Fazer Owners Club - Unofficial

Bikes, Hints'n'Tips => FZS600 Fazer => Topic started by: unfazed on 06 July 2022, 10:28:55 pm

Title: Slow return to idle after closing the throttle
Post by: unfazed on 06 July 2022, 10:28:55 pm
For those chasing a slow return to Idle after closing the throttle on the FazersI had been chasing this slow return to idle on my 2003 Fazer 600 for a while and bike was a bit lazy on the throttle, response not as positive as it used to be. 
Everything checked out, nothing was wrong, I was totally baffled by it.
I took the carbs off to go through everything. Checked each of the diaphragms twice for holes and splits. Checked Inlet manifolds, and all vacuum caps, all were fine.
Evertyhing was absolutely as it should be
When putting the carbs back I was looking at how the air equalises at the top of the diaphragms. Removed the little gauze filter housing which allows the air to the vents in and out as slide rises and fals. Looked at it and it looked fine. Stuck a small LED light into the the back and could only see a few specks of light through it. Decided to try cleaning it and used Carb cleaner and an old beard trimmer brush as I could not remove the gauze.
See pictures of location of filter, what it looks like off the bike, plus the before cleaning and after cleaning. Bike is back running like new since and throttle response is back to normal. My theory was that since it couldn't breath in and out through the vents it was using the small holes on the base of the slide near the needles to equalise the air above the diaphragm and was slowing the rate of ascent and decent of the slide. It happened so gradually it wasn't notice. I have since checked my sons 600 and my 1000 and both were partially blocked. Cleaning these also improved the throttle response. My 600 has 955000 miles on it and both my sons 600 and my 1000 have about half that.
Title: Re: Slow return to idle after closing the throttle
Post by: Trebus on 07 July 2022, 12:15:38 pm
Thanks Unfazed, excellent bit of knowledge.
Title: Re: Slow return to idle after closing the throttle
Post by: beuleux on 07 July 2022, 01:09:31 pm
Useful info if anyone else comes across this problem, not an obvious thing. Thanks for sharing 👍
Title: Re: Slow return to idle after closing the throttle
Post by: fazerscotty on 07 July 2022, 02:18:21 pm
Nicely found - I'm wondering if these could be cleaned in an ultrasonic cleaner.
Title: Re: Slow return to idle after closing the throttle
Post by: Dave48 on 07 July 2022, 07:54:42 pm
Don't see why they shouldn't be safe in an ultrasonic cleaner. Maybe use a mild detergent solution. I am more than happy with mine and it cleans some very delicate components no problem
Title: Re: Slow return to idle after closing the throttle
Post by: robbo on 07 July 2022, 10:31:40 pm
Excellent fault finding unfazed, thanks for sharing :thumbup
Title: Re: Slow return to idle after closing the throttle
Post by: unfazed on 07 July 2022, 10:55:32 pm
I must put it up on the Facebook group as some members there are not on this forum.
Title: Re: Slow return to idle after closing the throttle
Post by: FazThou on 08 July 2022, 02:39:36 pm
Another great piece of advice
Well done unfazed
Title: Re: Slow return to idle after closing the throttle
Post by: Kenyun on 11 July 2022, 07:11:49 pm
 Nine hundred and fifty five thousand miles!!!!...no wonder it was feeling a bit lazy, poor old thing. :lol
Title: Re: Slow return to idle after closing the throttle
Post by: unfazed on 11 July 2022, 10:55:48 pm
Nine hundred and fifty five thousand miles!!!!...no wonder it was feeling a bit lazy, poor old thing. :lol
That's what I thought also :lol :lol
Title: Re: Slow return to idle after closing the throttle
Post by: b1k3rdude on 12 July 2022, 12:55:10 pm
Added link to FAQ.
Title: Re: Slow return to idle after closing the throttle
Post by: unfazed on 13 July 2022, 10:17:32 am
For those chasing a slow return to Idle after closing the throttle on the FazersI had been chasing this slow return to idle on my 2003 Fazer 600 for a while and bike was a bit lazy on the throttle, response not as positive as it used to be. 
Everything checked out, nothing was wrong, I was totally baffled by it.
I took the carbs off to go through everything. Checked each of the diaphragms twice for holes and splits. Checked Inlet manifolds, and all vacuum caps, all were fine.
Evertyhing was absolutely as it should be
When putting the carbs back I was looking at how the air equalises at the top of the diaphragms. Removed the little gauze filter housing which allows the air to the vents in and out as slide rises and fals. Looked at it and it looked fine. Stuck a small LED light into the the back and could only see a few specks of light through it. Decided to try cleaning it and used Carb cleaner and an old beard trimmer brush as I could not remove the gauze.
See pictures of location of filter, what it looks like off the bike, plus the before cleaning and after cleaning. Bike is back running like new since and throttle response is back to normal. My theory was that since it couldn't breath in and out through the vents it was using the small holes on the base of the slide near the needles to equalise the air above the diaphragm and was slowing the rate of ascent and decent of the slide. It happened so gradually it wasn't notice. I have since checked my sons 600 and my 1000 and both were partially blocked. Cleaning these also improved the throttle response. My 600 has 955000 miles on it and both my sons 600 and my 1000 have about half that.
Just to Add to this There are two slightly smaller similar filters on the 1000 one for carbs1 & 2  and one for carbs 3 & 4
I did not have the 1000 out until last Sunday, but  knew from the throttle response  after starting it when I had refitted the filters after cleaning them if was much impoived. What a difference it made to riding the bike, so much so even my wife noticed the difference and asked what I did to the bike since it felt like it was mad to go. It took me a while to get used to the throttle response. The full effect of Ivan's kit modification were finally unleashed :lol