Suden loss of ALL power!?@#$%

[ColoradoPI]

Hey guys, I'm new to the forum. This is my first post, haven't really had much need to post anything of my own. There's soo much good info here. Awesome site.

Anyway, here's my problem. By the way this might be sort of a long message, want to give as much detail as I can. Alright so, I bought a '78 XS11 a few months ago. It had been sitting for over a year, but garaged and taken care of. So I've been working with it, took the carbs off a few times, hooked up a sync (all's good). Then realized I needed to colortune. Cool, so I did.

1 and 2 are getting a bright blue flame, but 3 and 4 have only a very small, dull yellow spark. Plugs get fouled up after 20 miles or so. Sometimes I can get somewhat of a blue from 3 or 4, but not anywhere near 1 and 2. So that's what I've been messin' with. Thinking it's possibly the pick up coils?

So here's the major issue right now. Yesterday I res-sync the carbs, 3 and 4 were a little off. Colortuned as best as I could, put in clean plugs. Took it out for a test, just up and down the street a few times. It ran fairly well, not great, but nothing unusual.

When I got back, I noticed the crank breather tube was smoking a bit (white moist smoke). Thought that was odd, checked the oil, a little low, but not anywhere near empty.

I let the bike cool an hour, started it up again, put it in gear, let off the clutch and nothing happened. Reved up to 5 or 6k before it would move foreword about an inch. I'm stumped guys.

Today I was messin' with it. Feathering the clutch...a lot. Inching foreword and rolling back. Finally could get it to roll foreword and gain a little speed. Got the rpms to about 8, then shifted gears. After a trip up the street it seemed to be doing a lot better, but still a power loss.

What do you guys think? Any Ideas would be greatly appreciated.

P.S. All 4 pipes seem to be in the same heat range.

[red bandit]

If the problem is #3-4 it's fuel. Check your fuel line for a good flow maybe need to clean the carbs.
No power to rear wheel, check your oil level on center stand, sounds high.

[AlanB]

Hi ColoradoPI,

Welcome to the forum; some of the experts will be along in a minute, after us amateurs say "Hi"

There is a lot of info on "What to check" and "What to do" to a long-stored bike in here somewhere.... start by working through that lot; most of your problems may disappear. I think it is listed in the "Tech Tips" section.

The "white moist smoke" from the breather is just the bike getting rid of the condensation which has collected in the oil. It gets there in humid storage, but mainly comes from having the bike sit idling for long periods; once the oil is properly hot, it leaves!

You will probably want to change ALL of the fluids before it goes back on the road.

Ignition parts are paired up through cylinders 1+4 and 2+3, Fuel feeds are paired 1+2 and 3+4, so your problems are fuel related, not ignition. Since both are similar, start by looking at the fuel feed out of the tank; do both sides run equally?... is the tank dirty/rusty inside?

Oh, and post some pics; we LIKE pics!

AlanB

[ColoradoPI]

Originally posted by AlanB
Hi ColoradoPI,

Welcome to the forum; some of the experts will be along in a minute, after us amateurs say "Hi"

There is a lot of info on "What to check" and "What to do" to a long-stored bike in here somewhere.... start by working through that lot; most of your problems may disappear. I think it is listed in the "Tech Tips" section.

The "white moist smoke" from the breather is just the bike getting rid of the condensation which has collected in the oil. It gets there in humid storage, but mainly comes from having the bike sit idling for long periods; once the oil is properly hot, it leaves!

You will probably want to change ALL of the fluids before it goes back on the road.

Ignition parts are paired up through cylinders 1+4 and 2+3, Fuel feeds are paired 1+2 and 3+4, so your problems are fuel related, not ignition. Since both are similar, start by looking at the fuel feed out of the tank; do both sides run equally?... is the tank dirty/rusty inside?

Oh, and post some pics; we LIKE pics!

AlanB

Thanks Alan. Fuel seems to be flowing good up to the carbs. Guess I'll have to take 'em apart again. I post up pics as soon as I can.

Oh, and the oil level. If anything, it's a little low.

[manshack_one]

don't forget to check the oil on the centerstand, not the kickstand. my previous owner got me good with that one. 7 quarts!! You may already know that. I didn't.

[mro]

Good idea to have a fan blowing on the engine when tuning the carbs etc. or anytime your letting it sit and run.

Clutch adjustment described very well in manuals and only takes a few minuets.
What kind of oil you using?

