If a coil is playing up it could turn the plugs sooty,
Are the down pipes all warming up the same when you start it cold?
Cylinders 1 & 4 are on one coil 2 & 3 on the other.
If it's running rich suddenly it might be the fuel cut off valves in the carbs are leaking due to dirt in them.

dobbslc wrote:If a coil is playing up it could turn the plugs sooty,
Are the down pipes all warming up the same when you start it cold?
Cylinders 1 & 4 are on one coil 2 & 3 on the other.
If it's running rich suddenly it might be the fuel cut off valves in the carbs are leaking due to dirt in them.

yup, i checked the coils out when i changed plugs earlier. its 1&4, 2&3. i cant figure out whether they are warming up @ the same time but as i sprayed wd40 on them 1 by 1, smoke can be seen. whats a fuel cut valve? overflow? i ever encountered dirt in carbs, overflow whenever engine starts. i hope its the o-rings leaking cos i'm changing them this week, hope end of problem.
i've got to ask, is the 3 screws for sync carbs easily spotted from top? cos till now i'm still not sure where's the screws for tuning but i'm going to strip it!!

VVS!! which are the 3 screws for tuning? possible to name the number in the carb part list?

http://www.400greybike.com/files/Parts_ ... ion1-3.pdf

Page 21 it's screw number 48. The screw should have a small spring and o-ring around the end of the taper,

Balance screws are screw no. 82, only one is shown but there are three.
Balance screws are on the outside of the carbs between each carb and have springs to tension them.
You adjust in pairs, first 1 and 2, then 3 and 4 and finally adjust the middle screw to bring the two pairs in sync.
Makesure every thing is correct first as they should not be synced if your floats and pilots screws are not all the same.

really thanks alot! i'm hoping to get it done in 1/2 day. basically, i'm just changing the o-rings as its not dirty, serviced 2 month ago but never changed o-rings. yup, i'll be very careful, slow & steady...

Variablevalves suck wrote:Balance screws are screw no. 82, only one is shown but there are three.
Balance screws are on the outside of the carbs between each carb and have springs to tension them.
You adjust in pairs, first 1 and 2, then 3 and 4 and finally adjust the middle screw to bring the two pairs in sync.
Makesure every thing is correct first as they should not be synced if your floats and pilots screws are not all the same.

VVS, base on the list, pg12/89, no.82 is a nipple. pg14/89, is a seal.. my guess is, is it no.79(screw), on top of no.80(spring) in the main digram page?

Ah, good catch VV. I thought he was talking about the mixture screws, guess I needed more sleep

Jaicen wrote:Ah, good catch VV. I thought he was talking about the mixture screws, guess I needed more sleep

there's only a few certain parts i'm still unsure of. slowly catching...