to fast idle

Ceymore · Post by **Ceymore** » Wed Sep 05, 2012 6:38 pm

Hi all,
Greetings and salutations from a recent G80s owner (1952) purchased from a club member.
I have a slight problem with the idle on my fine machine in that it ticks over to fast,the idle screw is backed off from the slide and the slide is not sticking and it is shutting off all the way, if I adjust the mixture screw to slow it down then it runs eratic.
Any help muchly appreciated.

Cheers
Cliff

Rob Harknett · Post by **Rob Harknett** » Wed Sep 05, 2012 6:59 pm

You are new to the machine, perhaps the tick over is ok, if you want it to tick over and not spit spluttter stop. The club owner that sold it too you must had been satisfied. How have you got the manual advance retard lever set, have you tried to retard it a bit that will slow the tick over

iandusud · Post by **iandusud** » Wed Sep 05, 2012 7:09 pm

Make sure that there's some free play in the throttle cable. Assuming that there is it sounds to me like a worn throttle slide, possibly allied to a worn carb body as well, but often just replacing the slide will suffice.

Ian

1608 · Post by **1608** » Thu Sep 06, 2012 12:38 am

I know someone who recently had the same problem ( old triumph single) but the principle is the same. Having tried everything to do with carb and timing etc. to no avail, the problem was eventually found to be worn inlet valve guide.

Don Madden · Post by **Don Madden** » Thu Sep 06, 2012 6:32 pm

Or maybe just idling on side stand, which leans the bike enough to starve the jets. To get a slow tickover the mag must be well retarded & the carb carefully adjusted. Slightly rich idle adjustment gives more even tickover & easier starting. Cheers, Don.

Wumpletoad · Post by **Wumpletoad** » Mon Sep 17, 2012 9:59 pm

quote:
Or maybe just idling on side stand, which leans the bike enough to starve the jets. To get a slow tickover the mag must be well retarded & the carb carefully adjusted. Slightly rich idle adjustment gives more even tickover & easier starting. Cheers, Don.

Good advice.

Young people - well, people younger than me! - who have grown up with automatic ignition systems (and they have been around for a while now), seem to have problems understanding the workings of the lever. If the static timing set for full advance is correct, the engine will not idle smoothly without some spark retardation. That's how it should be - the lever's not just to stop you busting your ankle and its use is fundamental to riding an old bike.

And while I'm at it, be sure to have the magneto set to "slack wire advance". Over the years mags often have been replaced with ones from other bikes or the handlebar lever may have been swapped with one working in the opposite sense. Either way, the fully advanced setting determined by the pull of a flexible cable is not the best method of doing it.

Wumps.

zwarts · Post by **zwarts** » Tue Sep 18, 2012 10:12 am

Slack or tight wire advance - it makes no difference to the range of advance available. This is determined by the stop pin in the mag body and the the slot in the cam. Movement is positively stopped in both directions and does not rely on the range of cable movement available.
Bob.