High Idle - Throttle Stop Screw
#1
High Idle - Throttle Stop Screw
Greetings!
Have recently acquired a '95 CBR F3, and am itching to ride (it replaces my '84 Interceptor 500). I have one problem... it Idles at around 4k. I've tried twisting the Throttle Stop Screw to adjust the idle, but it doesn't seem to want to move. Is this supposed to freely twist left/right with ease, as in full rotations?. Is the entire cable supposed to twist, or just the metal core encased in plastic? Either way, neither twist, or so it seems - well, the cable twists, but "springs back" would perhaps be a more accurate description - with no significant effect on the idle speed.
Presumably, one lets the bike run for a few minutes to "warm up" and then one simply dismounts the bike and twists this thing-a-ma-bob clockwise to increase, and counter-clockwise to decrease, or so the theory goes? Either way, it doesn't seem to do anything, and I certainly can't roll around town @ 4000RPM idle speed. Any suggestions? )
This is like getting a new toy at Christmas without the batteries, only worse, cause I bought it. FYI, it seemed to idle fine a few days ago when I test drove it. The seller states all he's done since then was replace the plugs. )
Any and all help/speculation would be greatly appreciated. I'll wait to see what you folks have to say before I start tearing it apart <Sigh>.
As an aside, does anyone have any "real world" pictures showing how the Throttle Stop Screw cable actually attaches to the Carb?
Have recently acquired a '95 CBR F3, and am itching to ride (it replaces my '84 Interceptor 500). I have one problem... it Idles at around 4k. I've tried twisting the Throttle Stop Screw to adjust the idle, but it doesn't seem to want to move. Is this supposed to freely twist left/right with ease, as in full rotations?. Is the entire cable supposed to twist, or just the metal core encased in plastic? Either way, neither twist, or so it seems - well, the cable twists, but "springs back" would perhaps be a more accurate description - with no significant effect on the idle speed.
Presumably, one lets the bike run for a few minutes to "warm up" and then one simply dismounts the bike and twists this thing-a-ma-bob clockwise to increase, and counter-clockwise to decrease, or so the theory goes? Either way, it doesn't seem to do anything, and I certainly can't roll around town @ 4000RPM idle speed. Any suggestions? )
This is like getting a new toy at Christmas without the batteries, only worse, cause I bought it. FYI, it seemed to idle fine a few days ago when I test drove it. The seller states all he's done since then was replace the plugs. )
Any and all help/speculation would be greatly appreciated. I'll wait to see what you folks have to say before I start tearing it apart <Sigh>.
As an aside, does anyone have any "real world" pictures showing how the Throttle Stop Screw cable actually attaches to the Carb?
#2
Hey welcome to the forum! If i remember correctly, the whole cord moves (black plastic with metal wire inside). You might try checking if it is bent around something weird that would not allow it to turn. Also, make sure it is actually connected at the other end. Not trying to make you seem stupid or anything..just best to start basic If no one has posted a pic by tomorrow, i'll get you one. But i believe the idle adjust cable runs up between the 2 sets. Like 2 carbs on left & 2 on right. Just between them.. Good luck!
#3
#7
i agree the cable may be broken inside the sleeve, as well as the choke issue, i had one expirience where my friend was ridin along and adjusted the idle screw and when i took the choke off it was idling at 4000 rpm's. be sure u check the basics out first before diving into the hard stuff
#8
Solved... err... kinda... maybe... perhaps...
Thanks for the advice folks, and big kudos for the picture. Turns out the little flat piston-like device at the end of the Stop cable was "stuck." By cranking the throttle, it allowed me to iplace press on the device with a screw driver, while simultaneously turning the Stop screw counter-clockwise. I can now adjust it up and down. Yay! My excitement, however, was short lived...
The frak'n thing won't start now... so I am unable to test for success. I get a "bang" and a shot of flame out the rear end if I hold the starter for 5 or so seconds. Totally uncool, and quite alarming at 4AM )
I started to check for fuel flow, but the fuel pump didn't seem to work (normally on my Interceptor, I can can hear the pump engage when I turn on the ignition). I suspected the battery may have been run down and/or is toast/not delivering enough power to fire up all four plugs and fuel pump because I checked the voltage (black/white wire) going into the Fuel shutoff relay and I get .72 volts with the ignition turned on (engine off). I tried shorting the (Fuel Shut off relay connector) Blue/Black to Black/White (center pin) to by-pass the relay, and the fuel pump still wouldn't work. Tossed the battery on a charger for 5 minutes and there's life in the fuel pump. Tried to crank the engine, I got one "gigga" from it, then dead. Disco'd battery, replaced and am currently charging a new one. Fingers and toes crossed... Will post results after charge.
Again, thanks so much for your rapid feedback. You folks are awesome!
I do have one other question, though. My steering lock doesn't work. I figured it might be because the sterring column may not have been turned all the way to the left, so I slacked the left handle bar adjuster off to allow the steering column to turn all the way to the left (without the handle striking the tank) and it still will not lock (can't turn it to the lock position in the ignition). Any thoughts/suggestions as to cause or fix?
As always, thanks in advance!
Thomas
The frak'n thing won't start now... so I am unable to test for success. I get a "bang" and a shot of flame out the rear end if I hold the starter for 5 or so seconds. Totally uncool, and quite alarming at 4AM )
I started to check for fuel flow, but the fuel pump didn't seem to work (normally on my Interceptor, I can can hear the pump engage when I turn on the ignition). I suspected the battery may have been run down and/or is toast/not delivering enough power to fire up all four plugs and fuel pump because I checked the voltage (black/white wire) going into the Fuel shutoff relay and I get .72 volts with the ignition turned on (engine off). I tried shorting the (Fuel Shut off relay connector) Blue/Black to Black/White (center pin) to by-pass the relay, and the fuel pump still wouldn't work. Tossed the battery on a charger for 5 minutes and there's life in the fuel pump. Tried to crank the engine, I got one "gigga" from it, then dead. Disco'd battery, replaced and am currently charging a new one. Fingers and toes crossed... Will post results after charge.
Again, thanks so much for your rapid feedback. You folks are awesome!
I do have one other question, though. My steering lock doesn't work. I figured it might be because the sterring column may not have been turned all the way to the left, so I slacked the left handle bar adjuster off to allow the steering column to turn all the way to the left (without the handle striking the tank) and it still will not lock (can't turn it to the lock position in the ignition). Any thoughts/suggestions as to cause or fix?
As always, thanks in advance!
Thomas
#9
Oh, and for the record, I removed the air filter and checked the choke. It seems to be able to fully deflect from right to left (as it enters the Carb area), and the throttle cables are also not sticking. I'm hoping it was the stuck Throttle stop screw, however, won't be able to confirm unless I manage to get the beast going. As an aside, what kind of monkey arms and special gadgets are required to change the plugs? Talk about no room, geez!
My apologies for the uber-newb questions. I'll just go back to playing with my toys
My apologies for the uber-newb questions. I'll just go back to playing with my toys
#10