low idle speed need help

my idle speed is about 500 after the SW is at running temp. why would it be this low the SW does not cut off and seem to ride just fine but after reading the owner's manual i know it need to be somewhere near 1200. what can i do to get the idle speed up without adjusting the idle speed? if something need to be fixed i would prefer to do that before I adjust the idle speed.

Year of bike? Mileage? Without this info it's really difficult to make a diagnosis. Any parts replaced, such as spark plugs or air filter? Any mods done to the engine or electrical system? I have suggestions, but need this info first.

it's a 2002 SW that i just got a week or so ago it has 14,987 miles on it. cant say if the air filter or plug has been replaced or not as far as i know it has no mobs done to the engine. electrical system it has a J&M CB radio installed it also has Gerbing 12V Permanent Dual Temp Controller

You are ready for a belt change at 16000 miles.

So if you are of the DIY persuasion then you can order one now along with a new air filter. Meanwhile you might want to adjust the warmed up engine idle with the phillips head idle screw located beneath the round hole in the underseat cover. You'll have to move aside some vacuum hoses to see that phillips head screw. Do not mistake that idle adjustment for the air adjustment screws. Later after you've replaced the air filter you may need to tweak the air adjustment screws. They are at the throttle bodies in that same cluster of vacuum hoses and are brass slot head screws. You'll need to remove that underseat cover and use a manometer to balance those air adjustment screws. Check elsewhere on this forum for links to DIY manometer. Inexpensive and easy to put together using clear plastic tubing, some vacuum connectors, a piece of 2X3, and a ruler. HTH

Tim

I would be interested in the DIY manometer but the pictures seem to have been removed from the OP. Any chance they could be reposted?

Based on your description of the idle, there is a drastic issue, either with throttle plate synchronization or idle speed adjustment, or both. Maybe a previous owner was screwing around and really messed it up.
Based on the age and mileage of your bike, another issue you could have is a low idle caused by an overly rich mixture. The fuel pressure regulator could have a pinhole leak, allowing extra fuel into the intake through the vacuum hoses. To check for this issue, first pull the spark plugs. If they're black and wet, look at the fuel pressure regulator. Another giveaway to that problem is evidence of raw fuel in the vacuum lines running to the intake manifold. If any of those vacuum lines contains gasoline, you have a fuel pressure regulator issue.

This is the vacuum gauge I use, but in the 2 cylinder model.

http://www.carbtune.com/carbaccs.html

Belt and rollers already in the mail   i will order a new air and oil filter today the bike had a new plug under the seat and i will replace that today. thanks so much for the help guys

ericclapham wrote:

I would be interested in the DIY manometer but the pictures seem to have been removed from the OP. Any chance they could be reposted?

Here is a link to a DIY Manometer. It's the same pattern I used. Except I used shock oil in the tube, rather than water, so that it was more visible and glued a paper IKEA ruler between the tubes to "measure" the vacuum difference. HTH
http://www.obairlann.net/reaper/motorcycle/manometer.html

Tim

You will need two new plugs, so if you found one you need a mate for it.

Thanks CJ.That article is very precise. I guess you could tint the H2O with food dye to make it more visible.

ericclapham wrote:

Thanks CJ.That article is very precise. I guess you could tint the H2O with food dye to make it more visible.

Yes, you could use tinted water, but I thought a thin oil-based medium would be less damaging than water if it should accidentally get sucked into the engine. Also, the oil will give a more dampened reading.

The vacuum tubes on the SW have a 3.5MM I.D. So don't use the 1/4 tubing which the article calls for. 3.5MM = ~9/64" while 1/4"= 6.35MM, I used 1/8" tubing purchased at the local Home Depot big box home supply store. 1/8" = 3.1MM. That said, if you only have 1/4" tubing available then maybe you can figure out how to reduce the ends down to 3.5 MM to fit the vacuum stubs.

You'll probably want to construct your manometer several days in advance to allow all the air bubbles to migrate out and the oil to balance. Setting it vertically with the lose hoses above the device itself helps with those air bubbles --but it seems to take forever.

Tim

Try some aquarium aerator hose it might be a good fit. Its also fit on a 3 oz s bottle to lube the diff.