my fz6 seems restricted on power after it warms up

[tuningfork]

Check the engine coolant and inlet air temperature sensors as these are critical to proper air-fuel calculations. In fact check that the coolant system is working correctly (radiator level good, thermostat working, etc.)

This bike runs very clean emissions-wise so you should never really see any soot or smoke, especially if you do a lot of highway runs.

Those MPGs sound a bit low so it could be running rich, which would cause engine performance to decrease as it warms up. Could also need the CO adjustments checked. When was the last time you did a TB sync?

If your bike is stock I would not run premium fuel in it, you may be getting carbon buildup from the slow fuel burn and the 2005's lack of a fuel trim feature.

The dragging brakes check is also a great suggestion I have seen a few threads on here about sticky caliper pistons and if you ride in the rain and crud a lot, you most likely need to do some servicing.

 

[tuningfork]

Don't OD on the carb-cleaner especially in the tank, it can dislodge crud and send it into the filters, pump, and injectors. I pluged up my carbed bike quite bad once with too much seafoam in the tank, required a full carb servicing plus new spark plugs . If it is cruddy inside you need to pull it off the bike and flush it out.

 

[newbie001]

Check the engine coolant and inlet air temperature sensors as these are critical to proper air-fuel calculations. In fact check that the coolant system is working correctly (radiator level good, thermostat working, etc.)

This bike runs very clean emissions-wise so you should never really see any soot or smoke, especially if you do a lot of highway runs.

Those MPGs sound a bit low so it could be running rich, which would cause engine performance to decrease as it warms up. Could also need the CO adjustments checked. When was the last time you did a TB sync?

If your bike is stock I would not run premium fuel in it, you may be getting carbon buildup from the slow fuel burn and the 2005's lack of a fuel trim feature.

The dragging brakes check is also a great suggestion I have seen a few threads on here about sticky caliper pistons and if you ride in the rain and crud a lot, you most likely need to do some servicing.

Is CO adjustable on california models? I thought it is disabled in the diag mode, unless I am missing something.
I will do the TB sync again this weekend to see if that helps.

 

[newbie001]

Check the engine coolant and inlet air temperature sensors as these are critical to proper air-fuel calculations. In fact check that the coolant system is working correctly (radiator level good, thermostat working, etc.)

This bike runs very clean emissions-wise so you should never really see any soot or smoke, especially if you do a lot of highway runs.

Those MPGs sound a bit low so it could be running rich, which would cause engine performance to decrease as it warms up. Could also need the CO adjustments checked. When was the last time you did a TB sync?

If your bike is stock I would not run premium fuel in it, you may be getting carbon buildup from the slow fuel burn and the 2005's lack of a fuel trim feature.

The dragging brakes check is also a great suggestion I have seen a few threads on here about sticky caliper pistons and if you ride in the rain and crud a lot, you most likely need to do some servicing.

By the way , if I am getting carbon build up, where is it accumulating and how would I clear it up?

thanks

 

[RJ2112]

By the way , if I am getting carbon build up, where is it accumulating and how would I clear it up?

thanks

Generally,

Carbon build up will occur on the upper end of the cylinder walls,and the underside of the cylinder head. The parts that are not swept by the piston rings, can get a layer of tar built up on them.... with old low compression american V8's this would cause that dreaded 'death rattle' like in the Movie 'Uncle Buck'... the carbon deposits would stay hot enough after the engine was shut down, to provide a point of ignition for the fuel air still being drawn into the engine... the motor would 'diesel', due to the 'glow plug' like effect of the carbon.

With FI, the fuel source is shut off with the ignition.... there is no fuel to combust, so the process is much more controlled than with carbs. Pretty much unheard of, anymore...... turn off the motor, it stops. Wasn't that way, 30 years ago.....

That carbon will decrease the volume of the combustion chambers.... raising the engine's compression. Not enough 'swirl' due to hard running will increase the chance of this occurring. You can get rougher running on cheap gas, due to the higher chance of pre-ignition. The solution is to wring it out once in a while. Honest.... it'll pull 50 in first, without any undue stress.:thumbup:

The more I think about your situation, the more I suspect it's not getting to the 'standard' map, when the engine warms up..... the best indicator would be if you can smell any fuel in the exhaust after it's warmed up. (but maybe the cat's good enough to burn that all off, too.....)

