No choke, No problem?

[Jiu Jitsu Player]

Here's a pretty noob question but I was wondering- is it bad that I have never had to use the choke on my bike? Since its usually pretty warm here, I've never had any problems just starting it without the choke. I was just wondering whether I should just try using it once or twice for the hell of it or whether never using it would lead to some problems down the line. thanks.

[DmbShn41]

This is just puerly my experience:

I live in SW Ohio, and we have cold winters and hot summers. In the spring, such as now, I have to choke and warm up the bike in the mornings and later at night. In the summer, I normally let the bike warm up, with no choke, then ride.

If and when I use the choke, I really try not to ride with it, unless I absolutely have to. By the 2nd or 3rd stop light when the rpms climb at idle, I turn it off.

If you use every once in awhile just to check if its working, I don't think that would hurt anything. Use a little extra fuel I would guess, but just don't ride around with it.

[kkim]

so, when you start the bike w/ no choke, what rpm does it idle at initially?

[Jiu Jitsu Player]

1to 2 rpm then it creeps up to 2 to 3 after a while.
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[kkim]

lol... that's a bit low. You mean between 1000- 2000rpm?

what is it when you first start up the bike after it's been sitting all night? 1-2K is such a wide range... it shouldn't do that. Which is it, 1k or 2k?

your idle should be 1500rpm after fully warm.

[Jiu Jitsu Player]

After a cold start with no choke it idles @ around 1400 rpm. Once she's running and warm, idle is around 2400.

[kkim]

That's the "problem". Idle should be set to 1500 after the bike is completely warm (10-15minutes of riding) by adjusting the idle adjustment knob on the side of the bike. If you were to do that, you'll find you will need to use the choke at start up or the bike won't idle.

Your idle speed is set too high right now, you need to adjust it.

[Jiu Jitsu Player]

Where is this knob? Do you have any pics or a DIY link or something? Thanks

[kkim]

look in your owner's manual on setting the idle speed.

it's on the left hand side of the bike, right below the black side panel.

[Buffalony]

around 1350 rpm. I idle mine around 1450. Just preference.

Anyone else here have to adjust it often!
Maybe just depends on the weather for me!

[kkim]

I had to play with the idle a lot to get it to settle, but after a few times it got pretty stable. I do notice at work at 3500' level and a colder ambient temp, the bike is harder to start and to keep running from a cold start. Once lit, the choke can be used to regulate the idle speed.

[Buffalony]

Yeah I think it was when it started getting colder up here that I started to adjust more frequently. I remember using the choke the way you did . Isn't it bad to use the choke in this manner though? Just asking.

[kkim]

in what manner? that's what it's for... to keep the bike running till it warms up.

[Buffalony]

Originally Posted by kkim

in what manner? that's what it's for... to keep the bike running till it warms up.

As an alternate to adjusting the idle speed after the bike is warmed up.

[kkim]

Originally Posted by Buffalony

As an alternate to adjusting the idle speed after the bike is warmed up.

yes, I use the idle adjustment knob to set or reset the idle speed back to what I want depending on the conditions on a fully warmed engine. I use the choke to keep the bike revving during warmup above an rpm where the bike will stall due to it not being up to temp.

I would never use the choke as an aid to compensate the idle speed on a warm bike.

[Buffalony]

K. What does the idle actually control? The Butterfly? Would this over enrich the mix running like this? Your brain on tap.

[zeroth]

Maybe I'm not the one who should comment on this, but based on just looking at the idle adjust knob and what it does, it seems to adjust the minimum throttle open position. So yes the butterfly. I don't believe that would adjust the mixture, just the minimum amount of air+fuel that would enter the engine.

Does that sound right, Kelly?

[kkim]

yes, the idle adjust only moves how much the butterfly can close and in turn regulates the amount of air being allowed to mix with the idle circuit gas. Other than idling at 2500 rpm, I don't think you can damage it, but it's not good to be idling at 2500 when hot. That's why they designed the choke.

On the other hand, to tell you the truth, I have no idea exactly how the choke circuit works on these bikes. I've never looked that up in the service manual.

[Buffalony]

Yeah I deff. would not idle that high. Thanks for the replys.

[g21-30]

Originally Posted by kkim

On the other hand, to tell you the truth, I have no idea exactly how the choke circuit works on these bikes. I've never looked that up in the service manual.

The choke circuit is NOT a plate like in automobile history, instead it is just another needle like circuit, referred to as an enrichener (see pic)

When you set the choke lever on the handlebar, you're just withdrawing the needle from the jet.

[Buffalony]

So if you open the choke some, and your withdrawing the needles. Then wouldnt that have an effect on mid-range. Or is it only affecting the idle circuit?

NM. I gotta get in there myself to see whats going on.

[Jiu Jitsu Player]

Found the knob and adjusted my idle range to 1400. I haven't cold started the bike with the idle set at that rpm yet so I'll have to see if I need the choke or not.

[g21-30]

Originally Posted by Buffalony

So if you open the choke some, and your withdrawing the needles.

I used the term needle loosely. The choke operates another needle in each carb. Not the needle that you shim with washers. Don't confuse yourself. There are links under the DIY section (where I found the above picture), which explain the internal operations of the Keihin carbs on our bikes.

[Buffalony]

k. I'll be in there soon. thanks