Posts
19
Joined
4/26/2011
Location
Mcadoo, PA, USA
Edited Date/Time
1/27/2012 12:59am
Ok guys i am new here, and some what new to MX bikes
I picked up a 2000 yz 250(2 stroke ) last year(guy owed me money so gave me the bike)
I had excellent compression, had a silid pull, all things on the outside seemed right, no leaks, and seemed to run just fine.
I ran it about 25 times on old logging roads, and some coal banks hill climbs.
and again ran soild, no issues at all.
NOTE: I changed the trans fluids, new plug, and air filters,and new coolant,
when I got the bike, also replaced the brakes,
I also picked up a service a manual to have,
just to be sure all was well with that stuff.
I again changed the oil at the end of last season
well I took the bike out for the first time since last year,
dumped the fuel, and started off with new gas,
it started on the second kick, smokes a TAD for a few seconds, and then idled and seemed to run fine.
took it for a run, and about 10 min in I stopped, and then noticed that I had cooolant coming out of the over fill line
it would come out as i rev the bike.
I shut it down
let it cool, checked fluid level, and it was low( checked it before going out and was fine)
re filled, started it up, as soon as it starts to get hot, it comes out the overfill tube,
the plug looks fine, changed oil again, to see if i had anything leaking into it, and as far as I can tell it clean , just oil!
any ideas on what going wrong/on!
I picked up a 2000 yz 250(2 stroke ) last year(guy owed me money so gave me the bike)
I had excellent compression, had a silid pull, all things on the outside seemed right, no leaks, and seemed to run just fine.
I ran it about 25 times on old logging roads, and some coal banks hill climbs.
and again ran soild, no issues at all.
NOTE: I changed the trans fluids, new plug, and air filters,and new coolant,
when I got the bike, also replaced the brakes,
I also picked up a service a manual to have,
just to be sure all was well with that stuff.
I again changed the oil at the end of last season
well I took the bike out for the first time since last year,
dumped the fuel, and started off with new gas,
it started on the second kick, smokes a TAD for a few seconds, and then idled and seemed to run fine.
took it for a run, and about 10 min in I stopped, and then noticed that I had cooolant coming out of the over fill line
it would come out as i rev the bike.
I shut it down
let it cool, checked fluid level, and it was low( checked it before going out and was fine)
re filled, started it up, as soon as it starts to get hot, it comes out the overfill tube,
the plug looks fine, changed oil again, to see if i had anything leaking into it, and as far as I can tell it clean , just oil!
any ideas on what going wrong/on!
Have also seen a broken cylinder base stud cause the same problem.
The Shop
DeCal Works Huge Plastic Inventory of UFO and Polisport kits.
Luxon 4-Post Bar Mounts
$189.95 - $239.95
I forgot to say, that before I put the bike away for the winter
I had a new chain and both sprockets put on at a local shop(due to me not being able to remove the front sprocket bolt)
I didn't give this a though as its a simple thing
BUT! today while i had it up on a high stand
I could see an issue
the front sprocket bolt, not sure what or why, maybe the new sprocket is thicker than the old one
but when they put my caser back on it was tightened up against the sprocket bolt
so tight that, I am amazed that the bike even rolled!
the bolt cut into the case saver, and shaved about a solid 1/8 inch into it
this had to be adding a lot of resistance to the engine
any way I removed the case saver
changed the coolant, to see if anything odd came out, and replaced with new coolant
I ran the bike on the stand, running through 1 st 3 grear, to get the bike good and hot
and it ran without any overflow issue's
so now question
could that bolt rubbing have caused the overheating, and thus the coolant to come out the overflow?
