[beestoys]

Thior
The wire should actually has to be twisted into the coil posts. Then the collar is twisted down with the seal placed over the wire. It will look like a wedge shaped piece. It compresses down against the wire wedging in a causing a seal. The spark plug boot does the same thing but it doesn't have the locking collar. what can happen sometines id the plug wire can break up and make the post that engages that wire come loose. You can try twisting the terminal off the wire cutting say about 1/2 inch off and twisting it back on. It's almost like a wood screw thread on the post inside the plug boot. So right twisting inserts it left twisting removes it. As for the spark plugs most arte shipped with the cap on as stated earlier. You will need to remove these ends in order for the plug bot to seat onto the plug and lock. you should feel a series of clicks as the wire clip that is built into the cap slides over those threads. If you don't hear or feel this then you need to take a flashlight and look into the cap and make sire the clip is not damaged. What you should see is a brass or silver collat with 2 wires running next to the hole. Those wires are what engage the threads on the tip of the spark plug.

 

[Aussie Dave]

It looks as if on this cap I'm should use the bigger cap thing on the spark plug. It seems by using the threaded top of the plug, it's not a fit at all to the coil side. I changed plugs yesterday and also fitted a piece which will hold the coil cap down and everything seems smooth now....but today is another day

Ahhh yes, today is another day.... I should have been getting ready to go for an early ride in the cool morning air before it gets too hot and sweaty.... but it was sprinkling with rain when I got out of bed at 4.30am and I was tricked out riding - of course it hasn't rained since, and it's nice and cool....... ....... ah yes, the CBR plug cap mystery.......

How does that plug cap compare to the other three?

Is there a part missing or broken? Is the dust/weather seal in the same position as the other three caps (it may have slipped up the lead)? Make sure any broken bits aren't lying down the shaft beside the spark plug or they might find their way into the cylinder head when the plug is removed (strong light or blow clear with compressor air).

I'd be wary of using one aluminium capped plug when the other three are screw threaded and locked on - there is something not right and a dodgy mod may lead to an ignition spark fault if not sorted now while the bike is apart - it takes so much effort to dig down to the plugs once all the fairings are back on so it's best to fix it properly now rather than have to do it all again later.

Can you snap a pic so we can see inside the plug cap with one of the other caps beside for reference? I'm suspecting a broken locking wire in the cap tip or cracked cap body....... these can be replaced with one scavenged from an old plug cap. While you're at it, measure the electrical resistance across the lead to cap tip when disconnected from the coil. All 4 leads & caps should be similar Ohms.... I think around 5,000 ohms but check the online workshop manual here in the reference section.

Could it be so simple as the rubber dust/weather seal at the top of the long plug holder has slipped out of position and is preventing the cap from locking on?

 

[Thior]

Ahhh yes, today is another day.... I should have been getting ready to go for an early ride in the cool morning air before it gets too hot and sweaty.... but it was sprinkling with rain when I got out of bed at 4.30am and I was tricked out riding - of course it hasn't rained since, and it's nice and cool....... ....... ah yes, the CBR plug cap mystery.......

How does that plug cap compare to the other three?

Is there a part missing or broken? Is the dust/weather seal in the same position as the other three caps (it may have slipped up the lead)? Make sure any broken bits aren't lying down the shaft beside the spark plug or they might find their way into the cylinder head when the plug is removed (strong light or blow clear with compressor air).

I'd be wary of using one aluminium capped plug when the other three are screw threaded and locked on - there is something not right and a dodgy mod may lead to an ignition spark fault if not sorted now while the bike is apart - it takes so much effort to dig down to the plugs once all the fairings are back on so it's best to fix it properly now rather than have to do it all again later.

Can you snap a pic so we can see inside the plug cap with one of the other caps beside for reference? I'm suspecting a broken locking wire in the cap tip or cracked cap body....... these can be replaced with one scavenged from an old plug cap. While you're at it, measure the electrical resistance across the lead to cap tip when disconnected from the coil. All 4 leads & caps should be similar Ohms.... I think around 5,000 ohms but check the online workshop manual here in the reference section.

Could it be so simple as the rubber dust/weather seal at the top of the long plug holder has slipped out of position and is preventing the cap from locking on?

It looks different. The other 3 are narrow with ridges it seems where it grabs the plug. This cylinder one looks like an old lawnmower end. Big fat round thing.

It's running well except still have the knock. It starts about 3000 rpm and goes from there. Clutch has no factor in it or gearing. It doesn't seem to get worse but I don't much get it over 5000rpm anyway.

Finally learned the trick to starting her up. I don't have a diaphragm yet so I have external fuel shutoff.

