Wont start, not even a cough.

[rescue50]

Hey guys, I'm at my wits end with my 81 xs special. Ran fine last year, started and ran it at regular intervals throughout the winter. Never had any trouble getting it to fire up. This spring...nothing, not so much as a hiccup. I've got good spark, I've boosted the bike off my truck just in case the bike battery wasny pushing enough amps. Carbs could probably use a cleaning but again, it doesnt even sputter. The only thing I did over the winter was to adjust the clutch, but I cant see how that could be a related, or am I an idiot.

Rescue50

 

[xschris]

New plugs and fresh gas (also drain carbs). Also never try to start a bike with a running car or truck. It will fry the electrical components in the bike. A truck/car puts out waaaay to many amps for the bike to handle.

 

[rescue50]

Thanks xschris. I'll drain out the fuel this weekend. I figured that it would be okay since a: it was stabilized, and b: it ran in this fuel a month or so ago, but i'll try anything at this point. The plugs were new last year, less than three hours run time on them. Would you still suggest changing them. This is my first bike, I've never worked on anything with points before, and my last carbureted vehicle was as 79 impala I had about twenty years ago.

 

[Rambo814]

It's been a while since I've used the electric start, but when using kick start you can not pull the cutch lever in, or disengage the clutch. Is it possible you over adjusted the clutch and it is not engaging enough?

 

[Scorpio1963]

Do the lights come on when the key is turned on?If so I would try checking the kickstand relay.Also take the estart side hand control apart and check your connections.Theres a thread of mine called ignition problem look it up ,theres tons of info in it.

 

[xschris]

Thanks xschris. I'll drain out the fuel this weekend. I figured that it would be okay since a: it was stabilized, and b: it ran in this fuel a month or so ago, but i'll try anything at this point. The plugs were new last year, less than three hours run time on them. Would you still suggest changing them. This is my first bike, I've never worked on anything with points before, and my last carbureted vehicle was as 79 impala I had about twenty years ago.

A lot of idle time can foul plugs. I don't even start the bikes unless I take them for a good long run.

 

[rescue50]

It's been a while since I've used the electric start, but when using kick start you can not pull the cutch lever in, or disengage the clutch. Is it possible you over adjusted the clutch and it is not engaging enough?

I wondered about that, but figured that the clutch 'safety' I'l call it, would interrupt the electrical circuit, and that since I do have spark at the plugs when it turns over, that the electrical system must be functioning properly. Is this faulty logic?

Thanks.

 

[rescue50]

Do the lights come on when the key is turned on?If so I would try checking the kickstand relay.Also take the estart side hand control apart and check your connections.Theres a thread of mine called ignition problem look it up ,theres tons of info in it.

Yes, the lights do come on when the key is turned. I was actually reviewing your thread on ignition at work last night, but as I said to Rambo814, assumed that if I have spark at the plugs when the motor turns over, that the electrical system must be functioning properly, and that the issue was then fuel delivery . It seemed strange though that the motor would not even sputter once.

Thanks.

 

[Scorpio1963]

Your bike should be able to start in neutral without the clutch engaged.since you have spark at the plugs if your getting fuel it should run.Unless you have a broken clutch wire black and green or other fault there its possible it might not run but then again Ive been told you can do with out it.
Your problem is so similar to mine its crazy.Did you try either when to tried start it,did it flood?i wish I could help more because I don't why my bike all of the sudden decided it wants to run this year

 

[rescue50]

I'll be honest, I don't think it's ever flooded which is what pointed me towards a fuel problem. At least I haven't noticed a strong smell of gasoline, even after trying to turn it over for a while. I can't say for certain though. As I've never owned a bike before, I've no basis for comparison. I've at least got a few more things to try out now thanks to you guys. It'll have to wait for the weekend though. Is frustrating. I bought the bike at the end of last season, now that the new riding season is he, it doesn't want to go. Argh...

 

[Arclight88]

Just a thought - have you tried starting fluid in the air intakes? I have used this on the occasions when it has been 4-5 weeks between starts with good results.

 

[rescue50]

Just a thought - have you tried starting fluid in the air intakes? I have used this on the occasions when it has been 4-5 weeks between starts with good results.

I tried some sea foam spray cleaner, but no, not starting fluid. The fact that it didnt even attempt to fire up made me think the problem beyond a bit of ether's ability to fix. It cant hurt though can it? Ill pick up a can on the way home from work. At this point Ill give anything a shot.

