idle issue

[Tomchri]

I look at my exhaust valve going down and up and intake going down and up. Piston TDC, thats it. But again as Pete said, better to be safe. Good luck.

Cheers Tom.

[pete roper]

This is a simple and easy explanation of how a four stroke engine works. I suggest you leave sound off so you don't have to listen to the irritating music!

 

https://youtu.be/TEIhXNwfkL8

[audiomick]

Yes, watch the valves as you turn the motor. In combination with the "drinking straw", this will lead you to the "correct TDC".

When you think you are there, if you can't move the rockers a little bit by hand (so that they click just a bit), either you are not there or the valve clearance is way too tight. More so than is reasonably likely.

 

You are right, setting the valve clearance is more or less the same procedure on any 4 stroke petrol engine.

 

If you are not that sure about how they work, look here:

https://en.wikipedia.org/wiki/Four-stroke_engine

There is an animated picture right at the top that shows how the valves are both open at the one TDC, and both closed at the other TDC where the engine fires (which is where you want to set the clearances).

[docc]

29 minutes ago, pete roper said:

This is a simple and easy explanation of how a four stroke engine works. I suggest you leave sound off so you don't have to listen to the irritating music!

 

https://youtu.be/TEIhXNwfkL8

And, here, I have been anticipating the colorized P.Roper tutorial of:

                                 "Suck-Squeeze-Bang-Blow" . . .

 

[audiomick]

24 minutes ago, docc said:

                                 "Suck-Squeeze-Bang-Blow" . . .

Ummm, no, I won't go there....

[LowRyter]

7 hours ago, mikev said:

found this thread while researching this more.  we were getting closer than I thought to TDC last night using a modified "straw" method.

 

mark your alternator fin once you got it!

[pete roper]

Remember the crank rotates clockwise when viewed from the front.

[audiomick]

2 hours ago, pete roper said:

...the crank rotates clockwise when viewed from the front.

which reminds me, I've had the recommendation many times to always rotate the motor "forwards" in to the position at which you are going to check your adjustments. This makes sure that the play in the cam chain etc. is all taken up properly the way it is when the motor is running.

Turning the motor backwards could theoretically "move the play around" or at least have things at the "wrong" side of the lash movement.

Turning the motor backwards whilst doing your adjustments wont break anything, but if you have need to turn it backwards for any reason, go forwards to where you want to get to as the last movement before checking adjustments.

[docc]

On 7/23/2023 at 3:17 PM, mikev said:

I went for a ride today, perfect weather.  Made a couple stops, bike was running fine for about 100 miles.  Stopped at an intersection to have a quick word on the route.  No issues idling.

Drove up the road a ways didn't notice anything on the way but at the next stop light my V11 stalled when I idled.  Started right up fine, but from then on the idle is weak and it wants to stall.  Was able to ride it 20 miles back home.  Gave it a bit of an Italian tune up once or twice on the way but the problem persists.  Choke seems to help a little but maybe not as much as before on a cold start.  Changed the first 3 relays to be safe, no change.  Neutral light no longer seems to light up, not sure when in this sequence of events that might have started.  Pulled the plugs and they seem fine, just changed them last Fall.  Looked damp and smelled a bit like gas. 

Any ideas on what to check next?

 

Thinking more about a hot engine restart, especially in high ambient temperatures, I am reminded of the fact that the fuel/ignition mapping runs a rich condition for >4000 revolutions (it is an exact number that @Lucky Phil shared with us) on EVERY start-up regardless of actual engine/ambient temperatures.

Under certain conditions (hot motor + hot air) this could contribute to very poor running, especially at idle, during that enrichening period.

[LowRyter]

On hot restart, make sure the fuel pump is primed and tank is vented.  If it doesn't start due to that, open the gas cap and add fuel as necessary.  Don't ask how I know this.

 

Public service notice

[mikev]

I did the valves last weekend as recommended, home renovation project delayed my bike project.

Idle is better but still not great.  

[docc]

30 minutes ago, mikev said:

I did the valves last weekend as recommended, home renovation project delayed my bike project.

Idle is better but still not great.  

What did you choose for cold valve lash settings?

[mikev]

.006 intake and .008 exhaust

[docc]

3 hours ago, mikev said:

.006 intake and .008 exhaust

On to the other parameters that affect idle, then.

TPS, of course, and throttle body synch.  Even some seemingly minor tweaking of these critical settings can make for profound outcomes . .  .

[mikev]

Went over to the bike to see if i could locate the right side idle set screw and noticed this.  seems like the left side is not firmly connected to the engine and air is getting sucking in through there.  like it got pushed back or something.