79 GS750 wiring no battery

[switchback_bomber]

Would you mind posting a photo of your upper triple tree? My eyes just don't know what to make of what I'm seeing. To me it looks upside down and cut.

It's right side up, but I ground it back so my gauges fit nicely

[gsrick]

It's right side up, but I ground it back so my gauges fit nicely

Thanks, that saved me a trip to the optometrist. I've seen stranger things.

[switchback_bomber]

got the tank finished up today! the marathon isn't over but I can see the finish line. got the dyna ds3-2 in the mail today, xps is on its way. I think I'm going with another set of shinko tour masters, I looked at the date on the tires and they're from 2007... a little past the best by date. I tried finding the Bridgestone Battlax BT45's but I couldn't find any that fit (100/90-19 &130/90-18).

[switchback_bomber]

Thanks, that saved me a trip to the optometrist. I've seen stranger things.

me too thats a good show

(post bad joke drumbeat)heres a top view of the triple tree

[Chuck78]

, I looked at the date on the tires and they're from 2007... a little past the best by date. I tried finding the Bridgestone Battlax BT45's but I couldn't find any that fit (100/90-19 &130/90-18).

Dude... A 130 is way too big for that, I run a 130/80-18 battlax bt45v on a 3.5 inch rim. You have a stock 2.15 inch rim. Mine fits AWESOME, your rim would be an absurd mismatch for that large of a tire. It would physically mount onto it, but it it would be counterintuitive as it would handle terribly, add excess weight to rob horsepower from your bike, and you would not get to utilize a large portion of the tread near the edge because it is wrapped too much to fit onto a skinny rim.

The best fit on that bike would be an Avon AM26 RoadRider 90/90-19 front & 110/90-18 rear, and you would actually get to use almost the entire tread if you really lean it hard in the corners. You would have a greater contact patch with the skinniest tire because of your rim size.
Avon's run a bit large, by the way.

Next best would be Bridgestone Battlax BT45V in a 100/90-19 front, and 110/90-18 rear. A 120/90 could be fit onto the rear if you insist on a fatter tire, I have ridden this on several bikes that I have built, and it handles well. The 110 is going to give you the best steering response and most crisp handling feel, and not cost you any extra horsepower due to the extra rotational weight, not to mention extra unsprung weight for the suspension.

When I say I have ridden a 120 on several bikes, I am referring to not a battlax but a Shinko 230. They grip extremely well and are very well-constructed, but the rears always end up wearing flat if you do a lot of straight road city and highway riding. I ride very aggressively and can barely get 4000 miles out of a rear end that is very very clapped-out at 4,000 miles even (as in very questionable to ride on a rain covered road due to being down into the tread wear indicators and almost bald). 3200 miles and they are looking pretty darn worn, 3800 and it is time to change, but I ride fairly aggressively (understatement). Others have reported 5,000 miles out of the rears.
If I had a set of tires that have that good of tread on them and were 11 years old, knowing the quality of tire that Shinko puts out, I would consider riding them for the time being at least to get the bugs worked out of the bike. Then depending on what kind of feedback you get, replace them later.

[Chuck78]

You also could look into a Continental Classic Attack radial. Those are pricey! But they are radials that fit our bikes!
The Avon is going to give you the best treadwear, and fairly decent grip, a lot of people swear by then, but I prefer the battle axe as they are a little bit sticky here and have a dual compound rear so the rear still stays fairly rounded and does not wear flat across the center from City and highway riding. The Shinko and Pirelli sport demon drip amazingly, but will definitely wear flat across the top of the back tire as they are very soft sticky Ultra grippy rubber. And they are not a dual compound like the Continental or the Bridgestone. The Avon is just a bit harder rubber, not a dual compound, but it wears significantly better, 8,000 miles out of the rear is no problem at all. Many people swear by these and say they grip awesome, but I have had not quite the same experiences but I also ride a bit more on the aggressive side than most.
If you plan on really piling on the miles for some long hauls on that skinny no cushion having seat, you would probably want to go with the Avon roadrider.
I go for the better middle-of-the-road choice with really good grip in the Battlax BT45R (BT45V) and decent rear tire wear.

I hadn't noticed the picture of your bike, but yours has definitely been hacked up into a hipster Cafe Racer build. The back of the frame is very much chopped off. I have saved some frame pieces from parts bikes that I scrapped just for that sort of occasion, to restore a bike back to having a full seat and good-looking factory tail section with a bit of welding work.

[850 Combat]

I agree on the tire size comments, and the tires themselves. BT45s have really nice traction and feel. Keeping as close as possible to the standard sizes will make the handling more neutral in a turn. Get too big of a tire on the back, and you will have to hold a little opposite lock on the bars to keep it on line. Even one size over width makes a difference.

[switchback_bomber]

well that's good to know, I'm not super versed on tire sizes, and don't even know the wheel width. I think I'll take your suggestion on keeping the shinko's a bit longer, but i'll definitely add your suggestions to the list!

