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CJ250T

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AndyD:
Hi,
Started stripping the CJ to assess condition and plan restoration of the handsome beast.
I just wondered if anyone had any experience of these bikes in terms of known issues, weaknesses or areas to check on the engine so I can make sure to go through these as I progress.
Cheers,
Andy

Bryanj:
Centrifugal oil filter on end of crank inside clutch cover needs cleaning and rarely gets done, cam chain tensioner system same as 400 four, lots of oil changes and insulating tape inside points cover to stop them shorting intermittently.
Dont thrash it from cold it will shatter rings and carb diaphragms, along with standard caliper/master crud problems

Anything else?

AshimotoK0:
Cam notorious for seizing in the head and trashing itself, the rockers, head and cover..... the cam bearings are just a machined into the alloy head  and cam covers ... oil starvation is usually  down to P.O. not changing the oil regularly and, as Bryan says, there is no easy access to the centrifugal oil filter on that model.... it requires removing the clutch cover. My first course action would be to take off the cylinder head cover and look for signs of oil starvation and take it from there.  Bottom ends are usually fine and the 5-speed gearbox is said to be an improvement on the 6-speed G5.

Forks and swinging arm are longer than the 400/4 and G5 which I think was done to improve the handling.

Original 2into1 exhaust systems are rocking horse poo and hence very expensive (often worth as much as a complete running bike). Wheels and disc brake are common to the 400/4 and G5 models. Rectifier terminals corrode and drop off.

AndyD:
Thanks guys,
Engine fully stripped this morning - had to wait for a castle nut tool to remove the centrifugal oil filter thingy.
So far looks promising but have now given everything an initial degrease / clean so I can have a close look at all the bits tomorrow.

You're both right about the oil filter - the centrifugal bit was pretty well solid gunk and the oil filter pretty messy, however there didn't seem to be any major damage evident from initial look (although may be different once I have a closer look at cleaned bits).

I've got two pretty well complete 250's, a spare 250 engine and a complete 360 so hoping to have enough good bits to get two full bikes up and running.
The 360 has a really good condition exhaust on it although the silencer is for the 250 - I'll probably use that on the 250 as a full restoration and the 360 as a decent runner with some universal silencer or other.

From the stripdown it seems the cam chain tensioner is different to the 400 with a simpler horseshoe mechanism - again all seemed in decent condition so far.

Cheers,
Andy

bobv7:
After all the flurry of triumph and success of the multi pot bikes Honda along with several other major Japanese bike manufacturers seemed to suffer from a collapse of imagination. From what I remember this bike appeared to be a genuine Honda stop gap "parts bin", very cheap, special with no great expectations of it having long and heathy service life. I personally know of 2 identical very low mileage machines expiring with major valve problems. At about the same time folks discovered that some of the new? CB500T had valve stems that would bend under the pressure of a hard stare. Honda had got a bit lost at that time but unlike the British bike industry recognised this and managed to find a way back.

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