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New (to me!) '77 CB400F - US model
Nurse Julie:
--- Quote from: mattsz on March 10, 2019, 04:00:35 PM ---
--- Quote from: mattsz on March 08, 2019, 12:46:43 AM --- How much re-tightening torque are we talking about here?
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--- Quote from: Nurse Julie on March 08, 2019, 08:53:27 AM ---There is no torque, its automatic spring tension that enables the process of adjusting the chain. You only undo the lock nut and adjuster bolt to allow free movement of the chain tensioner adjuster bar to allow the springs to push the chain tensioner adjuster bar to be pushed down further on to the horse shoe, which in turn, pushes the tensioner slipper on to the chain to take up the slack. It's an automatic tensioner. But for the process to work and remove any cam chain rattle from a slack chain, the chain must still be within service limit, the horse shoe pivot not seized and the spring not weak. As Bryan says, worry not now, sort it out at a later date if needed.
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--- Quote from: mattsz on March 08, 2019, 05:09:05 PM ---We may be talking semantics here. Since there is a locking nut, I figured that the adjuster wasn't relying on torque alone to hold it in place, but the manual does say to re-tighten it, and to my mind that means some kind of torque - even if the intent is only to tighten it just until resistance is felt. The answer to "how tight should it be?" is a torque value, isn't it? The manual reveals nothing on this score...
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From Haynes - "Turn it again inwards, until slight resistance is felt, then re-tighten the locknut."
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Yes, after you have released the lock nut and washer and the chain has self tensioned. You do not tighten the bolt and lick nut to achieve tension, you loosen it, which achieves tension via the springs.The tension they are talking about is the bolt on the arm.
mattsz:
--- Quote from: Nurse Julie on March 10, 2019, 04:18:16 PM ---Yes, after you have released the lick nut and washer and the chain has self tensioned. You do not tighten the bolt and lick nut to achieve tension, you loosen it, which achieves tension via the springs.
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Understood - it was the very non-specific "re-tighten" instruction in the manual that had me wondering, is all...
Nurse Julie:
--- Quote from: mattsz on March 10, 2019, 04:20:34 PM ---
--- Quote from: Nurse Julie on March 10, 2019, 04:18:16 PM ---Yes, after you have released the lick nut and washer and the chain has self tensioned. You do not tighten the bolt and lick nut to achieve tension, you loosen it, which achieves tension via the springs.
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Understood - it was the very non-specific "re-tighten" instruction in the manual that had me wondering, is all...
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It doesn't need to be any more specific really, you are only doing up what you undone previously, if you get my drift.
mattsz:
I can't be certain, but I think I may hold the record here for keeping the longest thread running without actually doing anything. Just saying... :-[ ::)
I do wish I had the bike in my own garage, it sure would make it easier to sort through some of these things...
I'm wondering about whether the bike was dropped, or had some sort of accident, based on the condition (three years ago) of the shift lever (bent), the left rear turn signal (bent), and the rear fender (broken).
When I first saw the bike three years ago, it looked like this:
And the fender looked like this when it arrived, with the tail light's upper right-side mounting point broken, but that's obviously not recent, either (the rest of these pics can be zoomed in by clicking):
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That underside mounting plate is broken in two, and some of the spot welds have parted as well, so the closer portion is free to turn when you try to remove the tail light.
I can't remember if that left rear signal was bent but secure, or just loose - either way, when I got the bike, the signal was more or less straight. When I removed it, I found an extra (locking!) washer in the stack of mounting hardware, which was cranked so tight I thought for sure I was going to break something trying to loosen it. The fender damage seems like it could be from vibration, although I haven't heard of this problem on these bikes, or maybe the light fixture could have been struck to cause the break. The bent shift lever speaks for itself - but there is no other sign of impact damage, and these parts show no other scuffs or scrapes which you'd expect to see.
Turn Signal:
Here's a photo I just took of the signal brackets. You can guess which one is the left one!
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I'm hopeful that I can bend it back to "normal" and go back to the correct mounting hardware and it will be right - and that the frame at the mounting point isn't bent as well. But in the photo you can see that even the right side bracket has a bit of a curve - did that get bent over time, or is it supposed to be that way, anybody know?
Fender:
I had to get a bit rough with the broken mounting plate, as it turned with the mounting bolt and had clear intentions of shearing the wiring. I'm not even sure where all the broken pieces of the fender are:
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I'm keeping an eye out for a used replacement in reasonable condition - I just don't want to spend top dollar on a brand new one, which will look out of place with the rest of the bike's patina. I've heard, I think, that a 350 fender would fit, too - there seem to be more of them on ebay, but they all have four tail light mounting points, while the 400's all seem to have three mounting points. Some I'm seeing for sale include the tail light, so that could work - or I could just drill a hole.
If I can't find a replacement, I may just knock out a new mounting plate, wide enough for a couple of extra bolts to hold the tail light to the fender - four in line instead of just the two at the top of the tail light bracket...
mattsz:
No takers on the turn signal brackets?
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