Sluggish! After a move...

[Ender]

Hey there fellas,
I have a 1981 xs 650. I recently moved to Augusta GA from Denver CO. My bike has been in storage for 3 months. In Denver my bike ran fine, tip top. Since I got here all Ive done is put new oil in and fill it up with gas. I took out for a spin to today and was appalled at how it was running..like it had now power at all very sluggish especially in the first three gears. I did use a different oil than I usually use because I can not find it here could that be the cause? I would appreciate any feed back or ideas on what could be going on..Thanks..

 

[Travis]

Mile high city. Less dense air there. Maybe try re-jetting, you might be lean. Either that or your gas went bad and plugged up your carbs. How does it idle?

 

[bdholsin]

20W50 oil (rated for bikes) should be your chioce.

Otherwise you may need to take a look at your jets with the altitude change. Going to a lower altitude as you have done may require different (possibly bigger) jets as the air is more dense and you're running leaner.

Is it popping or backfiring? If so, where...carbs, exhaust?

Also, double check your valve clearances. The altitude change may have uncovered the valves being out of spec a bit. As a matter of fact this is the first thing I would suggest as it should be done from time to time.

 

[Ender]

I messed the jetting at first to get it to quit back firing and get a good idle...but there is just no power at all..Im worried something big went haywire

 

[bdholsin]

I messed the jetting at first to get it to quit back firing and get a good idle...but there is just no power at all..Im worried something big went haywire

Take a step back. You're good. She's running...just not breathing from the sounds of it. Reset your idle mix screws too.

If it is still showing these symptoms then I'd clean the carbs, clean the carbs and finally clean the carbs.

Are you running with a fuel filter at all?

 

[Ender]

It was backfiring from the exhaust

 

[Travis]

What do you mean messed with the jetting? What was in there and what did you change them to?

 

[Ender]

Yeah I have two inline fuel filters on going to each carb

 

[Ender]

not jetting..my bad idle mixture screws

 

[Travis]

If it ran like a champ before the move, and all you did was change the oil and add gas, I'd look into the carbs some more. Pull them, clean them, check the float heights, check what jetting you currently have in there for future reference, then put them back on and check for air leaks, set the mixture screws, sync them, and see how she runs.

 

[Ender]

All right..sounds good. I'll giver a shot and see what happens..thanks

 

[YOURADHERE]

If it was running fine pre-move then it's definately your jetting. You went from ~10,000ft about sea level to ~sea level. The air in Denver is less dense so to adjust to the new climate in Georgia you'll have to rejet. Since it's backfiring(likely on decel) then that means your mixture is lean(needs more fuel). Put the idle/mixture screw back as it was and go up on your main jet a size at a time and see where that gets you.

 

[bdholsin]

If it was running fine pre-move then it's definately your jetting. You went from ~10,000ft about sea level to ~sea level. The air in Denver is less dense so to adjust to the new climate in Georgia you'll have to rejet. Since it's backfiring(likely on decel) then that means your mixture is lean(needs more fuel). Put the idle/mixture screw back as it was and go up on your main jet a size at a time and see where that gets you.

I was under the impression that backfiring out the exhaust was running rich (I recently went through this). Yeah, he needs to look into the idle mix screws and reset (suggest using the dead cylinder method) to what works.

 

[YOURADHERE]

I was under the impression that backfiring out the exhaust was running rich (I recently went through this). Yeah, he needs to look into the idle mix screws and reset (suggest using the dead cylinder method) to what works.

I could be wrong but Ive always been told popping= Lean, and bogging/sputtering/black smoke = Rich

 

[bdholsin]

My backfiring through the exhaust was because I had overjetted. I guess the best way to tell is read the plugs.

 

[jamesgs4]

If it was running fine pre-move then it's definately your jetting. You went from ~10,000ft about sea level to ~sea level. The air in Denver is less dense so to adjust to the new climate in Georgia you'll have to rejet. Since it's backfiring(likely on decel) then that means your mixture is lean(needs more fuel). Put the idle/mixture screw back as it was and go up on your main jet a size at a time and see where that gets you.

lol we aint that high in denver!

 

[Travis]

Yeah it's not two mile high city

 

[YOURADHERE]

Whatever guy Either way your jetting is off for your current location.

 

[xjwmx]

CV carbs like the '81 stock carb are self-altitude compensating for mixture