Hi all,
been trying to sort out my carbs for a couple of days and cant seem to get it right. Have cleaned, and balanced them, have put sealant around the inlets to seal any air leaks, but i think there is 2 much fuel gettin in. The idle varies sometimes and the there is moisture in the breather pipe on the top of the air filter. The screws on the back of the carbs in the small housing tubes,i think they are the pilot screws, need adjusting, but i'm just not sure how the should be adjusted, all the way in or out or half way. There is a slight grate when idling, but that stops when the clutch is pulled in. If anyone has any advice on how to get them running smoother, it would be much appreciated.
Alex.
			
			
									
									
						H2 carb probs HELP
Moderator: Moderators
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				vodkalex
 - Posts: 26
 - Joined: Fri Aug 29, 2008 9:41 am
 - My Bike: zx7r/ zxr400
 - Location: London, Ladbroke Grove
 
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				lewisdale
 - CBT slow

 - Posts: 734
 - Joined: Mon Oct 06, 2008 5:41 pm
 - My Bike: zxr400 H2
 - Location: essex
 
Re: H2 carb probs HELP
hi the slight grate is a noisey clutch, which i have come to learn is normal, im not to sure about the screws though, robb set mine up for me
			
			
									
									
						- 
				vodkalex
 - Posts: 26
 - Joined: Fri Aug 29, 2008 9:41 am
 - My Bike: zx7r/ zxr400
 - Location: London, Ladbroke Grove
 
Re: H2 carb probs HELP
Cheers mate. I think they are pilot screws, but just not sure about how far in/out they should be. mmm
			
			
									
									
						- markzxr400l3
 - Posts: 106
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 - My Bike: ZXR400H2 GSXR750
 - Location: North Wales
 
Re: H2 carb probs HELP
I believe the pilot mixture screws should be 2 and a half turns out from fully in as standard, there is a manual on the main site and its in the spec sheet under the fuel section. I read 'back of carbs' as 'bottom of carbs'.
Make sure you are balancing the carbs with the engine warm and blip the throttle between adjustments.
Mine gets moisture in the pipe but this is normal(ish) I think. This pipe comes from the crankcase and just vents off any moisture in the bottom end. Open to advice on this one but I'm sure thats what its there for, and no big issue as long as its moisture and not dripping wet.
A variable idle is normally symptomatic of a too lean mixture or an air leak. Old trick, get some wd40/easystart/deodorant etc etc (any aerosol that burns) and spray around the inlet rubbers. If the revs rise you have an air leak.
Incidentally I have a varaible idle but this due to a highly dicky wiring loom so ignition circuit is a bit dodgy when warm. i.e. not always carbs (99 times out of a hundred though) Hope this is helpful.
			
			
									
									
						Make sure you are balancing the carbs with the engine warm and blip the throttle between adjustments.
Mine gets moisture in the pipe but this is normal(ish) I think. This pipe comes from the crankcase and just vents off any moisture in the bottom end. Open to advice on this one but I'm sure thats what its there for, and no big issue as long as its moisture and not dripping wet.
A variable idle is normally symptomatic of a too lean mixture or an air leak. Old trick, get some wd40/easystart/deodorant etc etc (any aerosol that burns) and spray around the inlet rubbers. If the revs rise you have an air leak.
Incidentally I have a varaible idle but this due to a highly dicky wiring loom so ignition circuit is a bit dodgy when warm. i.e. not always carbs (99 times out of a hundred though) Hope this is helpful.
- 
				vodkalex
 - Posts: 26
 - Joined: Fri Aug 29, 2008 9:41 am
 - My Bike: zx7r/ zxr400
 - Location: London, Ladbroke Grove
 
Re: H2 carb probs HELP
Cheers for that Mark, will get on that first thing in the mornin!
			
			
									
									
						- 
				zimm
 - zxr400 oc member

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 - My Bike: ZXR400-M4, ZX4, ZX6R.
 - Location: Herefordshire
 
Re: H2 carb probs HELP
what Mark said, + the breather is just to vent crankcase pressure, if theres a significant amount of moisture it could well be symptomatic of a blown headgasket. Which could also explain some of the poor running.
simple test ? taste it, if its sweet its antifreeze.. and you have a blown headgasket.
			
			
									
									
						simple test ? taste it, if its sweet its antifreeze.. and you have a blown headgasket.
- 
				vodkalex
 - Posts: 26
 - Joined: Fri Aug 29, 2008 9:41 am
 - My Bike: zx7r/ zxr400
 - Location: London, Ladbroke Grove
 
Re: H2 carb probs HELP
Hey Zimm, hope your well. Have just changed the headgasket, so dont think its that, well hope it isnt, gonna have a play around today, If it stops bloody rainin!
			
			
									
									
						- 
				vodkalex
 - Posts: 26
 - Joined: Fri Aug 29, 2008 9:41 am
 - My Bike: zx7r/ zxr400
 - Location: London, Ladbroke Grove
 
Re: H2 carb probs HELP
Right, been tinkering in the rain (ooh er!) did the screws 2 1/4 turns, bike seems to rev very smooth now, but does not idle high enough and keeps cutting out. Idle screw is all the way up, any ideas? If i try and adjust the throttle cable on the housings it just makes the throttle sticky. Never ending.