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the one positive thing I can say about the DOHC carbs is that they had a better idle circuit and choke than the SOHC predecessor. My 1975 750 you have to hold the throttle when cold just to keep it running no matter what, but my brother's 1979 750F will just sit there idling on choke. If it is below 50 it will stall once or twice, but otherwise that thing just ticks over like it's no big deal. Of course the carbs are terribly designed everywhere else so....there is no making up for that, but at least they idle nicely.
 

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Discussion Starter #42
Been a bit since I've been on the forum here, busy with work and camping.

Discovered that my excessive back-pop issue is due to bad gas, or at least gas that my bike really does not like.

Tried to adjust the timing chain tensioners. Was able to adjust the front bolt easy enough, and the rear top acorn nut kind of. I was unable to loosen the rear-bottom acorn nut without fear of rounding it off. I have not heard the piston slap noise that Geeto mentioned that I watch out for, but now I am getting what sounds like a slight loose chain slap when I decelerate in gear. With my helmet on it is difficult to tell if it is coming from the engine or my drive chain. Of course the V&H exhaust does not help the being able to hear much. I am considering taking it in to the local Honda dealer to have them adjust the timing chain, but I'd rather avoid that fee if I can.

On the plus side, when I opened the the stater case to turn the engine over as I adjusted, I was pleasantly surprised to find it looking fairly fresh and new, no cracking in the epoxy around the copper, mags and brushes and such all seemed in good shape and hardly used or aged, must be newer lol.

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Is those 2 carbon contacts that will eventually wear out and then your electrical will simply quit.

... your bike has a chain primary drive does it not? That is what will induce drive lurch when you go from acceleration to deceleration.
 

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Discussion Starter #44
Is those 2 carbon contacts that will eventually wear out and then your electrical will simply quit.

... your bike has a chain primary drive does it not? That is what will induce drive lurch when you go from acceleration to deceleration.
That is my first thought. I need to lube the chain again and maybe tighten it up
 

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That is my first thought. I need to lube the chain again and maybe tighten it up
Is it a sealed chain? You just clean it and put enough rust preventive coating on the outside to stop it from rusting,
don't over-tighten the final drive chain, that is catastrophic.

... go down big hill, pull in clutch and drop to idle, listen to chain noise,
maybe coast under a bridge or in tunnel, don't break the law or get killed doing it.
oh wait Idaho :| nope, no idea.
 

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Discussion Starter #46
I've only ever owned chain drive, other than my 02' Sportster. Have not over tightened a drive chain yet and don't plan to start now lol. Ive got some good lube/anti rust stuff that I will try. Supposed to be thunderstorms for the next 2 days so i will have time to give it a try
 

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Sounds like a typical air cooled motor ;) or bag of hammers.

Put it gear with the motor turned off roll forward, now roll backward, now roll forward, now roll backward :| are we hearing any chain clunk?
seeing a lot of backlash travel from the crank to the rear wheel?
If yes we have a bagged out primary drive or something else like the rubber rear cushion drive, you are looking specifically for play inside the engine for it to be the primary drive.
 

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Discussion Starter #49
I will try that out. Thanks for the advice
 

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Discussion Starter #50
Tightened the drive chain this weekend and swapped the oil. No chain slap noise yet, well a tiny tiny bit, so I may need to adjust the chain a tad more and call it good. But other than that everything seems to be running as smooth as can be expected from a 36 year old motorcycle
 

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Discussion Starter #51
I have found that the thing I love best about this bike so far is a small thing really. When the RPM's are up and I am accelerating to hwy speeds, the engine makes this little whine, mechanical sounding, almost like a turbo spooling up. To me it is among the most satisfying sounds in the world. I am fast falling in love with inline 4's
 
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But they are very wide in the hips so prone to drag hard parts in tight or bumpy corners, be careful of that once you start riding it more aggressive.
 

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Discussion Starter #53
But they are very wide in the hips so prone to drag hard parts in tight or bumpy corners, be careful of that once you start riding it more aggressive.
I do not intend to ever get that aggressive on this bike. Mostly because I do not want to risk damaging it, it's to damn pretty lol.

I did go for a ride this weekend and found out that the bike is still capable of hitting it's limits set forth by Honda from when it rolled off the factory line. Possibly more, but I did not test it that far.
 

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But they are very wide in the hips so prone to drag hard parts in tight or bumpy corners, be careful of that once you start riding it more aggressive.

so what you are saying is....it's a honda...
 

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Remember riding pillion on one of the first CB750's, in almost every corner I had to lift my foot off the inside passenger peg, because I knew it was going to hit the ground and flip up anyway.
My CB350-4 was nicknamed sparky :| All early Honda I-4's are prone to drag hard parts in the corners as I recall. ymmv. We always rode fairly aggressive.
 

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Discussion Starter #56
So this guy at the UPS depot across the street from my work got a new bike this weekend. He is usually on a BMW GS650 (I think) but scored this beaut from his brother in law and parked behind me.

1983 CB400
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Discussion Starter #58
cb450, the baby supersport. nice.
That's what I thought, guy said its a CB400N. Still a nice bike no matter what it is. Half tempted to see if he wants to let me buy it for my wife.
 

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That's what I thought, guy said its a CB400N. Still a nice bike no matter what it is. Half tempted to see if he wants to let me buy it for my wife.
CB400N would be a super dream. I think we only got them in the US for 1 or 2 (79-80) years before the cb450T took over (81-82). It could also be a canadian import, though it looks like it has the 1979 graphics that mimic the US cb750F 1979 graphics.
 

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Discussion Starter #60
If I see it again today i will ask more
 
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