Bought my first 2 stroke - started for a bit & now doesnt :(

[Alan H]

GT550 J/K/L B7ES. M/A/B B8ES. These are the long reach type.
For initial startup, I used B6ES as mine was 'full' of oil. Do not ride the bike with these in!
I over oiled every bearing and rubbing surface during rebuild and just put an eggcup of oil in a couple of pints of petrol. I used 'super' fuel, and always use this as it runs a bit better - less ethanol in it. It still needed a couple of squirts of easy start initially, but after the smoke cloud cleared, starts & ran fine.
Not sure the oil/petrol mix really did anything as the 550 engine (and other Suzy triples) has crank throwers to get oil away from the bearings, which is why we should never buy a bike with the oil pump removed.

[bpapachr]

Good to know about the oil pump Alan.

I changed the plugs to the longer ones and the bike fired right up. The bike idles well and I checked for vacuum leaks and the only thing I'm thinking it can be is to replace or make the boots that deteriorate just below the throttle valve adjustment nut. The run away revving doesn't happen anymore which is a huge relief.

The only tough part I'm having trouble understanding now is that I took it for a ride around the block, maybe 15 minutes or so and it progressively got worse and worse, sounded like it has asthma. I have no clue whether that's rich or lean? Gonna pull the plugs tomorrow and see. I dont know how else to best describe it but it loses power and when you pull the throttle the bike goes nowhere and just sounds like its gasping. The first video I posted where I say "for your viewing pleasure.." is the best one that really shows the way it sounds after riding for a brief time.

I'll be digging into the motor this week at some point, I'm waiting for the gaskets to come in because I have a massive oil leak that seems like its coming from the transmission, just behind/underneath where the filler plug is. I'm assuming its common. I hope these gaskets are good replacements. Whats a good liquid gasket to use for the crank halves for when I put them back together? does anyone have types that they like better than others? I'm not 100% sure but this could be where some oil may be leaking as well.

My last question of this evening, or morning is about timing...This is my set up and I was using Coyotes very well done diagram in a previous post.

The one part, well two, I don't understand 1. to find the highest point on the crank you eyeball it? 2. after the left set has been gapped. You crank the 14mm around to line up the lines on the crank case and housing with the "L". The test light turns on way before the markings line up. Since it doesn't have another two screws the move the plate (or the "B" screws), how do you adjust the left set to open at the right time? If you remove the same screw you gapped it with, it would defeat the purpose of gapping it. I am most likely over thinking this...

Thanks guys! Today was a beautiful riding day in the north east, hope some of you got out there and enjoyed it.

[Coyote]

To adjust the timing for the left, loosen the 3 screws that retain the plate. One at 10 o'clock, one at 2 o'clock and one behind the blue (repaired) connector. The slots at the 7 o'clock position are for rotating the plate. Something looks way out of whack here The left hand points (extreme right) appear to be open with the cam on a low area. The single screw right above those contacts is for setting the gap with the cam at it's highest position. Yes you eyeball it All 3 gaps should be set before you start to time it You start with the left set (extreme right) and rotate the back plate to set the points to open on the 'L' mark The plate does not get moved again. The you set the center and right The center and right points have 3 screws each. One is for setting the gap abd the other 2 with slots are for setting the timing.
I have a super sensitive test indicator from my job. I thought about offering a service to mark the highest point on the cam with a small notch,That would remove the eyeball guesswork. All I need is a shaft turned to slip fit the cam on. The service would be $5 + shipping both ways.

[bpapachr]

Thanks Coyote, will let you know if I have issues getting it timed right. How can you tell its on a low point? Because the right cylinder point looks open as well?

[Alan H]

Remember to set the gap of the points you are doing before lining the marks up. The points will be fully open (and that's when the gap is set) AFTER the marks have lined up, and it's best to only turn the engine forwards so any backlash in gears etc doesn't affect the timing. The 550 cam is on an extension of the crank so not so important, but tbe 380 and 750 have a gear which can have a bit of backlash. Only turning the engine forwards is good practice anyway.
Looking at your points plate, personally I would remove the 2 felt pads that touch the centre cam, clean tbem with thinners or carb cleaner and then put a couple of drops (NOT SOAKED!), spray wd40 or similar over the points plate then wipe clean and then replace the pads so they just touch the cam. If the pads are over oiled, you end up with crap all over the place - something like it is now!
As has been previously said, you do the 'fixed' points first - that's the ones on the right of the plate and turn the complete back plate to line up the marks, then move to the next set . Do the gap first, then move those individual points without altering the gap. Tgere are some small 'tits' that you can put a screwdriver on to move the points with their locating screws slightly loosened.
The points gap gives delay (or detente) that allows the capacitor to charge, so a wrong (small) gap may not allow a full charge and give a poor spark and too large a gap might not allow the points to close, so won't fire at all.

