Main jet?

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Symon94
Posts: 5
Joined: Sun Feb 10, 2013 3:39 pm
My Bike: Zxr 400

Main jet?

Post by Symon94 »

So my bike seems to have a stutter from around 10k to 14k, and I'm thinking its the main jet. I've replaced the spark plugs and air filter witch didn't work. And the carbs were balanced not long ago. Just wondering how hard is changing the main jet? It's it just removing the carb bowl and unsrewing the jet? Like on a 50cc carb or is it more complex? And where can I buy a set of jets? I'm looking at getting #102 but can't seem to find anywhere.
Cheers
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RedexRobB
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Joined: Fri Aug 30, 2002 7:37 pm
My Bike: ZXR400L3
Location: Ipswich, Suffolk

Re: Main jet?

Post by RedexRobB »

Pretty much that yes. Nothing overly complicated. You could try running some redex in the fuel and see if that clears things out a bit. Has it always stuttered or is it something that has happened recently. Has the bike been stood for a while?
ChowderV4
Posts: 98
Joined: Mon Dec 24, 2012 7:57 pm
My Bike: Zxr400L racer

Re: Main jet?

Post by ChowderV4 »

Symon94 wrote:So my bike seems to have a stutter from around 10k to 14k, and I'm thinking its the main jet. I've replaced the spark plugs and air filter witch didn't work. And the carbs were balanced not long ago. Just wondering how hard is changing the main jet? It's it just removing the carb bowl and unsrewing the jet? Like on a 50cc carb or is it more complex? And where can I buy a set of jets? I'm looking at getting #102 but can't seem to find anywhere.
Cheers
they are the same as vfr 400 main jets, search Rick Oliver price list on google, he does a set 0f 4 standard jets any size for £10 or set of 4 dynojet jets for £12
Symon94
Posts: 5
Joined: Sun Feb 10, 2013 3:39 pm
My Bike: Zxr 400

Re: Main jet?

Post by Symon94 »

RedexRobB wrote:Pretty much that yes. Nothing overly complicated. You could try running some redex in the fuel and see if that clears things out a bit. Has it always stuttered or is it something that has happened recently. Has the bike been stood for a while?
It has alway ls done it but bogs more in warm weater and that's what's making me think its running lean. I've tried redex an it helped a bit.
Symon94
Posts: 5
Joined: Sun Feb 10, 2013 3:39 pm
My Bike: Zxr 400

Re: Main jet?

Post by Symon94 »

Symon94 wrote:
RedexRobB wrote:Pretty much that yes. Nothing overly complicated. You could try running some redex in the fuel and see if that clears things out a bit. Has it always stuttered or is it something that has happened recently. Has the bike been stood for a while?
It has alway ls done it but bogs more in warm weater and that's what's making me think its running lean. I've tried redex an it helped a bit.
What's the difference in standard jets, and dyno jets?
ChowderV4
Posts: 98
Joined: Mon Dec 24, 2012 7:57 pm
My Bike: Zxr400L racer

Re: Main jet?

Post by ChowderV4 »

http://www.jetsrus.com/FAQs/FAQ_mikuni_ ... _sizes.htm

Dynojet sizing are slightly different to standard, here's a chart to explain the size equivalents. standard is keihin
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banner001
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My Bike: ZXR400 L4
Location: Nuneaton

Re: Main jet?

Post by banner001 »

does anyone know how the jets from motorcycle products (http://www.motorcycleproducts.co.uk/cat ... 8_423.html) compares to original Keihin jets?

i.e. is a #100 from MP, the same as a #100 from Keihin, i asked motorcycle products, and all they told me was the size of the brass jets...anyone on here know?
UK ZXR400 L3 (1993) - Fully restored and on the roads, my green beast!
JPN ZXR250 A2 (1990) - Revs to 19,200rpm... 'nuff said :smt003
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