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Discussion Starter #1
I read in a bike mag a few months ago about removing or rerouting vaccum and air hoses. Can anyone tell me which and where they go ? They also noted something about Air-injection valve, and a carb float vent apparatus. However I could not find anything in the repair manual about these. Or are these things only on the Calf. spec model. Only asking because they said the lost alomst 3 lbs. by removing them. Any help would be great. :drool
 

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Discussion Starter #3
Thanks for the info that is awsome. Also do you have any idea how much if any extra power this might give you?
 

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You will also probably have to rejet. That is why I haven't done it yet.
 

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The float bowl venting mod isn't so much of a power mod, but it will let you correctly jet your bike, hopefully using much smaller main jets (assuming everything else remains stock) for better running, crisper response and better mileage. I've done it, and with both a K&N air filter and a full Muzzy's exhaust, I still needed to switch to one size smaller main jets (168/178). most 7R owners swear by it.
 

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Tiamat said:
The float bowl venting mod isn't so much of a power mod, but it will let you correctly jet your bike, hopefully using much smaller main jets (assuming everything else remains stock) for better running, crisper response and better mileage. I've done it, and with both a K&N air filter and a full Muzzy's exhaust, I still needed to switch to one size smaller main jets (168/178). most 7R owners swear by it.
Yup yup...I agree as well.

I run a 165/175 setup with Micron Race FULL system, 4 Deg ignition advancer, K&N filter (It was free from a bud), emmissions scrapped, floatbowl mod, yadda yadda yadda...
 

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Discussion Starter #8
Sounds like alot of work just to be able to dial in your jets better. So if my bike runs great now and I don't have to rejet don't uck with it. Sounds like you guys know your way around a carb alot more than me, so here is a ? for you. I have a '96 7R, my brother has a '99 7R he had it rejetted by the dealer this spring. This is because it has a full Muzzy Ti Exhaust and the thing was a bit of a dog. Our bike are almost the same except for the exhaust and i have a +2 tooth rear sproket, and you could tell mine would pull away easier in all cases. Now that the dealer rejetted it It runs like crap on a real hot days like 90+, also after riding for a wile then stoping it's hard to start like it's flooded. Have any Idea's?
 

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That's just the thing; if you don't remove the air pump bits the bike is IMPOSSIBLE to jet correctly!

taken from Andy's ZX7 site:

Oleg, here is the secret. There is no way to get a 93-01 RAM AIR ZX7 to jet right. Why do you suppose there are a million questions on this? Why does everyone have a problem with this? The answer is Kawasaki's solution to the problem in the first place. First there is something called the clean air injection system. This is the valve that T's into the valve cover that everyone talks about. You can take this off and trash it, or leave it alone, this is "NOT" the source of the flaw. There is however, another valve, that controls the flow of air into the Carb Float bowls. Find this, and remove it. What you want to do is to route a hose from the carb float bowls directly into the airbox. What you want to have happen here is air flowing into the airbox, out through this hose and into the carb float bowls. Use a rubber grommet to get this to seal up good.

You should be able to use the stock pieces to fabricate this hookup.

I'm not even going to try and explain the function of this valve, you will have to take my word for it. What happens is this valve closes off airflow to the carb float bowls under acceleration and on top end, and the end result is it is very hard for gas to come up out of the bowls and thru the main jet. SOOOOOO, Kawasaki puts in these huge main jets, 180,190. Thats a joke. But the fuel flow has such a hard time coming up thru these jets they put these laughable large main jets in.

So, try this. Disconnect this valve and hook it up as described. Then try main jets around 150-160 with your BMC filter. Now that airflow into the airbox is equal to air flow into the float bowls, you can use a more reasonable size mainjet, which also allows you to tune in the needle much easier.

This is the only way to properly jet one of these bikes. On the race bikes they accomplish the same thing by enclosing the entire carb assembly in the airbox, and this is exactly what you will have if you connect your float bowls to the airbox with a straight hose and without that valve. Again, I ain't gonna try to explain that valve, Kawasaki had their reasons, just take it off, and you can use much smaller main jets.

