Fixed some stuff and now it runs worse (SOLVED)

I recently fixed a few issues with my maxim 650. It had cracked carb to engine boots and the previous owner rigged up some pvc and rubber intake box to carb boots that kept coming apart. I had some issues where the bike would run pretty good but I would get the occasional backfire and some missing like it was really lean (probably cuz all of the air it was getting).

Using info from this site, I used black RTV and bicycle tubes to repair my carb boots. I then replaced my BS airbox boots with the plumbquik ones I read on another thread. A little wrestling (ok a lot of wrestling) and everything is back together. The airbox boots are tight and there seems to be no leaking from the carb boots.

I rolled the bike outside and it fired up pretty quickly with the choke on. It sounded quieter and idled nicely. I revved the engine and quickly noticed a miss. It sounds like at least one cylinder is missing. I expected this going from a bike that usually was lean with the cracked boots but one thing puzzles me. Why does it now only run with the choke on?

I haven't pulled the plugs or anything, I am not touching it until at least tomorrow but any idea what this may be?

 

Re: Fixed some stuff and now it runs worse

a carburetor issue or a fouled plug as a result of the issues you were having previously.

Or any one of a number of other possibilities from a loose plug wire cap to a tight valve or anything in between.

 

Re: Fixed some stuff and now it runs worse

Could also be that just running the bike dislodged some gunk that traveled down stream to the Pilot circuit, ruining your idle.
You do have an inline fuel filter??
As Fitz said, could be many things.

 

Re: Fixed some stuff and now it runs worse

Only running with choke on is often a sign that a pilot jet is clogged.

Do a quick check on your plugs, swap them around and make sure the caps are on tight. If that produces no change then you'll want to pull the carbs and check the jets. Fun fun! ha.

 

Re: Fixed some stuff and now it runs worse

Ok, I feel really stupid if this is my answer. In the process of fixing the other items that I mentioned at the beginning of the post, I fixed the vacuum line to my petcock (bypassed by p.o. for some unknown reason) and repaired an old fuel line. When I hooked up the vacuum line to the petcock, fuel flowed fine but when I tried to start the bike, it seemed as if it wasn't getting enough gas. I double checked the petcock and it was ok.
I re-disconnected and bypassed the line and ran it on PRI. It started but wouldnt rev. I thought I fixed the fuel problem. Today, I tried again and it would only run for a few seconds. I got aggravated and took my kid to the park.

After he went to bed, I pulled the plugs and cleaned them. They were all dry and pretty clean which made me think "lack of fuel" again. A thorough recheck of the bike and....wait for it.....THE GD FUEL LINE WAS KINKED AND ALMOST CLOSED COMPLETELY!!!!! I corrected this and gave it a try. Fired right up and didn't seem to miss. I shut it off after less than a minute so I didn't wake my kid (bike has an open header). I will try again in the morning and see if that was the problem. If so, I feel REALLY stupid wasting everybody's time on here. Thanks for the support this site is awesome.

 

Re: Fixed some stuff and now it runs worse

Adding an Inline Filter or some additional Fuel Line to allow you to leave the Tank hooked-up for Tuning and Tweaking means having Fuel Line that can easily kink.

The easiest way to prevent the Fuel Line from bending is to fabricate a wire form and attach it to the Fuel Line.

Tape the ends of the "Coat-Hanger" Form to the Fuel Line.
Wrap the works with "Spiral Cable Wrap".
It won't kink and you can still have the Filters and extra length without kinking the line.

 

Re: Fixed some stuff and now it runs worse

Right about the choke on and running good. When you push that choke all the way up when the bike is running... if the carbs are nice and clean and tuned right, it should cause the engine to die.
I know it sucks and nobody loves the heck out of doing carbs... (especially 4 of them) but ya just gotta!
Good luck.
Change those plugs again when you are done.

And then i read your last post here and realized you just said you might have found the problem.
Haha.
How 'bout them Packers! Haha

 

Re: Fixed some stuff and now it runs worse

I am stupid........Went out this morning (it was 20 something degrees mind you), closed the choke about 3/4 and pushed the start button. It fired up in less than a second. It then idled nice and high and I left it there for a minute or two. I then took the choke off completely. It idled just fine although it sounded a little low. It seems good but I can't test ride it safely just yet, I have to finish installing my new brake lines. As much as I would love to, riding with just rear brakes is not exactly my idea of fun (although I may have ridden worse when I was a kid).

Good call on the coat hanger Rick. I have to work tonight and the next few nights but I will try that when I have some time.

Thanks for the input guys, I hoped when I got this bike, I could find a site with people as helpful as the ones on Viragotechforum.com (used to have an 83 920). Turns out XJbikes.com is better! Awesome site!

 

Re: Fixed some stuff and now it runs worse

Rick, you should compile all these little tips into a book

You have way too many good little ideas running through your noggin