At a loss... Solved?

Ok so I just ran it a bit after work. It was acting up a bit, stumbled and died. I adjusted the idle speed and fired it up(warm no choke) and it holds an idle. Seems pretty responsive to the throttle. The plugs are looking better too. Maybe a little rich? I do need an air filter.





I don't if this will work. Here is a video so you can hear how it sounds.

http://i1243.photobucket.com/albums/gg5 ... d9eddc.mp4

 

Air filter is a must, unless you're running pods.
Those plugs are ok, better than being too lean.

 

No pods. I have a filter. It's just older than dirt.

 

Sounds like your missing firing on a couple cylinders, sounds more like a v twin than an inline 4

 

I was suspecting something like that. How do I go about diagnosing/fixing something like that?

 

Start it up and put feel the headers in front of the bike when it idles. The ones that don't get warm are the ones that aren't firing. You can also let it idle and take off a spark plug cap. The idle should decrease if that cylinder is firing because you're removing its spark.

 

Ok so I just went out and messed with it a little more. If I pull any of the caps off the plugs, the idle does go down, some more drastic than others. I did notice the number 4 header pipe stayed pretty cool. I could actually grab it, while the other 3 where too hot to touch. The engine actually dies when I pull the cap off of that plug.

The plug also looks pretty weird.

 

DON'T PULL THE SPARK PLUG CAPS OFF OF A RUNNING ENGINE!!!!!!!!!!!!!!! YOU CAN FRY YOUR TCI BOX!!!!!!!!!!

Sorry for the yelling, but that is bad advice. Your ignition system is a wasted spark system. Pulling one wire actually stops TWO (2) cylinders from firing, as the high voltage current goes down one spark plug wire, across the gap in the plug, through the engine head, across the other gap in the plug, and up the other spark plug wire to complete the circuit.

Not only are you not just testing "that" cylinder, but the high voltage signal needs somewhere to go, and can end up in your TCI box where it can arc across the delicate (and closely spaced) solid state circuits. If you want to verify spark, (bike off) you pull the plug, GROUND IT TO THE ENGINE, then turn over the bike.

For only one cylinder to not fire, you've either got a fuel delivery problem (sync off, mixture off, air leaks, sticking slide, clogged jets, SOMETHING is off on the fuel delivery), or there's no spark (gap or something else with the spark plug is wrong, coil would cause 1 AND 4 to not fire), or the copression is very low in that cylinder (did you retest compression with a new gauge?).

I would wager, give your (very bad) spark plug cap removal test, that your sync is way off, and #1 is pulling along #4, and maybe even the other cylinders. When you took it out of the mix (by pulling #4's plug cap), the engine died because it's strongs cyldiner stopped firing.

 

Just re-read an earlier post, a 3ft long compression tester hose can make it difficult to test your compression. There should be a valve at the bottom of it, and really should be under 12 inches long.

 

Cool, thanks for the info. I'm starting to think(hope) it's just a sync problem. I have only done a bench sync on it so far. The slides all seem ok to me. They all raise with minimal effort, and drop back down at te same speed. They all went clunk when I put them together. Every passage and jet in the carb seems to be free and clear as well.

In previous testing, i did pull that plug out and saw that it was sparking.

 

Just re checked the plug on number 4. It's getting spark. It actually managed to shock me after I turned off the ignition.

That header is staying pretty cool, and the grounding strap still looks new. So maybe somehow that cylinder isn't getting fuel?

 

Not being in sync will cause all kinds w.eird running conditions. Sync it and set the mixture screws. Color tune helps for that

 

Cool. Maybe I will try to make the 2 bottle manometer tonight.

Thanks

 

Make a four tube one instead.

 

Any links for one?

 

Supplies:
PVC tubing, 25 ft (I think 3/16 inner diameter, but bring your carb bowl to the hardware store.

Three (2) or four (1) prong "T" connector. I ended up ordering some from granger, but I've seen them in the vacuum testing section of autoparts store.

Two prong tube joiner (4).

2 red straws from spray cans (wd40, carb cleaner, brake cleaner)

ATF-4

Board to mount the four lines to. At least 3 feet in length.

Instructions:
1. Cut the tubing into four equal lengths. Connect using "T"s
2. Mount to board, I used long staples.
3. Make restrictors using the two prong joiners. Cut the red straws in half, then glue them into the joiners. Be sure not to get any glue in the straws. Once glue has cured, cut off excess straws.
4. Fill sync gauge halfway with ATF. You can try to make a funnel and pour, or if you have a vacuum bleeder, dip three hoses in ATF, and suck it up using the fourth connected to the bleeder.
5. Cut 6 inches off the end of each tube, and connect using the restrictors.
6. If there are any air bubbles, make sure they get to the top of the fluid.

 

Thanks

 

I just backed out the mixture screw on number 4 until my engine sped up a bit, and tinkered with it from there. The header seemed to get a lot hotter, and the bike started to sound a lot better. The throttle response was definitely a lot better. Its starting on the first push. Choke when cold, no choke at all when warmed up. It doesn't seem to have that weird loping sound anymore.

Hopefully tomorrow I can get some cash together and build a manometer and get it nice n happy.

 

Also available at your local petstore in the aquarium section.