74 GT380 no start. Need help.

[Rickybigblock]

Vintageman,

I did set the timing with a dial touch gauge before all this junk, it was 2.40mm all cylinders. (380 is the same for all three). I would see what TDC was on my guage, (highest number achieved) then subtract 2.40mm from that number. Save that number in my head. I would then bring the piston back to TDC, reverse the piston (lower) about 6mm, contactamy multimeter to the respective wire coming off the points (white, white w/tracer, and black) and the ground of the meter to ground. I would then slowly raise the piston (really slow) until I got close to the number i remebered from earlier, and wait for the multimeter to read open, note the number on the dial gauge, and adjust the points from there. (With ignition on/run switch on. Is this the right procedure? I would of coarse have to do this all over because i removed the cover again to double check the alignment of the breaker cam gear.

[Vintageman]

Sounds like you did this OK. But are you sure the points you were adjusting was indeed for the cylinder you were measuring? You said

window say "L" and the right cylinder points are opening/breaking?

The only way you could be that much off is if that gear was misaligned?

Are the coil wires crossed maybe?

If your engine is mechanically OK, You are getting fuel, and good spark at the right time the old girl should run.

Start by proofing to you self which it is not and you will find what it is. Timing should be the first thing to be 100% sure OK

[Rickybigblock]

Thank you Vintageman. I need to spend at least a whole day on this thing. Life keeps on getting in the way, but this nice weather has me in over drive. I currently bought new points w/ condensers, plug caps, and ignition coils. I plan on replacing them, and retiming. I'll let you know. About to throw this bike in the back of the truck, and head up there to NH.

[tz375]

....., and wait for the multimeter to read open, note the number on the dial gauge, and adjust the points from there. (With ignition on/run switch on. ...

Are you sure that the pints were just opening at that point? It has been a long time since I timed a points ignition but I am sure that with power on, it goes to zero when the points close. I could have that back to front of course, but when you fit and gap your new points, please confirm that they are just cracking OPEN at the right time. I am sure I used to disconnect the points and then measure resistance or use an old radio and listen to the crack as they open with 12v applied.

[Rickybigblock]

Tz,
I could have been using the wrong terminology in my description. Or i could have been dead wrong the whole time. I've heard about guys making their own testers, and i would love to learn how. Also If you had a process that you could explain in full that would be great to hear. I was just winging it, with how i understood the system, but im not afraid to say that im new to old points.

[tz375]

According to Dan's http://www.dansmc.com/bat_coil_ign.htm" onclick="window.open(this.href);return false;" onclick="window.open(this.href);return false;

The light goes ON was the points open if the ignition is ON.

Back in the bad old days we would use a piece of cigarette paper between the points and slowly turn the motor forward until the paper starts to pull out of the points. IIRC it was about 1.5 thou thick

Another trick used to be with what was known as a transistor radio - ie any radio that you can set between stations and physically close to the bike. When the points opened you could hear the crack from the radio which picked up the electrical waves/EMF or whatever it's called.

Digital voltmeters are a bit problematic. I am told that with their internal batteries and other stuff, they are not as good for determining the actual point of opening. Use an old analog type with a needle and watch the needle swing as the points open.

[Rickybigblock]

TZ,
Thanks for your help once more. I'll give those try. I think i have an old one my pops use to have, see if i can find it.

[Vintageman]

With points closed just take an object and manually open points to see what reading means what.

If you put power on and open quickly you should see the spark plug spark, just to prove you are looking at right cylinder

Yes life + work gets in the way. I have two project in the garage now, little time or I am constantly waiting for a part to arrive. Shipping time sucks.

You will get it going and it will be worth it!

[tz375]

Both good ideas vintageman

[yeadon_m]

Talking of noises, I use Mike's Ear method, believe it or not!

I set up the first cylinder with the dial gauge in and show by inspection that the gauge will rotate several mm BTDC without topping out or falling off the bottom. I use a 0-5mm gauge for the 380 and a 0-10mmm gauge for the bigger triples.

