won't run w/o the choke!! NEwbie!!

[cowzx750r]

A friend gave me a 95 Ninja ZX750R that was sitting in his garage for three years. Before starting, I drained and replaced the gas because there was some rust in it. I bought a new battery, choked it and it started up!! Release the choke and it dies out. Start it again with the choke and it starts right up!! It won't run without the choke and when I try to throttle it, it boggs out and dies! This is my first sportbike. I've mess with a few dirtbikes. I have a manual, I just need some advice. I have removed the carbs and just cleaned the mains,primaries and float bowl. also do they sell individual air filters for this bike? The factory air filter box is a pain!! Can the engine run without all those hoses that go to the air box? sorry, so many questions, I have a feeling, I'm going to be on this forum alot!! Thanks, everyone!!

[snuffy1828]

yes they sell indivisdua air filters for the bike but carb must be rejetted for them as for as the carbs go you need to disable them (rubber pices and diaphram) and get some good carb cleaner and soak all parts except the rubber per directions on can and blow all passages out with air to make sure they are clear then reassemble and install
hope this helps
Mark

[elr658]

Avoid K&N pods like the plague. Really! Don't do it. Do not believe the Dynojet hype. Before that, clean the pilot jets.

[BEANER]

you should just have to clean the carbs real good after you take them apart and spray with carb cleaner you might want to take a piece(just one)of wire from a wire brush and poke it throu any and all holes then hit it with the carb cleaner again and blow all the crap out. as for the hoses i think you need them as well not sure I'm no mechanic but i do fix most of my stuff

[cowzx750r]

I have a friend that have a set of carbs from his 90' ZX7 with stage 3, can I run this with the stock air box or should I get the individual aftermarket ones. What do I do with the hoses that attach to the stock air box if I decide to go aftermarket and who sells them? Thanks all for your advice!!

[QKENUF4U]

ELR just hasnt tuned a bike correctly yet with pods. i have them on my ZRX and will NEVER go back to a stock air box. who ever tuned mine did it PERFECT (anywhere from 115-40*f its perfect) now it will take a bit more tuning but its easy if ya dont have stupid air box to screw around with. i can pull my carbs,rejet, and be back riding in 30-45 mins
as for your problem, clean the pilots, clean/replace the airfilter,put in a in-line fuel filter, make sure the tank is clean of rust etc..put in new plugs,oil/filter and make sure the rest of the bike is road worthy (tires etc.) and get riding.
good luck

[SGVRider]

Diassembling an airbox just to get at the carbs is a genuine pain in the arse, and can take forever. Get the K&N pods if you're going to be messing with the carbs and engine a lot, otherwise just leave it alone if you don't want the hassle of tuning it with the K&N pods. Some bikes run better with them than others, my EX500 will never run right in the low range with the pods, but it's worth it because it's a racebike and I don't have to mess with a POS stock airbox to work on the bike. DO NOT use a piece of wire on the jets, you could inadvertently alter the size of the passages, then it really won't work right. Shoot carb cleaner through them and use compressed air to clean it out. Also, install an inline fuel filter between the tank and the carbs to catch any remaining rust. If the rust in the tanks gets into the carbs it will ruin all of your work, I had the same problem.

Originally Posted by QKENU4U

ELR just hasnt tuned a bike correctly yet with pods. i have them on my ZRX and will NEVER go back to a stock air box. who ever tuned mine did it PERFECT (anywhere from 115-40*f its perfect) now it will take a bit more tuning but its easy if ya dont have stupid air box to screw around with. i can pull my carbs,rejet, and be back riding in 30-45 mins
as for your problem, clean the pilots, clean/replace the airfilter,put in a in-line fuel filter, make sure the tank is clean of rust etc..put in new plugs,oil/filter and make sure the rest of the bike is road worthy (tires etc.) and get riding.
good luck

It depends on the bike, never use the pods on an EX500 unless you have a compelling reason, it's impossible to run it right without the stock airbox.

