Help with older bike

A

acropora1981

Member
So yesterday I bought my first motorcycle, it is a 1975 Suzuki A100. It started fine for me last night, but then, like an idiot, I left the fuel line open all night. This morning the engine is flooded(I think), and gas is leaking out the bottom of the chamber where the carburetor sits in. I took out the plug, drained the chamber, and was able to get the bike to start for a few seconds, but then it shut off. I took out the spark plug also, and it is wet. I've left the spark plug out to try to dry the engine out a bit.

Also - the choke is labeled with R and S - which is open and which is closed?

Thirdly, what is a good startup order? kill switch, ignition, fuel line, kick? Is it normal for the fuel line to have to be closed, and I have some kind of bad valve? The bike is in good shape, very little/no rust. It needs a good tune up.
 
Yes, a lot of bikes will leak out the overflow or flood the engine with the petcock turned on while the engine is not running.

If i were you, id leave the ignition off, sparkplug out, and kick the bike over 10 or 15 times to clear the extra fuel out of the chamber. Dry the sparkplug off with a rag, put it back in, should fire up.

Also might want to check the oil to make sure you didnt get like half a liter of gas in it, wouldnt be good to run the bike with a lot of gas in the oil. If the oil smells heavily of gas, change the oil.

As for the choke, i guess S would be closed (for start?) and R would be open (for run?). Just guessing here. Take the air filter off and look at the choke to see at which position its closed.

Startup order is whatever you want. If you take a riding course they teach you an acronym but i cant remember what it is. Something like Kickstand, Ignition, Kill Switch, Fuel, Start. I didnt pay attention to it because its got a lot of steps that can vary depending on what kind of bike you ride (some of my bikes dont have a killswitch or a kickstand, for example...).
 
acropora1981 said:
Thanks, I'll give that a try when I get home. If the oil smells of gas, should I replace the oil filter as well as the oil itself?
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Your oil filter will be fine. I would just change the oil.
 
Ok. The manual states SAE 30 - should I use 10W-30 or 5W-30? Or do I have to find one that just says SAE 30?

Also, anyone know where I can get the repair manual for a '75?
 
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acropora1981 said:
Ok. The manual states SAE 30 - should I use 10W-30 or 5W-30? Or do I have to find one that just says SAE 30?
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I am no oil expert and I can't remember but I think 5W ANYTHING is reserved for cars only.. I think 10W30 motorcycle oil is the appropriate oil.
 
I dont think a 1975 100cc suzuki has a seperate oil filter... its probably a mesh grate inside the engine, which no, you wont have to replace (or clean).

Use any oil without friction modifiers. I always recommend the Rotella T. White jug, 5 liters for 20 bucks at canadian tire. Dont use synth in that bike, your clutch will slip like crazy.
 
you guys crack me up! you shouldnt comment about things you know nothing about. the A100 was a 1976-1977 model, 2 stroke bike. the gas is seperate from the transmission oil (10w40). being that the bike is a 2 stroke it has injection oil, which is in a seperate tank. and yes the R is for run and the S is for start on your choke. the bike needs a carb overhaul to fix the float from leaking and never, never use the kill switch to stop the engine unless it is an emergency only. bring your bike to rosey toes and i will tune it up and show you some old school tricks about 2 strokes.
 
Stewart said:
you guys crack me up! you shouldnt comment about things you know nothing about. the A100 was a 1976-1977 model, 2 stroke bike. the gas is seperate from the transmission oil (10w40). being that the bike is a 2 stroke it has injection oil, which is in a seperate tank. and yes the R is for run and the S is for start on your choke. the bike needs a carb overhaul to fix the float from leaking and never, never use the kill switch to stop the engine unless it is an emergency only. bring your bike to rosey toes and i will tune it up and show you some old school tricks about 2 strokes.
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??? What part of what you said contradicted anything i said? :P The gas is obviously seperate from the transmission oil, but if the petcock was left on and it flooded the engine enough to get the plugs soaked, theres the possibility gas made its way into the crank case.

Only thing I was "wrong" about was I didnt know it was a 2 stroke. If people dont say its a 2 stroke and are working on their bike, im going to assume they know the difference between the mix oil tank and the gearbox. If not, they probably should crack the manual before tearing into the bike to get it running.

But yeah, knowing that, I change my recommendation. Use Rotella in the gearbox, and Amsoil 2 stroke oil in the mix tank.

*edit* but yeah if you are having problems and dont know much about your bike, I would say take it up to rosey toes. Dave is definitely a helpful guy and will tell you lots of stuff about your bike, you will learn a lot.
 
