough?

b) is there anywhere else in Adelaide that someone would recommend I take my bike to and see a GOOD mechanic?

Cheers,
Rick

As long as the bike is idling at 1300 or so, they can do the sync. When I do mine I have a large industrial fan that I turn on high and its placed directly in front of the headers.

I think it would behoove you to invest in a sync tool.. I have and would highly recommend a Morgan Carbtune Manometer which does NOT use fluids.

Morgan Carbtune - carburetor synchronizer for balancing motorcycle carbs


Its very accurate, extremly well made and very easy to use. The dealership down here charged me over $120 to sync my old FJR (a little more difficult to get to the vacuum ports than the FZ). the Carbtune was delivered to my door for about $85 (direct from England at the time) and has paid for itself many times over.

The FZ6 has actually 2 throttle bodies with a butterfly sync screw in the middle which is a NO NO to touch. You strictly sync with the air screws which are located on a block, under the tank on the left side. Yamaha allows for up to 10 MM's of difference in the balance, I played with mine until they were within 2-3 MM's, and thats also checking at 4,000 RPM's as I had a bit of vibration there. Fine tune syning it got rid of 90% of the vibes. If your mechanic screwed with the CENTER, THROTTLE BODY screw, that may be causing the reduced MPG's... I kinda doubt he did, but I personally would re-check WHERE EVER HE WAS AT..

I get around town about 46-47 MPG taking it fairly easy on the throttle, 40 sounds a bit low unless you changed your gearing. I do have a Speedohealer as well which sync with the GPS is DEAD on...

If you are mechanically inclined enough to raise the tank, you can sync it yourself, adjust the cables, etc yourself...

 

[Tailgate]

You gotta DIY or else, you don't know really what to think. Even then, you may not get a good answer but at least you can be sure to be sincere with yourself and take it from there. I can live with learning from my own mistakes (gulp).

 

[DefyInertia]

+1 on buying the tool. You just paid the shop the same amount it costs to buy the tool.

I bet the mechanic loved you.

 

[Nelly]

+1 on buying the tool. You just paid the shop the same amount it costs to buy the tool.

I bet the mechanic loved you.

Ouch........
Reminds me of a quote I heard somewhere?
"Don't pay a tool to molest your bike"

 

[mave2911]

I agree with the "Don't pay some tool to molest your bike", which is why I do all my own maintenance, but I didn't have a manometer, and as it's very irregularly you use one, and I got quoted $50, I figured I'd just get it done.

I'm bloody kicking myself now!

Cheers,
Rick

P.S. The cheapest I can get one for is $100, too - so getting it done was half the cost of buying.

 

[TownsendsFJR1300]

I later found on my FJR, when they synced the TB's, your suppossed to adjust them using vacuum screws as well (their just placed at each TB).

They, an authorized YAMAHA SHOP, adjusted ONE OF THE BUTTERFLY SCREWS (which again is a NO NO).
I know this as the white spot of paint, FROM THE FACTORY, was broke (on the butterfly adjuster spring) and the butterfly screw turned approx 1/4 turn..

BTW, theY chipped the frame paint on the upper left side (no extra charge!!)

Once I got my Morgan Carbtune, I put the screw back to stock and re-synced the bike (ran good before, ran a little better after my re-sync).

I was charged approx $120 for this. The bike still didn't run right. The shop literally spent hours looking, on the phone with Yamaha in Ca, but couldn't find the problem.

To add insult to injury, I eventually had another mechanic come out and tell me the occassional bog is NORMAL. I politly told him The bike hadn't done this the previous 6,000 miles nor did any other 4 cylinder bike I've owned. I told him he didn't know what he was talking about and to please leave (I was being polite but sturn), he left...

Doing a search on an FJR internet, I found the problem. A connector under the fuel tank likes to collect water and corrode. I pulled mine apart, sure enough, nice and green... Cleaned it up, a bunch of di-lectric grease, PROBLEM GONE!

I have other horror stories with my old Goldwing and an inept mechanic and Honda themselves trying to walk away and blame the mechanic as well (for a new oil leak). I had another dealership (1.5. hours away) fix it and charge me if needed and I'd just sue everyone, the original dealership and Honda.

They found the screw ups (several via the mechainc), Honda did pick up the bill after some threatening... I won't own a Honda again, (just because the way they treated me after one of their dealerships screwed me), period...

Point being, the more you know about your bike, the better...

On occassion, you'll find someone that is familiar with your bike and cares about their work/your bike but, I've found it to be rare...

 

[FinalImpact]

Scott,
What actually makes any sense in all of this about added fuel consumption? Ideas??

Adjusting the air bleed screw is not going to drop it as it did here (drastic).

Rick,
How does it actually run? Does it seem to run smooth, accelerate ect, idle . . .

 

[mave2911]

It seems to run ok, so I don't know.

One possible theory is that, if the mechanic stuffed it up completely and left one or two of the butterflies almost closed, that would mean that the other cylinders are doing all the work, but you'd need to crank the throttle

If it's running over rich, then that would go some way to explaining it, no?

Cheers,
Rick

 

[FinalImpact]

It seems to run ok, so I don't know.

