Yamaha dt250 1972
Posted 11 March 2012 - 04:39 AM
Posted 11 March 2012 - 07:07 AM
Back the the upper coil - the resistance through the two small wires will be very small - so make sure the ohmmeter is set properly (esp if analog). In the short time I have right now I'll just say to search for primary & secondary ohmmeter reading and I'll bet my donut & coffee that you need to look under the flywheel.
Posted 11 March 2012 - 01:39 PM
Posted 11 March 2012 - 03:47 PM
CHECK THE MUDA&%$#@!EN TIMING AND POINTS!!!
Don't mean to be rude, but I'm STILL frustrated over what happened to me with my stupid KE from 83......... Ran fine for the last guy, got it home, replaced plugs, ran for 10 minutes, dead, replace plugs, ran for 10 minutes, dead. etc. etc. etc......
Open the left magneto cover, adjust that stuff inside there. then make sure all connections are 100%, clean carb, check compression, air intake, and possibly leakdown. If you do that, it WILL work.
Posted 11 March 2012 - 07:44 PM
Posted 11 March 2012 - 08:05 PM
Posted 12 March 2012 - 02:12 AM
I think a leak down is a compression test that tests the entire block? idk I never got that far but they say it's favored over a comp. test in 2 strokes. I'm pretty sure 2Ts (2-strokes) don't have cams but someone please correct me if I'm wrong. As for the exact procedure of setting the points I'd (and you're gonna hear this a lot) refer to the manual and do it off that. Do you have one? I can look around for a free one if you want, no guarantee there will be one though!
Yeah I got a lot of backfires when trying to force start it. One way to really get it going is to bump start it. This is where you put the bike in N, run down the street next to it, then as you jump on, kick it into 1st (down) and gas it, then as it starts pull in the clutch and keep it from dying by keeping the revs up (remember things like choke, gas on, key, etc. before you start). When you kick it into 1st you'll either hear a "WAAAAaaaaaannnnnnnnnggggg" (not wang, sound it out) then stop, that means something's wrong. If you hear a "BADINGADINGADINGDINGDING" that means it's working.
Also, it isn't recommended you use actual starting fluid (ether) to start a 2-stroke. A 2-stroke is premixed or "oil injected" to where if you're not getting gas you're not getting oil. Which means by spraying a very "dry" flammable fluid in it it will just hurt it more if it starts. Ether is an exclusive product for 4-strokes. What we use is WD-40, works better when it's straight in the cyl, not a sure thing that it will work, but yes I would suggest using it for the first or second bump start.
Ahh yes I almost forgot.... Before I adjusted the points to where it worked 100%, I had actually sprayed WD-40 into the rusty points. Yes, open the cover, see the spinny stator bowl with the coils inside, there'll be some markings talking about TDC, take the WD, and flood that little be-otch with it! Okay not that much, but get a good amount all around in there, but put priority on the points (not the copper coils). This is something easy to do before you get the manual.
Also, what condition are the plugs? Are they all oily? Carbony? You'll want to have a new plug for after you do all this, but not immediately after, after spraying it kick it a few times then replace the plugs and bump start it with the wd-40 in the cyl.
So to recap!
-Buy a new plug
-Spray a decent amount of WD-40 in the stator area with priority on the points
-Close the lid to it
-With the bike turned off, give it a 5 or so mild kicks to get things moving, but don't start it!
-Remove old plug, spray a quick burst of WD into the cyl., replace with new plug
-Walk out to street or a descent, make sure it's fully on (gas in tank, keys on, fuel on, killswitch off, choke on)
-Perform bump start, be ready for it to act weird. In other words, don't freak out if it bursts to life. Because if it comes to life, it's coming to life.
That should be all, but it's 4:00am and I have one heckuva headache so if you think you're missing something or need to do something you probably do.
Please ask any questions you have, and I'll do my best to help, 'cause I know this is confusing.
Edited by twistedkeys, 12 March 2012 - 02:12 AM.
Posted 12 March 2012 - 02:14 AM
Posted 12 March 2012 - 02:58 PM
Posted 12 March 2012 - 05:11 PM
You will be able to easily get used and new parts for this bike. Ebay and thumper talk parts store.
Edited by yellowsnow, 12 March 2012 - 05:14 PM.
Posted 12 March 2012 - 09:24 PM
Posted 12 March 2012 - 10:52 PM
Posted 13 March 2012 - 03:11 AM
Yeah I did forget to mention.....before I did anything I listed above, I replaced the entire top end... It wouldn't hurt to do it, most guys won't buy a 2T without immediately redoing the top end.
Posted 14 March 2012 - 07:07 AM
Posted 14 March 2012 - 07:09 AM
Posted 14 March 2012 - 07:16 AM
Posted 14 March 2012 - 07:35 AM
It will probably be pretty nasty. If you're going to clean it (which you don't HAVE to, it's not a big deal), do it very lightly, take your time, carbon is very very hard to remove, it doesn't have to look brand spankin' new. The only problem I see with doing it is that you don't want any of that crud in your cyl or bottom end, and I mean any of it, keep it contained. That, and because you're increasing the volume of that area, it might have less compression? idk that's over my head... But again, just make sure none of the carbon gets into the cylinder.
Posted 14 March 2012 - 07:48 AM
Posted 14 March 2012 - 08:07 AM
No problem dude, I didn't learn all that for nothing!