CB200 restoration

[bluejets]

Latest February 2023, going together nicely.
Currently working on electrics which can be daunting as there are UK, USA, French,European versions but Aus seems to get a right mix.
So went back to basic logic, works for me.
72 yesterday, need to get the finger out.........

[bluejets]

Engine run today......brainfreeze with the choke, fully up is choke on.....DOHHHH!!!!!!!

Other than that, must remember ignition kill switch, one float needle was stuck in the closed position....all other ok.

After market mufflers give it a rather savage rumble ....... today's effort will be to check valve timing and cam chain tension then good to go.

Short vid here.....

[_AL_]

Looks super clean.
Very nice.

[Wayne_H]

Engine run today............

and cam chain tension then good to go.

Short vid here..... https://www.youtube.com/shorts/X52AvZtfZbg

Noice one Jeff.
Luv the Aussie safety boots

[bluejets]

Thanks.....Thongs ok for "down in the shed at home"....definetely NOT when riding (although have seen it many times)

Had what I thought was a battery charging issue on the bike but after checking all through the system, all seemed ok.
Watched a video from a Youtube site and today confirmed that indeed, revs in the range of between 3,500 and 5000 necessary to get the 13.6v PD.
Who would have guessed.
I had been testing around the 1500 mark and barely arrived at 12.3V, so there ya go.
Many have said these models have a rather weak gen system and it appears so.

Making arrangements with my younger brother to tig up a couple of extra muffer baffels, these after market units are just a little too loud for my liking.
I like to give a bike a quick squirt now and again without attracting the attention of the local constabulary.

[bluejets]

As can happen from time to time, just as one gets comfy, something comes along and bites on the butt.
Ran the bike outside for some road tests but it was difficult to get it to drive under load in low gear, others not too bad.

Engine to come out again was the only route.
Found the selectors were bent , among a couple of other things so in bits agin until I get the ordered spares.

https://www.youtube.com/watch?v=bNNB1q3psA0

[stormer254]

I feel your pain, I have a 72 Bultaco Alpina, thought it had rumbling mains, put it back together, same noise, 6 years later I am still trying to build up the enthusiasm to split the motor again!

[bluejets]

Back in the early 70's we all had Triumph or BSA.
Mate had bought a South Aus ex-cop bike (A65) beautiful compared to the pre-unit models.
We split it looking for what appeared to be a big end rattle, crank sludge cleaned out, new bearings, rings etc later, still the same, rather a disappointment.
We were certain we had missed something.
Went to go on a ride to Brisbane weeks later after refit and headlights wouldn't work when motor shut down.
Long and short of it, these engines had the first of the alternators fitted, found battery was knackered and completely dry.
Fitted a new battery, checked charging etc which was good, voila, no more bottom end noise.
Origin was apparently the alternator loading up due to the "shorted knackered battery".

As for the CB200, currently going back together after replacing the bent first gear selector. Fitting new gaskets, rings and seals on the go.
Biggest hurdle was getting spares at a "reasonable cost". No such thing in Aus, especially not from the US given their extreme shipping rates, UK not all that much different. Managed to get from a bloke in Canada. Mention CB200 anywhere and the price of similar parts compared different Honda models and the price goes up anywhere between 2 to 4 times more.

Intend to sell it when I get it all smickey, cost of rego and insurance here lately (amongst other things)has made everything impossibly expensive.
Can we send you an Albo..???(free).....we are sick to the back teeth of the dopey boofhead and his mates here.

[bluejets]

Engine back in again just waiting for some carb inlet orings.
Found a bent gear selector and other spare engine had good part so basic swap over.

Major job though and while it was out, new rings (standard bore) all new oil seals (most obtained online at various places) new timing chain and complete gasket set.
Rings and gasket set came from Canada at a rather surprisingly low shipping cost. He did mention though, if i had added say some carby gaskets and needles, the shipping became ridiculous. (go figure)

Mention anything to do with motorcycles online say, Ebay, and mostly parts can be found. However, tag the search with the words 1974 Honda CB200 and price of similar parts goes up by a factor of perhaps 5 or 6. Seals for these mothers can be a headache as they use odd sizes, like 37.5 x 20 x 4.5
Mostly they are available aftermarket like i say, but for others one has to make a compromise. Aliexpress seems to cover most. Some would say, oh cheap Chinese crap, however, the original seals for Honda were supplied by the same Chinese manufacturer way back in the 70's.

Final drive sprocket was a bit loose on the output shaft, not in the sprocket itself (one has to wonder why they do it this way) but on the shaft. Sprocket inner only covers slightly more than 50% of the available spline, other section never used.

So found an old sprocket (hard as the knobs of hell) marked out and ground away most of the outer section and epoxied this to the back side of the good sprocket I already had.
When applying the epoxy, outer(good) was turned on the spline so it took up the slack(just). After epoxy cured, clamped all up in the vice and welded the newly ground section to the back of the good sprocket. Had to dremel grind a small angle to the back of the newly ground spline to allow the whole assembly to go back(maybe additional 30 thou) to allow the front keeper to fit the provided slot.

Brilliant job, nice and firm again, better than new I'd have to say.

[bluejets]

After all the restoration work above, spent a couple of months trying to work out why engine was sooting up the plugs and running upta sh**t on idle.(HAD to be rich)
Would fit new plugs and engine would run fine for a couple of minutes (from cold) ....(Note:point to come back to as it turned out to be important)

After warm up, would stammer and eventually quit.
Must have checked ignition timing, points (new) coils, leads, valve timing and clearances, voltage drop to coil, battery voltage, wiring, condensor, fuel jet sizes, both idle and mains, exhaust system,all a dozen times.

Checked recommended fuel levels 3 or 4 times, nope, all good.
Then one sesson, turned off the fuel cock with engine running and after maybe 20 seconds, ran like a dream.

Ahh..ha..so....made up fuel level indicator tubes from clear plastic, made up some nozzles from plastic bottle tapered tops and screwed the assemblies into the float bowl drain screw hole. With the tube retained above top of bowl, turned on the fuel cocks and marked the level on the bowl exterior.
Then turned off the fuel cock.
Then ran the engine on idle until it ran smooth and marked that level on the bowl exterior for each carbie as well. Turned out to be almost 4mm lower.

Now a change of jets may be the answer but one would have to wonder why it would change from recommended size. Perhaps someone in days gone by had cleaned out with a stiff wire or a drill bit, who knows, I certainly knew better not to do that. Had no way to measure the size short of running a drill bit through myself.

So fix was to drop the floats down by the 4mm amount.
Now back to why it ran ok when cold....all engines need a rich mixture when cold. Failed to mention choke was never necessary to start....as I said, it now became obvious as to why.
Final prognosis is a new set of idle jets and reset floats back to original would be a start for a new day, however, it's quite ok as it is now, top end is fine etc.
Can tell you it was a real headscratcher and a lesson in diagnosis. Not difficult to become waylaid on an entirely wrong direction in thinking.

One good outcome from all the above, my old mate George Punter has been having difficulty with a 125 4t Benelli he bought and he is having similar problems. Almost brand new and with a brand new complete engine. Turns out to be an "end of production" model and appears the factory may have simply thrown whatever bits together to get the bikes out the door.
A bit more to the diagnosis but essentially he is at an end to being able to find the problem and my experience was like a breathe of fresh air. One could see the bits falling into place as he listened to what I had gone through and my final success.