Poor starting and erratic idle

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Poor starting and erratic idle

Postby stevei0220 » 03:51 am Jan 04 2013

Hi from the UK!
Been registered on here for a while but have only just got round to working on the 3 KDXs I now own! They've been sat in the garden shed and it has been suggested that I either do something with them or they will be disposed of... arn't women nice?

I have one that is currently road legal but it's a pig to start, has an erratic idle and seems to lack the "punch" I was expecting to find. She is the 200 SR and is recorded as being a 1991 model. From what I can make out she has a K&N filter and non-stock tail pipe. Whilst being nosey I found that there is no gasket on the left hand side KIPS cover, but otherwise all appears to be tight.

Some questions: Why is she a pig to start? Why does she settle to an idle that then rises without being touched? Would the missing KIPS gasket have an effect on any of this? Is unleaded fuel OK for her (91 RON) or should I go higher?
When she is running and being riden she goes and stops but she just feels as if she has lost her "sparkle". Your help and wise words would be most welcome.
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Poor starting and erratic idle

Postby thuginfc » 08:19 am Jan 04 2013

You said it was sitting for a while?

I'd start with cleaning carb the things they put in fuel now days gums up quick.

After that make sure there are no air leaks.

If its sat with gummed up kips valves it's possible they are stuck and need cleaning.
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Poor starting and erratic idle

Postby rbates9 » 09:20 am Jan 04 2013

Clean the carb. Don't be afraid to replace the jets while your in there if they look questionable. P.S. don't soak the carb in cleaner, just spray it out.

If that doesn't resolve the issues then might want to check the crank seals.
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Re: Poor starting and erratic idle

Postby suzuki 166 » 10:50 am Jan 04 2013

the 200 sr has a 28 mm carb this is why it will be down on power if you have an other kdx 200 swap the inlet manifold air box and carb and it will have loads more power you will have to do away with the auto lube and run on pre mix
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Re: Poor starting and erratic idle

Postby stevei0220 » 03:19 pm Jan 06 2013

Sorry for the delay in replying, but thanks for the comments. I have been surprised at the difference between parts used in my SR model and the other two bikes I had. Take for example, the air box set up. As I have said, the SR has fitted an oil soaked K&N filter fitted so I thought I'd might as well bin that and use a new Putoline filter I had. Well, the fittings are completely different and the Putoline filter and "cage" wouldn't fit into the SR airbox. So, I went to swap the whole unit over but then realised that the opening to the carb in the non-SR air box was considerably larger and so would no doubt cause further running problems by installing it. Back to the K&N, a bit of a clean and back it all went.

Had a quick look at the carb whilst things were taken apart and found the slide to have two worn areas, metal to metal friction wear by the looks of it. The rest of the carb was pretty clean. Installed everything, but found that the throttle was slow to return, it didn't have that "snap" I would have like to have seen. Tried to kick her over, only to find after three kicks that fuel was pissing out of the carb overflow pipes. It got to dark to contunue looking at things and since Friday I have had that man-flu thing that really hasnt inspired me to do anything but sleep and be grouchy with my family.
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