Plugs get fouled up after 20 miles or so
Just 3 and 4 or all of em?
What's the float height set to?
How many turns out have pilots been set?
Have you checked the plug caps for corrosion? (they unscrew from the plug wires)
Stock exhaust/air box?


mro
BTW, welcome to XS land...
What model XS do you have?

[ColoradoPI]

I've tried to not let it heat up at all when tuning. I've gone probably about 300 or more miles on the bike since I bought it. The only real problems I've had were the 3 and 4 plugs keep fouling. It seems it's rich whether the pilot screws are all the way in/out/half-way/whatever.

It always ran great with freshly cleaned plugs. Up until the other day when I lost all power.

I know, I'm a dumbass...I haven't put new oil in it. The PO had just put new oil, filter, indie filters, carbs rejetted. He kept it clean. Just didn't take the time to sync. Got tired of the project.

Can't remember what I set the floats to, they're all the same and to specs.

Stock exhaust.

Plug caps are good and no vacuum leaks either.

Like I said earlier, with a little TLC, I got moving fairly well up and down the street. I have a feeling that if I rode a little while longer it would've gone back up to normal power. But I want to figure out what the problem is first before I ride it much anymore.

[ColoradoPI]

P.S. It's the 11E Standard

One petcock closed off. Fuel line T's into carbs.

[DiverRay]

If you have the engine turning, but no power to the rear wheel, it's probably the clutch. Do the adjustment with the screw that is behind the cover on the right side of the engine. It comes off with the two oval head screws, and the cable hook up is there.
3&4 fouling plugs MAY be a blocked vent. There are two lines to each pair of carbs, the bottom line is fuel, and the top line is the bowl vent. Make sure the vent is open all the way to through. As the PO put on pod filters, what did he do with the vents??? Best idea is put a fuel filter on the end of each vent line, after running them up under the tank.
Welcome to the site, and do post pictures.

[manshack_one]

AlanB gave me some good advice one time. You have to put a 100 mile ride or so on it before you can really tell what kind of problem you're having. It doesn't help to try and adjust a bunch of stuff on the carbs without the bike running under load for a while. If you can't do 100 then try at least 10 miles at 55 mph or better to blow the cobwebs out. Like I said before, my po put in 7 quarts of oil, let gas overflow to the crank case and had all the idle mixture screws all the way out. I changed the oil the right way, reset all the mixture screws and ran it hard for 30 minutes on a country road. I left the house looking like a mosquito spray truck and came back with exhaust you can only smell instead of see. Just my .02 I've caused more problems by trying to tune the carbs right after cold start idle than you want to know about.

[AlanB]

Hi ColoradoPI,

I think the link you need is;http://community.webshots.com/user/john80sg

Hope this helps!

AlanB

[manshack_one]

Not to get too far off topic, but why does the exhaust cross over like that on Twilite Special? 1&4 to one side and 2&3 to the other?

[ColoradoPI]

DiverRay, Mro! Good Job! I feel like an idiot. Thought the clutch would've been too obvious, too easy. And for it to go from normal to way bad so quickly.

Bike's back to working order. Well at least as far as it was before the other day.

What a relief, thought something major was jacked up real bad.

Anyway, still blowing smoke out the breather. And still doesn't purr like it would with 3 and 4 rockin' like they should.

I'm gonna set it at a very low idle and tune the pilots by ear for now.

Hey what do you guys think about maybe a bad diaphram? I'll have to set a day aside to take carbs off again.

[John]

Off topic is right!

Originally posted by manshack_one
Not to get too far off topic, but why does the exhaust cross over like that on Twilite Special? 1&4 to one side and 2&3 to the other?

Just wondering what some pics of my bike have to do with the topic of this thread. I don't have a problem with it, in fact I like it when people look at my pics.
Hey 'Shack, the pipes are made that way. They are Jardines, and folks around these parts like to call 'em 'sketti pipes.

[DiverRay]

Colorado,
I would NOT worry too much about the diaphrams. If 3&4 is the problem, it's in the fuel delivery or the vent system. You may also be so far out of sync, that the bike is trying to hold up 3&4, or 3&4 is trying to hold up 1&2.
DO NOT BOTHER TRYING TO TUNE THE CARBS!!! You need to FIX THEM FIRST.
Smoke out the breather should NOT be a problem until you have AT LEAST 100 GOOD miles on the bike. You can try and pull the spark plugs, and put a little Seafoam or Berryman's B12 down the holes. Let it set for an hour, and then turn the engine over a few times, reinstall the plugs and fire it up. That should loosen up any stuck rings. If you have access to a compression tester, that may be a good idea. All the plugs out, and hold the throttle WIDE OPEN as you do the test.