Hesitation, surging and crap mpg.

[Lawrence]

Right, need to get this sorted now. It's got worse recently to the extent that it's hard work getting it past 70, it misfires constantly over 5k and even in neutral at 4k you can hear it's not running right.  It's also drinking fuel, and doing 100 miles/day it's getting expensive.  It's had new filters, plugs, caps, coils, carbs and still runs like a bag of shit. Tps has been checked and is ok. Battery voltage is steady at over 14v (I'll get an exact reading later).

What else can I try? I've got a gallon of petrol and some matches ready which I could try but hesitant to use those yet...

Ta

[Fazerider]

You're doing long trips so this is a long shot, but we are in the carb icing season. Worth a check of the carb heating circuit? At least it should be possible to blow through them without taking them off, they're a bugger to refit in cold weather.
Beyond that it is pointing to an ignition problem I guess.
Flooding carbs would make it hard to start, as would low compression. Fuel starvation would explain a lack of power, but that doesn't tally with high consumption and an exhaust full of soot.
Have you gone round all the electrical connections making sure they're clean and tight?
Make a careful inspection of the wiring harness too: check where flexes with the steering and look for places where it can vibrate and chafe against things... particularly near the ignitor box in the tail unit, that was where I had a wire break in the immobiliser wiring.
Failing that, I'd try a swap of ignitor box and, it pains me to say, the regulator/rectifier. (I have no idea how that caused Red98's problem!)

[dBfazer600]

Mine had a similar problem and went down the same road as you. In the end I did 3 jobs at once.

Rad flush second time.
K & N air filter to replace stock filter with 100 miles on it.
Carb clean took out all the jets and poked the hell out of em used a guitar string and socked in carb cleaner but took the rubber washers off em.
Make sure you clean and poke the hell out off the rad connection pipes on the carbs as well. As I was sure it was not helping and aided in the icing

Put it all back together and made sure everything was seated and air tight with no cracks in.

It did the job for mine

Daz

[darrsi]

You're doing long trips so this is a long shot, but we are in the carb icing season. Worth a check of the carb heating circuit? At least it should be possible to blow through them without taking them off, they're a bugger to refit in cold weather.
Beyond that it is pointing to an ignition problem I guess.
Flooding carbs would make it hard to start, as would low compression. Fuel starvation would explain a lack of power, but that doesn't tally with high consumption and an exhaust full of soot.
Have you gone round all the electrical connections making sure they're clean and tight?
Make a careful inspection of the wiring harness too: check where flexes with the steering and look for places where it can vibrate and chafe against things... particularly near the ignitor box in the tail unit, that was where I had a wire break in the immobiliser wiring.
Failing that, I'd try a swap of ignitor box and, it pains me to say, the regulator/rectifier. (I have no idea how that caused Red98's problem!)

This problem started when it was in really warm weather so i think carb icing can safely be ruled out.
When i had it the bike virtually came to a stop anyway, whereas his bike is still running, albeit roughly.


He's still describing symptoms of a faulty TPS to me........rough running, bad fuel consumption, misfiring, etc.

[Fazerider]

[quote author=Fazerider link=topic=10010.msg115752#msg115752 date=1386090888]

You're doing long trips so this is a long shot, but we are in the carb icing season. Worth a check of the carb heating circuit? At least it should be possible to blow through them without taking them off, they're a bugger to refit in cold weather.
Beyond that it is pointing to an ignition problem I guess.
Flooding carbs would make it hard to start, as would low compression. Fuel starvation would explain a lack of power, but that doesn't tally with high consumption and an exhaust full of soot.
Have you gone round all the electrical connections making sure they're clean and tight?
Make a careful inspection of the wiring harness too: check where flexes with the steering and look for places where it can vibrate and chafe against things... particularly near the ignitor box in the tail unit, that was where I had a wire break in the immobiliser wiring.
Failing that, I'd try a swap of ignitor box and, it pains me to say, the regulator/rectifier. (I have no idea how that caused Red98's problem!)

This problem started when it was in really warm weather so i think carb icing can safely be ruled out.
When i had it the bike virtually came to a stop anyway, whereas his bike is still running, albeit roughly.


