Topic: What does it indicate if the bike runs great but is a PITA to start?

[juntjoo]

As some of you'll have already gathered from my other thread I'm having electrical issues with an intermittent weak start. But it wouldn't be so bad if the bike would just start promptly. And so after it does it idles and accelerates and runs great as it always has but always has had this issue with starting up. From your more experienced perspectives and understanding how these engines and engines in general work, what would this indicate?  I'm hoping one of you has a good idea but afraid I'll get multitude of possibilities. What do ya say?

[evinrude7]

There is no magic bullet to electrical issues in my opinion. It's work tracing down the issue. Asking specific questions. Studying the wiring diagram.

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[PeWe]

My stock K6 carbs need experience.
I have reused them on my stock K2.
Reinvented how it want to be started, much throttle and 2/3 choke, let it idle, reduce to 1/2.

After riding a few minutes it need 1/3 choke for an addirional 10 minutes.
Easy to forget choke, visible when increasing throttles higher than the choke device in carbs.

If not been started for a while, full choke for some revs before the final start attempt.

Mikuni carbs have a better choke circuit. VM29 and TMR32.

[juntjoo]

Hmm... Yeah.. I'm thinking a fresh set of plugs to start.

But, right off the bat, to start if from just sitting, what is the magic formula? Idle and main circuits gotta be free? I'd have to guess my idle ones are good after all the cleaning I've done. I know my accelerator pump works cuz I see a little fuel after pumping it. My plugs are a bit wet and I think that's from the pumping. So somewhere between the spark and the fuel from start/no motion is where I'm at I guess. I've always had spark and enough to have it run fine as far as I can tell, but maybe new plugs will have even better spark needed for initial starting? This idk as I don't recall last time I ever changed plugs to solve a start issue in car in my life. This is my first and only bike.

I've read something in the manual about "cold" and "hot" plugs. I'm not clear on that.

What should I get as far as temp in plugs? Cb650sc in SWFL. any suggestions?

[evinrude7]

I get a little bit crisper start with denso plugs than the ngk

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[evinrude7]

juntjoo, what kind of points are on that bike?  brand?

edit: i see you have a pulse generator.  can that be tested?

[juntjoo]

I get a little bit crisper start with denso plugs than the ngk

Thanks. Looks like an online order...

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[juntjoo]

juntjoo, what kind of points are on that bike?  brand?

edit: i see you have a pulse generator.  can that be tested?

Dude, I don't even k ow what you're talking about lol. Can you help me out a bit. I got a Lotta tools but little knowledge

[juntjoo]

I'm out on my bi sickle about to hopefully find some plugs in an open box so I can return em if they make no difference

[juntjoo]

I get a little bit crisper start with denso plugs than the ngk

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Local store here is pulling these up as ngk also, denso & ngk as same plug. Two types, all the same except "center electrode" copper on one and and "standard" the other. Same price. I'm thinking they're identical

[PeWe]

NGK D8EA look different than Denso X24ES-U.
Ground strap and isolator differ very much.
Not same plug.
Use either of them, same for all cylinders.
A new plug should not have start issues.

I have used them both.

[juntjoo]

NGK D8EA look different than Denso X24ES-U.
Ground strap and isolator differ very much.
Not same plug.
Use either of them, same for all cylinders.
A new plug should not have start issues.

I have used them both.

I just ordered some "iridium" ones. Supposed to last longer and maybe perform better?

[evinrude7]

juntjoo, what kind of points are on that bike?  brand?

edit: i see you have a pulse generator.  can that be tested?

Dude, I don't even k ow what you're talking about lol. Can you help me out a bit. I got a Lotta tools but little knowledge

https://www.cmsnl.com/honda-cb650-1982-c-usa_model7225/partslist/E++06.html#.X9_CKxZMHIU

[evinrude7]

NGK D8EA look different than Denso X24ES-U.
Ground strap and isolator differ very much.
Not same plug.
Use either of them, same for all cylinders.
A new plug should not have start issues.

I have used them both.

I just ordered some "iridium" ones. Supposed to last longer and maybe perform better?

stick with recommended stock plugs. 

[goodtryer]

Are you sure the choke is closing fully?

[PeWe]

Irridium not better. They ran as a colder plug in my CB750.
Stay with stock type.

[Scott S]

 Your carbs have an accelerator pump that squirts a little gas into the throat of the carbs. The passages are VERY tiny and hard to clean. There's also a rubber diaphragm and rod on the little pump. If that's not all clean and set up right, it can be hard to start.

 Plus, you're dealing with the broken pin on your advance mechanism, which can and will alter timing.

 Are you still running that hokey homemade intake system with the hoses and such?

[PeWe]

+3 carb issue(s)

[754]

If it runs fine warm, and has starting problems it's usually carbs.
 No sparkplug juju will fix that..
 Average number of times carbs get cleaned before getting it right. .. on here for most that haven't done it before ,  is 3 times or more..
 That is telling something.

[madmtnmotors]

I'm with 754 on this. Try a shot of starter fluid on cold start. If it fires right up then carbs need attention.

[evinrude7]

Thought I recall him saying wet plugs. Bad battery, old plugs leads me down electrical path. He said he's never changed the plugs on it. Doesn't know what kind of ignition system he has either.

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[754]

Wel, if he wont change plugs......... that is not good....

[juntjoo]

Are you sure the choke is closing fully?

Yes

[juntjoo]

Your carbs have an accelerator pump that squirts a little gas into the throat of the carbs. The passages are VERY tiny and hard to clean. There's also a rubber diaphragm and rod on the little pump. If that's not all clean and set up right, it can be hard to start.

 Plus, you're dealing with the broken pin on your advance mechanism, which can and will alter timing.

 Are you still running that hokey homemade intake system with the hoses and such?

I just have the carbs open with tape covering half the opening as before. I've always had a hard start issue even with the air box. Never changed the plugs so I'm gonna give that a shot. I'll do standard as suggested. You guys say stock as in these bikes have a particular brand/type recommended? I'm gonna go with what auto zone has which is the ngk/desno.

My repair on the advance unit feels pretty solid. I hope. I cut a dremel bit to a longer length so it wouldn't keep falling in the hole as it was.

My accel pump works good. I see fuel coming out of the carbs. About to have the battery tested...

[juntjoo]

... carbs get cleaned before getting it right. .. on here for most that haven't done it before ,  is 3 times or more..
 That is telling something.

Huh? You read drunk lol. Are you saying most people have had to clean out their carbs several times to fix issues? That's not good news. I've cleaned these a couple times already. Between each cleaning bike sat for like 8 months.

What could I have missed? I did the two Jets. Can see right through both. Also the pilot(air) screws. Accel pump works good. Carb spray didn't help this time. A year ago that's how I had to get home at night, carb spray. Always had this hard start issue. Otherwise bike always ran good. In my garage couple days ago ran (stationary) strong. So only difference now is carb spray no work. So I'm hoping new plugs will do the trick although you guys are betting not.