I have to assume you are getting temperature indications on the display, showing the engine temp coming up as the bike warms, right?

Knowing your bike is similar to the one I had, (mine was an '05) when the bike starts, you can see the last two blocks of the LCD tach band blinking, right?

I recall someone here mentioning that the engine has reached op temp when those 2 blocks go solid.... worked for me. Don't hammer it until the last two blocks go solid.:rockon:

The bars of the temp gauge don't show up immediately, but over the first 5-6 minutes in cold weather, they'll start to come on..... mine used to indicate 3 or 4 bars typically when it was at full temp. I'd hear the fan come on whenever it hit more than that.

Can you describe what's 'typical' for your use?

 

[Jez]

I've just had a similar problem which we traced to corroded contacts in the relay/fuse box under the seat.

http://www.600riders.com/forum/garage-mechanical-help/29706-bogging-down-loss-power.html

 

[newbie001]

Generally,

Carbon build up will occur on the upper end of the cylinder walls,and the underside of the cylinder head. The parts that are not swept by the piston rings, can get a layer of tar built up on them.... with old low compression american V8's this would cause that dreaded 'death rattle' like in the Movie 'Uncle Buck'... the carbon deposits would stay hot enough after the engine was shut down, to provide a point of ignition for the fuel air still being drawn into the engine... the motor would 'diesel', due to the 'glow plug' like effect of the carbon.

With FI, the fuel source is shut off with the ignition.... there is no fuel to combust, so the process is much more controlled than with carbs. Pretty much unheard of, anymore...... turn off the motor, it stops. Wasn't that way, 30 years ago.....

That carbon will decrease the volume of the combustion chambers.... raising the engine's compression. Not enough 'swirl' due to hard running will increase the chance of this occurring. You can get rougher running on cheap gas, due to the higher chance of pre-ignition. The solution is to wring it out once in a while. Honest.... it'll pull 50 in first, without any undue stress.:thumbup:

The more I think about your situation, the more I suspect it's not getting to the 'standard' map, when the engine warms up..... the best indicator would be if you can smell any fuel in the exhaust after it's warmed up. (but maybe the cat's good enough to burn that all off, too.....)

I have to assume you are getting temperature indications on the display, showing the engine temp coming up as the bike warms, right?

Knowing your bike is similar to the one I had, (mine was an '05) when the bike starts, you can see the last two blocks of the LCD tach band blinking, right?

I recall someone here mentioning that the engine has reached op temp when those 2 blocks go solid.... worked for me. Don't hammer it until the last two blocks go solid.:rockon:

The bars of the temp gauge don't show up immediately, but over the first 5-6 minutes in cold weather, they'll start to come on..... mine used to indicate 3 or 4 bars typically when it was at full temp. I'd hear the fan come on whenever it hit more than that.

Can you describe what's 'typical' for your use?

yes, as bike warms up my temp gauge shows more bars; ( in city with traffic and me not splitting lanes, the temp can go high and then fan kicks in, so I think coolant/engine temp. indicator is working);
I tried to wait till those 2 blocks of temp go solid as well;
usually I wait about 1-2 mins till first temp bar is up, it worked fine before;
I can hear high rpms while it is still cold ( the fast idle unit helping to add extra air/fuel), then once the fast idle shuts off and rpms go to normal idle ( 1250-1300), I take off;

yesterday, went to ride again to listen to it closely; I put 3oz of seafoam in a tank; seems from 5000 to 7000rpms the engine effort and handlebar vibrations are the greatest; bike was going 100mph -- isn't it the indicator the motor was getting enough fuel? I gave it good revs going about 80mph in 3rd, and 50-60mph in 2nd;

Had a question, what is the color of ceramic area of spark plug supposed to be with good fuel/air mixture after 10k miles?

And I am till waiting for that morgan carb tune II from UK to check the TB sync;


thanks for new ideas.

 

[newbie001]

I've just had a similar problem which we traced to corroded contacts in the relay/fuse box under the seat.

http://www.600riders.com/forum/garage-mechanical-help/29706-bogging-down-loss-power.html

thanks Jez.