He's still describing symptoms of a faulty TPS to me........rough running, bad fuel consumption, misfiring, etc.
[/quote]

I did say it was a long shot.
But the OP says it ran OK in lower gears and then started spluttering so it's not impossible that time was the relevant factor rather than the road speed... so there could be icing. He also said it's got worse since the summer... so it could be icing.
Since a test can be done in ten minutes by taking the little pipe off the right hand side of the radiator, blocking the rad outlet with a finger and undoing the filler cap to see if coolant pisses out of the hose or not, is it really an unreasonable thing to check?

[darrsi]

Stick 200-300ml of 99% Isopropyl Alcohol in a full tank of fuel, it will stop carb icing immediately by binding with any water and burning it as fuel, and it will lower the freezing point, stopping any icing occurring.
If it isn't that then it won't make the bike run any worse at all, the ratio is far too small and it's obviously highly flammable so just ignites as normal, plus it's tried and tested.....by me.


Note: It must be the 99% stuff, if you get the 70% version then you'll also add 30% water as well which will cause you even more problems instead.

[elbrownos]

Carb icing is nothing to do with water in the fuel. It's humidity in the air that freezes.
The air temperature drops as it expands through a restriction (the throttle butterfly)
Moisture condenses out of the air and freezes in the carb.
Not saying there's any harm in putting isopropyl alcohol in your fuel, but it won't help with carb icing.

[darrsi]

Carb icing is nothing to do with water in the fuel. It's humidity in the air that freezes.
The air temperature drops as it expands through a restriction (the throttle butterfly)
Moisture condenses out of the air and freezes in the carb.
Not saying there's any harm in putting isopropyl alcohol in your fuel, but it won't help with carb icing.

Erm.......yes it does.......100%.

[darrsi]

The main ingredient in Silkolene Pro FST is [color=rgb(68, 68, 68)]Isopropanol, which is basically the same gear as Isopropyl Alcohol and is the suggested additive to fuel for carb icing.[/color]
[color=rgb(68, 68, 68)]I tried this Silkolene stuff but they suggest a couple of capfuls in your tank, so it basically just doesn't work because the ratio to fuel is simply too small.[/color]
[color=rgb(68, 68, 68)]Perhaps if you put the 1% ratio (200ml) as i have said then it may help, but at around £15 a litre that's an expensive habit, although it does have the fancy name and packaging, if you like that sort of thing.[/color]
[color=rgb(68, 68, 68)]5 litres of Isopropyl is now £14.19 delivered so a much better alternative, and easier on the wallet.[/color]
[color=rgb(68, 68, 68)]Saying all that, i don't believe that Lawrence's bike has carb icing.[/color]
[color=rgb(68, 68, 68)]From experience when i first got my bike, it would suddenly run like a tractor, or as if it was running out of fuel (which it was in theory) and the odd thing was that it was exactly one mile away from my house at the same spot where it happened, 3 days in a row[/color]
[color=rgb(68, 68, 68)]I managed to keep it just about ticking over by keeping the revs high, but it was basically running like shite.[/color]
[color=rgb(68, 68, 68)]Luckily i phoned my mechanic and he knew the symptoms straight away and told me it would pass once the engine warmed up properly and heated the carbs, which it did after about 10 minutes ticking over at the roadside.[/color]
[color=rgb(68, 68, 68)]That's when i did some research, tried the Silkolene which helped a little bit but wasn't great, then bought the Isopropyl and that did work a treat, to the point where there were zero signs of icing ever again.[/color]
[color=rgb(68, 68, 68)]I have been putting it in my tank every winter, at 200ml per full tank (1% ratio) and never ever had it again since then. [/color]

[color=rgb(68, 68, 68)]So yes, my bike has a booze problem, but it keeps it running sweet so everybody's happy.[/color] :b 

[Lawrence]

TPS has been replaced (with the carbs) but I can always swap back to make sure.

From what I understand about carb icing it's mainly when the engine is cold and in cold weather.  When I'm leaving in the mornings now it's ~8C outside, my garage is around 15C and it does it constantly through my 1 1/4 hr commute.  Also I'm pretty sure the carb heating pipes are ok as one of the rubber joiners split recently on the way to work (thankfully about 3 minutes before I got there) and was leaking coolant.

Just checked the battery voltages, engine off it was 12.18, warm idling it was 14.03 and at 2500rpm (I don't want to piss my landlord of too much...) it increased a fraction to 14.06.  Are these ok?

As for electrical connectors, I'll see if I can take a look at lunchtime tomorrow.

