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Rusty-150
10-11-2012, 10:41 PM
Hey just want to say hi im new to the forum and im lookin for some help. So i recently bought an 85 250sx in rough shape. Ill see if i can get some pics up at somepoint. Well anyways the seller said the engine in this trike is siezed . Apparently he took for a ten km run and shut it down hot went out later to kick start it and it was hard as a rock. Well i got it home and after rockin it back and forth a bit in gear the kick start will work for a kick or two then jam up a bit. And when it does kick over its not turning the top end just spinning a few shafts, oh and the starter gear and the gear the starter mesh with are both chewed right up teeth missin reall nasty lookin. So i popped the side cases off and started too look at things the kick start gears are all intacked and once i took the left side cover off the kick start wont jam up anymore but still wont turn the top end over then i rememberd the shifter seemd to stick up or down so i rotated the shift shaft a little and all of a sudden the top end kicks over and dosent feel to me to be siezed , so im gona try to get it back together tonite and see what happens . I dunno yet what was causing the kick start to jam the stator looks really chewed up full of metel gear chunks . So i duno if i should try to fix this engine or there is s 250 es motor for sale not far away what do u guys think? Any ideas whats goin on with the kick start?
Thanks

Rusty-150
10-11-2012, 10:50 PM
Well i got it put back together tonite minus the stator i think it was jamming up ,checked the timming and put fresh oil in it. Put a little gas in it kicked it over and it fired up for a second so im thinking it isnt siezed. Tried to kick it over again and now the kick start isnt engaging so i dunno maybe wasent back together right. So anyways as i was dumping out the old oil. I found a locator bolt in the oil. Ill try to get a pic up as soon as i figure how. Looks like a stud with a jam nut on it. And the end of the stud is machined smooth im thinking there must me some fingers that run on it i dunno where it came from or what its for im thinking i should pick up that engine for sale haha

tri again
10-11-2012, 11:30 PM
so? imagining a regular 8 x 1.25 mm bolt about 3/4 inch long and
then someone machined a non threaded stud shaft on the end of the bolt head.

Common locator pin that holds the shift shaft spring. is what it sounds like.

I'll post pix and part numbers tomorrow.
Gotta run to work.

you'll get it.
we always do.
Congrats, btw

Rusty-150
10-11-2012, 11:49 PM
Sounds like it155667

tri again
10-12-2012, 03:24 AM
Sounds like it155667

yupp!
they're like 9 bucks and available almost everywhere.

If you take the left side cover off, it will be right under the shifter.
I prob have pix in my account here.
EZ fix and a great way to get a good deal on a misbehaving machine.

Lay the trike nice and flat level as possible.
New cover gasket and way under an hour to do.
No real surprises unless you drop something down inside the engine.

see if you can click on the following:
service manual

Plus the search key has been working like a dream. There are quite a few good posts on this topic.
bikebandit.com has the exploded parts diagrams with part numbers.

Sure be nice to find the other piece, eh?
I've been putting neodymium magnets on all my drainplugs.
Just snap them to the outside head of the plug to attract metal filings.

It'd sure be nice to clean that engine out somehow.

JasonB
10-12-2012, 02:39 PM
shocked there hasnt been a few people to point you towards shop manuals on line for these bikes! and if you want to clean you motor out you could spray some stuff in there like pb blaster or simply spray some gas in there using a little sprayer. meh. You can use almost anything besides water to clean it out. Search lol. I used PB blaster and then a few changes of gas to flush the diff out on my GF's 87 250sx. just an example. We have used eith ATF or power steering fluid and runing the motor for a short period after sinking my brothers warrior. That was more to remove water than to clean it though.


Sounds like your off to a proactive start! keep it up! Search feature is your friend though

tri again
10-12-2012, 03:15 PM
Can't imagine you'd ever be tempted but never,
don't even THINK about removing the big allen bolts holding the right angle drive
output from the side of the engine unless you talk to dirtcrasher.

Everything else is fixable by mere mortals.

Did you happen to see all the posts about 'shift'
or "shift problems"
or shift linkage?

Credit to flying w for the pointing finger picture btw.

Rusty-150
10-12-2012, 03:32 PM
Oh yaaa i know the shop manual is a big help dad has one for the 250 es im hoping it will cover the 250 sx aswell. And ya im gona flush the engine out somehow dunno how yet. And whats this thing i should never take apart?

tri again
10-13-2012, 12:13 AM
Oh yaaa i know the shop manual is a big help dad has one for the 250 es im hoping it will cover the 250 sx aswell. And ya im gona flush the engine out somehow dunno how yet. And whats this thing i should never take apart?

Where the driveshaft connects to the engine?
Some pencil sized allen bolts hold the right angle drive to the engine.
Swing arm bearings, u joints, driveshaft boot etc can be worked without ever touching those.

I just bought one they had taken that thing loose and the whole thing's going in the 'parts' area.
Nothing to worry about and nothing ever goes wrong in there it's just that it's tempting to remove for various repairs but is never necessary.
There's a thrust washer deep inside the cases that falls down inside somewhere and
also has some oil metering hole..easier to get another engine.

tri again
10-13-2012, 12:17 AM
Oh yaaa i know the shop manual is a big help dad has one for the 250 es im hoping it will cover the 250 sx aswell. And ya im gona flush the engine out somehow dunno how yet. And whats this thing i should never take apart?

The manual should cover both sx and es.
Did you find the other half of that shift pin?

Rusty-150
10-13-2012, 09:30 AM
Ya i was looking last night and figured that must have been what you guys were talking about. And yes i found the ither half its still threaded into the case broke off flush so i brought home my easy outs gona try and get at it this weekend . But anyways that darn kick shaft assembly fell out or came out of the case tbe other night asci was kicken it over and im havin a heck of a time gettin it back in . I red some posts on it and looked on the online manual, so i guess you have to put it in on an angle and hook the spring on the outer hole in the case then pull the shaft out a liite so it dosent mesh then rotate it clockwise till the nub is about 11 oclock and insert it into the case and rotate conter click wise to lock it in. Sound right? Any other tips?

Oh ya im havin trouble finding that pin thats broke live to find a place in canada that has them guess ill try a honda dealer, And one more thing so far i need a stator that pin starter gear and starter mesh gear . There is a 85 250 big red motor for sale two hours away hes also thriwing a bug red rear axle in All fir. 200 do you guys think thats worth picking up ?

Thanks for all the help guys