CR250 problem

[jonevans]

Lately I have had a load of trouble with my bike. Over a month ago, i started having trouble with it "bogging" and cutting out. I then took carb off etc and noticed by carb-boot had a tear so thought this was the problem. I replaced this and it seemed to run fine. The last week the bike just died out on me and i couldnt start it. I put a new plug in it and away it went.
But then this week the bike started dieing out on me again. I would be goin along and when the hit of powerband quicked in the bike would miss really badly and sometimes backfire. The problem only happens when the you are wto.When you are in low to mid revs the bike is fine.
Now today i started the bike to show what was happening to everyone and it went fine no missing or backfiring - ran perfect. So it looks like the problem only happens when the bike is hot but most people seem to think its an electrical problem.
Im just not sure what the problem is and where to start. Im very tempted to take it into the garage but unless the bike is riden hard for half to three quarters of an hour they wont be able to see what is happening.
Just wondering if anyone has an ideas of what it could be.
Oh yeh the bike is a CR 250.

Cheers
Jon

[crdemon]

it does sound like an elecrical problem. whats ur plug look like? sounds like u can ride long enough for it to start to foul.

[PBMAXX]

If it's heat related, and if it is electrical, then it is probably the coil. I don't know how expensive spares are in the UK but a spare coil is always a good idea. With an extra one you can at least rule it out as the culprit....

[ossagp]

stators exhibit the some of the same symptoms that coils do. that is that they breakdown when hot. i have yet to have a honda cr coil go bad, but several honda stators have,,,beginning to miss etc when hot and finally quit running altogether.

another possibility is that your is running overly rich. don't try any jetting changes until you go to Faded's post on setting the float. im am guessing that yours probably hasn't had that treatment since you had it. do that first, then see if you can get your coil and stator tested if that does not cure the problem. remember that a worn cylinder and compression loss can make a bike act rich too. (if you are unfamiliar, rich in this case means more fuel getting into the fuel air mix than is required for proper performance.)

[jonevans]

I dont think that the bike is running rich, i have never had any trouble with this before and havent touched jetting etc as i have seen no reason to. The bike hasnt lost any compression well not any noticable amount anyway.
I still havent looked at the bike, ive had no time but will have a good look tomorrow. I have been told you can test the coil for resistance to see if it is all ok, so will look into that.
I will have a good look at the bike and see what i can find. I havent even checked all the wires to make sure none are shorting etc, so could just be as simple as that. I will drop a note as soon as i find out.

cheers
Jon

[YZER-409]

We had the same problem on an 84 cr125 the stater of the magneto went bad, you should check the resistance of the stator. In the United States a new one cost around $200. We sold the bike before we bought a new one because it wasnt worth the money to buy a new stator. Also check the float valve in the carb. This will also cause the bike to bog down after a short period of time. Check the gas flow out of your gas tank petcock. Check the gas line from petcock to the carb.

[TheReverend]

replace your spark plug cap and wire. My cr has done this same thing and was due to a weak spark. try the $8 fix first..

[redmistcr5]

where you from in wales mate,im from bridgend area,im sure iev got some electrical bits here for a 90 cr250,i went through the same trouble as you with my 90 cr250,drove me up the wall,the jetting was spot on new stator,new coil ,plug lead and so on,must have gone through 50 plugs,tryed cooler plugs,hotter plugs reset power valve to no avail,sold it in the end and bought a 500 with no trouble,i wouldnt have that 250 back if it was free,i wonder if you bought it

[522]

You should try changing the ignition wire, or the ignition coil. Theres a brand called nolgy, that put an ignition coil to boost the spark 100 times greater. [Only registered and activated users can see links. ]

[522]

I meant [Only registered and activated users can see links. ]