[elr658]

Try that with a 750F Quick. Won't happen. Now the CV carb found on an HD (Incidentally the SAME one found on a KLR650) IS adaptable to pipes and aftermarket airfilters. I do it all the time. Most amateur tacklebox mechanics have NO IDEA how a CV carb works, therefore I recommend a stock configuration.

[BEANER]

Originally Posted by SGVRider

Diassembling an airbox just to get at the carbs is a genuine pain in the arse, and can take forever. Get the K&N pods if you're going to be messing with the carbs and engine a lot, otherwise just leave it alone if you don't want the hassle of tuning it with the K&N pods. Some bikes run better with them than others, my EX500 will never run right in the low range with the pods, but it's worth it because it's a racebike and I don't have to mess with a POS stock airbox to work on the bike. DO NOT use a piece of wire on the jets, you could inadvertently alter the size of the passages, then it really won't work right. Shoot carb cleaner through them and use compressed air to clean it out. Also, install an inline fuel filter between the tank and the carbs to catch any remaining rust. If the rust in the tanks gets into the carbs it will ruin all of your work, I had the same problem.



It depends on the bike, never use the pods on an EX500 unless you have a compelling reason, it's impossible to run it right without the stock airbox.

As I said I am not a mechanic but I did have a mechanic tell me to do that with the wire sorry for the bad advice

[zedx11]

Originally Posted by elr658

Try that with a 750F Quick. Won't happen. Now the CV carb found on an HD (Incidentally the SAME one found on a KLR650) IS adaptable to pipes and aftermarket airfilters. I do it all the time. Most amateur tacklebox mechanics have NO IDEA how a CV carb works, therefore I recommend a stock configuration.

some of these guys would rather dazzle you with BS and give advise that is over most peoples head than just give the safest overall answer.

[JimmyD]

While I'm sure no one's listening (it always seems the words re-jetting, pod filters, and aftermarket are synonymous with "common sense be damned") the reason your bike isn't idling without choke is because the small idle passages in the carb are blocked up. You're going to need to bath the carb bodies in something, one at a time (seafoam will work) to get them cleaned out.

A parts bath will set you back about 30 bucks at an auto parts store but an old stainless steel bowl will work just as well, so long as you never eat out of it again.

[cowzx750r]

TX, JimmyD !!I'll PU some "Seafoam" and see how that works out! Is there a trick to attaching the stock air box to carbs? Those springs that help seal the boots from the carbs to the airbox always give me problems!! It seems no one sells those individual air filters for my 95 ZX7, I quess I'm stuck w/the stock box!!

[JimmyD]

Well, the important thing is to get the bike working correctly 100% stock. I dunno what the airbox setup looks like on a ZX-7, mine attaches to my carbs with rubber "boots" and band clamps (they resemble a pipe or hose clamp). If I ever needed to I could go to my local hardware store and buy hose clamps that were big enough to fit, I'm sure.

[SGVRider]

Originally Posted by BEANER

As I said I am not a mechanic but I did have a mechanic tell me to do that with the wire sorry for the bad advice

No need to apologize, someone, I believe JimmyD or one of the other guys here told me never to do it after I had the same erroneous thought. A bottle of compressed air works great. CowZX, install an inline fuel filter, if any remaining crap comes downline from the tank you will be removing and cleaning those carbs again. A mechanic told me not to use the automotive carb cleaner as it could damage the finish on the outside of motorcycle carbs and lead to exterior rust, I used it and it didn't seem to do anything negative, but I used the California version of Berryman's that probably isn't as strong as Berryman's sold in other states.

[zedx11]

Originally Posted by BEANER

As I said I am not a mechanic but I did have a mechanic tell me to do that with the wire sorry for the bad advice

I have heard that before too. one thing I think you may have misunderstood was all the holes. he probably told you the holes in the emulsion tube and jets but like was stated, you can change the size of them if the wire is too big. you can get a carb cleaning tool similar to this. this one is more like a acetylene torch head cleaning set because of the abrasiveness of the wires. carb ones are smooth.



here is something that may help others.

