My bike wont start!!!

New guy here, hello everyone. I bought a 1982 Yamaha Seca XJ550 about 6 months ago. The PO said he bought it from a guy that laid it down. Anyway the guy I bought it from said that he had it running for just a short time but it never ran for a good legth of time. So I paid him $300 for the bike and thought I would give it a shot. First thing I did is replaced all the old fluids with new, also replaced the spark plugs with new. I also replaced the timing plate. After all that I went to start it and it would turn over, but never started. Found the kick stand sensor issue and fixed it. Next tryed to start it and it started, ran for about 5 min then died. The ignition button wouldnt respond. Waited a few min and tryed again. It tryed to turn over again but would not start...again. I checked the petcock and its getting fuel. I pull the plug and arced them off the case, it has spark. Set the choke all the way open and pegged the throttle all the way open, tryed to start it and it started and it ran for about 5 min then I started to take the choke off and it died. I pulled the plugs cylinder 123 were clean but 4 was black. What do I do next?

 

Have you try cleaning your carb? How is the compression?

 

Bikes that ran but don't start after sitting around for some time are Prime Candidates for a complete Carb Cleaning with Bore Polishing.

To see if the Bike will run and if you have a Fuel Delivery issue; conduct the following test.

Spray some Starting Fluid or Carb Cleaner into the Rubber Intake Orifice of the Airbox.
Try and run the Bike.
If the Bike tries to Start upon having the Airbox sprayed; the Carbs are most likely in need of a thorough Cleaning.

 

Carbs have already been cleaned. Starting fkuid already tryed. There is no air box...sorry guys, just alittle frustrated. I try to spend two hours a day hunting and troubleshooting issues and it still sounds the same. It just keeps cranking but no start. Thanks for the suggestions...what next?

 

Wrong jets? My carbs were rebuilt with a 650 carb rack. Not cool. Check your diaphram needles and main and pilot jets maybe.. Is it flooding the plugs out?

 

When you you say there's no airbox,does that mean no air filter at all or is there pods?

 

Its only flooding carb #4. I ve checked carb #4's floats, they appear to be fine visually, not sticking. Yes, no airbox or air filter pods...nothing. And my throttle does not respond like the bikes I've had in the past...sticking.

 

Yikes, either find an airbox or get some pods on that thing. Last thing you need is unfiltered air getting pulled into that engine. You think you've got problems NOW...

 

On it right now! But do you think it will cure the issues I have right now?

 

I really can't say - the one blessing I've had with my bike is there have never been any fuel-flow issues (looks for wood to knock on, quick!). I do know that it won't hurt, though, and it's stop the bike from sucking dust and dirt into nice clean carbs when you do get it running...

 

These bikes weren't set up to run (on the stock jetting anyway) without an airbox. Even if it ran fine, if you're now trying to get it to run with just open carbs it probably won't RUN although it will fire.

You can install pod filters which will start you into a rejetting and tuning circle of hell from which you may never return; OR you can pull the engine and install a stock airbox. You cannot replace the airbox in a Seca 550 without pulling the motor, I've tried.

Either way, it's not going to run (for long anyway) with the carbs simply open.

 

Notice I'm learning, Fitz - I recommended an airbox OVER pods this time.

 

Seca34:

Lets tune that bike up so its sitting on the rezor edge of high performance.
Get a airbox
Get some Airbox boots and clamps
Get all that stuff started to your location for use after you Yank the Carbs and Clean them.

Find a neighborhood kid who's got a laptop that can do a video hook-up and I'll run shotgun for you while you get the carbs Cleaned.
Then, ... we'll Tune it. Right.

I got a set of Carbs on my end I'll use while you are doing yours.
Once we get rolling and smooth-out the schedule ... 5 hours.
Done.

 

Ordered the air pods today. I also did the bench set-up on the carbs. Inspected the intake manifold boots, and there are no cracks or holes. So I will start this up again when the air pods arrive. And I will probably have to re-jet since their air pods. Although I must say that I've worked on everything from fighter jets, helicptors and automobiles and to have something like this be so tepermental that with the slightest change in air volume will completely shut it down. Anyways thanks everyone and I'll start this again when the pods arrive.