Hanging throttle/Slow idle return? (Video)

[Pio412]

Greetings fellow riders. I appreciate all the help from before about my starter issue. Now we have more adventures to conquer.... It's seems to have a hanging throttle and some popping. Not sure what could cause this. Could it be a bad sync? Vacuum leak? Anything else?. Before I dive in again I'd love to hear everyone's thoughts... I attached a video so you can hear and diagnose. Cheers

[Acton67]

If I were having this issue I'd consider what work was recently done on the bike. Anything related to the carbs? Did you adjust the throttle cables at all recently?

I had a similar issue last year and the housing for the throttle cable coming out of the splitter to the throttle was damaged and getting hung up on the outer lip of the hole where the throttle cable housing inserts into the splitter. This was causing obvious issues at idle with my rpms being way to high. I kept trying to adjust the carbs until I finally figured out the issue.

Your issue is probably related to something different but the point is that it's important to do some detective work, what recent work did you do on the bike that could have caused this?

Also nothing wrong with cleaning the carbs and the fuel pump out, I threw inline fuel filters on my bike before and after the fuel pump, no issues since then. I resynchd the carbs too and adjusted the idle/fuel mixture screws too. Sometimes the shotgun approach does the trick.

I'm still a novice, I'm sure others with more experience will chime in but that's my two cents for what they're worth.

[sgtcall]

See above for good recommendations.

If you want to start with something easy and part of routine maintenance anyway try lubing the throttle cable. If you have the OEM wire you can use household oil, WD40, or something like liquid wrench. If you have an aftermarket nylon cable you would have to use something safe for plastics, silicone based.

Just disconnect at the top of the throttle and drip some down the wire while working it a bit. Then reattach the cable.

[Pio412]

Thanks for the replies. Nothing has been done to this other than me cleaning the carbs, putting a new battery in and starter. As well as plugs. Never touched the throttle cables...cleaned carbs while still having cables attached without messing with sync. I'll look into what you've suggested acton67. Going to have to dig back into it.

[hillsy v2]

...cleaned carbs while still having cables attached without messing with sync.

If you removed the carbs even with the cables attached they are more than likely out of sync now.

[Acton67]

...cleaned carbs while still having cables attached without messing with sync.

If you removed the carbs even with the cables attached they are more than likely out of sync now.

^This. I cleaned my carbs last year without removing the cables from the carbs and I still had to resynch afterwards. Kudos on detaching the carbs without removing the cables from the carbs though, I see plenty of guys on YouTube struggle to remove the cables off the carbs while they're still on the bike when thats completely unnecessary. But that means you must've detached them from the splitter, or removed the whole throttle cable assembly splitter and all from the bike which could still cause an issue at the splitter..

The way you routed the cables could also be an issue. I remember I had to look at the Clymer manual to determine what order to route what first over the front airbox. I can't remember if the splitter went first then the clutch cable or the other way around, then the wiring harness last. I do remember the throttle cable had issues if if wasn't routed correctly though. Space is kinda tight there since everything gets routed under the tank bracket that sits over the front airbox.

[FallenAngel]

Greetings fellow riders. I appreciate all the help from before about my starter issue. Now we have more adventures to conquer.... It's seems to have a hanging throttle and some popping. Not sure what could cause this. Could it be a bad sync? Vacuum leak? Anything else?. Before I dive in again I'd love to hear everyone's thoughts... I attached a video so you can hear and diagnose. Cheers

I would agree with SgtCall and Hillsy V 2.0
Your cables may have stretched over time and even though the bike ran OK in the past it still could have been just a little out of sync.
Also as you mentioned you could have a vacuum leak Maybe even both
I use an old oxyweld torch tip on a propane bottle to check for vacuum leaks*with the bike running turn the gas on ,dont light it. then move the tip around the manifold and carbs when the engine smooths out you found your leak. Much safer then carb clean.
but it sounds more like a sync problem

[Lechy]

Make sure that the boot from airbox to carb is fully seated, the rear is a real bitch to get on the airbox. It helps to remove the 3 fasteners from the top of the airbox to give a little wiggle room, one of these is a great help to seat the boot:


Next would be a synch and AF adjutment.
Get someone to operate the throttle and observe the chrome butterfly actuators to see if they are returning correctly and fully closing (as mentioned before to ensure that the cables are moving freely in the sleeves).

[Henchman]

I'd check cable routing for sure. And check the carb to rubber intake and air box connections. They are horrible to get back in place. I had to replace both rubber intakes. Mine was popping on acceleration and deceleration. The intakes looked good until I took them off and sure enough they hade cracks.

Was the motor fully harmed? Looks like the choke was still pulled in the vid

[Pio412]

Hi everyone sorry for the late reply, finaly got some time to work in the garage... I got it running silky smooth now! (after i synced the carbs) the slow drop to idle was the issue of the idle being set too high. So I synced the carbs at first with a cheap $25 pair of generic gauges from amazon... didn't work.. junk...couldn't get an accurate reading at the throttle set screw adjustment. So I went and tried the ALPHA MOTO Carb Sync (link below) and they work fantastic! kit comes with everything you need and i managed to get the idle and throttle sync perfect with these. Now i just need to adjust the mixture screws accordingly. I just about got it dialed in.