Date: 26-10-25  Time: 20:38 pm

Author Topic: Coldstart tuning  (Read 2018 times)

Jamieg285

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Coldstart tuning
« on: 13 May 2016, 01:05:13 pm »
I'm on my second fazer now. The first one (2000) didn't have these symptoms and ran fine, so I know there is somehting not right about this one (2003)

In short, the bike struggles to run on cold startup without choke.  It doesn't need full choke, just enough to get it to idle above 900rpm.
Without choke it will start, but idles very low (600rpm and slowly drops) and will stall within a minute unless I intervene with a touch of throttle.   This is even now, when the weather is warm and it shouldn't need any choke. 

Once the bike has been run a while the idle is normal, approx 8-900rpm, so the idle adjustment is OK.

The bike is garaged, I replaced with new plugs a couple of months ago.  It has a K&N filter and a Scorpion exhaust (without baffle).

Any ideas?  Is there anything other than the idle speed I can adjust?


His Dudeness

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Re: Coldstart tuning
« Reply #1 on: 13 May 2016, 01:24:54 pm »
800 to 900RPM is too low. I'm surprised it can keep running that low. The manual says 1150 to 1250RPM.

BBROWN1664

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Re: Coldstart tuning
« Reply #2 on: 13 May 2016, 02:07:47 pm »
All FZS's are a little different. Some run much richer than others meaning less choke is needed. This can be down to non-standard air filters, different exhausts or even just age and general wear.

I wouldn't worry about it, just use a little choke to get it running and turn it off once your 1/2 a mile down the road.

Jamieg285

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Re: Coldstart tuning
« Reply #3 on: 13 May 2016, 03:21:26 pm »
800 to 900RPM is too low. I'm surprised it can keep running that low. The manual says 1150 to 1250RPM.

I didn't know that.  Perhaps all is fine then, I just need to tweek the idle speed up a bit.

darrsi

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Re: Coldstart tuning
« Reply #4 on: 13 May 2016, 07:09:43 pm »
I agree the idle is very low, turn it up to 1200rpm when the engine is warmed up and it will make a big difference.

Tony_c

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Re: Coldstart tuning
« Reply #5 on: 14 May 2016, 04:52:12 am »
My 2003 does the exact same thing and its standard air filter and factory exhaust. I always start it with a little choke.

Jamieg285

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Re: Coldstart tuning
« Reply #6 on: 16 May 2016, 12:31:04 pm »
Bumped it up to 1K when warm (sounds too fast  :D )

Seems to have sorted the problem.  Thanks all.

His Dudeness

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Re: Coldstart tuning
« Reply #7 on: 16 May 2016, 06:24:56 pm »
It's a motorbike not a car. Rev the nuts off it!