78 gs1000 Needle Shimming

[chuck hahn]

Or just drill those out. Heres the chart. maybe jump up 2 or 3 sizes and try that. Then go up from there again if it improves but isnt quite right. Its easier to take a few thousands out than it is to add it back if you go too big too soon.

http://www.jockeyjournal.com/forum/showthread.php?t=64769

[850 Combat]

Or just drill those out. Heres the chart. maybe jump up 2 or 3 sizes and try that. Then go up from there again if it improves but isnt quite right. Its easier to take a few thousands out than it is to add it back if you go too big too soon.

http://www.jockeyjournal.com/forum/s...ad.php?t=64769

Ivey Engines, http://iveyengines.com/Aboutus.htm , built the engine in my Cortina. They couldn't come up with jets for my Delorrtos, so they drilled them. Now I'm not sure what they are. I would prefer real jets with the correct numbers. If they had been Webers, he would have had the jets.

[Caferob]

Or just drill those out. Heres the chart. maybe jump up 2 or 3 sizes and try that. Then go up from there again if it improves but isnt quite right. Its easier to take a few thousands out than it is to add it back if you go too big too soon.

http://www.jockeyjournal.com/forum/s...ad.php?t=64769

This is an interesting idea. I have drill bits but im not too sure the size I need. from your chat it seems "102" is only on the dynojet side so I would start from there. Im interested in the idea because I'll have the 102's sitting around for experimentation.

Im heading over to the local motorcycle shop that had the shims. They said they will check and see if they have some 130 mikuni jets around.

[Caferob]

The local shop had mikuni 127.5's so I grabbed 4. they also have Mikuni 132.5's but I figure that might be too big. If not then atleast I know what to get. They were 6 bucks each, expensive vs the $1.75 on Z1 enterprises site.

Im going to test it today, move the needle clip up a notch to compensate the 102-127.5 mains.

[Caferob]

I put the needle clips second down from the top (as dynojet suggested) and it still had the needle shims in there. Bike idled like **** and when throttled it would bog.
Pulled the needles out and put the clip one up from the bottom. Took the shim washers out. I accidentally dropped one of the clips and the garage floor ate it right up. I took the clip off the crf50 and it worked for now, the local shop has some clips im going to grab today.

Will see how it starts tonight

[TxGSrider]

I might like to suggest that the needles and main jets shouldn't effect your idle. Also, its usually best to just adjust or change one thing at a time and note the effect, otherwise you can spend allot of time chasing your tail.

[OldVet66]

I put the needle clips second down from the top (as dynojet suggested) and it still had the needle shims in there. Bike idled like **** and when throttled it would bog.

I wouldn't pay much attention to information for Dynojet needles when you are using stock needles. It might have a poor idle because your idle jets are too big. You mentioned 20, they should be 15. That doesn't change on these carburetors when jetting for 4-1 pipes and pods, but some people change them anyway.

[Caferob]

UPDATE: The bike started, idled decent after adjusting the idle screw (I bench synced the carbs each time the needles were pulled). The bike really runs strong now but still has carb issues.

While running, the bike began running on two cylinders. I tapped the coils, nothing, I tapped the Martek 440 electronic ignition (the cover is off) and guess what, my Electronic ignition is bad. After tapping it, it would jump from 4-2 and back to 4 cylinders then only run on two again. I pulled the mechanism out and the Martek has a plastic rotor that just got chewed to all hell. So now time to spend the money on the Dyna ignition and take it from there. Im sure the carbs just need some patience and adjustment as Im sure the jets are fine now.

QUESTION: Does the Dyna S Ignition need the Dyna Coils as well or will they run with stock?

I might like to suggest that the needles and main jets shouldn't effect your idle. Also, its usually best to just adjust or change one thing at a time and note the effect, otherwise you can spend allot of time chasing your tail.

Your absolutely right! One thing at a time.

I wouldn't pay much attention to information for Dynojet needles when you are using stock needles. It might have a poor idle because your idle jets are too big. You mentioned 20, they should be 15. That doesn't change on these carburetors when jetting for 4-1 pipes and pods, but some people change them anyway.

I can't remember what my idle jets were at, I'll have to check as I believe they were stock but might be bigger. Maybe the original owner swapped the idle jets and not the mains.

[OldVet66]

Good thing the Martek showed itself now, they don't have that good of a reputation. The Dyna S is pretty reliable and now the modules are tiny compared to the old ones. Should dissipate heat a lot better and be even more reliable. I think the Martek cover was a heat trap.

[Caferob]

Good thing the Martek showed itself now, they don't have that good of a reputation. The Dyna S is pretty reliable and now the modules are tiny compared to the old ones. Should dissipate heat a lot better and be even more reliable. I think the Martek cover was a heat trap.

I read they don't last very long either. It's kind of weird they would use a plastic rotor that would obviously wear down pretty quick due to friction. Im just waiting before I spend the 130 for the Dyna.
Do I need to worry about the specific Ohms it puts out? I read something about 3ohms and 5ohms, making sure I get the 5ohms but I believe that was for the coils and sparkplug cables right?

