BR250 spark issue?

[mendoAu]

After allot of reading about "bad carbs" and NGK vs. Champion plugs, coils and valve adjustments I'll call it right now..... if you follow the above links and replace that strange, mysterious black box called a CDI I'll go on a limb and say that it will fix most issues of off and on again sparkage (my term...HA!). It is little more than an enclosed capacitor and like anything hightech has the tendancy to work, semi-work and not work which leads to a troubleshooting nightmare. If you read the "myth" link it will become apparent that with a little wire de-coding and solder work I am pretty sure that a cheap ($10.00) cdi will probably work in dang near any engine. Some have more bells and whistles than others but like in my case with my 84 200es I had to cut the grey wire and just cap it off. Took bRed out today and that cheap cdi has got it running great. Starts in cold weather with no choke, idles great plug has that light grey, dry perfect color when checked. Once again thank you kbOnly for the info.

[Hair Bear Bunch]

Nothing much to report yet, except that the carb from the net has arrived and apart from having 10+ years of shelf dust and rotten fuel sludge in it, it appears to be in ok condition so a good and careful clean first then see what time I have this week.
The only observation so far is that the plastic ring arrangement that goes in the bottom of the float chamber around the main jet is missing.
Onward...

[Hair Bear Bunch]

A quick update...
Got the replacement carb fitted today, hasn't made any difference so it's on to the CDI next.
Some I've looked at have the same plugs but according to a check between the advert description and the manual the pin positions are different. One ad I read said the cdi fails because of a faulty regulator? Yes/no?

[mendoAu]

Re-read this thread and just checking...you have a 1985 250es...correct? And just my .02cents I think cdi's wear out 'cause they are thirty years old. I wish (after looking at allot of them) wiring diagrams would actually show the pin location/wires of the cdi box 'cause most just show them going to the box. Unless someone more knowledgable about reading diagrams could point out something like "starting from left to right wire #1 goes to upper left pin" or something.

[ps2fixer]

Re-read this thread and just checking...you have a 1985 250es...correct? And just my .02cents I think cdi's wear out 'cause they are thirty years old. I wish (after looking at allot of them) wiring diagrams would actually show the pin location/wires of the cdi box 'cause most just show them going to the box. Unless someone more knowledgable about reading diagrams could point out something like "starting from left to right wire #1 goes to upper left pin" or something.

Completely agree the wire diagrams shouldn't just show what connects to what, but which pin they go to. I'm hoping to re-create wire diagrams to assist me with making the harnesses, but the layout I'd be using is to mimic the actual wire harness shape more than readability for troubleshooting. Haven't made one yet so I can't really show what I'm talking about .

[Hair Bear Bunch]

Hi, It's an '86 with the HA08 4+2 pin cdi.
I'm using a Clymer manual which I think (not to hand so don't quote me!) gives the pin locations in one diagram and their place in the circuit in another.

[danbur55]

I have seen a pin out diagram I think on atv connections forum it seems they were all standardized as far as location of circuits will try to find it and post it

[ps2fixer]

A lot of things are standardized from honda to honda, except one thing I can think of, the round cdi plug I know for a fact gets wired differently on different machines. 85 250es is not the same as a 85 250r even though the plug is the same.

[mendoAu]

Also the round 1985 cdi plug is not wired the same as the 1984 200es round plug.

[Hair Bear Bunch]

Progress report...
Managed to get a few minutes with a spark tester today, and there doesn't seem to be any failing in the spark ie when it gets to the rev range where it hunts there is no loss of spark through the tester so I'm taking a reasonable guess that I can rule out the pickup, cdi and coil.
I'm now thinking if the cdi could be letting the timing slip at higher rpm?
I'm still not convinced it is a carb problem as I can change between two carbs I have and still have the same fault. Haven't yet had a chance to recheck the valves though.

[phantomtracer]

Maybe it's the volume of fuel being supplied to the carb


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