Engine idling issues

[andrewsmith]

Afternoon

I've just got back in off the bike for the last time this year (am being a woman and not riding through the winter), and went to come back home and the bike refused to idle properly until it was at running temp, but was idling fine of the choke or throttle after few secs. Take it off and did it again.

It was behaving like wet plug syndrome, but it aint as its well coated in grease and acf50.

Weather aint that cold today neither.
Any guesses?

Thanks in advance
Andy

Gummy choke plungers? Had horrific idle and misfire problems last winter, cleaning up the plungers which were in a right state and not sliding properly helped (but I also fitted a fender extenda at the same time, so that may have helped also).

Changed the choke cable, plunger springs and o-rings and greased and cleaned it all up properly a couple of months back in anticiptation of this winter, and so far, despite weather being pretty cold and wet recently, no problems.

No doubt others will have further ideas, but may be worth a check over winter anyway. Good luck.

[andrewsmith]

i think its plungers as the clutch cable is more temprimental than a italian welder at friday lunchtime.

Probs swap it over the winter as i'm fiddling.
How hards a job is it?

Not a hard job, just a bit faffy.

Tank off or propped up (don't prop up a full tank - it will leak from the filler cap!)

Airbox off (one hose clamp and a couple small rubber tubes iirc)

Haynes says remove carbs. However, unless you are planning on changing throttle cables at same time, not strictly necessary. Just unclip from rubbers that feed into cylinders and displace a little. The screw on the front plunger plate is pretty much unreachable unless carbs are lifted a little, and if the screw is seized a bit, you will need to get the driver dead straight on it or risk a chewed up screw head.

Remove plungers, clean up the bores they sit in (tiny screw driver used VERY gently and a couple of cotton buds are useful), clean up plungers. If you are taking plungers off cable, make sure you keep a damn good hold on the spring, or risk searching for the bugger as it pings off 50 yards into neighbours garden.

Fit new (lubed) cable or lube old one and pack grease into splitter box. Reassemble.

Routing of cable is a little fiddly but not too tough, and removal of cable from bar end is not tough at all.

If, like me, you need several cuppas while spannering, probably an hour and a half, two hours. If you know what you are up to, probably a lot less.

If other cables are dodgy, probably a good time to change them too. Not done throttle myself, but changed clutch cable and its pretty straight forward.

Cheers, Jez

[fizzwheel]

Trouble with the plungers is that the screws that hold them in are made of cheese and corrode in place and they can be a right b*stard to get undo.

I had to remove my carbs to get enough pressure on the screws to get them undo and I also ended up cutting a big slot in the head of one of the screws and using dirty great big flat bladed screwdriver after I rounded the heads on them.

[andrewsmith]

Cheers Jez.

It'll be a couple cup o tea job. The tanks coming off anyways for a new air filter and clutch cable

[andrewsmith]

Originally Posted by fizzwheel

Trouble with the plungers is that the screws that hold them in are made of cheese and corrode in place and they can be a right b*stard to get undo.

I had to remove my carbs to get enough pressure on the screws to get them undo and I also ended up cutting a big slot in the head of one of the screws and using dirty great big flat bladed screwdriver after I rounded the heads on them.

Industrial levels of swearing is mandatory with my bike
I might order new ones as I'm expecting them to be siezed

I think I'll be looking at my choke plungers this weekend- something doesn't feel quite right with them...

I'm praying that the screws are in good nick! Will try and get some more GT85 down the cable too, as that has helped at the bar end.

[Vindaloo]

I'm thinking I may be doing just the same this weekend whilst it's in bits and if I can find the time.

Looking in the Haynes, they recommend putting together a bizarre contraption for oiling the cables. Has anyone had success with this? It looks to me like a rather convoluted way of making a complete mess and getting oil all over your bike ... which I'm perfectly capable of doing on my own in a number of other ways.

Adrian

If you have oil/lube in a bottle that squirts, and a steady hand, not entirely necessary to make blue tack funnels, bags or what ever it is that Haynes recommend. Hang cable on garden gate. Squirt some lube in top. Go and do something else for a couple of minutes, clean chain, pull weeds, whatever, then squirt again, repeat. After not much time (15 minutes at most )you will find oil dripping out the bottom end of the cable and job is done.