Topic: Spark plug color?

[DaveBarbier]

I'm sure people get confused. But think of the word "choke". It's a restriction. Choke on=more restriction so it's a richer mixture. When a bike is cold you put the choke on, as it warms up, you lessen the choke until it's completely off. All motors need a richer mixture when cold.


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1978 Honda CB550K

[grcamna2]

I'm sure people get confused. But think of the word "choke". It's a restriction. Choke on=more restriction so it's a richer mixture. When a bike is cold you put the choke on, as it warms up, you lessen the choke until it's completely off. All motors need a richer mixture when cold.


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1978 Honda CB550K

The more Choke you use it causes the butterfly in the back of the carb. throat to close & restricts the air inlet side of the carb. throat which gives you more fuel from vacuum pulling harder on the bowl jets and Not from the air inlet on our older style CB sohc4's stock carbs. There are other style carbs. on other makes and models(Honda included) which use an enrichener jet rather than a butterfly to restrict.

[DaveBarbier]

I'm sure people get confused. But think of the word "choke". It's a restriction. Choke on=more restriction so it's a richer mixture. When a bike is cold you put the choke on, as it warms up, you lessen the choke until it's completely off. All motors need a richer mixture when cold.


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1978 Honda CB550K

The more Choke you use it causes the butterfly in the back of the carb. throat to close & restricts the air inlet side of the carb. throat which gives you more fuel from vacuum pulling harder on the bowl jets and Not from the air inlet on our older style CB sohc4's stock carbs. There are other style carbs. on other makes and models(Honda included) which use an enrichener jet rather than a butterfly to restrict.

Yup, and even new non-carbureted cars do it electronically. Point is, choke is used when cold, then comes off when hot.

And yes, SlayedSaint, as Flybox said, note the butterfly's position when you move the choke lever around so you know how and when the choke is engaged.


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1978 Honda CB550K

[theslayedsaint]

Ok i've got the choke down, easy enough to understand, made sense to me when i thought about it. however what doesn't make sense is why i can't get the bike running right or really at all with using the choke. have to start the bike with the choke off,  guessing it has something to do with getting enough air pulled though the carbs? could that be a mixing issue? honestly its hard for me to tell if its running "right", to me it doesn't sound solid and the idle jumps to much for my liking, but then again the only other bike I have like this is a  1971 BMW R60/5 and it runs like a champ for a small engine. so i'm having a hard time just knowing what to except from this machine. guess i'll keep flighting with it and hopefully get it right before summer. 

[flybox1]

how often and when are you adjusting your idle set screw?

[theslayedsaint]

think i was doing it wrong, thought it should idle around 700-1000 rpms, sounds like thats a little low from what others had said? so i'll reset when i can get this damn acewell gauge set right and try setting it around 1000-1500 and after the bike warms up.

[flybox1]

New, out of the box, in perfect tune, with the right gas. . . yeah, it'd probably idle well at or below 1000.
Both my K1 and F3 750 engines idle(d) best at 1200-1300

[theslayedsaint]

Speaking of gas! You guys use high grade 93 or whatever is highest where you live?

[flybox1]

lowest possible octane...and ethanol free if im nearby the only station in my area that carries it   

[grcamna2]

lowest possible octane...and ethanol free if im nearby the only station in my area that carries it   

it sure makes a world of difference if you don't ride your bike everyday;nothing like that ethanol free gas 

[flybox1]

lowest possible octane...and ethanol free if im nearby the only station in my area that carries it   

it sure makes a world of difference if you don't ride your bike everyday;nothing like that ethanol free gas 

+1 
one just 5 miles from me.   

[DaveBarbier]

lowest possible octane...and ethanol free if im nearby the only station in my area that carries it   

it sure makes a world of difference if you don't ride your bike everyday;nothing like that ethanol free gas 

+1 
one just 5 miles from me.   

Don't want to hijack but might as well since the answer is almost right here. The only ethanol free gas is about 30 minutes away from me but it's 94 octane. Which is better, the proper octane or lack of ethanol?


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1978 Honda CB550K

[theslayedsaint]

Ohh! So your saying use lower octane? Interesting. Would love to know why.  Obviously I understand the ethanol part.

[eigenvector]

Compression ratio.

Higher compression engines need the higher octane gas, the Honda inline 4's aren't high enough to need it.  The higher octane gas won't help you, so you might as well save your money.

There are plenty of higher compression engines that need it.  My, now traded, Tiger 1050 ran 12:1 engine compression, I think the Honda is 9.5:1

[grcamna2]

Lower octane like 87-89 will be better performance-wise also for our lower(9:1-10.25:1..somewhere like that..) compression ratio engines;the fuel will ignite quicker w/ better throttle response when properly tuned.

[DaveBarbier]

lowest possible octane...and ethanol free if im nearby the only station in my area that carries it   

it sure makes a world of difference if you don't ride your bike everyday;nothing like that ethanol free gas 

+1 
one just 5 miles from me.   

Don't want to hijack but might as well since the answer is almost right here. The only ethanol free gas is about 30 minutes away from me but it's 94 octane. Which is better, the proper octane or lack of ethanol?


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1978 Honda CB550K

Bump for above question? And also, it's strange, I told my friend who has a Harley Super Glide about this and then I called Harley to see what they say. They said to always use the highest you can get. The compression ratio is only 9.2:1, though. Strange they'd say that. People still think that higher octane means better quality gas.


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1978 Honda CB550K