250sx motor help!!!

[Honda_man250sx]

Well me and my friend were riding my 1985 250sx it all of a sudden made this grinding sound in the bottom end so I pulled the motor out of the frame and took off the right side caseing because the noise was on the right side and i found quite abit of metal filings (copper color) inside and i just changed the oil like a week ago and i only drove it a little bit since then and not hard either. it looks like there more fillings inside the tranny but i havent split the engine yet. any ideas what it could be?

[Tri-ZNate]

when I had grinding noise my kickstarter gear fell out of place and locked the whole engine up. But I cant think what would be copper color in there.

[Hornetpowerspor]

I can't put my finger on the copper color yet. If I remember correctly the 85 SX's and big reds had a factory recall. It seems like they put a new cdi box in them with a lower rev limiter. The reason for this was that they were common for breaking crankshafts due to high RPM's.

On another note, maybe you seized your rod bearing, and you are seeing shavings of your gold colored connecting rod. Hope that helps ya. Keep us posted!

[Howdy]

I'm willing to bet your noise was caused by the one-way clutch going bad. Does the kickstarter work correctly? Or does it slip when you kick it over?


The copper colored shavings is probably from the bearing in the clutch housing wearing. Just my 2 cents.

Howdy

[Honda_man250sx]

if the rod bearing siezed and its the rod thats worn would the enginge still run tho because it still does and the crank looks fine on the right side and its the right side thats sapossed to brack during over rev.

[Howdy]

If the rod bearing seized you would have silver colored shavings not the copper colored ones. The only copper colored ones I can think of off the top of my head is the clutch housing. But I could be wrong.

Howdy

[Honda_man250sx]

sometimes when * kick it over the kick start slips and grinds then springs back real quick if its the clutch what would i need to fix?

[Honda_man250sx]

with the side casing off the clutch looks fine it dont wiggle or nothing

[Howdy]

sometimes when * kick it over the kick start slips and grinds then springs back real quick if its the clutch what would i need to fix?
When you shut the motor off did you hear a whirling sound, and possibly followed by a clunck?

Here is another thread on the one-way clutch topic:
http://www.3wheelerworldforums.com/showthread.php?t=10576


with the side casing off the clutch looks fine it dont wiggle or nothing

Does the centrifical clutch spin freely? Or does it engage one way but not the other?
Howdy

[Honda_man250sx]

when * shut it off * can hear a wierling sound itll stop
when * try to kick it over when * still hear the wirling sound the kick start fetchs up and stops it

[Howdy]

Your one-way clutch has gone bad. It's time to replace it. See the link I posted above.
Howdy

[bigredhead]

got a digital camera ? pictures would be good right about now !!

[Honda_man250sx]

i brang my engine to my friends uncle who works on bikes and he thinks its the crank

[Honda_man250sx]

but the clutch must be bad tho because sometimes when * gear down it dont slow down till * give it a lil gas

[Howdy]

If the crank is bad you would have more problems than you do. As far as the one-way clutch: The one-way clutch is designed to engage in one direction but not the other. This set up is needed so that you can use the kickstarter, and or be able to pull start the machine. It also works to stop the motor from spinning backwards when shut off. Why stop the motor from turning backwards? Because of the way the electric starter and the drive ( gears and such ) are designed they can engage when the motor turns backward. If the motor turns backwards and the starter gets engaged you will destroy the starter and at least one of the gears. Thus for just this reason it is very critical to fix the one-way clutch.

The tell tail signs of a one way clutch going bad is:
#1 a whirling sound coming from the right side of the motor when it's turned off. Sometimes this is follow with a clunck sound.
#2 The kickstarter slipping when you try to kickstart it.
#3 The motor fails to turn over or when trying to pull start it with another machine.
Going with the information you have provided thus far: I can safely tell you your one-way clutch is wore out.