Bought a new gas cap deal with keys and ignition . None of it worked, key stuck in cap, no key to ignition. Was disappointed. But hey, I'm still happy, 1800$ with 24k miles and runs....I'll take it

 

[Thior]

Still need new plastics, but this is I think going to be the color scheme. She is a bit like Frankenstein's bride right now

 

[fizzy]

Knock from 3000 - 5000rpm? Check the CCT, cam chain and cam chain guide. With that exhaust I am surprised you can hear any engine noises.

"She is a bit like Frankenstein's bride right now " more like a starring role in a mad max movie.

 

[beestoys]

It looks different. The other 3 are narrow with ridges it seems where it grabs the plug. This cylinder one looks like an old lawnmower end. Big fat round thing.
That's the wrong cap then. You'll need to swap it out for the correct one.

Bought a new gas cap deal with keys and ignition . None of it worked, key stuck in cap. If you look at the base of the cap there are 2 big tangs push those in and the key should rotate and release.

 

[Aussie Dave]

Wow, that's a world class 'Rat Bike' as is........ .

You've got a bit of work to do.........

PS That different plug cap must be a 'ring in' from a different model...... gives you a clue as to how mechanically proficient the previous owner's/stealer's were at maintaining the machine. You may need the screw on cap as mentioned earlier...... or a new set of accessory leads and caps (eg NGK or oem Honda if avail at reasonable cost).

One possible thing to check asap is the valve clearances - just in case some have closed up completely and might be letting a valve touch a piston. It will take months of forensic examination to reverse the previous mistreatment and make a Cinderella out of this poor thing........

 

[Thior]

What is your running battery voltage? And battery condition? This problem maybe electrical in nature. Low voltage can affect spark at the plugs. Both stator and rectifier can and do fail on this bike. Running voltage should be 12.5V- 14.5V depending on rpm. . Low voltage would indicate bad stator, bad battery or bad wiring.
Rig up a digital voltmeter so you can observe it while riding.
Also, if the tank has loose rust inside, very small flakes can block carbs (or FI), no amount of chemical cleaner will help. They must be physically removed.

The noise is between 3200 and ..... I really don't get it over 3200. I just cruise around on it. Don't think I've been above 60mph.....but it is what we in the south USA call winter ....60 deg. Cold

 

[Thior]

Wow, that's a world class 'Rat Bike' as is........ .

You've got a bit of work to do.........

PS That different plug cap must be a 'ring in' from a different model...... gives you a clue as to how mechanically proficient the previous owner's/stealer's were at maintaining the machine. You may need the screw on cap as mentioned earlier...... or a new set of accessory leads and caps (eg NGK or oem Honda if avail at reasonable cost).

One possible thing to check asap is the valve clearances - just in case some have closed up completely and might be letting a valve touch a piston. It will take months of forensic examination to reverse the previous mistreatment and make a Cinderella out of this poor thing........

Oh,. I hate doing valves ...I got a 955i RS that is just a pain. Im thinking of taking by Honda just to check out everything. Im a great parts changer, with some diagnostic abilities. I do restoration on cars and such but this is two wheels....something falls off and it's not just coast to the side road.

My 955i ive redone and my mustang restored (just blew motor)

 

[beestoys]

There's a very good chance it's the CCT as mentioned. It's a simple check. Fire the bike on the center stand is best warm it up. Slowly increase rpm to 3000 if it starts rattling slowly increase rpm if it's the CCT it should stop about 4 to 4500 rpm.
If it does the above it's a 30.00 dollar fix and about 30 minutes of you pull the lower fairing or 15 if your careful and don't remove it. It can be dine6this way its just a bit tight. If you remove the infill panel bolt back by your foot and the upper fairing mount bolt by your knee then it gets real easy to work around.

 

[Aussie Dave]

Hold off on the Honda shop 'doing the lot' as I'm almost certain they'll charge you lots and do the least........

Most BB owners that have said to me they "had the shop check their valves" at a service might be shocked to know the work was likely not done, but they would have been invoiced for it........ yours is worth doing as it may not have ever been checked, and it's worth knowing if they are in spec (or not) as part of the restoration.

Sticking a feeler gauge in to verify the valve clearances is time consuming, but not hard if you just work methodically pulling it down from the airbox to the cam cover...... I'd agree changing a shim is another level, as it requires removing camshafts...... but if all else has been checked and the noise is still there, then it is worth measuring and recording the clearances (which I think should be 6 thou inlet and 9 thou exhaust from memory).

There's all sorts of stuff to check....... one I'm getting my head around is the balance shafts....... after 16yrs I have at last read that they can be adjusted if needed....... I didn't know that until I read it here!

Also, badly out of synch motors can bang and chatter a lot at idle, but not usually above 4k rpm....... hence the suspicion of a CCT spring. Sloppy worn chains and sprockets make horrid noises that sound like clunking while riding if you haven't yet eliminated that. You're up against diagnosing the damage done by previous owners so almost anything is possible.......