88 Cr 250 Cdi

fadingfastsd

Member
Sep 7, 2005
20
0
Hey guys I had a previous post about my 88 CR 250 not starting. I traced the weak and non-consistent spark problem to a bad coil. Thats been replaced and spark looks good but the bike still will not start. He tested the flywheel, pulse generator, and stator, and all are good. He believes the problem is the CDI box, which is allowing the plug to spark, but still not right for some reason. I need to know where I can find one of these, there isnt any on *the auction site* but I need one asap. I'm all out of ideas. I had the carb professionally rebuilt and jet settings checked, compression is great (around 130), I repacked the muffler. I dont know what else it could be. WHen kicked the bike will backfire but never start. Any ideas where I can find a good used CDI for an 88 cr250!!???
Thanks, Evan
 

mobrown

Member
Jan 26, 2004
198
0
Backfiring?

Is it possible to put something in 180 deg. out of whacK? It sounds like a timing type of issue if it's just backfiring. I have a 91 CR250 and have not had any electrical problems so I can't speak from experience.

Also 130 psi? Seem like it should be around 180 to me.

My $.02
 

MikeT

~SPONSOR~
Jan 17, 2001
4,095
11
If it's backfiring then you have a good spark. How have you verified the timing is correctly set?
 
Sep 1, 2005
25
0
my buddy has an 85 cr250 and it sounds like you have the same problem he bought a brand new cdi box from motosport and it fired up 2nd kick hope this helps
 

fadingfastsd

Member
Sep 7, 2005
20
0
what is 'motosport', do they have a website? They still make brand new CDI's for that old of bikes? I found one e*b*a*y but i'm not positive it will fit my 88. How do I tell?
 

viking20

Sponsoring Member
Aug 11, 2002
428
0
If the bike still backfires and refuses to start or runs poorly, check the crank seal under the flywheel .
 

sunnyboy

Member
Feb 24, 2003
98
0
sounds to me like you have loaded the bottom end up, this was done while you were having coil problems and you have fixed that!!! put a good plug in it and tow it to get a good bump start with the choke off,throttle wide open. it may take some time to blow it out and for it to start.after it starts ride it for a while.you will need to repack your silencerwhen all is done as it will get soaked
 

fadingfastsd

Member
Sep 7, 2005
20
0
I was acutally thinking about this before, and it could be flooded really bad with alot of gas down in the crank from all the kicking w/ no spark. How do I blow it out? Will towing it with the choke off and throttle open help to clear it? Should I do that for awhile, then try to bump start it from being towed? Can you give me some more info on this, and i'll definitely give it a shot before buying that CDI. thanks!!
 

fadingfastsd

Member
Sep 7, 2005
20
0
ok ive got some updates on the bike. i took it to my neighbor who is a retired professional motorcycle mechanic. I replaced the coil with a stock coil off an 89 CR250, and am getting a strong consistent spark. We took off the flywheel, the woodruff key is in perfect shape. The stator measures perfectly within specs. The kill switch is fine. He though the bike may be flooded from all the previous starting attempts with no spark. I towed the bike behind my bros truck w/ the plug out, hoping to clear out any accumulated gas. We then repalced theh plug, and towing the bike, tried to bump start it. Again, I get a backfire, but no sputtering, no starting. The mechanic belives the problem lies with the CDI, which is affecting the timing. There is timing marks on the stator and the engine case, which are lined up perfectly. The timing procedure in my shop manual requires the engine to be running to check it w/ a timing light, so I can't check that to be sure. Could this problem lie in the CDI? Does anyone know if an 89 CDI will fit the 88 bike? I know mine has 2 molded 2 wire connectors, and the 89 has 1 molded 2 wire connectors and 2 individual (not molded into 1 plug) connector, but I'm assuming they're the same function. The bike is currently for sale now, as even when I get it running I'm selling it to buy a new bike to cut way down on maintenance. Thanks again guys
 

jake_0209

Member
Jun 17, 2006
2
0
CANT GET THE BIKE START! yet......?

hi, dude i got the same problem when i bought my 86cr250, i read all your problem about your bike... got same problem.. i'd found the problem for almost 11yrs never work in the garage im still never fadeeeeeee... your problem is " change left crank seal flywel side.., if still not working change the right crank seal., cluth side...,, im pretty sure you got your problem solve....
 
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