You didn't expect all this to be easy did you? If it was, everyone would do it!!!

[Suzukidave]

Its kinda hard to tell from the points plate picture posted , but it looks like the points rubbing blocks are worn down from no lube on the points cam . If they are too worn it may be difficult to set the gap and still get the timing to line up .

[Glyn.G]

Hi, Not to be picky but I don't like the route your wires to the points are taking, it looks as though 1 or maybe 2 of the wires are in contact ( rubbing ) on the points. Could stop the points working correctly if they are. I would re-route them round the outside of the back plate.

[Coyote]

Worn points can develop little peaks on them, not allowing them to close properly. That could be what I am seeing

[bpapachr]

Remember to set the gap of the points you are doing before lining the marks up. The points will be fully open (and that's when the gap is set) AFTER the marks have lined up, and it's best to only turn the engine forwards so any backlash in gears etc doesn't affect the timing. The 550 cam is on an extension of the crank so not so important, but tbe 380 and 750 have a gear which can have a bit of backlash. Only turning the engine forwards is good practice anyway.
Looking at your points plate, personally I would remove the 2 felt pads that touch the centre cam, clean tbem with thinners or carb cleaner and then put a couple of drops (NOT SOAKED!), spray wd40 or similar over the points plate then wipe clean and then replace the pads so they just touch the cam. If the pads are over oiled, you end up with crap all over the place - something like it is now!
As has been previously said, you do the 'fixed' points first - that's the ones on the right of the plate and turn the complete back plate to line up the marks, then move to the next set . Do the gap first, then move those individual points without altering the gap. Tgere are some small 'tits' that you can put a screwdriver on to move the points with their locating screws slightly loosened.
The points gap gives delay (or detente) that allows the capacitor to charge, so a wrong (small) gap may not allow a full charge and give a poor spark and too large a gap might not allow the points to close, so won't fire at all.

You didn't expect all this to be easy did you? If it was, everyone would do it!!!

Great tips! thanks. When I remove the felt tips, should I just spray it on the felt tips or soak them for some time to get all the oil out? Also, I tried moving the entire plate to line up the points and the light never turned on...So I'm not sure where that leads me? I moved the plate in either direction and I gapped it before as you all mentioned and the "L" is lined up I turn the plate and it maxes out on both ends and the test light doesn't turn on...Lastly, I'm usually pretty good with tits, not sure which ones your referring to though? I'm gonna use a flat head screw driver to slide between the points and as I turn the crank, will let it slide down until its for sure the highest point. Then check the gap and follow the rest of the advice.

And most importantly for reminding me that I'm working on a 40 year old bike!

[bpapachr]

Hi, Not to be picky but I don't like the route your wires to the points are taking, it looks as though 1 or maybe 2 of the wires are in contact ( rubbing ) on the points. Could stop the points working correctly if they are. I would re-route them round the outside of the back plate.

This is great, thanks. I had a feeling this could be a problem and I'm glad you posted this. I'm going to re-wire these and make sure the wires don't touch any of the points.

The one wire that PO spliced with the blue connector and ran down the middle seems like the only one out of place? the others seem to be in a "stock-ish" position but I feel like they should be looped the opposite way, going up and around, contouring the housing.

[bpapachr]

Worn points can develop little peaks on them, not allowing them to close properly. That could be what I am seeing

It seems like they are not doing their job as well as their supposed too...I also noticed that when I've looked up the breaker points for my bike, Two are "V" shaped and one is flat. On my bike currently, it has two flat ones (left and right) and the center is the only "V" shaped one.

This is the auction I was looking at...
http://www.ebay.com/itm/1972-1977-suzuk ... f3&vxp=mtr

Is this not the right one?

[bpapachr]

So I'm in the process of taking apart the motor because I cant seem to figure out the issues with the bike losing power after it heats up. I put the new plugs in, worked fine for a bit and then started to S*** the bed again. Some fun this were found like the starter motor which wouldn't rotate at all


Not sure what to think about the cylinders except for the left one. The pictures below show some sort of wear deep scratches and grooves by the pin. I never torn this far into a motor before but I'm assuming this isn't good. Hopefully one of can help with the severity of the damage? Am I looking at new piston rings or am I re-boring and putting in new over sized pistons in?


