GT750 Questions and Intro

[tz375]

Maybe also time to look at brushes in the starter motor. It should spin the engine pretty fast.

[simmons1]

Maybe also time to look at brushes in the starter motor. It should spin the engine pretty fast.

Thanks for the suggestion.

[simmons1]

Cleaned the carbs last night. Pilots were partially plugged but not bad.

Good news:

The low end is much smoother and will idle near 1000 -1250 very smoothly.

Bad news:

It still stalls same as before.

How sensitive is the Buffalo and or Dyna S to tired batteries?

I ask because I think I found the combination of things that make it stall.

Headlight on, brake light on, turn signal on it stalls almost immediately near idle.

With the headlight off is doesn't stall much even using the brake and turn signal.

With the headlight on it idles until I grab the brake lever, when the idle gets erratic. Click on the turn signal and it stalls quickly.

[tz375]

You got it. The DYNA triple set up does tend to suck juice out of the battery. They are fairly tolerant down to less than 12v, so it's worth checking the voltage on your system at idle and with the lights all on to see what it drops to just before it dies.

[simmons1]

You got it. The DYNA triple set up does tend to suck juice out of the battery. They are fairly tolerant down to less than 12v, so it's worth checking the voltage on your system at idle and with the lights all on to see what it drops to just before it dies.

Thanks!

Wayne said the battery was few years old. I have a new one on the way. I'll test the charging system as well and report back.

Rich

[simmons1]

TZ375

Would you happen to have the instructions for installing the Dyna S you could post of send me? I would like them for my maintenance records.

Noticed something else last night puttering in the garage.

If I turn on the key with the headlight switch off, I get a nice bright neutral light.

If I turn the key on with the headlight switch on, the neutral light and instruments lights are initially kind of dim and flicker slightly before getting bright. I believe the bike had a new main wiring harness installed when the bike was restored back on 2007.

If I turned the key off and on a bunch of times eventually the neutral light would come bright.

[Suzukidave]

Your most likely thinking this already but it sounds like dirty contacts in the system somewhere .. main switch or even the handle bar switch .

[simmons1]

I think it was a dirty main switch. It seems to be fine now that it has been exercised a bunch of times.

I also went for a spin around the neighborhood tonight and it did not stall. The turns signals actually blinked at idle as well.

The difference was that I installed a couple LED tail light bulbs I had laying around from another project. Hard to believe the charging system/wiring is wimpy enough for the taillights to put a big enough electrical load on the system to cause a voltage to drop big enough to bother the Dyna S. But it sure seems like it did. I am hoping the problem is fixed now. Time will tell.

I'll still be installing the new battery when it gets here so that I have a base line on when it was changed.

[Coyote]

For obvious reasons, I always label new batterys with the install date.

[fastcaprinz]

Sounds very similar to my GT125 starting issues thread. Stalling at low revs too. It makes me more inclined to think it is electrical for mine.

Hope your bike is doing better.

[simmons1]

I rode it about 15 miles last night in 90 degree heat with lots of stop and go sitting at lights, and slow traffic to our local Tuesday night gathering.

It ran perfect, no stalls, smooth idle.

I am a very happy camper. I have a few more things to sort out and change that I have been holding off doing pending the stalling issue.

Full speed a head now.

[pull the wire]

That's good news you got everything straightened out. I was having a similar lamp and slow starter issue's with my GT750. It turned out to be the ground strap from the frame to the engine case had around 4 ohms resistance and a 2 volt voltage drop when the starter was activated. Since the engines are essentially rubber mounted to the chassis, having very good engine to chassis grounds are very important. Also the battery case is rubber mounted so that ground cable can cause issues as well. I replaced mine with very fine strand automotive sound system cable. I think it was 4 or 6 gauge cable. Never had a problem since and all the lamps are brighter, starter seems to be on steroids and less than 1 volt voltage drop to my points. I've upgraded to a boyer ignition for my current build. I hope that's an upgrade . I haven't heard it run yet but getting close.

Hope this helps

[simmons1]

Thanks I'll check that as well.