My rpms are very stable though, and I have not had electrical problems yet;
I wil check out that area though behind the left cover to see if anything is different ( I used that side to add the switch 'ignition on' for my sound system amp through license plate light);

 

[RJ2112]

yes, as bike warms up my temp gauge shows more bars; ( in city with traffic and me not splitting lanes, the temp can go high and then fan kicks in, so I think coolant/engine temp. indicator is working);
I tried to wait till those 2 blocks of temp go solid as well;
usually I wait about 1-2 mins till first temp bar is up, it worked fine before;
I can hear high rpms while it is still cold ( the fast idle unit helping to add extra air/fuel), then once the fast idle shuts off and rpms go to normal idle ( 1250-1300), I take off;

yesterday, went to ride again to listen to it closely; I put 3oz of seafoam in a tank; seems from 5000 to 7000rpms the engine effort and handlebar vibrations are the greatest; bike was going 100mph -- isn't it the indicator the motor was getting enough fuel? I gave it good revs going about 80mph in 3rd, and 50-60mph in 2nd;

Had a question, what is the color of ceramic area of spark plug supposed to be with good fuel/air mixture after 10k miles?

And I am till waiting for that morgan carb tune II from UK to check the TB sync;


thanks for new ideas.

The important part for me, is whether the bike has 'normal' engine performance while it's cold, and then does it bog down when it warms up?

With perfect combustion, the ceramic insulator should be a light tan color, to nearly the white that they were, new. (I think too much effort is put into this facet of diagnosis, to be honest.... as long as they are not covered in goop, and blackened from the build up of fuel by products, they are doing their job.)

The insulator is supposed to retain a specific range or heat, to burn off those deposits. The reason this is important, is to ensure the correct spark path. The goop can short out the plug, at a point where the spark doesn't 'jump the gap' at the tip as it is supposed to.

NGK Spark Plugs USA

 

[tuningfork]

Not a FZ6 motor ( A mini cooper actually) but this is your engine on CARBON:

 

[tuningfork]

yes, as bike warms up my temp gauge shows more bars; ( in city with traffic and me not splitting lanes, the temp can go high and then fan kicks in, so I think coolant/engine temp. indicator is working);
I tried to wait till those 2 blocks of temp go solid as well;
usually I wait about 1-2 mins till first temp bar is up, it worked fine before;
I can hear high rpms while it is still cold ( the fast idle unit helping to add extra air/fuel), then once the fast idle shuts off and rpms go to normal idle ( 1250-1300), I take off;

yesterday, went to ride again to listen to it closely; I put 3oz of seafoam in a tank; seems from 5000 to 7000rpms the engine effort and handlebar vibrations are the greatest; bike was going 100mph -- isn't it the indicator the motor was getting enough fuel? I gave it good revs going about 80mph in 3rd, and 50-60mph in 2nd;

Had a question, what is the color of ceramic area of spark plug supposed to be with good fuel/air mixture after 10k miles?

And I am till waiting for that morgan carb tune II from UK to check the TB sync;


thanks for new ideas.

The coolant temp sensor is a single circuit meaning the same circuit is used for the instrument cluster and the ECU (some cars for example have two circuits)...so if your temp guage seems to be moving then it is probably workingto some extent. The service manual has a test process to check its resistance at specified temps though...might be worth doing to make sure what it reports for temp is actually correct. The fan uses a separate thermo switch I believe so those actions are independent. I wonder if the thermostat is slow or stuck, that could cause the bike to run hotter than normal.

 

[The Toecutter]

Dude you skipped a major suspect component in your diagnosis....The Catalytic convertor....just take it off,and secure the remaining exhaust so you can road test the bike....its gonna be EAR BUSTING LOUD... but i'm sure this is it from what all you've done so far and all the cleaners you have passed through it have made it worse....it sounds to me like it can't exhale...