Carb Cleaning 101

Warning: Remove all rubber parts before you begin. These parts usually include vacuum diaphragms, needle valves, o’rings, hoses, and other parts. Spray cleaners will damage these parts. Do not disassemble individual carbs from the carb bracket.

Air & Fuel Passageways: Trace and learn individual fuel and air circuits from beginning to end. Machines can only drill straight through the cast passageways. To change direction, another angled passageway must be drilled. The union is plugged with a brass or bronze bead. Inspect and clean each passageway with spray cleaner, brushes/pipe cleaners/etc, and compressed air. Remove any discoloration and debris. Look for spray cleaner to exit from one or more passageways.

Jet Cleaning: Inspect jets by holding to light and look through them. You should see an unobstructed round hole. Clean the jets with one or more of the following: jet cleaning wires, soak solutions, carb spray cleaners and compressed air. Re-inspect jets after cleaning and install when clear of obstructions. Some main jets have paper-like gaskets. Most have metal spacers between the jet and the emulsion tube. Some screw directly into a brass emulsion tube which is machined for a 7mm wrench at its float chamber exposed base.

Inlet Fuel Valve: Inspect the needle valve & spring. Press down the tiny metal rod that protrudes from the butt or float end of the needle valve. The spring should move freely and return the rod to its location. Check the needle valve’s seat area for a groove or other wear. It should appear highly polished. Some needle valve seats are rubber and wear may not be visible. Inspect the needle valve jet seat. You can clean the jet seat with Q-tips and semi-chrome polish if necessary.

Carb Body Castings: Blow air through the atmospheric vent holes located on the dome of each float bowl chamber. Air should exit via hoses or brass nipples. Inspect the emulsion tubes and passageways (cast towers that jets thread into) for discoloration and debris. Clean interior emulsion towers with a soft bristle gun cleaning brush. Clean each Venturi (main carb bore).

Needle Jets & Jet Needles: Clean the needle jets, jet needles, and passageway or tower that needle jet screws into. Clean the emulsion tube (pipe between needle jet and main jet) (Main Jet may screw into emulsion tube). Jet needles are part of the throttle slides. See below.

Throttle Slides: There are several types of throttle slides: Mechanical linkage, vacuum, diaphragm, and cable. Disassembling the jet needle from the slide is not always required for cleaning. If you have vacuum piston type throttle slides (large diameter solid metal slide), avoid cleaning the lubrication from sides and caps. If piston type check cap vents and passageways with air. Clean if necessary and re-lube. If you have rubber vacuum throttle diaphragms, inspect for dry-rot, defects, and tears by gently stretching rubber away from center. Do this until all areas around diaphragm have been inspected. Replace any defective part as described above. Clean carb body areas around diaphragm including air passageways and air jets. Diaphragms have a locator loop or tab fabricated into their sealing edge. Observe this locator upon reassembly. Avoid pinching the diaphragm when reinstalling caps.

Fuel Screws: Fuel screws have sharp tapered ends. Carefully turn one fuel screw in while counting the turns until it seats lightly. Warning: These screws are very easily damaged if over tightened into their seats. Record amount of “turns-in” and remove the fuel screw, spring, washer, and o’ring. The fuel screw is part of the enrichment (choke) circuit…clean passageways as described above. When carbs are assembled, spray low PSI compressed air into diaphragm air vents located at intake side of carbs. Throttle slides should rise, then fall when air is removed. Lightly lube external moving linkages. Reinstall carbs and follow through with carburetor synchronization.

Throttle Cables: Lubricate cables periodically. If cables are disconnected from carbs or removed for replacement, etc . . . remember cable routing and ensure proper reinstallation routing. Avoid bread-tying, sharp bends, and pinching cables. Adjust cables so throttle grip has about 5mm of play or throttle slides or butterfly valves may not open completely (full throttle)(wide full open).

Float Bowls: Inspect float bowls for sediment, gum or varnish, crystallization, and defects. Clean all pipes, tubes, passageways, and embedded jets with cleaners and compressed air. Remove and clean the drain screw and area. Inspect bowl gasket and replace if necessary. Clean and inspect overflow pipes and tubes, look for vertical cracks.