[darrsi]

TPS has been replaced (with the carbs) but I can always swap back to make sure.

From what I understand about carb icing it's mainly when the engine is cold and in cold weather.  When I'm leaving in the mornings now it's ~8C outside, my garage is around 15C and it does it constantly through my 1 1/4 hr commute.  Also I'm pretty sure the carb heating pipes are ok as one of the rubber joiners split recently on the way to work (thankfully about 3 minutes before I got there) and was leaking coolant.

Just checked the battery voltages, engine off it was 12.18, warm idling it was 14.03 and at 2500rpm (I don't want to piss my landlord of too much...) it increased a fraction to 14.06.  Are these ok?

My TPS broke down very gradually, rather than just stopped working one day, and it was only because a couple of other people were showing symptoms as well on here that i even got to learn about it.
Just before i changed it though the bike ran a bit lumpy and erratic, it was all a bit random really, it wasn't major but definitely not right.
And after reading somewhere earlier that it can cause fuel consumption problems i thought it all sounded a bit familiar that was all.
I randomly checked it a while back 'cos the bike didn't feel quite right, and the positioning was actually off, so it is noticeable when they're not spot on.

[gryphongryphon]

Been having problems with stuttering on acceleration, eventually came to conclusion it was crap petrol, it started after I filled up from a particular petrol station.

[darrsi]

Been having problems with stuttering on acceleration, eventually came to conclusion it was crap petrol, it started after I filled up from a particular petrol station.

It's a possibility, but it can also be caused by several other things as well, air filter, air leak, blocked carb needles, blocked fuel filter, unbalanced carbs, etc......unfortunately nothing's that straight forward.  :'(

[Torque]

Been having problems with stuttering on acceleration, eventually came to conclusion it was crap petrol, it started after I filled up from a particular petrol station.

I've also got similar issue: [size=78%]http://foc-u.co.uk/index.php/topic,10534[/size]


I think I've checked everything I could and I think that my issue could be fuel related.
I've replaced the fuel, it did not help, however I think it could be because my tank have drain pipe blocked (only breather pipe is connected to hose).


Now waiting for Isopropylene to add some to get the water from inside of the tank.

[Lawrence]

Don't think bad petrol is the case for me, I do a tank in two days (13 litres/day at the moment, ~35mpg :'(), have use several different petrol stations and have even tried super in it.

Swapped the plugs out for the old ones that were removed a couple of months back and there's no change.  The plugs that came out are completely black.

I didn't get this before it started running like total shite so I'm very tempted to swap the original carbs back on.

[Lawrence]

Just a thought, could a dying battery cause misfiring like this? I'd have thought it's be running off the generator over a couple of k rpm, but it wouldn't start this morning (turned over, but slowly) and needed 5 mins on a charger to get going.

[Dead Eye]

The electrical circuit doesn't work like that on the Fazers due to how the current / voltage is delivered to the battery. If the battery is knackered, it will read closer to full and the reg/rec will dump the excess current to ground (that's what its supposed to do).

The battery numbers listed previously didn't seem awful, but maybe a tad low. Might be worth seeing if there is anyone local you can do a quick swap with... I would have, but I'm not local anymore If its still the case, I'd try the reg/rec as well - just in case

[His Dudeness]

The electrical circuit doesn't work like that on the Fazers due to how the current / voltage is delivered to the battery. If the battery is knackered, it will read closer to full and the reg/rec will dump the excess current to ground (that's what its supposed to do).

The battery numbers listed previously didn't seem awful, but maybe a tad low. Might be worth seeing if there is anyone local you can do a quick swap with... I would have, but I'm not local anymore If its still the case, I'd try the reg/rec as well - just in case

I see from your post you got a thou    How does it compare to the 600?

[gryphongryphon]

Just sorted my Fazer from stuttering and hesitation , it was a coil, I detected it by pull off plug leads at idle 1 at a time, 2 and 3 when removed one at once the hardly caused a deterioration in idling.When I pulled off 1 or 4 plug cap, engine at idle speed nearly stalled. So changed coil to plugs 2 and 3 , problem solved ,genuinely runs better than ever because it has had a slight stutter from low revs ever since I have owned it.

[Lawrence]

I've changed coils already, I thought they might've been ok at low revs and unable to provide enough juice to spark at high revs but it made no difference :/  I'm going to get the reg/rec and cdi off today and see if I can get them tested at my local dealer.