Z1OwnersClub GB

Hi all, I've had my carbs off that many times i think i can do it with eyes shut, almost.
Seems the bike is running ok ish, ticks over nicely, best since i got it. Goes like stink when opened up, quite a suprise really, I had a 1200 bandit before the Z, so i was well made up. Enough, i degress. So at speed she seems to run well.
Starting is one area of concern, fires up easy enough but it is misfiring, choke on briefly. Misfire is gone when revved a bit, wont idle on choke but soons settles when warm.
Also, after she is warmed and run a few miles, tickover is fine but opening the throttle slightly/slowly results in roughness, a harder throtlle blip goes through with little/no roughness?

Checking the plugs after a good run shows no1 plug to be very clean, possibly weak, the other 3 show sootyness.
Carbs have all new jets, needle and gaskets. Full kit.

Also yesterday, towards the end of quite a hard run, probably 80ish for about 30mils(A50 from Derby to Stoke). Engine cut out at about 70 for 3seconds and then ran again! I did not catch the cut off switch.

Any thoughts/advice would be good.

Colm

In addition to replacing the carb jets etc i also checked valve clearances. Some needed adjusting. I was a bit worried about chacking adjusting the valves as i had never tocuhed shims before. Easy.

Hi Colm,
My A4 won't Idle 'till it's warm. I had problems similar to you, turned out just to be a dodgy plug. I also changed the wiring to give more voltage at the coils. Chrisu gave me this link and it worked a treat.
http://www.wgcarbs.com/index.php?option ... &Itemid=26

Plus I think you should sort out the valves first and start a process of elimination.

B

Hi, valve clearances are now all good and still same issue. Also changed plugs to Denso. Will check the link, Thanks.
Colm

Engine cut out at about 70 for 3seconds and then ran again!
Check for loose connections, springs in the kill switch, ignition switch broken wires - 80 ish for thirty miles is normal use.

Checking the plugs after a good run shows no1 plug to be very clean, possibly weak, the other 3 show sootyness.
Carbs have all new jets, needle and gaskets. Full kit.
Check and adjust the fuel heights then synchronise.

Rich wrote: Engine cut out at about 70 for 3seconds and then ran again!
Check for loose connections, springs in the kill switch, ignition switch broken wires - 80 ish for thirty miles is normal use.

Checking the plugs after a good run shows no1 plug to be very clean, possibly weak, the other 3 show sootyness.
Carbs have all new jets, needle and gaskets. Full kit.
Check and adjust the fuel heights then synchronise.

Cheers Rich, new switches fitted a little while back. So off with the carbs again. Smashin, though it is easy.

Did you change the needle jets along with the needles? These need to be a matched pair! Occassionally you'll get away with replacing just the needle but often you'll have mixture problems i.e. can't dial the mixture in with the airscrew.

My 2cents.

carbs balanced ??? - mine were WAY out after fitting new carb kits !

Crap in the fuel filter - you do have one don't you ......... ????

New needles fitted with needle jets. Not sure how to 'dial the mixture in' with the airscrew.

Will be checking carb balance again this weekend.

thanks

This may help.........Turn in the air screw of each carb fully but not tightly and then back it out 1 1/4 turns,start engine and warm up, adjust idle to about 800-1000 rpm.
Adjust each air screw 1 at a time,first turning in one direction and then the other until the highest idle is determined,if the idle rises too much adjust accordinly using the main idle adjusting screw.Note: if any any carb air screw can be turned in to less than 1/2 turn from full in,without idle change there is probably trouble with that carb(ie pilot jet/blockage etc).
Once highest idle is set turn all air screws in equally a small amount,readjust idle and check with vacuum gauges if needed.
Hope this helps good luck.

Steve S wrote:This may help.........Turn in the air screw of each carb fully but not tightly and then back it out 1 1/4 turns,start engine and warm up, adjust idle to about 800-1000 rpm.
Adjust each air screw 1 at a time,first turning in one direction and then the other until the highest idle is determined,if the idle rises too much adjust accordinly using the main idle adjusting screw.Note: if any any carb air screw can be turned in to less than 1/2 turn from full in,without idle change there is probably trouble with that carb(ie pilot jet/blockage etc).
Once highest idle is set turn all air screws in equally a small amount,readjust idle and check with vacuum gauges if needed.
Hope this helps good luck.

Cheers, will give it a go, love messing.

bollypne wrote:
Also yesterday, towards the end of quite a hard run, probably 80ish for about 30mils(A50 from Derby to Stoke). Engine cut out at about 70 for 3seconds and then ran again! I did not catch the cut off switch.

Any thoughts/advice would be good.

Colm

three seconds is a long time I would go with Rich cut out swith has bounced

KeithZ1R wrote:

bollypne wrote:
Also yesterday, towards the end of quite a hard run, probably 80ish for about 30mils(A50 from Derby to Stoke). Engine cut out at about 70 for 3seconds and then ran again! I did not catch the cut off switch.

Any thoughts/advice would be good.

Colm

three seconds is a long time I would go with Rich cut out swith has bounced

cheers Keith, new switches fitted recently. Will be checking all connections over the weekend.