mint timing

[Ralph]

Hi Everyone, Just picked up a 70's mint 400. The stator was off and i can't figure out the correct position to get it resonably in time. Anyone? Thanks, Ralph

 

[Mike Lenz]

2.4-2.5mm btdc. I use a spark plug hole held dial indicator. You leave the stator loose and a pin goes through the flywheel into the stator to time it. Can use a 1/16 drill bit but is a bit loose.

 

[Ralph]

Hi Guys, What i'm trying to do is figure out exactly how the stator sits on the motor. There are three possible positions. I can't find a pic to give me a clue. With the "motoplat" at about 11 oclock i get a slight backfire out of the exhaust. I've tried all positions and can't get it to fire. Thanks for the help.

 

[rob w]

Ralph,
The wire that exits the stator has to be around the 10 O-clock position, of the three possible positions it could go, you can't mistake the right one, about 10 O-clock, and because the wire is headed up that way to exit the slot in the cases, and go to the coil.
The pin hole in the flywheel also comes out near the 10 O-clock area, but you'll need a indicator to fine tune it. Hope this helps.

 

[Ralph]

quote:
Ralph,
The wire that exits the stator has to be around the 10 O-clock position, of the three possible positions it could go, you can't mistake the right one, about 10 O-clock, and because the wire is headed up that way to exit the slot in the cases, and go to the coil.
The pin hole in the flywheel also comes out near the 10 O-clock area, but you'll need a indicator to fine tune it. Hope this helps.

 

Thanks Rob,
 Thats exactly what i'm looking for. I had it at that pos first and could not get the stator to adv and ret very much. Thats why i thought i had it positioned wrong. I'll put it back that way and start over. I don't have the indicators to do it correctly. I may have another problem altoghter , i do have spark, just doesn't seem reliable. I'm also going to go over all the grounds. Thanks, Ralph

 

[tomale]

Ralph,
I had asked Al B. about the same thing for my bike. I do not have a dial indicator. Al suggested taking a bolt with the same outside diameter as the inside diameter of the sparkplug hole. it should be just loose enough to move up and down when it rest against the piston. next you will need a small metric ruler. You should be able to find that any place school supplies. With the bolt in the sparkplug hole place the small ruler next to the bolt so that you can determine exactly where TDC is.moving the crank up and down while watching should help yOu do that... be careful not to allow the bolt to get caught up in the porting. Once it is at TDC move the crank counter clockwise 2.4 mm. At this point the hole in the stator and the hole in the flywheel should line up. I use a piece of wire from a metal coat hanger, it is just the right size.
hope this is of some help

Thom Green,I own and ride a 76 250 MC5 MX which I bought new.

[Ralph]

Thanks Thom. I'll give that a try. This bike ahs a loose big end bearing and i think i'm going to have trouble running it. I just wanted to she if she would run before i decide  what i'm going to do with the bike. Are rod kits available for theses bikes? Thanks for all the replys!

 

[tomale]

I believe that they are.  I have not needed to rebuild my 250 yet but I think that that you should be able to get almost anything that you might need. you might need to do some looking but if nothing else you can get in contact with DR. twostroke. He seems to have all the stuff that no one else does. only problem is that he is in sweden I think.

Thom Green,I own and ride a 76 250 MC5 MX which I bought new.

[john durrill]

Harbor Freight, Enco and a lot of other discount tool outfits sell dial indicators.
 You might have to make up the holder that fits in the spark plug hole. Most big bike parts suppliers sell them in the tool section of their catalog and they come with the holder.
 Euro Rod makes 250 rod kits and Al carries them. Euro Rod just moved to Florida so if Al is out it might be a while before he gets a shipment for them. They (Euro Rod) only sell rods through shops or vendors like Al.
 Dr 2Stroke will probably have rod kits also.
 He is in Switzerland I think.
 John D.


 

[Kip Kern]

I would contact Al Buehner or Larry Perkins to see if either has a Sachs timing tool.  This device will work on any engine to give TDC and meet any timing requirement.  All you do is screw it in the sparkplug hole finger tite and rotate the engine.  About a 15 minute job!