carb long brass screw

[Macrofeet]

i read someware, someone was having powerloss when pulling away, and their carb seemed to be leaking a tiny amount of petrol,

i had the same problems start last night and was loosing power, as i had only just done the carb deristriction i assumed it would be to do with this and i was right

messed around with it for many hours today and got to wondering how would moving the washer a tiny amount make any diffrence removing the the screw will clearly let the needle raise much more

so this got me thinking that maybe the screw should not be taken out

put the screw back in and now there is no more leaking and better power

after this i messed with the fuel mixture screw and it had much more effect "set to 2 turns"

removing the screw made the engine flood when i pulled off

[chcknugget]

I hope you removed the screw under the black cap on top of the carb. Removing the brass screw on the side of the carb will definitely cause leakage and running issues!

The higher the screw rides, the more fuel is let through. Removing the brass screw will let the pin ride higher and let more gas in. Lowering the washer on the pin makes the pin ride higher, letting more gas into the engine again. Basically, the pin is plugging the jet hole for less time as it moves up and down.

I hope this helps.

[Macrofeet]

"Removing the brass screw on the side of the carb will definitely cause leakage and running issues!"

;D yeah so does leaving the disk lock on well running issues anyway

after the screw is taken out the engine seems to flood i think this might be to do with the white plastic thang floating to high i know someone else on this forum had what sounded like the exsact same problem with the fuel leak and power loss

[baotian]

WOW i would never of thoght that as i am the 1 having the problems, i will place the brass screw tonight!

hopefully it should sort it all out without loosing the power.
Thanks alot macrofeet.
i will let u know how i get on

[Macrofeet]

okay kewl i hope it fixes your problems m8

[Macrofeet]

Nicked of preloved forum, i think some one from this forum posted

"I had the same problem, I am sure the problem is caused by fuel starvation after de-restriction, it seems to be very common, try this it worked a treat for me:-

Remove the seat and surrounding cowl, (4No 12mm nuts) remove the existing in line fuel filter situated behind the carb and replace it with a larger one (£1:50 from Halfords) site it as low as you can level with the carb, if you are able to shorten the fuel line a little then all to the good.
Now take the vacuam pipe off where it joins the air system and shorten it as short as possible without straining it."

i think this will probably help when i took the brass screw out i had to massivly open up the mixture screw to make the fuel richer(2 rich) for the bike to work anyware near normal

[Macrofeet]

Replaced fuel filter today with slightly larger one(2.99 moter world) also made fuel pipes smaller have no tested properly yet seemed better on short run no power loss,

Oil leaked out of oil cap prob made oil pressure higher tighted cap seems okay now

[baotian]

ok sorry for the late reply but just come back from holiday,
i tryed replaceing the brass screw, and yes it did stop the flooding when i pull away, but it killed my acleleration, so i put it back on.

also is it normal thats when you take the black plastic cap of the top of yor carb where you can see the black rubber seal, is it normal for the seal to be crinkled and wet.

but it is still sealed shut

thanks

[Macrofeet]

I think finally got my bike to work the way it should but i still need to tighten valves a lil and test more

here is what i did

• loosend back brack off a little was set to tight
  
• Replaced fuel filter with moter world filter 2.99
  
• Made fuel line shorter both sides of filter
  
• Made air line shorter
  
• Cut screw in 1/2 and screwed into carb cap about 50% shorter then brass screw engine seemed to over heat otherwise after about a mile and i found fuel in the airbox
  
• Set mixture screw to 1 3/4 turns
  
• Cleaned spark plug with fine sand paper and rag
  
• set spark plug gap to 0.65
  
• Set valves one was slightly tight to 0.05
  
• Cleaned engine by trickling water in carb(water turns to steam when the pertrol is burnt off the hot steam cleans the engine (putting to much water in would kill your bike off)
  
  The last thing i did was trim the air line and loosen the carb screw a little
  

So far 30 - 33 mph better accelaration with what seems like no flooding no over heating

[baotian]

so is your ped not deristricted ? becasue mine easerly doese 38-40 on a flat.

i tryed replaceing the brass screw, and yes it did stop the flooding when i pull away, but it killed my acleleration, so i put it back on.

also is it normal thats when you take the black plastic cap of the top of yor carb where you can see the black rubber seal, is it normal for the seal to be crinkled and wet.

but it is still sealed shut

thanks

[Macrofeet]

Everything but the slip ring

My carb is the same but to start with it was tight i dont think it matters as long as its sealed

here is somthing to try that wont cause you 2 much hassle

Pull the air pipe up and round a lil bit if you notice improvment take the pipe off and cut it shorter so it dont sag