GS500 -03 - was running great, now wont start!!

[puffbrother]

Hello everyone, I am new to this forum, and fairly new to bikes.

About a couple months ago I invested in a GS500 03 model, and its so much fun!!
It is my first bike, but I kind of know my way around with tools and what not.

Had to do a service a couple of weeks ago, change the oil and oil filter. Changed the sparks. Gave carbie a rough clean.
And it all seemed good. I put the bike together and it started fine, but did not run fine.
So I pulled it all a part again, to find one of the houses running betwen the carbie and petcock had a tiny hole to it.
I ended up replacing the hose, and made sure all others ran fine.
After that it seemed to be running like a charm again! Was so enjoyable!

But then!! The other night, I had to ride to the shop, rode there and back without any dramas. But bike backfired once or twice. Didnt think much of it at the time.
Then the morning after, I went to ride my bike to work. Which I do everyday without dramas! But this time the bastard did not wanna kick over! I tried few different things - put it on res, pri, on. adjusted idle. tried with choke/without. after a little bit it finally kicked over. But then it ran like crap. Now it wont go over 6000rpm, and once getting close too it (around 5000-5500) it starts to shug, backfire, and in basics being a real Buddha Loves You to me!
Rode it to work tho, going easy. Had troubles starting it whilst heading home too, and ran like crap...
This morning it just wouldnt start at all.. I cleaned the sparks quickly, but seems like no spark or little spark..

Not sure what the problem might be. but some help with troubleshooting would be nice!! THANKS IN ADVANCE!

[EdChen]

How did the spark plugs look? You need air, fuel and spark to run. I'd do some simple tests confirming that they're sparking. Then check that fuel is getting through the petcocks. Since you had the carbs out, I'd make sure that none of your lines are crossed, both the vacuum lines and fuel lines.

[Big Rich]

By chance, does the bike have the original battery?

[puffbrother]

So I have tried to work out the problem over the weekend, and with no luck.

I pulled the carbie out again and gave it a clean. The sparks are looking ok, but a little black. Do you think the new sparks I put in, already have shat themselves?
I also clean petcocks and check all the hoses. Would a crossed hose give the bellow problems?

It seems to be starting up a little better then it did before, but I still have the problem where - when I  reached 5500-6000rpm it starts bogging out.
Even just sitting in neutral, I try to rev it as much as I can (even though its bad) but as I hit the 6000 mark it starts jumping between 2000 and 6000rpm with occasional back fire.

Also battery levels look good, but I did have to jump start it the other day to get him running (after sitting for a couple of days while I cleaned the fuel system)

I am planning on, whilst going easy, driving it to work and on my way stop by a mechanic to get some opinions on what it might be.
Cause I am soooo confused towards what the problem might be

Thanks you mob who are trying to help

[Big Rich]

I'm still going with a weak battery..... you never did say if it was original.

Black spark plugs mean a rich condition, but that could be caused by a number of things. What is the voltage at the terminals with ignition off, ignition on, running at idle, and running around 5k rpm?

[bombsquad83]

I'm guessing it's a fuel overfilling the bowls problem.  I had similar issues with my bike when I bought it.  Once I did a very thorough carb clean and got new OEM needle valve sets and adjusted the float height, all was solved. 

I also replaced the vacuum petcock with a non-vacuum one and capped off the vacuum port.  That's probably not necessary for you, but I didn't trust the old fuel exposed diaphragm in the petcock to perform up to the standard required.  It's cheaper to go the non-vacuum route for a new petcock as well.

[puffbrother]

Thanks all.

I am not hundred percent sure whether its an original battery or not. I have only had the bike for a couple of months, and its the same battery as when I bought it (second hand).
I will get my mate to help me check the voltage this afternoon, seeing as he is an electrician and know more about that then me.

I took it past the mechanics on my way to work today. It took me a little bit to get it started, and once it ran it ran like crap again.
However!! I stopped and parked at the mechanics, asked for an opinion. He started it up, saying sounds like a carbie clean is needed. And he rev'd it up, backfired a couple of times and shot up to 11 000 rpm! Just like that, he must have magic hands!!
I am not saying the problem and cause is fixed, but after that I could actually ride it properly.

I joked and said he cleaned it out for me. So it looks like what I might need is a proper, proper clean our of the carbie. And maybe new jets and a proper tune of it.

Will keep all posted how I go with sorting it out thru out the weekend. But planning on taking my CR250 for a bushbash too so see if I get time for both