XJ700X sync

[dannymax]

Been fighting a hanging idle for quite awhile on this bike, the other day, after a water pump rebuild and float level check it started 'hunting' for idle....would idle smoothly for a minute or so, then jump to 2100 for 15 - 20 seconds and drop back to idle.

A guy on the XJ forum said it was a sync problem....'it's close but not close enough'. I was real skeptical about that but hooked the Carbtune up anyway....one of the center cylinders was a couple lines off so I dialed it back in and sure enough....it felt and sounded like a different motor. Idles smoothly with no change in rpms, snappy off idle....sounds like it did when I drove it away from the dealers....29 years ago!

I never would have thought that tiny a change would make THAT much difference. Guess these little motors are 'zero tolerance sync', it's either perfect, or it's wrong!

 

[tothemax93]

And your just the man for that job, being the synco-holic that you are :eusa_dance:

 

[sdt354]

Glad to hear that little jewel is running as sweet as it looks Dann-o.

 

[johnpclynch]

And your just the man for that job, being the synco-holic that you are :eusa_dance:

Sounds like you might have invented a new award :biglaugh:

 

[one2dmax]

Looking nice and even for sure. Now to get ready for the 1000cc conversion on the little beast.

 

[gamorg02]

danny when you say a 'couple lines' you mean the small ones or the big ones?

 

[dannymax]

"Hi, my name is Danny....I have this problem......." :biglaugh:

At 90 hp and about 550# (I think) she doesn't embarrass ya any, but 1K would be some kick, eh? :rocket bike:

Garrett....two little lines, the ones that Carbtune says if you are within it's a good sync. The VMax is much more forgiving

 

[gamorg02]

"Hi, my name is Danny....I have this problem......." :biglaugh:

At 90 hp and about 550# (I think) she doesn't embarrass ya any, but 1K would be some kick, eh? :rocket bike:

Garrett....two little lines, the ones that Carbtune says if you are within it's a good sync. The VMax is much more forgiving

jezus that aint much at all. thinking from my motion pro it waivers at least that much just sitting there:

 

[dannymax]

jezus that aint much at all. thinking from my motion pro it waivers at least that much just sitting there:

No, it isn't much at all....and to make such a huge difference! Can't say I understand how being slightly out of sync will cause it to 'hunt' for idle....or hang the idle for that matter......:confused2::ummm::confused2:

Not at all normal like a VMax! :biglaugh: