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New A/F screws seem aweful tight.

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Jims05vmax

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Hello, last year I Bought a 05 that had stage 7 installed. It had a crap idle off choke from sitting for a year so attempted shotgun clean. Cleaning went OK till I got to right rear carb and found the A/F screw missing. I Ordered a replacement and bike idled better so I rode it and was too loud for my liking so over the winter I put the stock exhaust back on. I have not changed the jets/springs/needles yet. Having all the OEM parts and a dynojet kit plastic box with everything in it but have to figure what exactly was changed and what was not before swaping parts. This spring went to start and the idle was bad again. Decided to change out the rest of the A/F screws since 4 were purchased. I remember having to work the 1 new screw with some oil in and out several times before I could tell it was seated but these are so tight I can not tell when I am lightly seated. Out of the folks here that installed new screws did you find them to be really tight and if so how did you get the screws to seat lightly being tight? Pretty sure I don't want to try chasing threads with a tap. This bike was a tuned and tested UFO bike till the last owned stopped riding it due to medical reasons.

Thanks. Jim
 

dannymax

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New mixture screws tend to be a slightly larger diameter because they haven't been 'worn in' yet....also the female threads probly have a little bit of crud in the valleys.

Unfortunately chasing the threads is the best way to loosen them up....but without the carbs torn down it's difficult to keep filings and other fine material from getting in the carb passages.
 

Donny Daughtry

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Hello, last year I Bought a 05 that had stage 7 installed. It had a crap idle off choke from sitting for a year so attempted shotgun clean. Cleaning went OK till I got to right rear carb and found the A/F screw missing. I Ordered a replacement and bike idled better so I rode it and was too loud for my liking so over the winter I put the stock exhaust back on. I have not changed the jets/springs/needles yet. Having all the OEM parts and a dynojet kit plastic box with everything in it but have to figure what exactly was changed and what was not before swaping parts. This spring went to start and the idle was bad again. Decided to change out the rest of the A/F screws since 4 were purchased. I remember having to work the 1 new screw with some oil in and out several times before I could tell it was seated but these are so tight I can not tell when I am lightly seated. Out of the folks here that installed new screws did you find them to be really tight and if so how did you get the screws to seat lightly being tight? Pretty sure I don't want to try chasing threads with a tap. This bike was a tuned and tested UFO bike till the last owned stopped riding it due to medical reasons.

Thanks. Jim
You can take the cap off of the carb and spray into the air jet with the a/f mixture screw out--your choice of spray-pb blaster, wd-40 or carb cleaner to try to clean out the threads. I use a q-tip sprayed with wd-40 and roll it in the inner threads. If they installed a stage 7 here is what should be in it-----

http://www.dynojet.com/pdf/4716.pdf

You should be able to look at the contents of the kit and probably determine what has been installed in yours.
You are not going to run well at all with a stage 7 kit and and a stock exhaust.
You would be better off going back to the stock settings in the carbs using the stock exhaust-(needles,jets,springs)-Check to see if the slides have been drilled and the carbs have been plugged ie the Stage 7 kit.
 

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