Rough Idle - with video

[GosportFazer]

Hey chaps,


Bought my Boxeye in January after righting off the last bike, and have had a pretty rough idle from the start. It's irritating but not terminal - the bike still revs freely and runs fine in traffic, but the idle hunts and sounds rough as.


I have replaced the plugs - no difference
checked the Coils and plug caps (chopped 10mm of the leads at the time) - All in spec
looked at the airfilter (seems cleanish - better than most),
checked the TPS  - in spec
and balanced the carbs (this made the bike run a lot smoother in traffic - but hasn't solved the idle).


I have covered nearly 2000 miles since buying the bike and had hoped it would clear itself. Seeing as this isn't the case I'm thinking my next stop will be the carbs - and checking the inlet rubbers etc whilst I am at it. Come may bank holiday I have a week shutdown at work and so would like to buy anything necessary now in order to pull and properly sort it then. But I need to guarantee the bike will be on the road again the following week as it is my only transport to work.


So the big question is:


what do I need to service/sort this bike out including carb overhaul? Any products, special tools, gaskets, rebuild kits etc? is the air filter worth doing for the sake of it - or is that just wasting my money/effort?


Please take a look at the video of it idling I have uploaded to YouTube - maybe someone smarter than me will recognise the symptoms.


Fzs 600 Fazer - rough idle

[noggythenog]

Personally id be pretty happy with that pal.




I dont have a great bike knowledge but i would look at that big old analogue dash & dial & think thats pretty sweet.


I know it seems to jump about a smidge but then the engine is ticking over at its lowest point before conking out.....so if you set the idle a but higher ie put the choke on a little snidge then im willing to bet that it wont do it.......kinda like the biting point on a clutch just before you stall...up the revs a bit & it is fine.




Seems normal.






But i welcome more on this as im only sating what i feel rather than what i actually know.

[darrsi]

I would say it doesn't quite sound right, but the idle judging by the needle looked reasonable enough to me.
By the way you were explaining it I was expecting the needle to be jumping all over the place but it wasn't.

[red98]

Looking at the white smoke from the exhaust iam guessing its still cold, yes the needles moving a bit but not bad for first start up......you could try cleaning the carbs paying special attention to the pilot jets........nothing needed just basic tools.

[GosportFazer]

Like I said - not fatal, but irritating as you like. Sounds like an occasional miss, and ruins the bikes appeal when waiting in traffic.


If I up the idle speed, it doesn't vanish, even holding the throttle on up to about 2500 you can still (greatly reduced) detect it, but certainly at anything below 1600 its obviously there.


I really would love to get it running as smooth as possible - I can't believe that it is not doable. My last bike - a gpz500 sounded like a bag of nails when first started, but it idled rock solid once warm.


edit: The bike hadn't been used in two hours, so I started it and left it to run for about 10 mins or so before taking the video. Not perfect, but the idle doesn't really change much from what it shows.

[johna6968]

I did expect a lot worse before watching the video..

[Fazerider]

For about £8 you can get an infra-red temperature gun which can be useful for checking to see which cylinder is running a bit cooler (though you may also be able to judge by comparing how fast water evaporates off the pipes when you wet them).
Another thing you can do is check the fuel levels in the carb float bowls: shove a transparent tube over the drain spigot and held up to form a U will show the level when you open the drain screw.
Those might give a clue as to where the problem is.

Other things you can do that might help (without involving much dismantling) include a check that the choke plungers all move OK…  and experimenting with the mixture screws, try resetting them to 2 turns out, see if there's any improvement, if not, try winding them out a quarter turn and repeat. Factory setting seems to be about 2.5 turns, some find 4 or 5 turns is what theirs like. The carb for cylinder 3 is a pain to get at, removing the starter motor helps access.

If it may well be that the carbs just need a clean, you shouldn't need any bits just to open and reassemble them, the float bowl seals are synthetic rubber and mine have always been reusable. If water has got in the fuel system there's a good chance there will be plenty of rusty crud built up around the needle valve… the mixture of water, steel, brass and zinc alloy guarantees corrosion.

[Buzz]

That's what mine sounds like and I know that cylinder 3 runs cooler at idle.  5 mins after startup I can still put my palm on 3 whereas 124 are at full temp.  Doesn't affect the running under power but I think the pilot jet on 3 is partially blocked.  It's one of those jobs I've been putting off for the past 2 years.

