Hi there
Recently I purchased a 1992 Yamaha xtz 750 for I think a decent price for getting in the adv . I know might be maybe just a middlife crises and one more project what might not get finished but we all been there " the price was too good " .
So bike started but runned just with choke pulled . Didn't wanna force it and I bought couple of new things.
Needles looked almost new changed the tubes in witch the needle slides .... New rubber that connects carb to engine
New fuel pump . The cables run fine and when I pull the gas gets back nice. Took it to mechanic ( got robbed) he did a sync on them.
The problem.
Happens often the rpm won't drop to idle when I stop or slow down a lot ... Stays in the 3000 and I'm not able to sift back in second gear smoothly.
If I rev the bike sometimes gets back normally but mostly no.
What u guys suggest? Thank you.
If there anyway I can post a vid I will.
I'm new here and pls excuse my english

Assuming issue not with carbs, check the following

Air filter not blocked
All rubber hoses(especially carb to engine) ...looking for leaks
Throttle or choke cable sticking

Hi Hawk.
Well I tried to run it without airbox as well same issue.
The rubber that connects carb to engine are new.
Cables looks tight and responsive.
Sometimes if I rev couple. Of times more gets back to 1200.
If sticks to 3000 andl I lift the vacuum film piston with my fingers it gets back to 1200.
Thx.

http://www.factorypro.com/tech_tuning_p ... gines.html

Found these pages useful in the past. They do the high and low rpm pages.
But I’d disconnect the cables, check moving parts don’t sticks open by hand with engine off.
Check choke shuts off. Then look at carb settings and levels etc.