 

[newbie001]

well, got my carbtune today; spend some time working with synchronizing screws and idle speed; revved it to 4000rpm and checked/slightly adjusted the sync at 4k as well; rechecked at idle and readjusted; pretty much set them as close to spec at idle (218mmHG) and within 10mmHG or so at 3500-4000rpm;

the bikes feels better and easier to accelerate, and breaths better; but now tank almost empty; will have to fill tank and see how it runs in different conditions, temperatures, loads; ( before it would run better with near empty tank too sometimes, but today the feel was different -- better);

so now I am hoping that throttle bodies were not in normal sync or something and it was getting worse as bike was warming up;
( also I disconnected/ reconnected battery in a meantime as well to clear things as someone suggested);

It might be that due to poor sync, cylinders were working against each other , which caused noticeable extra effort , and extra heavy breathing/restriction;

in 3rd the machine would resist past 33-35mph to go faster; now seems like it wants to go without much effort past 50mph in 3rd;
same in 6th, after 60mph would show hesitance, now went to 115mph today after the sync, and bike seemed happy;

also, this tank still has some seafoam in it, so will observe it over next week -- weather permitting;

thanks

 

[wolfc70]

Not a FZ6 motor ( A mini cooper actually) but this is your engine on CARBON:

Neat pics!! That Mini engine is a DI (direct injection) engine though. These are a totally different beast compared to standard port injection engines. Since the fuel is injected directly into the cylinder, the fuel does not hit the intake valves. So any oil vapor (and combustion by-products) moving though the intake from the PCV system sticks to the intake valves, and since there is no fuel spray on the valves to clean them, they carbon up quickly. Some of the VW 2.0FSI engines have so much carbon that the valves will not close properly, causing misfires. Sometimes as early as 60k miles. It will be interesting to see how the manufacturers deal with this issue.

 

[tuningfork]

well, got my carbtune today; spend some time working with synchronizing screws and idle speed; revved it to 4000rpm and checked/slightly adjusted the sync at 4k as well; rechecked at idle and readjusted; pretty much set them as close to spec at idle (218mmHG) and within 10mmHG or so at 3500-4000rpm;

the bikes feels better and easier to accelerate, and breaths better; but now tank almost empty; will have to fill tank and see how it runs in different conditions, temperatures, loads; ( before it would run better with near empty tank too sometimes, but today the feel was different -- better);

so now I am hoping that throttle bodies were not in normal sync or something and it was getting worse as bike was warming up;
( also I disconnected/ reconnected battery in a meantime as well to clear things as someone suggested);

It might be that due to poor sync, cylinders were working against each other , which caused noticeable extra effort , and extra heavy breathing/restriction;

in 3rd the machine would resist past 33-35mph to go faster; now seems like it wants to go without much effort past 50mph in 3rd;
same in 6th, after 60mph would show hesitance, now went to 115mph today after the sync, and bike seemed happy;

also, this tank still has some seafoam in it, so will observe it over next week -- weather permitting;

thanks

GOOD WORK! :thumbup:

 

[newbie001]

does anyone know how many times those TBs can be synced,
when we turn adjusting screws clockwise? Is there a limit and what to do after that?

thanks

 

[RJ2112]

does anyone know how many times those TBs can be synced,
when we turn adjusting screws clockwise? Is there a limit and what to do after that?

thanks

You're effectively asking what happens when the screw falls out of the holes in the carbs........ but I suspect that would take counter clockwise rotation....

Screw them all the way in until they bottom out, then back them off two full rotations for a 'new' starting point. that gives you 2 turns 'in' to work with, as well as some number of turns 'out'. Probably shouldn't take more than 2 the other way..... but the folks that have synch'd their carbs should be able to answer that more accurately.

 

[newbie001]

well, sorry for confusion , but what I meant is when I screw them in clockwise the vacuum indicator is going up on my Carbtune Pro ( I set it to spec at 218mmHG or so);
so I am guessing at some point the screw will be in all the way;
Of course I still should be able to sync them to the same number but it may not be in the 218mmHG neighborhood.

 

[RJ2112]

well, sorry for confusion , but what I meant is when I screw them in clockwise the vacuum indicator is going up on my Carbtune Pro ( I set it to spec at 218mmHG or so);
so I am guessing at some point the screw will be in all the way;
Of course I still should be able to sync them to the same number but it may not be in the 218mmHG neighborhood.

My understanding is that it's more important that the readings be equal on all four cylinders, rather than a specific value..... don't get too wound up if you manage to get them equal at 220 mm HG, or some such. So long as you have them all as close to the same as you can get them, you're in good shape. Limit the change between cylinders' readings.

 

[tuningfork]

If you find you run out of adjustment range some day then its time for a valve adjustment, compression check, or a check for vacuum leaks around the TBs or hoses.