Floats: There are several types of float materials: plastic, brass, black composite, tin, and others. Handle floats carefully. Avoid bending, twisting, denting, or other means of mishandling. Most floats are adjustable by bending a small metal tab near the float axle end. Do not change the float adjuster tab unless tuning fuel service levels. Clean metal floats by soaking or by spraying cleaner and wiping clean. Other material type floats may require replacement if cleaning is necessary. Inspect the needle valve (float valve) and seat. Check needle valve’s spring loaded pin. It should depress and return smoothly and without resistance. Check the needle valve’s tip for a worn groove. Replace needle valve and seat if either symptom exists. These parts wear together and must be replaced as a set.

Choke Plungers: It is common for Mikuni slide carburetors to have indented or hardened choke plunger pads. If the pads are worn, indented or hardened with age, then the idle of your bike will vary wildly as the pads no longer seal well.

Synchronization: This is a fine adjustment performed usually and preferably with the carbs installed and the engine running. The unusual part is performed with gauged wire with the carbs on the work bench. Carburetor synchronizing balances Venturi vacuum at the exhaust side of each carburetor, resulting with smooth idling and optimized performance at all throttle openings. Synchronization is checked using a set of gauges which are either air vacuum type or liquid mercury type. The gauges are connected to vacuum ports on the intake manifolds via nipple tubes or if sealed with screws, sync gauge adapters will be needed. With the engine running at temperature, and with a fan or means of forced convection aimed onto the engine, the carbs fuel screws and idle are adjusted, then the synchronization is adjusted via adjustment screws on the carbs. A reserve fuel tank is recommended for convenience of accessing carbs during this procedure. See gauge instructions and repair manuals for detailed use of synchronization gauges.

Notes: While carbs are apart, record the jet sizes. Look for a very small number imprinted on the body of the jets. Verify that numbers are the same for all jets on models with in-line cylinders. A few transverse-4 models and V-engines, the inner and outer carbs use some different size jets and it’s important to not mix them up. If you have dial or vernier calipers, measure and record float heights. Perform measurements with floats just touching needle valves, though not depressing the needle valve rods. Replace fuel and vacuum hoses. Be sure to use fuel rated hose for fuel. Install or replace in-line fuel filters. It’s a good time to remove and clean interior petcock fuel filters. Inspect carb manifolds for dry-rotting, inspect all clamps and air ducts. Inspect, clean, lube, and/or replace air filter(s).

http://www.riderpage.com/

[cowzx750r]

Now, here's a question..I tore down the carbs and I removed the emulsion tube, flipped the carb over and a small piece fell out. Is this the needle jet? It came from the no.2 carb and I found a similar piece that fell out from the no.4 carb. I checked the two remaining carbs and they don't have these small parts in them. I checked all over to make sure they didn't fall on the ground. Nothing!!? So, is this normal or do all the carbs need this part??

[zedx11]

need a little bit better description than "a small piece". maybe a picture of it.

[cowzx750r]

I think its called a needle jet (16017) in schematic and thats the pic of what I have.

[zedx11]

92063 is the main jet, 13091 is the emulsion tube

I haven't had those carbs apart before but looks like that part goes in over the emulsion tube.

[JimmyD]

Yes. That piece... which I always refer to as the needle jet, have no idea though, is supposed to go into the carb body first, then the emulsion tube, then the main jet, usually.

Be careful which end of the little grey fella you put in first. Sometimes one end is larger than the other. It should stick up in the carb throat about 2-4mm.

And yes, you need one in each carb. The carbs will NOT run correctly without them, probably super rich. You'll need to go to your dealer and order them. THe good news is they won't be more than 5 dollars each. The bad news is you might have to wait 2 weeks to get them shipped in.

Don't even bother with online or ebay. When it comes to carb parts I only use OEM and order them by part # from the dealer so some smuck doesn't mess up my order.