81 GPz550. cylinders 1 & 3 wont fire???

Got fuel got spark.. Timing off by one chain link? Bent valves? Help! Lol also have don't have my manual.. do the spark plug wires connect to the coils in line corresponding with the cylinders below?could it just be timing?cylinder numbers two and four the spark plugs have good burn marks and on 1 & 3 it doesn't even look like the cylinder has been Firing, because the plug still looks brand new, which they all were when I put them in. so its timing, bent valves, or I have spark plug wires 1&3 in the wrong spots maybe?oh and also it only backfires at low rpm's when it's just about to die. just a couple low rpm pops right before it dies sometimes. sometimes it will backfire of the exhaust or back through the intake but still only when its about to die At low rpm. Help lol

I can put my hand right on the header pipes For cylinders 1 & 3 even after minutes of running, they just aren't firing...

Where to start... first you need a manual of some kind, factory service manual is best.
Second, you have two ignition coils. The left one goes to cylinders 1&4 the right one to 2&3.
verify that is true and correct.
Third. Is your valve clearance set to specs on all 4 cylinders?

Start by checking these things and I bet you find your problem. Paul

For some reason, the smaller 4's ignition coil & sparkplug configuration is opposite from the bigger 4's. Smaller 4's: 550's,650's,700's, & 750's.
Larger 4's: 900's,1000's & 1100's

The wiring is reversed for the 550’s 650‘s and 750‘s, that is the RIGHT coil primary will be two wires, RED and BLACK with the secondary(sparkplugs) going to #1 and #4.

The LEFT coils primary wiring would be again two wires, RED and GREEN, with the secondary(sparkplugs) going to #2 and #3.

so from sitting on the bike the coil ports straight across should be connected with the wires such as 1 4 | 2 3? because I had it 1 2|3 4 strait across lol...

MFolks wrote: For some reason, the smaller 4's ignition coil & sparkplug configuration is opposite from the bigger 4's. Smaller 4's: 550's,650's,700's, & 750's.
Larger 4's: 900's,1000's & 1100's

The wiring is reversed for the 550’s 650‘s and 750‘s, that is the RIGHT coil primary will be two wires, RED and BLACK with the secondary(sparkplugs) going to #1 and #4.

The LEFT coils primary wiring would be again two wires, RED and GREEN, with the secondary(sparkplugs) going to #2 and #3.

Thanks for that Mfolks... I was working from my memory and experience with 1000's and 1100's!

There is a lot of 550 info in my signature.

Download all of the manuals and read them all in your spare time. There are quite a few in that link.
You can get the wiring diagrams there too.

And definitely read the valve train warning before you ever take the valve cover off.

And yes, the right coil gets the small black wire and fires cylinders 1 and 4.
The left coil gets the small green wire and fires cylinders 2 and 3.

Cylinders are numbered 1, 2, 3, 4, left to right when sitting on the bike.

Ok. I got the wires all hooked up properly now and it sounds Awesome once again and seems to run amazing for about a minute or so and then it just wants to die and then it's hard to start. hoped on and Rode it bout 150ft and it died... Now what lol...

Check the fuel flow. Sounds like it may be running out of gas, or the petcock isn't flowing, or there is a paper inline filter stopping the flow.

If you're using Ethanol in the gas(most of us are without knowing), the fuel lines may internally swell, or if a plastic gas filter is being used, it may have the glue holding the paper element together dissolve, coating the filter, severely restricting gas flow. Ethanol in today's gas attacks all of the rubber fuel system's parts, making those a yearly time change items.

MFolks wrote: If you're using Ethanol in the gas(most of us are without knowing), the fuel lines may internally swell, or if a plastic gas filter is being used, it may have the glue holding the paper element together dissolve, coating the filter, severely restricting gas flow. Ethanol in today's gas attacks all of the rubber fuel system's parts, making those a yearly time change items.

Yes, and the brass parts are being eaten up pretty badly too.

okay, update!... Was running out of fuel... Err not enough flow only stays running when petcock is in PRI position..... Why? Jesus Christ she fu*kin GOES now! when I did the head gasket I made sure to remove all carbon deposits from the combustion chamber the tops of the Pistons we're almost like a Polish same with the combustion chambers and bottoms off valves. it was caked with carbon before that like a ridiculous amount has way more power now!!! Very happy.. So just new petcock I guess or what's up now? Thanx all, cheers. Stoked.