Cold # 2 @ idle

[ErnieGS1100EZ]

Hello all,
I know this topic has been discussed before so the board police has the right to be mad at me but here goes.

Over the weekend I checked on my son's & I's GS1100EZ project after he got home and #2 header was cold with the bike warmed up. I read in the forum that it could be the fuel petcock so I removed the tank and put on the aux tank and plugged the vacuum line to #2. Started the bike and it ran good except 2 was cold. My guess is that it is not the petcock. I took the bike for a ride and the exhaust gets hot when the motor get's around 3000 rpm. The motor sounds different too. I wonder if that's when the carb starts to work.

I don't have any experience with 16 valve engines but could there be a possible exhaust valve lifting on 2?


Thanks in advance.

Ernie

[Guest]

First check the spark plug and connection. If you have never done a valve clearance on this engine do it. The sixteen valve motors are very easy to do.
Did you plug the vacuum line on #2 and is the vacuum line good?
If you need to do a valve clearance synchronize the carbs afterwards.

[49er]

Hello all,
I know this topic has been discussed before so the board police has the right to be mad at me but here goes.

Over the weekend I checked on my son's & I's GS1100EZ project after he got home and #2 header was cold with the bike warmed up. I read in the forum that it could be the fuel petcock so I removed the tank and put on the aux tank and plugged the vacuum line to #2. Started the bike and it ran good except 2 was cold. My guess is that it is not the petcock. I took the bike for a ride and the exhaust gets hot when the motor get's around 3000 rpm. The motor sounds different too. I wonder if that's when the carb starts to work.

I don't have any experience with 16 valve engines but could there be a possible exhaust valve lifting on 2?


Thanks in advance.

Ernie

Being a project, I gather the bike has sat without running for a period. Sounds like your pilot circuit on #2 carb is partially/completely blocked. Take the carbs off the bike. Dissassemble them and give them a good soaking in carb cleaner. Use compressed air to blow out all the galley passages before re-installing the jets. On the really small passages you can carefully use fine wire to poke out any stubborn particles followed by compressed air. Check the condition of the gaskets, float needles and replace the O rings.
There is a link somewhere on this site that details the proceedure for overhauling your CV carbs. Check it out.

[mortation]

1) Check the wire and make sure it sparks!
2) Check the plug, is it wet? Dry? Color? Is it new?
3) Check your boots/O-Rings. A big air leak can cause similar issues.

[ErnieGS1100EZ]

Hi guys,
The bike was bought after it sat for awhile. The carb (4) rebuild was the first thing we did. The spark plug is firing but it looks sootier than the others. All replaced when we first fired it up. Hum, maybe something here. I replaced the vacuum line and plugged it for the test.
I sprayed starting fluid all around the carbs and intakes and no difference in the rpms. The boots came off easily. There weren't any cracks on them.
One thing I forgot to mention is that sometimes the rpms go to 3000 for no reason. I sincronized the carbs at 1500 rpms. Should I have done it at a different rpm?
The bike has 37k on it. I never valve cover off so I guess it's time......
Thanks

[mortation]

Hi guys,
The bike was bought after it sat for awhile. The carb (4) rebuild was the first thing we did. The spark plug is firing but it looks sootier than the others. All replaced when we first fired it up. Hum, maybe something here. I replaced the vacuum line and plugged it for the test.
I sprayed starting fluid all around the carbs and intakes and no difference in the rpms. The boots came off easily. There weren't any cracks on them.
One thing I forgot to mention is that sometimes the rpms go to 3000 for no reason. I sincronized the carbs at 1500 rpms. Should I have done it at a different rpm?
The bike has 37k on it. I never valve cover off so I guess it's time......
Thanks

I think the Z is 82 and therefore should be around 1000 - 1200 RPMS I think.
The plug is sooty? Clean it and then do a reading after letting it idle.

When you rebuilt the carbs did you replace ALL the O-Rings & Gaskets? Did you follow the carb doc here? When you put the boots on did you replace the boot O rings? Make sure you clamp the fuel and vacuum lines when connected properly to prevent any leaks.

[ErnieGS1100EZ]

Boot "O" rings????

[smagnusen]

Not hijacking here but would like to tack on my current similar problem. I've got a cold #3 at idle but it heats up quickly past the idle circuit. I've done boots, o-rings, a thorough carb-dip and cleaning, checked the float levels, valves, and a performed a good carb sync. I've got a good spark and compression. It's a real head scratcher. Curious what develops here. If I figure out my problem before you I'll be sure to post it.

[Farmer]

1981 850G Cold Pipe, #2

Similar frustration...bought the bike three years ago. Runs great at 70, but misses at low rpm..below 3500 RPM. I used to have a cold three exhaust...repaced the coils..wires...plugs. No help. After reading hours in this forum, I decided that I needed to check the valve clearances...sure enough they were all too tight. I needed to go from 2.70 to 2.60 or 10mm thinner shimms on all of the valves.

And I bought new carbs on ebay, rebuilt them with new o rings etc. put her all back together and she started and idled better than she ever had...but not too fast. Now the number 2 cylinder is not firing at idle...cold pipe. Has good spark.. and it is not the fuel valve. I replaced the intake O rings and boots last year.

Since I had an extra # 2 Carb...the ones I used before ebay...I tried that...still no joy. Compression about 100 at idle 130 at rpm. A little low, but it ran hot before all of this. If I figure it out, I will let you know.

[Farmer]

Took off the tank, air box, carbs. Installed the manometer connectons to the boots with the carbs off. Put the carbs, airbox back on, ran and synced with an aux tank. Seems the actual vacumm sync cured the number two cold pipe. Bottom line so far... Start with a valve adjustment...then manual sync, then manometer sync. I took off the lock nuts on the throttle plate adjustments and use lock tight #2..green. Trying to install Vance & Hines 4 into 1 exhaust. Twisted off three exhaust manifold bolts..it never ends...more to follow