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750F2 erratic tick over.

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royhall:
I think this may have been covered extensively as it appears to be a common problem.

Cant seem to get a good reliable tick over with these PD carbs. The bike runs superb, but as the engine warms properly the tick over gets faster. Also if I turn the throttle control hard backward, to tension the close cable, the tick over drops. I have checked the setup of the cables and there is plenty of slack on them and the return spring pushes the shaft hard back against the throttle stop.

The carbs have been completely apart and thoroughly cleaned etc. I have however just noticed that two of the felt washers on the spindle shaft are missing, would that cause a problem? Does anybody know where I can get a set of these felt washers. Cant find them anywhere and they don't even have a part number in my book.

On the idle screws, can I just verify I am correct. When the screw is turned out does the idle mixture get richer or leaner?

Will get to the bottom of this eventually, just need a bit of patience and effort, "O" and a load of help from you guys again.

Cheers all.

Lobo:
Hi Roy,

I had this felt washer prob when rebuilding my 400F carbs, and frankly was unsuccessful @ making new ones as per all the advice on the Internet.

In the end I bought a job lot of assorted vinyl grommet type washers, and bingo there was a size that fitted beautifully. Haven't looked back....

Book figure (F2) from my manual is the pilot screws @ 1.5 turns out.

I'm no F2 expert, but saw this on an F2 thread... I read it as screw gently home = lean.

"The pilot screws block the entire pilot circuit from delivering fuel.  If the acell pump is working and the throttle held open the engine will start and race, but dies at/near idle settings."

The below possibly of use, (type "Felt" into the search box of first link)

Good luck,
Simon

http://www.motorcyclecarbs.com/search.cfm

http://www.hondachopper.com/garage/carb_info/tuning101/carb_tips.html

martin_uk:
Did the carb clean include removing push fit pilot/idle jets?

royhall:
Cheers Martin. Yes it did, I cleaned everything manually including taking out all the pressed in stuff and running through with a guitar string, then they were ultrasonic cleaned, then I cleaned them again. Mystified about the way twisting the grip backwards to tension the return cable drops the tick over. Wondering if I put enough turns on the return spring when I built them up, but it is returning hard to the stop? Plus there's a few of the felt spindle seals missing so I think the carbs may be coming apart again? Sigh. I suspect I may still have air leaks at the intake rubbers. :( :(

martin_uk:
Did you get old O rings out of mixture screws orifice OK?

Spring on screw, then washer, then  O ring.


Have you double checked the fast idle part of choke linkage is clear when not full on and make sure linkage connected to cable  "toggles" ? (assume F2 has cable choke)

Sorry if Im covering points you have already checked.

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