One possible theory is that, if the mechanic stuffed it up completely and left one or two of the butterflies almost closed, that would mean that the other cylinders are doing all the work, but you'd need to crank the throttle

If it's running over rich, then that would go some way to explaining it, no?

Cheers,
Rick

Stuffed it up? As in loaded it up by running too rich? I'm not following you here. But if you mean too much idle time and has since fouled a plug, well that would hurt MPG. but it would very likely also be noticed as hesitation, stumble, slow to accelerate, misfiring, etc. You don't feel any of those so I'm goin to say nay on that.

No. The impact would be idle, off idle to maybe 3k or less and after that it would have no perceivable impact. Based on the fact that you are moving during 95% of its run time. Now if you idled for 95% of the time, ya idle tune is important, throttle plates, air rates, all that hoopla. . .

In this recent event, is there anything that could have messed up the odometer and the mpg is fine but the distance traveled is LOW? Did he put in kind of additive in the fuel that you witnessed or were charged for?

 

[TownsendsFJR1300]

I think "stuffed it up" as in f...ked it up.

I think he needs to ride it some more and document the mileage for the next tank or two.

If he adjusted the butterflys and not the air screws, that would make a fairly big difference depending on far out they are. At say, 4k RPM's (an average speed for me around town, about 50 MPH), those butterflys would normally just be cracked. If there out enough, two of the four cylinders will pull considerably harder than the other two, not very efficient... WOT, it wouldn't make much if any difference.

Did the mechanic put the vacuum caps back on after the sync, leave something off or disconnected, who knows...

I would like to see the final sync they left him with.

As stated in my earlier post, Yamaha usually puts just a small dab of white paint on that adjuster/butterfly sync screw. It wouldn't be hard to see if it has been adjusted.

I'm sure you know, it doesn't take 1/2 hour to sync the TB's with the block right there. It doesn't take long to adjust the throttle cables either, especially with the tank up, everythings right there...

 

[FinalImpact]

I think "stuffed it up" as in f...ked it up.

I think he needs to ride it some more and document the mileage for the next tank or two.

If he adjusted the butterflys and not the air screws, that would make a fairly big difference depending on far out they are. At say, 4k RPM's (an average speed for me around town, about 50 MPH), those butterflys would normally just be cracked. If there out enough, two of the four cylinders will pull considerably harder than the other two, not very efficient... WOT, it wouldn't make much if any difference.

Did the mechanic put the vacuum caps back on after the sync, leave something off or disconnected, who knows...

I would like to see the final sync they left him with.

As stated in my earlier post, Yamaha usually puts just a small dab of white paint on that adjuster/butterfly sync screw. It wouldn't be hard to see if it has been adjusted.

I'm sure you know, it doesn't take 1/2 hour to sync the TB's with the block right there. It doesn't take long to adjust the throttle cables either, especially with the tank up, everythings right there...

if the guy was **DUMB** enough to do that, it'd vibrate like hell! I don't think he messed with the shaft separating the TBs. Tho it would explain taking FOREVER to get sync as that would make "mission impossible!"

 

[TownsendsFJR1300]

if the guy was **DUMB** enough to do that, it'd vibrate like hell! I don't think he messed with the shaft separating the TBs. Tho it would explain taking FOREVER to get sync as that would make "mission impossible!"

I would hope he didn't but I know as fact, a Yamaha mechanic did exactly that on my FJR when it was still under warranty. You could see where the paint spot was broken. The FJR manual, DOES NOT WANT any messing with those butterfly screws. The screws for the FJR are much more accessable than the FZ in that the FZ, you likely have to remove the air filter (I do not know that as fact as I haven't tried to adjust that butterfly on the FZ) to get to it.

As for vibration, not necessarily. My FJR did not vibrate excessivly although they only turned that one butterfly screw, between #1 and #2 TB's maybe a 1/4 turn.. I retuned the crew back to the stock position and re-synced the TB's, agian with in 3-4 MM's...

On my Yamaha F150, 4 stroke OB engine, also Fuel injected, two TB's, 4 butterfly's, one adjuster screw between both bodies (all the same as the FZ6 but no air screw adjusters) AND NO AIR screws, all there is to adjust, for a sync, IS THAT ONE butterfly screw... The butterflys are pretty much closed fully at idle, a separate idle part
(forgot the name), via the ECU controls the air flow, idle RPM, etc in conjunction with the TPS (very similar to the Yamaha MC's)...

 

[FinalImpact]

You gotta pull the air box cause its titled back about the same angle as the cylinders IIRC.

 

[FinalImpact]

Matter of fact:
Ya, so if you Zoomify, you can see the white paint and how it all aligns.
View attachment 43400 View attachment 43401

Maybe I'll upload some of these into the bike P o r n album in case we need to view them later. . .

 

[pantone]

Make sure the black pipe plug is inserted sufficiently into the rubber pipe(a total of 4) to prevent vacuum leak. If it does not improve, maybe you need to synchronize it again.

 

[bob808]

I had a problem with the fuel consumption being 7l/100km and it sorted itself out after I disconnected the battery. I was on my way to the seaside, early morning, cold air, new k&n airfilter and I thought it would be right to reset the whole system. It went down to 5.8L/100km.