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Layspowersports
08-04-2012, 10:53 PM
Hello folks, I have a question about a 1985 250R ignition system. I traded a fellow a few months ago one of my 350X for a pretty nice 250R. My 350X needed a cam and his bike never ran after he replaced the intire ignition system. When I say ignition system I mean he had replaced the stator, coil, and CDI with “new“ pieces that are not Honda. He was like me and had several 250Rs and thinks he put the 85 flywheel back on it. I have two completely to the frame right now and could see mixing parts.
Now flash forward 5 months (or more?). I decide to get the bike out and test it all. First test and she has excellent compression (over 200 lbs). Second, I removed all the new parts he placed on it and put a true 85 250R Honda CDI, new NGK plug, and a NOS coil on the bike. She has super hot fire for sure now.
I then placed some good fresh fuel in it and kicked her over twice and she felt like she wanted to fire up (hits for like second then died out)… but she will not crank and run to save it’s life and it kicks back sometimes like a 12:1 350X does. I had already cleaned the carb even though it was in great shape. I have heard that some 250Rs have been built with such high compression they will not crank without a tow (same guy I got this bike from told me this).
In comes the Big Red and around the yard I go being pulled and laughed at by my wife (she loves me?)… Nothing… I decided to take all the hot rod 39 mm “racing carb” and rad valve off. I then replaced them with a stock carb and reeds off my 86 rider. Still no cranky but fires and has great compression. Is it the flywheel? If he put an 86 on it would the trigger be off? What do you guys think? I have wasted 4 hours and a pair of shoes on it…
I am an ICAR and ASE mechanic/body man with over 25 years working on cars and bikes (and riding three wheelers for 30). I would like to say I am about to just swap over a complete ignition system from a running bike if I cannot figure this out but it is driving me crazy! It has to be something simple, right? Is it even possible for the ignition to be out of time?
Thanks for any and all help!

Layspowersports
08-04-2012, 10:58 PM
I even tried a little starting fluid and she did not crank...

3wheelrider
08-04-2012, 11:07 PM
Check the marks at on the flywheel at TDC (make sure it lines up) & or remove flywheel & make sure the woodruff key is not removed or sheared. 86 flywheel is fine. -I say swap another stator in after that. Does it have a timing advancer kit?

Layspowersports
08-04-2012, 11:16 PM
I will take the cover off after church tomorrow and check. All I know is everything he put on that I took off says made in China all over it so far.

yaegerb
08-04-2012, 11:17 PM
You say you have another 85 flywheel? I would put that on and see if it makes a difference...

Also, is the plug wet? Are you getting fuel to the spark plug?

I would also pull the air filter and try to start it with the air filter off.

atc007
08-05-2012, 07:49 AM
Lol,,,we're all different! To me crank,,is turning over,not running,,fire to me means running. Anyhoo,,200lbs?? Someones been goofing around inside! I know that is healthy,,but I shyed away from anything over 200lbs back in the day for fear of blowing crank seals. I know they will hold up to 220 or so.. But Quad Racers didn't like it ;). I would be thinking flywheel key and cdi in that order. Obviously,cdi being the easiest to swap out. you say he had replaced" everything" with NON Honda parts?? You lost me there. But you say you have a nice hot blue flame,,maybe it's not ignition,,but I think it must be in the timing of your spark hitting.

bannedbrraap
08-05-2012, 12:22 PM
Stock 85 stator wiring is reverse from 86....all aftermarket stators come wired 86 style....if it still has the 85 style harness and cdi box, reverse the 2 stator wires in the little white plug...

deathman53
08-05-2012, 08:16 PM
it shouldn't be any issue with the stator. I have put a 85, 86 and 88 stator in a 85 ignition system, all ran fine. The only difference between 85-88 and 89 stator is one connector. Also 85-89 flywheel are all compatible, The difference is the weight of them. I am gonna say that the issue may be the flywheel key,I had that issue on 2 of my bikes.

ceaserthethird
08-06-2012, 06:40 AM
I'm with Deathman53 on this, Flywheel key aka woodruff key.

MTS
08-06-2012, 10:37 PM
i would say your ign time is too far advanced one way or another, or someone re rivited the mag magnets on wrong. could be who evere messed with it last advanced it the search for power, that is high compression numbers..possible the stock adv is too much.

Layspowersports
08-16-2012, 11:12 PM
Well, first of all I want to thank you for the tips and suggestions. I really did not have time to look at the “R” until yesterday. My family all had the stomach bug (the whole family was down for days) and then a non stop work week took all the wind out of my toy time.
When I took the flywheel cover off I found two things: an adjustable ignition and a shirred flywheel key/pin. I left the ignition timing alone and replaced the key and she fired up on the fourth kick. I was told by this guy all he did to it before the trade and I have to say it will haul tail and looks good for a 1985. Thanks to all again for the help.

3wheelrider
08-17-2012, 12:34 AM
check the marks at on the flywheel at tdc (make sure it lines up) & or remove flywheel & make sure the woodruff key is not removed or sheared. 86 flywheel is fine. -i say swap another stator in after that. Does it have a timing advancer kit?
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