Hey guys.
I got my bike recently with slight starting trouble the day I bought it (owner admitted he had to prime it via the carb holder inlets to get it started). Drove it home and it drove relatively well (intitial idle was a bit rough, but appered to even out as time went on during the trip home). Oil was leaking out the air intake when I got it home and I discovered the oil was overfilled (has since been drained/corrected).
Put it new plugs. Didn't start.
Tried to prime as suggested by the previous owner. Didn't start.
It DOES turn over well (not weak).
There IS spark on all plugs. (Although maybe not the strongest...I don't have much basis for comparison though)
The bike had been in storage, but the owner said he rebuilt the carbs. I wasn't sure if he had done a good job, so I did it myself, but they were perfectly clean. I've also drained the old fuel and put in fresh premium (which is flowing into the float bowls)
Still no go. Any sugggestions?
Thanks.
sortof starts: 82 maxim 550
sortof starts: 82 maxim 550
Last edited by maximnewb on Wed Aug 03, 2005 2:04 pm, edited 1 time in total.
-
TechTMW
- Legendary 2000
- Posts: 2045
- Joined: Fri Mar 19, 2004 12:43 pm
- Sex: Male
- Years Riding: 10
- My Motorcycle: 2005 BMW R1200GS
- Location: Alexandria VA
You know the bike best at this point.
I always beat my head against the wall with problems like this, then leave it for a while and when I come back it's something obvious.
Just make sure everythiong's set up correctly, and make sure the idle air passages aren't pooched. Just because the jesta nd stuff are clean doesn't mean that the whole carb is (and that's what your initial problem sounded like to me)
I always beat my head against the wall with problems like this, then leave it for a while and when I come back it's something obvious.
Just make sure everythiong's set up correctly, and make sure the idle air passages aren't pooched. Just because the jesta nd stuff are clean doesn't mean that the whole carb is (and that's what your initial problem sounded like to me)
“People demand freedom of speech as a compensation for the freedom of thought which they seldom use.”
- Soren Kierkegaard (19th century Danish philosopher)
- Soren Kierkegaard (19th century Danish philosopher)
-
TechTMW
- Legendary 2000
- Posts: 2045
- Joined: Fri Mar 19, 2004 12:43 pm
- Sex: Male
- Years Riding: 10
- My Motorcycle: 2005 BMW R1200GS
- Location: Alexandria VA
Haha ok, now we're getting somewhere.
Try your idle screw adjustment first - it's an obvious culprit. I only have a manual for the xj650/750 so I can't tell you what the factory steup is ... just close it down all the way then back it off about a turn. Make fine adjustments (1/4 turn increments) from there.
Let us know if that works. (If it doesn't work, your pilot/idle circuit is still dirty in the carbs)
Try your idle screw adjustment first - it's an obvious culprit. I only have a manual for the xj650/750 so I can't tell you what the factory steup is ... just close it down all the way then back it off about a turn. Make fine adjustments (1/4 turn increments) from there.
Let us know if that works. (If it doesn't work, your pilot/idle circuit is still dirty in the carbs)
“People demand freedom of speech as a compensation for the freedom of thought which they seldom use.”
- Soren Kierkegaard (19th century Danish philosopher)
- Soren Kierkegaard (19th century Danish philosopher)
Thanks again for the replies. I appreciate the help.
I have a CD manual for my bike so I'm sure I can figure out the idle screw adjustments. I'll give that a whirl and see what happens.
But I'm almost 100% sure the idle air passage is clean as a whistle...unless I got my terminology wrong and I'm thinking of another passage. There was essentially NO buildup in the carbs at all, however, there's a good chance they're out of sync, which may be causing the rough idle. I don't really know much about carb troubleshooting though.
Do you think it's worthwhile trying to find a cheap(er) vacuum gauge and try sync them myself? I'm have no idea what a shop would charge for this kind of work (or how tricky of a process it is).
I have a CD manual for my bike so I'm sure I can figure out the idle screw adjustments. I'll give that a whirl and see what happens.
But I'm almost 100% sure the idle air passage is clean as a whistle...unless I got my terminology wrong and I'm thinking of another passage. There was essentially NO buildup in the carbs at all, however, there's a good chance they're out of sync, which may be causing the rough idle. I don't really know much about carb troubleshooting though.
Do you think it's worthwhile trying to find a cheap(er) vacuum gauge and try sync them myself? I'm have no idea what a shop would charge for this kind of work (or how tricky of a process it is).
When you are trying to start it, touch each of the pipes, and see if any of them are warming up, or more to the point, not warming up. That will tell you which cylinders it is not firing on.
A little trick I have just learnt.... lift the tank or whatever you have to do to get access to the sparkplugs, with the tank still attached so you get fuel to the carbs. Using a pair of insulated pliers, lift the HT lead off the plug, and vary the distance away from the plug while cranking the motor, or while the motor is running, if it is not firing on that cylinder. For some reason, when the spark has to jump from the HT cap to the plug, it seems to increase the amount of spark going through the plug, and can result in the bike firing on that cylinder. Be careful not to touch the HT cap when you do this though, else it will zap you big time!
I have to do this with my CBR, as it has been sitting while I have been rebuilding it. Once it has run for a while, firing on all after doing the HT thing, it seems to be much better and starts with no problems.
Another thing to check is the float levels in your carbs. Poss too high, so the fuel is wetting the plugs?
Hope this helps, let us know!
S
A little trick I have just learnt.... lift the tank or whatever you have to do to get access to the sparkplugs, with the tank still attached so you get fuel to the carbs. Using a pair of insulated pliers, lift the HT lead off the plug, and vary the distance away from the plug while cranking the motor, or while the motor is running, if it is not firing on that cylinder. For some reason, when the spark has to jump from the HT cap to the plug, it seems to increase the amount of spark going through the plug, and can result in the bike firing on that cylinder. Be careful not to touch the HT cap when you do this though, else it will zap you big time!
I have to do this with my CBR, as it has been sitting while I have been rebuilding it. Once it has run for a while, firing on all after doing the HT thing, it seems to be much better and starts with no problems.
Another thing to check is the float levels in your carbs. Poss too high, so the fuel is wetting the plugs?
Hope this helps, let us know!
S
that's my 2 cents worth.....