Ok...good info here. The oil does not smell like gas, so I have left it.

I bought a new spark plug today and the bike started right up. Problem; after first start, it wouldnt start AGAIN, check plug, again, WET! With black grease and whatever.

Got the bike started again. It doesn't want to idle even with choke fully open; only wants to stay on with a bit of throttle. Exhaust is a bit smokey, and its making a lot of popping noises. For now Im leaving it off. Im going to grab a new battery tomorrow, because the lights are very dim on the bike... I would bring it up to Rosy Toes, but cycle werx is a 20 minute walk and a 4 minute drive away, and I have no truck to load this thing on :(

I will not use the kill switch again. What is the proper method to stop turn the bike off?
 
bobjohnson said:
??? What part of what you said contradicted anything i said? :P The gas is obviously seperate from the transmission oil, but if the petcock was left on and it flooded the engine enough to get the plugs soaked, theres the possibility gas made its way into the crank case.

Only thing I was "wrong" ....
*edit* but yeah if you are having problems and dont know much about your bike, I would say take it up to rosey toes. Dave is definitely a helpful guy and will tell you lots of stuff about your bike, you will learn a lot.
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Where you were WRONG was pontificating about a bike you know absolutely nothing about... which is quite typical around here
So
Carry on.

ps: when I read "Dry the sparkplug off with a rag, put it back in, should fire up." I laughed so hard some coffee came out of my nose... which me me laugh some more.
Keep up the good work!
 
call ted, he will come and get your bike 416-241-2523. again ,your carb needs dealing with, the float level is your problem
 
Stewart said:
call ted, he will come and get your bike 416-241-2523. again ,your carb needs dealing with, the float level is your problem
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Who is Ted?

I will most definately be getting the bike tuned up and carbs cleaned; it still has to be certified etc.

For those interested, here is the wee little fella

SUZA100.jpg
 
ted rose of rosey toes motorcycles, he will cert your bike for 40$. this is a rotory valve carb 2 stroke engine where the piston is the valve
 
2 strokes are a dieing breed lol, I love that every one assumes its a 4 stroke. If its worth anything I agree with Stewart, your carb needs adjusting. Your mix may also have too much oil in it (fouling the plug).
 
those little bikes can be tempermental
your bike is a 2 stroke rotary valve,seperate oil tank for oil injection
make sure you use 2 stroke oil there
if you are not sure what is in the gas tank drain it and start with fresh gas
gas may be old and someone might have premixed 2 stroke oil with it
start of with pulling the plug shut off gas and kick like hell for a while(ignition off)
clean the plg electrodes with sand paper and if you have a propane torch burn off excess oil
try starting the bike with the choke off if it starts tap the carb float bowl a few times and shut the gas off this may disloge andy debris that is keeping the float bowl open
if you are still fowling up take the carb off and clean the float bowl valve
good luck
 
Just wanted to update my thread here;

I managed to dismantle, clean, rebuild, and re-install my carburetor. Bike runs very very well now. The fuel line was almost completely blocked with gunk where the line attached to the carb, and the float was sticking due to deposits inside the float bowl where the float articulates (the little bar that it articulates on). I cleaned it all out with Carbu Clean from FS. Of course, I ripped the damn float bowl gasket in the process, but got a new one from Snow City for all of $3.00 :)

Next I replaced the bulbs and the signal relay - whomever owned the bike before had made the mistake of thinking that the bike would take 18W flashers, but actually its supposed to take only 8W, so got those, installed the new relay, and boom, singals working.

After that I remounted the brake light switch, which still works, it had just come un-attached from its bracket, so the brake signal wasn't responding to the brake being depressed. That one was easy!

Now I have to figure out the damn headlight. Its one large welded together peice - like the bulb is a PART of the reflector? Seems very wasteful to me. Anyway, I cut out the old bulb with a rotary too, leaving a nice clean hole. I put in a 25/25W 6V headlamp and soldered 3 connectors to a 2 connector bulb - one of the connections should just go to the base of the bulb. It seems very dim. So did the other old one, but I'm not really sure how to proceed from here. Its possible the rectifier isn't working properly but I'm really not that technically inclined. The old bulb was 35W, but the manual calls for 25W. The old bub was also very very, even on hi setting. The headlight appears to be the only bulb that requires the engine to be running in order to turn on.

I also have no idea how to set the idle of the engine - if I were to guess, I would say its idling at a fairly high setting. There are two screws to play with to set the idle, but I really don't want to mess with them!
 
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