[switchback_bomber]

So I recieved the dyna s3-2 ignition, sh775, and the antigravity xps, and got everything wired up. Tested the lights and they all work as they should, but I am having trouble with the ignition. I started out trying to get the ignition timed up using the light in-line, with no success. I called dyna and they suggested that I pull a spark plug and time it using the spark, initially it was working, strong bright spark, down the line the spark got dimmer, and finally dissipated completely, but she's still giving me spark when I turn the power off. I believe I'm going to need a new unit, because I really don't see anything that would be at fault. the bike is still not running so too much voltage from a bad regulator I can't imagine would cause this, I tested the coils and spark plug wires again and they are fine, the battery is fully juiced up, and the lights all work as they should. here are some things I'm am curious about if they could be an issue.

none of my switched are grounded (ignition, brights, brakes, and running lights) could this be a problem?

Does this sound like just a bad ground in general?

should I have a smaller fuse to the ignition? currently i'm using a 10A

I am using a single point ground underneath the seat where I have the r/r, would not having a wire going from the engine block to the single point cause any issues?

I attached a picture of how I have the bike right now, no more, no less. Thanks for all your guys help

[Chuck78]

I'm at on lunch at work, not much time to fully read, but you cannot leave the ignition switch on for very long without the engine NOT running on a dyna, or else you will fry one of the Dyna modules. This is particularly if the sensor is lined up and trying to fire one of the cylinders.

Also, with a lithium iron phosphate battery, you absolutely cannot drain them down below about 9 volts, below 7 or 8 and they may be permanently damaged.

[Chuck78]

You might want to check and make sure that you don't have your coil black & white trigger wires or the Dyna black and white wires crossed.
Or the exact same symptoms could also come from having the magnet on the rotor timed 180 degrees out (read the instructions, double check).
Very common mistake, I've done more than once in 10 years of playing with Dyna's. I do recall the only thing that I could really get out of it one time when we had it backwards was a gigantic cannon like backfire out the Vance & Hines pipe.

Also, make darn sure you have good fuel flow, clean pilot jets ( has there been ethanol gasoline sitting in the carburetors for many weeks since you have cleaned them and rebuilt them? This stuff is absolute garbage and will follow up your carbs in short order.)

If you have an inline fuel filter, especially the paper element kind, make sure to pool the fuel line off of the carburetors and turn the petcock on to the prime position, which is forward pointing on the handle part of the lever, and make sure you get a good stream of gas out. And make sure no gas is ever coming out of the vacuum line connection!
Do you have good fresh gasoline in the tank?

Did the bike run before with the old ignition, just not well?

[Chuck78]

Also, make sure you have a darn good engine ground strap, heavy gauge wire, from the engine case bolts up to the single point ground. Test and make sure you have a good 12.7 volts or whatever at your ignition coils.

DID YOU ADD A RELAY TO POWER THE COILS AND DYNA-S????? This is CRITICAL, I have literally a pile of bad Dyna S ignitions that got fried from not having enough voltage (11.7v MINIMUM, measured AT Dyna red wire & coils power wires) due tp 12 feet of old wire, a dozen dirty loose old wire connectors, and dirty/loose/worn out ignition and kill switches. I clean all of those very well and check the riveted terminal connections on the ign/kill switches, but I STILL add a direct relay powered feed straiggt from a 10a fuse and battery. Use old Orange ignition coil wire to trigger the relay, add a new ground on the other side of tge relay switching coil.
You can even buy a plastic harness pigtail plug at the auto parts stores that plugs straight into the standard automotive 12v relays. You only need a normally open single pole Bosch style relay. 4 terminals. Common= Line power in, NO = load power out, other 2 are ground and switching trigger power in, & are not polarity sensitive.

Once you make sure you have the wires phased correctly and the rotor positioned correctly and not 180 out, try to start it with the Dyna aluminum backing plate rotated almost all the way clockwise, with just maybe 2mm of gap showing to the left of the screws that hold the Dyna to the engine case. That is generally about where they all end up at. But you definitely need to time it, and you should try and at least find a used inductive pickup timing gun on Craigslist or something.

[Chuck78]

The 30 amp fuse should be a 20 amp fuse, and it should be before the ignition switch, possibly in between the regulator rectifier and the battery I believe is where it should be. Refer to Jim AKA posplayr's posts in his signature file. Find any post by him, and look at his signature file, you will find many very helpful electrical links.

You also may want to take the air cleaners off and spray a little starting fluid in each of the carbs and then try and fire it. Even if it just backfires, you know you have spark somewhere then. That may definitely indicate that you are 180 degrees out approximately if that happened

[switchback_bomber]

I attached a new diagram below, Lmk if this is looking like an A+

you're the man chuck! I spent about an hour on the phone with a guy from dyna yesterday, I mentioned to him that I was wiring the thing from scratch, but I don't think he quite got it. I got the wiring and the rotor position figured out, and I got spark yesterday when it was supposed to spark, but not long enough to get it timed. I'm still not sure exactly what the problem was/is since I left out a couple things, but I'm almost certain the thing is fried.

The bike wasn't running when I got it, the carbs were off and mostly disassembled, the wiring harness was off and demo'd, no battery, and no lighting.

I got the carbs cleaned, rebuilt, and on for the first time in god knows how many years, but I was working on the timing before I was going to fire the thing up (although it sounds like timing it while the bike is actually running is the better way to do). Also noticed the carbs were hard to fit onto the boot, so I think since the carbs were left off, the boots have shrunk and no longer fit very well.

[switchback_bomber]

Is this the right relay to use? https://www.ebay.com/itm/GENUINE-BOS...itleDesc=0%7C0