I plan to replace the o rings on the head, just in case, cannot hurt
but??
and has anyone ever heard of a sprocket being 1/8'' or more thicker than others for the same bike??
thanks again
http://www.lemonds.com/fiche_section_detail.asp?section=36470&category=…
I think when he said bolt he meant nut to hold front sprocket
http://www.lemonds.com/fiche_section_detail.asp
And some bikes do use a BOLT to hold the front sprocket, this is a 02 honda 450 for example
http://www.lemonds.com/fiche_section_detail.asp?section=141681&category…
I have no loose nots /bolts
it was whne the case saver(mine is a one piece works connection model, looks like these, just made by WOrks Connection,as they don't make them any more)
http://www.btosports.com/p/TMICASE
and I am guessing that either the new sprocket is thicker, or maybe it is angled, so one side is angled in or out, and they put the thing on wrong way
as before this sprocket was replaced, I had lots of clearance between the case saver and the nut holding the sprocket on
I plan to replace the o rings just to be on the safe side
any tips on installing them, never done it before
thanks again
What I was more concerned with in asking what kind of coolant you are using was some are not antifreeze (like Water Wetter) and with you living in PA it may have frozen and damaged internal parts.
My 2001 is dirty but if you look closely you can see what I am talking about.
ut my case saver is made of aluminum metal, and it was grinding up against my srpoket nut
it was so pressed against it that the aluminum metal on my case saver had about an 1/8 of an inch ground off by the bolt, and still was touching
I removed the case saver, and then add 2 washers behind it to allow for more clearance.
I plan on going back to the shop that did the install of the sporcket, and asking what the heck!
they should have noticed this when they were reinsatlling it, and seen something was wrong
I cannot get the nut loose, so i cannot tell by looking at it if the sprocket iis on wrong(if there are like to sides to it or what)
but my sprocket before , my case saver had 1/8 or more clearance from the nut
so some how I lost 1/2 plus of space there
wonder if maybe i have a wrong sprocket on
as for changing the o rings
I already ordered them, should be here this weekend
I see no harm in replacing them, and then I will know for sure if the old ones are bad or not
I also ordered new washers too
is there any tips on changing these o rings?
thanks again
But here are a few pictures of what I am talking about, you can see how the nut is cut to a clean edge face from rubbing the case saver, and the metal build up on the saver from being ground down by the nut!
thse picture are from after i placed the washers behind it, they allow clearance, but its still very close, could add more, but
didn't fix better, as I want the shop that did it to see this when I take it back to show them this weekend, and ask, double check I have the correct sprocket on and its on the right way
that spacer would only come off if the sprocket was off right
reason i ask is i had the case saver off trying to get that nut off to change the sprocket myself , just couldn't get it loose
and I didn't see any spacer, the case saver just came off in one piece, and didn't notice any spacer behind it, but then again, that area was full of several yrs of chain lube all gunked up in that area, and it just might have been stuck to the case and I didn't notice
but that would explain the gap difference now as to before!
if i run the bike with the cap off it just about 1/4 from coming out as it bounces inside.
I have been filling like this for awhile and never had any issues
so I think I am about right on how much to put in
had bike at shop, to go over the issue's at hand, and had a flywheel weight installed(huge difference, I love it)
but the sprocket they replaced is just a bunch thicker than the old, and it caused the case saver to rub
added a few washers, now Ok, as for the over heating, doesn't any more, guess it was the added resistance when that case saver was touching the sprocket nut.
have new o rings on hand, was going to replace, but plan a top end rebuild soon, so will just wiat, unles it over heats again, then will do a top ned build then or just in a few weeks when money is better!
thanks guys for all the imput!
Pit Row
what model bike is that in the picture, has me at a loss? thanks
Performed some interesting mods.......
On display in the WPS Dealer Convention booth
How it sits now but.......Not done yet..............
never rode one of the new 4 strokes, been a 2 stroker all my like, minus some of the old XR's in the early 90's, kinda like the sounds they make, as to the 4 strokes!
been hoping to ride one now I am back into riding again,(,
My Dr's not happy about this, had lot's of injurys from my young and dumber days, defienetly not in shape I was , and pains come much faster, but there still more fun to have than not!
and I miss them when I don';t have one!
Just I don't know anyone with one
But I am fasinated by the torque they have
I am not a mx racer, just a woods guy
thinks they might be a better match for me, these days, but, the price of new one's scare me!
I have been riding since 1978, and prices from then to now, WOW( then again so is everything else!)
and a few guys I know have issues with them starting all the time( think thats getting a lot better now, there's are all earlier versions of them)
but all my 2 strokes, were all low maintance and always started!
its what I know best
thanks for the pic's and your time.
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