dead spot in throttle

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el rojo
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dead spot in throttle

#1

Post by el rojo »

I finally was able to road test the bike after tweaking the air/fuel screw so that she didn't cough. I am about 95% there. Running threw 1st and second no problem but when I hit third and am slightly below my power band and at about 20% throttle, she will cough a little and I feel a little lagging in power kinda like running at that speed with the spark retarded I guess.
When I go above the 20% throttle on up threw the power band, she runs great, no lagging, no coughing but the same thing happens when I hit fourth gear. I really feel that this is a carb issue but not sure. I am wondering if it has something to do with the mid range jet size being wrong? I also noticed that when I got back, I noticed that there was a lot of oil on the right side of the case and it looked like the push rod tube O rings weren't sealing properly at the heads. The old ones were cork and the new set I bought are rubber.
Rojo
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Re: dead spot in throttle

#2

Post by 59Panman »

Try to open the low speed screw a turn at a time. You may still have it too lean.
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Re: dead spot in throttle

#3

Post by Tattoo »

Are you sure your timing is right?
58flh
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Re: dead spot in throttle

#4

Post by 58flh »

Check the color of your plugs.--It does sound as it may be lean as said.---Respectfully---Richie
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Re: dead spot in throttle

#5

Post by el rojo »

ozwick86 wrote:Try to open the low speed screw a turn at a time. You may still have it too lean.
Thanks Mark,
which way should I turn the screw to go richer?
Rojo
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Re: dead spot in throttle

#6

Post by el rojo »

58flh wrote:Check the color of your plugs.--It does sound as it may be lean as said.---Respectfully---Richie
Richie,
Both plugs are dry and white.
Rojo
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Re: dead spot in throttle

#7

Post by 49bones »

el rojo wrote:
ozwick86 wrote:Try to open the low speed screw a turn at a time. You may still have it too lean.
Thanks Mark,
which way should I turn the screw to go richer?
Rojo

If its a Linkert clockwise is to lean and anticlockwise to richen, both low and high are the same although the setting for them are very different. You should be able to find a base setting for any carb and work from there, but take a note of where it is now so you can always go back to this point.

I must say I'm in th process of setting up a carb at the min, takes time but feels good when you get it right.
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Re: dead spot in throttle

#8

Post by 58flh »

ELROHO---You said both are white!--That is LEAN!/& not good---As was said Clockwise for lean & Counter clockwise for richer mixture.-----Try to shoot for a dark tan or COCO-Brown color!-This is considered Ideal burn.----Richie
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Re: dead spot in throttle

#9

Post by 58flh »

ELROHO----There could be another possibility!--Where I live on the East coast SHELL is selling fuel that has somekind of corrosive additive they call -(INVIGORATE)-Thats how there advertising it & they say----Cleans Combustion chamber Valves & pretty much anything that gas is going to go thru!.Im not-sure about the others But all fuel is crap today where I live.I use MMO faithfully since POP got me my first basket-case at 16.I can say from yrs. of Top-end jobs that Some of the guys I ride with didnt use MMO.When it was time for top-end work ,I could take a rag spray a little carb. cleaner on it & without any hard pushing work--Im down to my cast pistons & can read the .040 bore numbers!--Also the carbon ridge at the top WIPES AWAY!---Now the other guys / a few pans Flatheads/slab/shovels--That didnt use it --You would have to use a RIDGE-REAMER to get that carbon off!/& Pistons were Were wheeled to clean/(yes with soft brass wire wheels).Now Of course none of us would use a automotive Ridge-Reamer to remove carbon on the barrels/ It was just that BURNT on there!--After comparing & the boyz seeing it first hand over a span of a few yrs.-(STUBBORN)-you know what I mean :lol: /Were all using MMO on every fill-up.I have 5-gallon tanks/ cause I like the x-tra fuel/I add 4-ozs.-to 5 gallons.I find that its a perfect mix for that amount.-We all have different tanks so they played with it & found the happy amount.I am in no-way saying go & buy this you need it!--I am just reflecting on my findings & sharing it with you.I hear in some places you can still get LEADED GAS!.Where I live its all crap & its getting worse all the time I think.Just something to think about.Maybe if you have found yourself Richening-up To get your normal burn & Your not leaking air into the system Maybe its the shit that there putting in our fuel????-I dont know but it makes you wonder.-----Respectfully----Richie
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Re: dead spot in throttle

#10

Post by neilw »

I'd do a compression test , sounds like a burnt valve to me.
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Re: dead spot in throttle

#11

Post by RUBONE »

neilw wrote: Mon Aug 10, 2020 1:50 am I'd do a compression test , sounds like a burnt valve to me.
Not sure if you noticed or not...this thread is five years old. :D
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