a few weeks ago a took the carburetors apart, cleaned them and put it all back together again. It started right up but idled at about 4500. so I took the bike back apart to see if I had a bad seal somewhere. at the same time I reset my air mix screw because I figure its one of those two things thats making it idle high. well its all back together now but it won't start!
I'm sure of my seals, they are tight. i'm getting gas out of the carburetor, my battery is good, I looked at the spark plugs and they were black (one had a little reddish tint ??) but didn't look carbon fouled I whiped them down and although its my first time looking at plugs I didn't see anything that would prevent them from sparking and the floats are working. I tightened the air mix screws and backed them out 4 turns each. I'm a little concerned I over tightened them when I did it. What do I do if I over tightened before backing out? can someone please also explain to me how to ground the spark plug so I can see if I have a good spark? any other ideas as to why it won't start? any and all help is very much appreciated!
thank you!
To ground the spark plugs just touch them against the engine. I think your bike not starting is due to the spark plugs being dirty clean them with a wire brush or better just to change them.
I think your bike is either running very rich or there is a problem with the electrical system not sparking every time they should.
When testing for a spark don't remove the originals from the engine incase petrol escapes from the engine risking a fire, use another spark plug.
just to clarify...so when checking for a spark, you can leave your current spark plugs in and just use another one (like your old ones) to ground to the engine? sounds almost too easy... :)
Unfortunitly carbs are not my strong point, but I think you should be about 3 turns out, and I'm not sure about the overtighten part. Sorry I'm at work and dont have my book. Were are the carb pro's? I'm sure somebody will be along soon. :cheers:
Sounds to me like you were running way rich and fouled the plugs. Try checking your float height (http://www.gstwin.com/float_height_check.htm) and replacing your plugs.
4 turns out is way too much for a stock bike. Try 2.5 and see if it helps. That might not be your only problem but at least it's a place to start.
-M
well thanks everyone for your ideas, it turns out I'm an idiot and forgot to turn the fuel valve on the tank back to the on position. I'm retarded.... what can I say.
so now that I have it started I need high idle advice!
with the air mix scews tightened all the way and the idle screw all the way out and the choke off, the bike still idles at 4000 rpms. This is a cold engine although it has been sitting in the sun (forcast today is high 80's). I think the choke works because when I engage it the rpm's spike and then drop when I close it. I don't think there is false or bad air getting in at the boots or airbox because I just finished tightening everything up and I think I did a decent job and I have a good throttle respnse when I close the throttle the rpm's respond well.
The previous owner rejetted and the main jet is 122, and one of the other two (I couldn't tell which without opening it back up and I'd prefer not to do that, but I will if someone says it would really help) is 45. I couldn't read the third one.
thank you very much for your help.
Dave
Sorry about this I think my last post belongs in a separate thread.
thanks
Quote from: dchrist on August 12, 2006, 11:49:25 AM
Sorry about this I think my last post belongs in a separate thread.
thanks
did you check your float height?
yes I did. thanks for the suggestions. The float hight is good