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Discussion Starter #1
Well, got my new vaccuum pistons in, and she seems to run a little better. Only problem I'm having is the bike bogging out at about 4000 rpm. My friend said I'm running lean, since it seems to run better past 4000 with the choke half closed, but if I do that, the idle will stay high. I'm not really one to fart too much with carb settings, could I just be running to lean?

Thanks!
 

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Sensei
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What jets are in the carbs (primary and secondary mains)?.... I assume you did clean the carbs?.... Sounds like the secondarys are clogged.......Have you "read" the plugs?
 

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Discussion Starter #3
No idea, No and No. Never taken apart a carb in my life. It didn't bog before when I had the torn vacuum pistons in it, that's what I don't get. I know I probably sound stupid, but is it hard to clean the carbs? I've looked at tutorials, video, etc. and it seems like something I can do, just afraid I'll screw it up. Carbs are so finiky it seems and I'd hate to ruin them or make them worse. I guess I'll have to bite the bullet and try it I suppose....
 

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Sensei
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That's Ok...We all have a first time doing any task..... It isn't particularly hard, but you do have to pay attention to details, and it's best to do one at a time (hard on the co-joined 360 carbs, but not impossible)..... If you do decide to do it yourself, there are several experienced 360 owners here as well as some professional bike mechanics...We'll try to guide you through it... take lots of pics and ask questions before you take any step you are unsure of....
If you still do NOT feel comfortable doing the carbs, find a reputable mechanic to do it for you, It likely would be cheaper than replacing a damaged carb, but nowhere near as satisfying as fixing it yourself.......
 

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I say go for it mate! Get yer camera out and a big pot of coffee and the reference manuals and give your brain a floggin'. You feel better for it I swear, and feel free to ask anything :cool:
 

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Discussion Starter #6
Well, looking at the service manual it doesn't look too bad. Are the jets literally like stubby small screws with a hole dow the center? Always thought there'd be more to them then that. Can I use spray carb cleaner, or is there something else I should get?
 

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well the ends of the jets are like short screws. there are more inside (under them) called jet tubes or such. spray cleaner will work but do you have compressed air to blow through them?
 

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Discussion Starter #8
yea, I've got a pancake compressor with a air gun, so I can use that.
 

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Discussion Starter #9
It still seems like its sticking at RPM's too, like when the vaccuum pistons were ripped...Is that a cause of dirty carbs as well? Also, my right side exhuast valve seems to be making more noise than usual, do I need to adjust them again, or did I break something....crap.
 

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Discussion Starter #10
Well I pulled both plugs and one was light brown, which is good, and the other was black and a little wet. The carbs were tuned for the old vaccuum pistons, which were ripped, so I was assuming they running rich, possibly. I changed the plugs and it ran a bit better, but at 3/4 choke it runs awesome, goes all the way to 9-10000 rpm no problem, but then won't drop past 3000, obviously, because it's almost choked. So I'm hopin when I get around to cleanin' the carbs she'll be all good to go. Should I be concerned about the wetness on the plug, or was it just fouled and not burning fuel...I think I'm gonna check the clearances on the tappets again, just to be safe.

Thanks for all the help so far guys!

Oh yea, here's a pic...

 

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Sensei
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Ok...You have an issue.... Choking the carb (even 3/4 choke) is equivalent to making the fuel mixture RICHER..... Yet you say it runs well (to 10K) at 3/4 choke....
One of your plugs shows proper color and the other is wet... This is either from running it choked, or a spark/timing issue... Either way, one of the carbs is misadjusted or needing cleaning, and/or you have an air leak to one cylinder....
You should check the timing as well....... Your valves are fine if it didn't detonate at 10K unladen......
 

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Discussion Starter #12
Where would I have an air leak in the cylinder? Is there a bolt/screw/boot/etc. that would be loose? I'm hoping the carbs just need to be cleaned....It didn't bog or need the choke to run above 4000 rpm before I put the new vaccuum pistons in, I'm puzzled.
 

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Sensei
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Could be where the carbs clamp on, or those "boots" could be cracked, or something similar..... Hard to tell without observation.....
Was that plug brown AFTER running it choked?...If so, that's the side with the air leak.
Are the carbs synched?
 

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Discussion Starter #14
Where it comes off of the air box, the boots are just on the carb, there's no clamp, on either side. I just noticed that today, but figured it was normal since both sides didn't have it, should there be clamps? Not sure if the plug was brown while running the choke, it's the same plugs I've had in it since I replaced them the first day i got it a month ago. I haven't synched them, I didn't know you could synch the CJ360 carbs, they have a different linkage then I've seen on most tutorials/videos. There's only one flapper, not one per carb, so I think to do it right, I would need a vaccuum gauge, which I don't have....
 

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Sensei
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NOT the "hoses" from the air box to the carbs.... The ones from the carbs to the head are the "boots" I referred to..... ( Intake manifold ).....However, a leak in these intakes usually causes uncontrolled revving......
What symptoms does the bike display other than running better partially choked?
(Which tends to indicate a/some clogging in the jets)
 

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Discussion Starter #16
That's really the only issue. It revs up fine when it's in neutral and I goose it. It idles at 1200 and will sometimes bounce to 1000 or 1400, but nothing extreme. I did notice it making like "air noises" I'll call them, from the exhaust, like it was either back firing, or just not igniting. Once I replaced the plug, it hasn't done it since. So I assumed that was a fouled plug mis-firing every once and a while. The only issue is the bogging past 4k when I try to open her up. I guess I will just have to clean the carbs and see! Not sure what else it could be.
 

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Discussion Starter #17
Well, I bit the bullet, rebuilt the carbs, which wasn't too bad. It doesn't bog at all, has a little hesitation between 5k-6k, but very little. Both plugs are now light brown, so thats a plus. It still will stick at about 2.5k-3k rpms after running for a little bit and takes a while for it to drop, sometimes it won't even drop at all until i blip the throttle. Not sure what else to do?! Only thing I haven't done is set the timing or synched the carbs, which I can only do with vaccuum gauges on this one I believe....
 

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Sensei
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The "hesitation" at 5/6K may be cured when you sync the carbs.... The "hanging" at 2500/3000 is likely the advance mechanism sticking a bit.....You can check/clean/lube that when you time the bike.........
All in all, sounds like you are making good progress......
 

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Discussion Starter #19
I bought a tune-up kit, because it was only 4 more dollars than the condenser alone. So I'll put the new points on when I time it and lube it. Hopefully I'm almost there!
 

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Discussion Starter #20
Haven't had a chance to time the bike yet, busy work week(s), but I did take the timing cover off tot ake a look at the plate and points. Believe it or not, these things look brand new. No oil, grease, anything. The metal is still that shiny yellowish color. Is it possible, the guy before me replaced the whole timing plate and points to get the bike to start but never timed it...and it not being timed correctly would cause my hang up issue? The advance unit wasn't hanging up at all, still looked good and the weights snapped right back when I extended them. But if the bike is timed horribly (or never been timed), would that cause any of my issues so far?
 
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