78 gs1000 Needle Shimming

[Chuck78]

3 ohm coils. And you DEFINITELY need to do the cheap reliable coil relay mod with a standard Bosch automotive relay (go to parts store look for car horn relays etc). Even with the charging system sorted, your critical electrical components are not seeing close enough to full charging system voltage in about 98% of our vintage bikes. Too many loose/dirty connections and dirty switches with dirty loose crimped riveted terminals, and old dirty copper wire strands. Test voltage at coils with bike running and compare to voltage at battery.

[Chuck78]

This is a very good idea, too:




.

[Big T]

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?

Rob,

I know the Dyna modules have changed over time, but, reliable?
Mine's over 30 years old

You don't have to change the coils, the stock ones will work fine

[Chuck78]

On a bike that I take cross-country a couple times a year, I sprung for new Dyna coils instead of 39 year old Japanese coils with integrated spark plug wires that you cannot readily replace. That is a big bonus of aftermarket coils, replaceable wires as opposed to almost 40 year old wires.

Actually, when I spoke with a dynatek tech support person about some failed units, all failed due to low voltage input, they said that the actual pick up modules have not changed for quite some time, just a slightly different appearance externally, and that is all just in the casing.
3 ohm is what you want, not 5

[Chuck78]

The only thing you need to specifically order is the Dyna S that fits the Nippon Denso advancing unit, or the Dyna S for the Kokusan Denso advancing unit. As I stated before, the magnets are a slightly different height. Both brands units will be found on both years of GS1000

[KEITH KRAUSE]

If your 1000 is in otherwise good tune, The 127.5 mains will be too small for best top speed. If expense is the top priority, then realize the bike won't run it's best. The stock jet needle doesn't work nearly as well with K&N pods and a quality pipe as the Dynojet jet needle. The bike generally won't run as smoothly and will have flat spots in the carburetion.
I would try the stock needles with the e-clip in the 5th (bottom) position. You could also try position "4 1/2" by placing a jetting spacer directly on top the e-clip with the e-clip in the same 5th position. Dynojet uses jetting spacers about .022" thick. Maybe you can find some at the hardware store if you need to try a 1/2 position adjustment. The stock needles will need to be in the richest, or nearly the richest position, to provide enough fuel at 1/5 to 3/4 throttle positions. Be sure the 2 nylon spacers are installed in factory order. The thicker spacer (actually called a ring) goes on top the e-clip/or jetting spacer, while the thinner spacer goes under the e-clip. Be sure to remove the 2 vent line tubes so the carbs can breath better with the pod filters.
Don't underestimate the importance of ignition timing and quality spark. Valve clearances too. The carbs may be well out of synch too and it all adds up to poor performance that even perfect jetting won't eliminate. At the very least, do a careful manual synch (bench synch). Also, some people don't realize there's a second tiny hole just forward of the tiny hole that is the fuel passage that's regulated by the pilot fuel screw. If this second hole is blocked by fuel varnish then you'll have nothing but carburetion issues at idle to 1/5 throttle position. It's not easy to see the hole or clean it out.
As for the pilot fuel screws and side air screws, you may want to try adjusting them. A ballpark starting point for the pilot fuel screws is 1 turn out from LIGHTLY seated. Try 1 3/4 out for the side air screws. Adjust the side air screws using the highest rpm method. With the motor at full operating temperature and idling at 900-1,100 rpm, slowly adjust 1 screw at a time and listen for the highest rpm. At highest rpm stop turning that screw and go on to the next carb, repeat.
Look at your spark plugs and see what color they are. Do plug chops at 1/2 throttle position to see how the jet needles are doing and chop off at full throttle to see how the main jets are doing. Just cruising around town at 40 mph and lower speeds will tell you how the pilot circuit is doing.

[KEITH KRAUSE]

Also, as for plug chop testing, just roll off the throttle and shut down. Don't abruptly snap off the throttle because it could cause the cam chain tensioner to back off too much for a moment and the chain could slip. Not likely but you don't want to tempt fate.

[Caferob]

The only thing you need to specifically order is the Dyna S that fits the Nippon Denso advancing unit, or the Dyna S for the Kokusan Denso advancing unit. As I stated before, the magnets are a slightly different height. Both brands units will be found on both years of GS1000

This is what im not sure of. Ive done some searches and dont see which one my bike has. I was about to order the dyna today because im tired of waiting for a "rainy day". Can you elaborate on this or anyone else?

FYI #1 - I have extra shims and parts during this whole process. Shims & jets
FYI #2 - let me know if theres something specific you want to see photo wise and ill snap some and get them uploaded. Forums are kind of a PITA when it comes to uploading in comparison to other avenues of posting photos.

Thanks guys!!

[Caferob]

https://www.amazon.com/gp/product/B000WJH0HU/ref=ox_sc_act_title_1?ie=UTF8&psc=1&smid=A7A7QO7ETFNWF

There's the unit I am about the buy.

[Big T]

That's the one you should buy

[Caferob]

That's the one you should buy

**Bought. Says it should arrive on May 7th(ish). Ill keep you guys posted. Super appreciate the responses, expertise and tips!!

[OldVet66]

I'm not recommending this particular site, but this is what the current DS3-2 looks like out of the factory today. I had a module fail after many years, out of warranty, and this is what they sent me. I can't help but think that these modules have to cool better than the old style: http://motorcyclesolutionsllc.com/su...ds3-2-ds3-2-pu

[Caferob]

Here we go guys. Ive got a bunch new videos up! Take a look.

https://www.youtube.com/watch?v=-zKOwE3JMEs

[chuck hahn]

Other than that little decel pop she sounds sweet. Check under the tank especially if its been off recently for a wire that may have got nicked when reinstalling the tank. Could be where the wire is shorting and causing the fuses to blow. See what fuse blows and check the wire diagram for what all components are on that fuses circuitry too.

[chuck hahn]

Posted before i read the timing ignition thread. Move the Dyna power led to one of the hot wires going to the coils. Problem done. The signal circuit isnt fused for that power draw.