I have made this mod on at least a dozen ZX7s, works every time. I even did it on one bike that the owner was sure his bike was jetted perfect, and couldn't believe the difference.
 

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MN7RRider said:
Sounds like alot of work just to be able to dial in your jets better. So if my bike runs great now and I don't have to rejet don't uck with it. Sounds like you guys know your way around a carb alot more than me, so here is a ? for you. I have a '96 7R, my brother has a '99 7R he had it rejetted by the dealer this spring. This is because it has a full Muzzy Ti Exhaust and the thing was a bit of a dog. Our bike are almost the same except for the exhaust and i have a +2 tooth rear sproket, and you could tell mine would pull away easier in all cases. Now that the dealer rejetted it It runs like crap on a real hot days like 90+, also after riding for a wile then stoping it's hard to start like it's flooded. Have any Idea's?

MN7RRider,

My 1999 does the same thing!! I think the jetting must be too rich, but it only occurs when it is hot out and stuck in traffic for me. I am perplezed on how to fix it.....

Stone
 

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Stonecoldchavez said:
MN7RRider,

My 1999 does the same thing!! I think the jetting must be too rich, but it only occurs when it is hot out and stuck in traffic for me. I am perplezed on how to fix it.....

Stone
Back of the mixture screws by 1/4 turn. Mine did the EXACT same thing. 10 minutes later and YIPPIE !!! I found my "ass dyno" was 1/16 of a turn from a real dyno...


:alky
 

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Discussion Starter #12
ZX7ROU812 said:
Back of the mixture screws by 1/4 turn. Mine did the EXACT same thing. 10 minutes later and YIPPIE !!! I found my "ass dyno" was 1/16 of a turn from a real dyno...


:alky
1/16 of a turn you should start to rent your ass out. just kidding. love the look of the bike now that it's done. One ? what happened to the front air intake screens looks like they are missing. :dunno
 

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Discussion Starter #14
Wouldn't you have to clean out your air box alot more. I know they don't block out alot of stuff what about small rocks or big bugs.
 

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ZX7ROU812 said:
Back of the mixture screws by 1/4 turn. Mine did the EXACT same thing. 10 minutes later and YIPPIE !!! I found my "ass dyno" was 1/16 of a turn from a real dyno...


:alky
Thanks ZX7ROU812.

Is that difficult to do? Can I do it with the carbs on the bike? Where are the mixture screws? If someone could show/tell me where, I will give it a try.

My buddy was telling me it might be the plugs are dirty. I checked them this weekend. They had some deposits on them, but I just cleaned them off. He said that won't be good enough though.

Stone
 

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I hate to bring a four-year old topic up again...... but someone tell/show me where the mixture screws are to adjust them.

Thx,

S.
 

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since your bike is a U.S. destined bike, they are capped. All European bikes and maybe Canadian bikes the air/fuel screws are left open. It is easy enough though, pull the carbs off and drill out the plug. If you are looking at the carbs on a bench, float bowl side up, you will see a round tube, behind the float bowl. It is about the diameter of a pencil. There are aluminum caps in the holes.

There are 2 theories on how to remove them:
1. carefully drill them out with a bit(how I do it. Just use a slow speed on the drill)

2. Use a self tapper-drill the self tapper into the cap, then turn it back out
 

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Thanks. but that is a little more than I feel comfortable in tackling.

I thought it was easier than that to do based on previous posters here.

S.
 

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it sounds much more difficult than it is. But unless you are jetting your bike, there is really no need to play with air/fuel screws (depending on what is done to the bike as it sits now)
 

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My bike has a Stage I jet kit and full Muzzy exhaust. Like others here, it runs rough when it is 90+ degrees out and I am idling in traffic. It wants to constantly stall on me.

In the cold it runs like a beast though.

S.
 
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