Oil Change.... Now Low Idle! almost stalling wtf!

[santorini]

i treated my baby to an oil change - to Motul 20w50 mineral Oil. and a Hi-Flo filter.

Took my time and I have changed oil many times before on bikes so I did it properly.

After oil change bike idle seems lower! I think it was 1100rpm or so when warm before.. now it is a solid 900rpm and when cold bike almost stalls sometimes.

When I first start the bike in the morning (even with cold start lever on), at first battery light is even on, as revs low and I have to rev the bike a bit to get that light to go off.

I did wash the bike after, but literally by hand with a a wet cloth and not too much water.

What would cause the idle to suddenly drop 200rpm after this repair session?

[ckcarr]

Took my time and I have changed oil many times before on bikes so I did it properly.

Maybe...


How much oil came out, and how much did you put in? What is the oil level in the sight glass when you hold the bike level?

Generally, over the years it seems that new owners (and old ones too) will do other things when they say that they only did this one thing. If you re-think what steps you performed, what else might you have touched?

[santorini]

i didn't measure old oil coming out but level was normal - full sight glass before changing.

after I put in 3.75L and sight glass is bang on - at half way mark when bike upright.

There was only 2 things to unscrew so that's all I touched during oil change

[RIQUE]

I see no reason why changing oil would affect your idle to the worse. Maybe during the change you moved the accelerator cable of its support base near the throttle body.

[SergioK]

It wasn't the oil change but the bike wash that did it. If the idle is erratic at all check the throttle cable sheaths at the TBs.

[Cruzer]

Had it happen too after a wash.

[twodear]

The alternator light staying on until blipping the throttle is fairly normal. I'd turned a wrecked bike into a track-day rider and took time to reduce the wiring harness to the bare essentials. I was happy that the bike actually started and ran fine afterwards with the exception of the alternator not charging the battery. I followed the wiring diagram through again and again but found nothing. I finally broke down to take it to an automotive electrics shop and all he did was to make a jumper wire from the output of the alternator to another connection on the back of the alternator. Apparently the alternator needs a kick before it will start charging. Blipping the throttle and the resulting bit of volts to the exciter coil is what gives that kick.

Regarding the low idle, I would agree that washing the bike resulted in a cable or adjustment being moved.

[santorini]

good advice guys - will check tomorrow