Topic: CB400f Camchain Woes

[CBGBs]

I've owned the bike for many years and the cam chain has always sounded bad however when I finally got tired of it I sent it to a pro. When I got the bike back the chain sounded much tighter, almost too tight but I can only really compare to too loose. It held for only a few rides then on a warmup it slipped and went back to noisy. I am using a TTR adjuster bolt and when I tried to adjust it, it made no real difference as if it were bottomed out with no more adjustment. I pulled the engine to find the U-shaped piece was still free and although one blade was very worn, the system seemed to be operational except that the plunger was fully seated into its bushing so that there was no more adjustment to the system. I don't know what to do except change the chain and blades again and hope something is different. Any suggestions?

[Mark1976]

   Just my 2 cents.
If the adjustment was all used up, the adjuster plunger wouldn't be bottomed out. It may be stuck in its bore by the locking bolt. If its been run loose for any prolonged period of time the rear blade will sustain an excessive amount of wear, particularly on the lower half. If the chain were too tight, it'll whine (howl like you can't imagine at speed). Post some pic's...

[jonda500]

+1 if the adjustment plunger is "bottomed out" that is the backed off or loosest position. It should have a spring that pushes it into the U piece when you undo the locknut and loosen the adjuster bolt. What is a TTR adjuster???
John

[bryanj]

The flat on the adjuster gets marked up by the pinch bolt and frequently gets pulled back to a previous position, do you mean the plunger was all the way extended(out) in which case chain was worn out

[CBGBs]

The TTR adjuster replaces the top bolt with one that will drive down to the plunger rod and make a 'manual' adjustment as opposed to relying on the force of the springs. When I say it was bottomed out, I mean it was at the max adjustment that could be reach with this setup. The top screw was extended to contact the bottom of the cavity. All I can do is to put on a new chain but I believe this chain has only a couple thousand miles on it. One of the blades was quite worn. Any specs on cam chain stretch? I don't trust the TTR adjuster or the springs.

[Tim2005]

The blade wear is mostprobably your main problem, using those type of tensioners makes it too easy to overtighten the chain and cause that to happen, then once the blade wears it makes the chain very slack. Get yourself a new blade, that's essential (and quite expensive, alas). As it has been overtightened fit a new chain too (they aren't all that expensive). If your springs need replacing these are the part numbers, a quick google suggests a few are around NOS still. Fit those then all should be fine and I would suggest you chuck the manual tensioner in the bin.
14543-333-000 SPRING, TENSIONER INNER................
14541- 333-020 SPRING, TENSI0NER OUTER . . .. .... . . .. . ...

[CBGBs]

Sounds like a good plan Tim and thanks for including the spring numbers.
I've not had any luck with tracking down the springs. None on EBay, none on DSS. Discontinued and out of stock everywhere I see.

[Tim2005]

Yes, I had a look and they are very hard to find. This place has the outer one, but I can't find the inner one in stock anywhere. How long is your inner one? Generally springs get shorter as they age.  New they are 41.5mm.

https://www.ebay.com/itm/163838003497

[CBGBs]

My inner spring measures 38.8mm. Maybe I could shim it?

[Tim2005]

I don't think shimming would make much difference. I just measured all my used ones, they are all around 39mm and the outers are 50mm, (52 new) and I've kept them to re-use them sometime. Is your outer similar length? 

[scottly]

I seem to recall reading about putting a spacer of some sort at the top of one of the blades??

[bryanj]

DO NOT fit spacers or you risk a broken blade

[CBGBs]

Outer is 50mm. I was thinking a 2mm shim on the spring may help.

[Rick4004]

I have used the manual style adjuster for quite a few years now. You can adjust the tension while the bike is running. You can loosen/tighten  the adjuster and hear when the cam chain noise just goes away, and leave it there. Tighten it too much and you can hear a strained whirring noise.