[fazersharp]

Sounds just fine to me --------------- only you need to turn the idle revs up a tiny tad and that shoud improve things it seems a little low which is giving you the "rough"

[dBfazer600]

I have been adding allot of extra electrical componenets on where I had heated grips and sat nav running from a piggy back fuse plugged into the ignition fuse. Bike was running a little off and not as smooth as usual but did not think anything off it until I swapped to the head light fuse and this settled  bike back to normal. I now run my Autocom from the ignition fuse. I have no idea why the bike is running better but it does.

Don't know if it relates to your situation but if you have extras hooked to the electrics take em off one at a time to see if this helps.

Daz

[His Dudeness]

That's what mine sounds like and I know that cylinder 3 runs cooler at idle.  5 mins after startup I can still put my palm on 3 whereas 124 are at full temp.  Doesn't affect the running under power but I think the pilot jet on 3 is partially blocked.  It's one of those jobs I've been putting off for the past 2 years.

I think if the jet was blocked it would run leaner and so hotter rather than cooler. If it's cooler it might be a weaker spark. For the bike in the video I'd do the water on the headers trick and get the infra red temp checker as Fazerrider said. Try and get a bit of evidence rather than chasing your own tail.

[GosportFazer]

Thanks for the suggestions everyone.  I have gone ahead and bought a new set of plug caps from eBay, at 1.99 each seems daft not to.
I'm at work atm on phone but once home I'll look into an infra red gun to check the headers temp at idle. Good to know I can dismantle and reassemble carbs without new seals. What does everyone use to clean out the jets? Guitar string? Air?

[fazersharp]

before you do any of that just turn up the idle i do think its a bit low

[johna6968]

Divided opinion on whether to change float bowl gaskets or not.. Me personally I would change them, particularly if they are the originals as once flattened and then disturbed can be prone to weeping..

[darrsi]

before you do any of that just turn up the idle i do think its a bit low

".....If I up the idle speed, it doesn't vanish, even holding the throttle on up to about 2500 you can still (greatly reduced) detect it, but certainly at anything below 1600 its obviously there....."

[Yamazer-92]

Sounds pretty normal to me, can't hear anything too awful put it that way. A few things I did to help mine at tick over and around and below 3k rpm were balance the carbs, check the tps, put some rubber from an old bicycle inner tube under each of the infill fairing screws to stop the bloody things buzzing and turned up the idle a tad to about 1250 or so as it was at about 1100. Has definitely improved it a bit, but its not a faultless burrrrrrr like a modern BMW S1000rr or something because its not a modern bike so I just accept that is how it is, it runs and rides fine. You can try and use some STP fuel cleaner before taking apart your carbs. I have also clipped my ht leads and got new spark plug caps, didnt really make a difference but worth doing for the price.

[johna6968]

put some rubber from an old bicycle inner tube under each of the infill fairing screws to stop the bloody things buzzing

Made some lovely anti buzz strips out of push bike inner tube too, to fit between fairing and support brackets directly under the mirrors.. Bloody buzzing was drivin me bananas.. Old Skool.. Proper  :thumbup

[darrsi]

[quote author=Yamazer-92 link=topic=12996.msg147035#msg147035 date=1399489553]
put some rubber from an old bicycle inner tube under each of the infill fairing screws to stop the bloody things buzzing

Made some lovely anti buzz strips out of push bike inner tube too, to fit between fairing and support brackets directly under the mirrors.. Bloody buzzing was drivin me bananas.. Old Skool.. Proper  :thumbup
[/quote]

Soft velcro works a treat too.

[His Dudeness]

Divided opinion on whether to change float bowl gaskets or not.. Me personally I would change them, particularly if they are the originals as once flattened and then disturbed can be prone to weeping..

I've had my bowls off probably 4 or 5 times and they're still fine

[wickedmonkey]

Not that it's much help but mine is a 98 box eye and runs very similar to this (slightly smoother with idle set to about 1300 RPM). Had the bike since Aug 2013 and have gotten used to it. While I would love to get it perfect, I fear that my mechanical incompetence would let me down and probably do more damage that good...


However, if you manage to get it smooth, please let us know what you did.