Left Cylinder





Center Cylinder


Right Cylinder



Going to rip apart the crank case tomorrow and upload some more pictures, hopefully get to the bottom the clinking noise. I have a feeling one of the ball bearings broke and that's the sounds of the bearings coming around and hitting the other...just a wild guess

[Coyote]

Depending on the cylinders, you may get by with just new rings. The pistons are reusable in my opinion.. If the cylinders are deeply scored, then you're looking at a re-bore. If the scores aren't deep, you can get by with a quick hone. Be careful not to remove too much stock.
The 550 is infamous for exploding starter clutches. I've seen a lot of them, but you win first prize. That's probably your clanking. Suzuki revamped the design in mid/late 75. Someone on here knows what motor number the new design was implemented. If you want an electric starter, you will need to look at one of a later bike. You can't just replace a few parts. The entire assembly must be replaced. Naturally, those parts are not available from Suzuki. Your only choice is ebay. If you're not sure what you're lookin at, post a link and we will tell you. One way to tell is there is a giant gear on the back of the clutch basket. The center bushings and bearing are nearly twice the size of the old ones.
Some very important things. The points ad you were looking at on ebay are not correct for your bike. Suzuki used 2 different point plates (ignition systems). The ones in the ad are for Nippon Denso Ignition. Your ignition is the more common Kokusan. On the Nippon Denso, the condensers lay flat on the plate. On the Kokusan ignition, the condensers are perpendicular to the plate. Look at your condenser mounts on your motor, then go back and look at the ad. See the difference? Also keep in mind that the Kokusan and Nippon Denso parts are not interchangeable. The condensers are different, the points are different and the points cam is different. They are only interchangeable as a complete assembly, including the cam.
Next up is the rings if you get new ones. The 550 used keystone rings both top and bottom. Keystone rings have a 7 degree angle on one side of the rings. That beveled side MUST face up. The idea behind it, as the piston travels up, the compression forces the ring outward for a better seal. As the piston travels down, the ring relaxes and relieves most of the downward pressure. It's easy to imagine what would happen if any or all the rings were upside down.
Now it's time to rag on you. Clean up man! When you reassemble, everything needs to be surgically clean. I understand that old 2 stroke muck is very difficult and time consuming to remove, but you will be happy when its done.

[bpapachr]

Well I at least rescued this poor bike from its previous owner who didn't give a damn about it! Coyote I am gonna spit shine the engine, cylinder head, etc. now that its off the bike. I bought a lot of degreaser

I was finally able to rip them apart and found that the bearing closest to the alternator has been completely chewed up. This was the clinking noise we were talking about.

I'm waiting on the replacement and I was wondering if there's anything specific to worry about when taking apart the crank? Can I remove the alternator side and replace the bearing or does the whole thing have to be disassembled from the gear side?

I also was pretty meticulous in labeling and taking everything apart properly but the clutch rods fell out and I want to make sure I put these back properly. Can anyone point me in the right direction? Does it matter which one goes into the shaft first?


I also don't understand these three screws that go into the starter clutch housing. They look as the threads have worn down over the years and I cant tell if this is how they are supposed to be?

The three holes on this housing below doesn't have threads so are they even necessary?


Lastly, I also had this gear pop out and want to be sure when its put back together the pin is supposed to sit between the spring on the gear selector?

[Coyote]

1) How does a bearing get that bad? That's horrible!

2) the clutch release rods have a rounded end and a flat end. Both rounded ends go toward the clutch. Short rod first. There are 2 seals the longer rod pass through. The rod needs to be smooth and nick free in the seal areas.

3) That gear is toast. This thing actually ran? See #4.

4) This is the main part of the starter clutch. I am amazed that it is still together.. Usually the roller followers and springs turn to shrapnel. The hub that the rollers ride in is usually mangled as well. You need this assembly if you plan to use the electric starter. There are not suoppsed to be threads in the holes. In order from the back, there is a 3 hole sheet metal cover, then the roller assembly. These parts mount to the back of the primary gear with 3 huge phillips head screws. In case you don't know, the primary gear is the big one attached to the back of the clutch basket. I have come to the conclusion I have no idea what gear that is in pic 3. An idler gear maybe? It's been too many years since I have messed with the older style. I have real photos of the assembly, but it will take me hours to find them.

5) That is in the correct position. If you get those out of position, the bike will have only first gear, or it will shift up but not down