 

[lemonhead]

Can hurt if you use too much. Some "mechanics" used a whole can or more on my brothers car and blew two of the pistons out of the bottom of the block. The "mechanics" didn't realize the air filter was compromised and was completely blocking the air flow, so they decided ether was the cure. Ether is very volatile and will ignite at the slightest spark and sometimes on compression alone, which is why we use it to start stubborn engines. Too much ether just turns your engine into a cannon, where the rod and piston are the projectile. If a quick whiff of ether doesn't get you any results, I'd check out other causes to your problems.

 

[rescue50]

Can hurt if you use too much. Some "mechanics" used a whole can or more on my brothers car and blew two of the pistons out of the bottom of the block. The "mechanics" didn't realize the air filter was compromised and was completely blocking the air flow, so they decided ether was the cure. Ether is very volatile and will ignite at the slightest spark and sometimes on compression alone, which is why we use it to start stubborn engines. Too much ether just turns your engine into a cannon, where the rod and piston are the projectile. If a quick whiff of ether doesn't get you any results, I'd check out other causes to your problems.

Good advice. I guess what they say is true, all things in moderation . If the jets are gummed up, will ether clear them out?

 

[rescue50]

A lot of idle time can foul plugs. I don't even start the bikes unless I take them for a good long run.

This is likely going to seem like a dumb question to those of you who know, but...here goes.. I have a working knowledge of carburetors. I took small engines in school, and rebuilt a couple of carbureted car engines in the auto shop. I generally speaking, know the parts, throttle plate, choke plate etc. When I took the emgo pods off the carbs, I expected to see the choke plates. Instead, I was looking at what appear to be two brass semi cylinders that slide up and down. They are visible in xschris's profile pic above. What am I looking at??? Pulling the choke knob has no effect, so is not the choke.

 

[xschris]

If you have emgo pod filters that is a good part of the problem. They suck They have an inner lip that blocks the vent in the carbs. They also have many other bad qualities. Using the stock H-pipe with the stock air filters and boxes is the best but if you are going to use pods use uni's on the H-pipe. The carbs we have are mikuni BS34 CV type. Google them or look in the manual for a break down of them. They are not like most small engine carbs. Any other mods to the bike?

 

[Scorpio1963]

what you are looking at is the slide needles that operate the diaprams inside the carbs.theres a little piston that also moves up and down.That would be on the intake side of the carbs,reverse side you would see the butter fly plates.

 

[lemonhead]

Ether won't clear out the jets, it actually bypasses everything in the carb aside from the throttle slide and butterfly valve. Your best bet is to pull the carbs, pop off the bowls, pull the floats & needles and run a fine wire down the jets and passageways with a little cleaner. If you have a blow-off gun with a rubber tip, you can press the gun against the jets and blow junk out of them (wear a face shield, it's easy to blast stuff back into your face). Then, just carefully reassemble everything.

The choke knob simply lets more fuel out, rather than closing off air flow. When you turn the throttle, the butterfly opens, letting more air through. Some of this air flows through those ports at the top of the intake side of the carb and actuates a diaphragm that lifts the throttle slide (the brass cylinder) which lifts the main needle, allowing even more air and fuel to flow through to the cylinder.

 

[rescue50]

Well, an update.... Tried the starting fluid, to no avail. So it's time to pull the carbs. I'm grateful for all the advice so far. Can any of you fine folks point me towards a good how to on the forums. It'll be my first time opening up a carb so simple is good. You know, primary colours, no big words....carb work for four year olds. Lol.

Thanks again for the help.
Rescue50

 

[kshansen]

Also never try to start a bike with a running car or truck. It will fry the electrical components in the bike. A truck/car puts out waaaay to many amps for the bike to handle.

I'll tend to disagree on this statement. I don't know haw having too many amps could hurt anything, components will only draw they amps they need to do their normal jobs. Actually they will draw less amps when connected to a bigger source like a car battery as amps will go up in direct relation to drop in volts. Study up on OHMS Law.

I personally ran an XS650 off a car battery for several years with no problems. Battery was installed in the sidecar. A typical car battery may have a cold cranking amp rating of 800 amps. Where the alternator may be 60 to 90 amps so the output from the running engine is only a fraction more than what a battery alone would be able to supply.

If having too many amps available would cause an electrical component to fail how come when you plug a little fan into the grid that has thousands of amps available it does not push too many amps in to the fan a burn it out?

Anyone care to correct me with a good explanation?

I will make one concession, being hooked to a large battery could allow someone who was not using their head continue to crank over the engine way beyond a reasonable amount of time and burn out the starter.