A couple ways to tell if your crank is bad or going bad:
Your motor would possibly have a knock ( at the front bottom of the motor ) when running ( this could be the rod bearings going bad ). But if it runs good ( no knocks ) while it's running then this isn't a problem. If you do have a knock you better fix this before it goes KABOOM! A KABOOM = You need to find a different motor.
On a rare occasion (sp? ) a motor like this may break a crank. If this happens YOU WILL KNOW you have a serious problem. I have yet to see a motor like this where the crank broke and you could still ride it. If the crank breaks the centrifical clutch will not turn, without it your not going any where. Also when the crank breaks you will know it because the right cover ( clutch cover ) will be broken. What happens is when the crank breaks it tries to push the centrifical clutch thought the case. And trust me it WILL at least put a crack in the case to where oil comes out. At this point YOU WILL have a mess.

Bottom line is this: If your friends Uncle thinks the crank is bad he must not know much about these motors. So you better not let him touch it. You would be better off trying to fix this problem yourself. We have quite a few users here on the forum that can and will help you with any questions you might have. Heck, there might be a user that lives close enough to you to be able to help with some hands on experance. ;)


If you can trust me and take my advice here ( replace the one-way clutch ) you will find that this is a fairly easy repair ( probably a 4.5 on a 1-10 scale ).

Also, you haven't mentioned it yet, so I will advise to get a good repair manual ( either a OEM or a Clymers ). With a manual you can save enough with a single repair to cover the cost of the manual ( over taking it to a dealer ).

Thanks
Howdy

[Honda_man250sx]

i have the clymers manual and i borrowed the oem one from a friend

[Honda_man250sx]

my mechanic found the problem it was the rod bearing

[Honda_man250sx]

i am having trouble to find a place to get the rod bearing put in now no one will do it

[Honda_man250sx]

Now i need to get a crankshaft with rod bearing and rod together in really good shape anyone have one for sale?

[bigredhead]

Before you go spending too much money on those parts.. make SURE the rest of the motor was not affected by the metal shavings.. the head.. valves. cam. tranny .etc etc etc..... in the long run.. it might be cheaper to find a new motor , complete. and use the one you have now as a spare.

but that all depends on the condition of the rest .

[Honda_man250sx]

well every thing looks good but if i could get a good new motor i would probly buy it too but i donno were to get parts like the crank at and a motor might cost alot to ship tho

[bigredhead]

You will find parted motors on e-bay frequently enough if you keep looking. if you only need the crank portion...

But alot of times.. it's motors that have blown up for various reasons and most of the parts are worn beond being good usable parts... always the exeptions tho... just be aware of the e-bay mania and junk.

[Honda_man250sx]

do * know of anywheres that they put in rod bearings because no one here will even the honda shop wont do it cuz you needa split the crank

[bigredhead]

Split the cases yourself and take the crank and connecting rod in by itself.. have them press a new one in....

A few places here in moncton would do it i'm sure.. ( have not actually called and checked.. but i'm sure Adriends or Milligans would do it. ) even try calling " Alan's cycle " alan's might have actual whole motors.

[Honda_man250sx]

well i already have the crank out and thats what they wont do is press in the new one
can * give me a number or call and check for me if they would do it?

[bigredhead]

www.Milliganscycleworks.com

ph: 506 855 4555 These guys are good to deal with. they do alot of vintage stuff.

[Honda_man250sx]

thanks man ** really helpful when i get er going again ill have to come for a biking trip with ya lol

[jeswinehart]

Hondaman ,,, I have a bottom end 85sx I would be delighted for you to have. But the bad news is I caculated the shipping at 45.30 parcel ( up to 6 weeks delivery ) or 4 - 10 days priority for 78.35 american money.
This motor had a issue of a silly ass owner messing with the cluth assembly and failed to put them in right . Clutch come undone and blew out the right side case. Top end was great shape ( and sold well too ) and the crank/tranny appears to be in good shape as well. The rod is tight up and down on the crank.
I sure would like to get it off my work bench where it has been sitting for over a year now.
I have something else but will pm you with that info so as not to violate forum rules.
It weighs 56lbs. and would top out at 60 packaged by my reckoning.
It would be coming from zip 49099 via usps. If you have a better way to ship just let me know.

john

[Rex Karz]

There is also a common problem with the shift ratchet assembly, search both sites and You will find it. It should be checked out and taken care of before You put th case back on.

[jeswinehart]

That is why the shift shaft is out the one I have ,,, it will be going in my 2nd. bigred that has a bent shift shaft. I have alredy robbed the ratchet paw thing off of it to fix another machine.

john