[Chuck78]

You only use .010" or .020" or so thick washers to move the needle up a half clip position aporoximately. Use the clip notches to roughly tune, if you need slightly more fuel, move up 1 more notch (clip down 1 more moves needle up 1 notch's worth of height) or leave the needle in the 2nd from bottom and shim it up higher with washers all of exact thickness between the 4 carbs.

it will run "really good" by feel of it with it too lean, so you really need to use the recommended baselines and then start doing plug chops. This is really critical. Find a desolate road with a big hill, fairly straight, where you can hold a certain throttle position through a couple of Gears, then hit the kill switch pull in the clutch and close the throttle all simultaneously. Pull over on the side of the road and let the engine cool off for a few minutes, then pull out a spark plug and put in a new one, ride it home. You typically literally have to chop the threads off of the spark plug to get a reading when you are in the very close ballpark range. If the whole entire porcelain insulator is still black, then you are way too rich. You really should probably head out with a brand new or at least clean spark plug in that cylinder, and then ride around for about 10 minutes or so, maybe 15. Wide open throttle Main Jet measuring plug chops can be quite intimidating, as holding the throttle wide open for seven seconds even on my modified 750 ends up with me doing nearly 100 mph... this is why I bought a wideband O2 sensor and air fuel ratio gauge and controller. Much easier, maybe the best $150 I have spent on bike tuning tools ever

When you get very close to being tuned properly, even with the wideband O2 sensor, you need to do a plug chop on all four spark plugs to make sure there are no variances between the cylinders, especially comparing the middle two with the outer two, as they run hotter in the middle and occasionally need 1 size larger mains than the outer pair.

The dyna-s is only really reliable if you have a nearly perfect electrical system. It will fry with 17 volts, and if you get your charging system charging at 13.7-14.2 volts with a used OEM "Polaris 4012941" (search ebay for used OEM, NOT a new replacement, must be the Shindengen SH-775 found by searching 4012941 polaris, new replacement could be Chinese look a like), your coils and dyna s won't likely be seeing anywhere near that ~14v voltage due to old dirty wiring and switches, & inherent old school wiring methods.

you ABSOLUTELY need to do a common coil relay mod to power a dyna and your coils, original or dyna greens. Look into this. I will never install an aftermarket electronic ignition on anything ever again without putting a coil relay mod in place on the bike. I have seen many failed dynas.
all due to bike voltage supply issues. Dyna modules will fry themselves and become intermittent if they aren't seeing 12v or more. You would be very shocked to see how much of a voltage difference there is between the voltage at the battery, and the voltage with the bike running testing it at the ignition coils and Dyna. 10 volts is not uncommon when you figure in old charging system, 9 feet of wire with a bunch of loose and dirty connectors and green dirty corroded wire at connector crimps, a filthy dirty ignition switch with poor riveted on terminal leads that also get loose/dirty/corroded (more of a problem than the switch contacts typically), and a dirty ignition kill switch...
Also go through Jim's aka "posplayr" (GS owner snd aviation electronics engineer) GS Charging System Health posts linked in his signature file. When installing your regulator rectifier, pay attention to hid regulator rectifier grounding method, his single point ground principle, & his chart that shows "popular rewiring for GS's" or something along those lines. Better fusing and power distribution method with a few very simple wiring alterations. You will need to un-tape the harness around the air box and battery area to do this and add a wire or 3 for the coil relay you will be adding. Have soldering iron, DeOxit contact cleaner, and a big assortment of heat shrink tubing handy, as well as some 1/4" female blade terminal wiring connectors, a high quality set of $30 terminal crimpers, dielectric grease tube, & some good 14-16-18g strippers.

If you don't do all of this now, it will come back to haunt you sooner or later. None of this is terribly hard if you take the time to search GSR on how to do it properly

[Chuck78]

Valves are easy to do with the $20 motion pro valve bucket depressor tool. Measuring calipers are handy if the shims were installed with the ink stamped side up (i.e. the size markings will be worn off!). Definitely plan on having a new valve cover gasket on hand, and likely having to spend some time scraping off the thirty-year-old gasket that is stuck to the head and the cover.

If you can spring for the purchase price of four of those new half circle rubber plugs on the end of the head, put those in as well. Make sure the aluminum surfaces are clean, and I often put a very tiny amount of RTV high temperature silicone to hold those in place so that they don't come out the next time you pull the top cover off. Just don't put so much silicone that it squeezes out and glues itself to the new gasket.

[Chuck78]

Do you have any bike porn photos of this beast for us? That is generally mandatory for you to get this kind of help on GSR! There's got to be something in it for the rest of us besides just helping out!

[Chuck78]

Also, you can drill out your jets, but you will need a machinists drill bit set period you will not find this at the hardware store typically. The jet sizes if I recall are only about .003" apart. That tiny amount indeed makes quite a difference. You need to be very careful when drilling them out not to elongate the holes as well. I know some people use a hand drill. The drill chuck needed to hold these tiny bits maybe something that your home drill is not capable of as well. Just buying mikuni jets is much easier.

[Caferob]

Chuck,

The electrical system currently charges between 13.7 and 14.5. I replaced the RR with Duane's upgraded one. Connected the 3 yellow wires, replaced old connectors and added a ground so the charging system is spot on. So I would need the Dyna S ignition and the green coils? Do the coils need to be 3ohm or 5ohm?

The valves are done and the bike screams!

As for the carbs, Im waiting to get the ignition in before messing around with the jets again. I did buy the mikuni jets though.

Pics! I will post some photos and I have created some youtube videos as well.

VIDEOS

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