Air Mixture Advice Needed

clint · Post by **clint** » 23 Jan 2013, 23:58

Hello all,

I could do with a bit of advice. Since I bought my CRM I have had one tiny niggle with it. When I'm only on the throttle a little it seems to stutter but goes well when on the throttle more.

I read up all about air mixture settings on this site, on here http://www.kawasakimotorcycle.org/forum ... -have.html and decided the best thing I could try was setting the air mixture to stock then tweak.

Before making any changes I checked where it was, a quarter turn out. I turned it to stock 1 1/4 out from all the way in. It was a million times worse. I found it was best about where it was to start with but never got it perfect, I'm sure it was better before! It has stock jets and a full DEP system so stock jets should be correct?

I've just been in the shed "tinkering" and noticed that where the air filter attaches to the carb there is no jubilee clip it is just the rubber sat on the carb. The seal doesn't seem great I can pull it away from the carb a little and if it was running let air in. It was definitely like this before I cleaned the carb and checked what jets I had etc.

It has done my head in trying to sort it because it runs brilliantly. Starts first or second kick even when frozen and pulls like a train when I give it more throttle.

Do one of you wise fellas think that's my problem? Do they have a jubilee clip there or does it just slot in? Do you reckon I perhaps freed it up when cleaning the carb so made it a little worse? OR am I overlooking something? Is the problem likely to be related to something else totally?

I have been meaning to post about this anyway and can't get a jubilee clip till the weekend because of work so won't be able to try till then. I'm not sure it's the problem either so any comments/advice would be welcome

Regards

Clint

Post by **fishtail** » 24 Jan 2013, 01:55

yeah u need that clip there..

can do alsorts of weirdness with out.

clint · Post by **clint** » 24 Jan 2013, 02:40

I thought as much thanks. Was dreading someone saying "No mate sounds like you're **** is on it's way out it will get worse". I have thought of somewhere I can get one from late tomorrow so will be trying a jubilee clip on it as soon as I get home (with crossed fingers). What sort of clip goes there is it a jubilee clip or one of those sprung shut things that you squeeze?

Post by **fishtail** » 24 Jan 2013, 04:03

its a thin jubilee clip if u can find one that fits.. the honda one is more like a clamp... that fits in the groove and has a screw that pulls it tight

if u wanna a quick bodge to see if it helps ----> try a zip tie

Post by **knackeredMk1** » 24 Jan 2013, 08:31

Get the carb sealed at both sides first. Also check that the air filter is clean and oiled. Then try messing around with the jetting.

As Fishtail says you will have all kinds of problems getting it to run correctly in the current situation.

Post by **Mudfacetony** » 25 Jan 2013, 06:05

knackeredMk1 wrote:Get the carb sealed at both sides first. Also check that the air filter is clean and oiled. Then try messing around with the jetting.

As Fishtail says you will have all kinds of problems getting it to run correctly in the current situation.

There are six reasons for failure, the main reason for something failing is lack of cleaning, inspection and/or lubrication, Second is worn parts, Third is incorrect setting. This is something we use at the business I work in (a global manufacturing organisation) and the first two are the root cause of about 80% of failures.

So clean it and lubricate it, check for wear, bring it back to basic standard condition (I.E. a clean, lubricated bike with no worn or deteriorated parts) and try running it. Then if this does not work ensure all the settings are correct.

clint · Post by **clint** » 27 Jan 2013, 14:55

Sorted. I put a jubilee clip on and the engine note changed. It just sounded better and was revving higher than usual. I set the air mixture screw which was easier to do as it made much more difference when I turned it than it did before. It is set about 3/4 of a turn out so would this indicate I need a new jet?

As I have never checked the 2T pump or power valve & you said "ensure ALL the settings are correct" I decided to take a look and both were miles out. 2T pump way past the mark (too tight cable) and power valve was about 5-7mm below the mark (too loose cable). I set these back to stock and went for a ride.

It's like a brand new bike it has more bottom end grunt, more top end power & even sounds better. I can't believe the last owner was running it like that. I keep finding daft things up and when I tend to them the bike shows it is grateful. Cheers for your help

Post by **fallenmikethebike** » 27 Jan 2013, 16:40

[quote="clint"]Sorted. I put a jubilee clip on and the engine note changed. It just sounded better and was revving higher than usual. I set the air mixture screw which was easier to do as it made much more difference when I turned it than it did before. It is set about 3/4 of a turn out so would this indicate I need a new jet?

As I have never checked the 2T pump or power valve & you said "ensure ALL the settings are correct" I decided to take a look and both were miles out. 2T pump way past the mark (too tight cable) and power valve was about 5-7mm below the mark (too loose cable). I set these back to stock and went for a ride.

It's like a brand new bike it has more bottom end grunt, more top end power & even sounds better. I can't believe the last owner was running it like that. I keep finding daft things up and when I tend to them the bike shows it is grateful. Cheers for your help[/quote

3/4 of a turn sounds like the jet might be on the lean side. Have you tried cleaning the jet? What size jet is in there currently?
Having said that, they all seem a little different and if it's running without issues

Is it starting without any problems?, weak pilot circuit can make bikes harder to start.
Mike

clint · Post by **clint** » 27 Jan 2013, 17:12

Jets are 128 48 and it is running without issues now. It has always started easily. Just been for a good blast and it's twice the bike it was before all across the rev range.

Because it's only 3/4 turn out do you recommend I try a different jet?

Post by **fallenmikethebike** » 27 Jan 2013, 17:17

clint wrote:Jets are 128 48 and it is running without issues now. It has always started easily. Just been for a good blast and it's twice the bike it was before all across the rev range.

Because it's only 3/4 turn out do you recommend I try a different jet?

If your happy with the current set up, and no faults are apparent then just leave it as it is.
Check the plug to make sure nothing sinister is happening, like very lean running.
When you next have the carb off give the pilot jet a good clean, they are notorious for gumming up.
Mike

Post by **knackeredMk1** » 27 Jan 2013, 17:48

If it hasn't had any lean running problems with the air box not connected properly there aren't likely to be any problems now. Would suggest that you have a check of the piston and bore in the near future because the lack of running lean problems maybe because the piston/bore fit is not a tight as it should be...............

clint · Post by **clint** » 27 Jan 2013, 19:39

I will check the spark plug to make sure it's chocolate brown (been quite black previously) and I clean the carbs on my bikes regularly anyway. I will have a look at the barrel & piston next weekend but it should be good it has had a recent top & bottom end rebuild. What would I be looking for when you say not as tight as it should be? I can get a pair off digital callipers of a friend if measuring bore/piston is required. I have been meaning to have a look anyway for peace of mind.

Air Mixture Advice Needed

Air Mixture Advice Needed

Re: Air Mixture Advice Needed

Re: Air Mixture Advice Needed

Re: Air Mixture Advice Needed

Re: Air Mixture Advice Needed

Re: Air Mixture Advice Needed

Re: Air Mixture Advice Needed

Re: Air Mixture Advice Needed

Re: Air Mixture Advice Needed

Re: Air Mixture Advice Needed

Re: Air Mixture Advice Needed

Re: Air Mixture Advice Needed