I watch to see that the points open and then the gauge rotates a bit before reversing, so I know I have a 'before TDC' set up more or less.

Set the max points opening gaps first. Then timing. Rotate the motor in your favourite manner which removes slack from the points cam drive system and watch until the pointer is approaching but not yet at the points opening point. Only then turn on the ignition. Note, I removed all plugs and rest the plugs in their caps on the head. I watch the gauge and slowly turn the motor. When the points open, there is an easily audible click of the spark in the plug. Note where on the gauge that happened. Turn ign off to save battery. Continue to rotate motor, counting the distance. If its the right number of mm BTDC, you're done and onto the next cylinder. If not, adjust the points to open earlier or later and go round again. I'm happy within 0.2mm, which is easily done and no more accuracy is needed on these lazy, tolerant motors. I've had many run nicely when they're several mm timing out!

Cheers,
Mike

[Rickybigblock]

Well now I know it's been a LONG while now but finally got the timing tuned in with the help of someone more saltier than I. So now it lives again! After replacing the plugs twice, since the bike was loaded and had a case of black lung. Runs okay still needs to be cleared out, but currently having a problem with the clutch. Seems to be dragging. I'm going to be replacing it. Has anyone ever tried adjusting the clutch by turning the adjuster rod (under LH case cover) in until it bottoms out, then backing it out one quarter turn? When I tried it didn't seem to bottom out. Is it a solid bottom, or should I be feeling for something? Anyways that's one of my new issues I'm facing. I'm still waiting for all the residue crud to vacant my exhaust from the previous unknown years of sitting. Also while on a test ride, I was having difficulty shifting up, the shifter would not "click" up, it would go down easy, but sometimes while shifting up remained stiff. Could this be linked to my clutch problem or is this a fork and drum issue? Thanks again two stroke community.

[yeadon_m]

It may well relate to the clutch not fully disengaging as you try to shift. You should feel the adjuster bolt (the one facing outwards and with a slot) 'bottom' quite clearly, though if you heave on the screwdriver you can start to compress the clutch springs. The aim of all the adjustments on the cable (handlebar end, clutch actuator end at the case, cable inside the case) is to have the clutch cable slightly slack with the lever is released, but begin to disengage the clutch as soon as cable free play is removed when you start to pull the lever.
If it still won't fully disengage, it may be that there are clutch plates sticking together. If the action is heavy at the lever, the cable might need changing, the ramp inside the cover might need cleaning or its mounting screws are loose, or the pushrods (2 off) might be bent, or the 'fingers' in the clutch outer basket may have worn grooves in it and can be improved by careful filing. Its most unlikely that, beyond this, the clutch is at fault. The are very tough. I supposed you might have a bent metal clutch plate or a broken fibre clutch plate, though I've never seen either.
Good luck!
Mike

[Alan H]

Doing timing you should never turn the engine backwards, only in the direction it rotates.
It can put timing out due to backlash in the gears inside, and also break the nylon gear driving the points cam.

[jabcb]

Suzuki recommended that timing on the GT380 be set by turning the rear wheel with the bike in 6th gear. As Alan said, you should turn the wheel in the direction of normal rotation.
You could alternatively use the kick starter.

http://www.ozebook.com/compendium/techb ... 0mc119.pdf

[yeadon_m]

I don't think it matters if you rotate the engine in its running direction or the other way, so longer you use the drive train to tun it (rear wheel while in gear, or kickstarter).
The absolute no-no is to heave on the 14mm AF nut holding the points cam on. That will ask the plastic points cam gear to turn the motor over and as it isn't very strong, it is very likely to break as you heave. Just don't risk it! I've had one break while riding, and its 'very annoying'. Its one of the very few single parts failure that stops a GT triple dead. I can't think of a similar single-point vulnerability on the 550 or 750 or indeed any other on the 380, of a nature where there is nothing you can possibly do by way of a roadside fix. If ever someone tours on a 380 - unlikely I know, though I did this in 1981, 5000miles around Europe! - please bring a spare plastic gear!
Mike