High Idle

[luckyd20]

Can i get assistance on where should my idle be at when idling after a full warm up. As of right now, it'll idle around 2100 I think it's suppose to be around 1750 if I'm not mistaken. I do feel that I need to sync my carbs but what can I do to help bring down my idle?

[bruce_launceston]

Idle should be about 1100 rpm, I run mine at closer to 900rpm without it stalling.

If the carbs have been balanced with the engine at full operating temperature you should be able to get the idle much lower that you have.

If the carbs have been disassembled for new 'o' rings etc you may need to check that the butterflies are seating correctly. They should close almost light proof. If you pull the carbs off so that you can look through the throat, hold them up to a light and check the seating.

If they are not seated correctly it will be impossible to get the idle right down to where it should be.

If the carbs haven't been apart you need to rebalance them making sure that the engine has been warmed fully before you start.

There are good instructions on the net, but sometimes they don't cover adjusting the air screws.

[Mike V]

Lucky,

That's quite high in my opinion.  I set my idle with a fully warmed-up engine at about 950rpm, ±100rpm.  Start by turning your idle speed adjusting screws counterclockwise equal amounts at each carburetor in about 1/16th turn increments until you reach that value.  Go ride the bike, make adjustments (in either direction) as necessary. That's the short answer, let's start there then discuss carb synch and cable adjustments if needed.  Don't allow the bike to idle for extended time periods during the adjustment process.

If you're not sure about the procedure review your owners manual for direction or let us know and we can offer advice.  

-Mike V.

[Barry]

79 models will idle at a lower speed than the later bikes because of the heavier flywheel.  900 - 1000 rpm is plenty fast enough. My 79 will idle reliably right down to 600 or 700 rpm which is impressive but not advisable from a low oil pressure point of view.

[steve hawkins]

My 1979 R65 has a 'lightened' heavy flywheel, and will idle below 1000rpm, as Barry says above.

However I tend to set my idle a little higher (1200-1400), especiallygoing to work during winter months when I am trickling slowly through traffic in the dark, as I want to reduce the drain on my battery over the week.  

When the alternator light comes on your battery is not being charged.  
It needs more that 1000rpm to get the alternator light to go out.

Otherwise by the end of the week I wont be able to start the bike!

Cheers

Rev. Light

[Bob_Roller]

Before you attempt a carb synch, check the valve clearance on a 'cold' engine, too tight of a clearance will cause idle issues .

Check your cables for a bit of slack/freeplay in them .