High Idle - Thottle Cables?

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zippo6

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So I buttoned up the motor last night, new Orings on the elbow and the screw for the stator (timing hole)... anyway I filled coolant and oil, replaced filter (not in that order :rofl_200:) and fired the bike up. I still have a high idle. I can bring the idle down by twisting the throttle backwards, so this leads me to believe it is cable related and I need some adjustment....

Can anyone offer some pointers or recommendations oh how or where I should adjust from? I've looked everything over and can only see one adjust point on 1 cable at the throttle.... am I missing anything?

.... and it's not the idle screw, I backed that way down and if I reach in and push on the (what-ever the hell it's called) bracket that contacts the idle screw I can push it down - basically the same thing twisting the throttle backwards does.
 
Its usually the back right carb screw (if you are sitting on the bike)that needs turning to get the idle to come back down, thats what was holding mine @ about 2K. Really you need a sync tool hooked up to get them back in tune.
 
Its usually the back right carb screw (if you are sitting on the bike)that needs turning to get the idle to come back down, thats what was holding mine @ about 2K. Really you need a sync tool hooked up to get them back in tune.

I have a Morgan CarbTune Pro.... do you really think it's the synch that causing my high idle? When I say high, it was running up to over 4K! I never let it settle, I backed it down myself.
 
Did you have carbs apart ? if not that may not be your problem. but if you can push on the sync bar that ties the two sides together to slow engine down something is out of whack on that side.
 
Did you have carbs apart ? if not that may not be your problem. but if you can push on the sync bar that ties the two sides together to slow engine down something is out of whack on that side.

Oh ya, I had them completely apart for cleaning. I'll hook up my sync tool and give it a try.... I know they are way out of whack, but it never occurred to me that that could actually be the cause.
 
Oh definitely, anytime you unbolt the carb brackets and do a reassemble there is nothing on the brackets to realign carbs back to original position, therefore resych is in order.......
 
The bracket screws are sometimes so tight you have to use an impact driver to get them loose. Hopefully if you used the impact driver you did not have the carb assembly on a hard surface while whacking on the driver, if you did you could have a bent carb bracket throwing sync way out of whack. I always have someone hold the carbs while I whack the driver to prevent bending the mounting brackets.
 
I'm not a big fan of the impact driver on carb racks, the shock can disturb float settings, sync and other stuff. I use an 18V Dewalt cordless and phillips bit....if that mouses the head out then dremel a slot and use a large flat screwdriver and small crescent wrench. Works every time.

Then pitch the oem screws in the shitcan and replace them with allen heads.
 
The bracket screws are sometimes so tight you have to use an impact driver to get them loose. Hopefully if you used the impact driver you did not have the carb assembly on a hard surface while whacking on the driver, if you did you could have a bent carb bracket throwing sync way out of whack. I always have someone hold the carbs while I whack the driver to prevent bending the mounting brackets.

I only used my impact for reassembly (it's cordless, not manual) and I was gentle enough that the impact barely kicked in. I'll try to synch and see what happens. :)
 
You should be OK then, the impact tool Danny and I were referring to is one that you hold in your hand with tool against screw and knock the hell out of the impact tool. It's an old style tool I have had for many years and maybe you have never seen one. Like Danny said, you can knock a lot of things out of whack using this old type impact tool, including your hand should you miss hitting the impact tool with hammer.
 
It sounds like you are talking about a 'cordless screwdriver' for reassembly. If so, those are completely OK. I think what alorio1 is referring to as an 'impact driver' is one that you manually whack with a hammer to loosen those phillips screws the factory always seems to overtighten upon assembly.

If re-synching doesn't get the idle back down, and if your brackets' not bent, you may have gotten the linkages between carb sets back together incorrectly. I've seen that happen a time or two between my Max & Venture carbs over the years. Too easy to overlook while reassembling IMO. Do it once however, and you tend not to overlook again - pulling the carbs back off to fix can be a pain.
 
I'm familiar with a manual impact, I don't have one but I can get one. Mine's a Bosch 18v cordless impact wrench/driver. I'll see what syncing does :)
 
Also check cables to make sure you have them routed correctly and there should be a little play in cables to allow carb to rest on thumb screw stop(idle adjusting thumb screw).
 
if your idle is way up not sure you will get a correct sync job.

first off with the bike off when you twist the throttle open does it SNAP shut when you let go? if not its not closing all the way. check all cables are free, you can move them while the bike runs and see if that chg the idle at all and that would lead to a tight, kinked or pinched cable.

do you have a throttle lock cruise control, it could be binding up your throttle, take that off for now and check.

look at all 4 choke plungers, maybe one or two are stuck open and causing the issue, make sure all are closed.
 
It's possible to have a carb so far out that the sync screw bottoms out before it will come into adjustment. In that case one of the tabs can be bent to compensate....I don't remember which tab it is (probably the furthest away from the srew head) but it bends surprisingly easy, leading me to believe this is a factory engineered 'field fix.'

I discovered this on a bike that had been in a pretty violent crash and always figured the impact had somehow bent the sync bracketry, as it was running fine before the wreck.
 
yup danny those have to be clean and lubed(think i saw you do that a few times this one time at BRC lol) to operate nicely. the non snap shut will let you know something is binding and i mean SNAP shut, should hear it with authority.

think the adjustable brackets is for the manufacture discrepancies and ya field fixes. must have know the westerners would use a heavy hammer to fix things hahahah
 
The 2 upper cables are new, 2 lower cables I Was able to reuse as they didn't have any damage, I lubed all cables before installing them with 'Cable Life', and the throttle does snap back into place (with authority, lol)..... Now, during the accident, something - possibly the scoop impacted with one of my diaphram covers hard enough to puncture a hole in it, so it 'is' possible something is bent.... I have no cruise on my bike.

Danny, these 'tabs', can you explain which one's you are referring too?
 
he's talking about that the sync screws hit to adjust the butterflies on the carbs, if one or more are bent they can be holding the butterflies open a bit more on one then the others and cause the idle to do up. take a look down the carbs from the top and see if one is more open then the others, will have to pull the slides up to look at them. should get you close to a sync by visual aid then use carb tune for final adjustments.
 

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