my new 250r! gone bad!!!

[yeppimcody]

I just bought this 250r the guy i bought it from said he has only put a tops of 4 hours on it. so today i was riding it out on the lake and thenwham it cesed up. i tryed to kick it over i couldnt evean move the kick start to save my life. i let it sit for about 10 min. i went to kick it. it kicked right over with wat seem like no compresion like it had no spark plug in it. now i can hear the rings squeeking inside of the cilinder....... i was running 40:1 honda 2-stroke oil in it please help.... i will post pics asap.

[leviblue]

SideWayz had the same thing happen to him last month. Whole new top end for him. He's got a wiesco piston and rings if you need it, brand new in the box. Give him a shout man....

[yeppimcody]

F*&%!!!!! this blows alright thanks man.

[tecat-z]

Lean fuel condition will kill it every time. I introduce lots of fuel to my engine in the cold. 40-1 is not the problem.

[yeppimcody]

i just wen tand looked and from it sitting the boot connecting the carb is cracked and theres abig gap soo lots of air got in to it! ahh not funn whats the best mixture to run when i get it going agin???

[tecat-z]

You can sieze an engine weather it's 20-1 or 50-1. It has to be jetted properly!! Correct jetting is more important than the fuel/oil ratio. 32-1 is generally considered acceptable by most.

[jays375]

I wouldn't put the whole blame on yourself.You said it had only four hours on it.Did it have a bore and new piston or just a new piston.You will know when you tear it down.Looks like a aftermarket pipe on it.Maybe it wasn't ever set up right with jetting.That is why I am always leary of a just rebuilt motor without any hours on it.Seen alot of people throw something back together for few hundred dollars.That way they can sell it for more than just a parts machine.Maybe he got boned on it from somebody else and passed it on.Keep track of your new carb boot after you rebuild.Aftermarket ones seem to break down quick.It was the boot between the carb and motor,not to the airbox?

[yeppimcody]

yea its an after market dg and the guy i bought it from said as far as he knows no rebuld or or bor... and he said the orginal owner wasnt much smater then to beabel to put gas in the thing. so mabe he slaped on the pipe and never jetted it...any advice weather or not if i can keep it the same or just bore it outif so how much?

[jays375]

You won't know until you tear it apart.Then you will be able to see what you have.The piston will be marked 10,20,30 if it was bored out.That is how much it was already bored

[yeppimcody]

yea well im gunna get at it as soon as i get off of work tomrrow and start spendin m ore money:/

[harryredtrike]

dude that harsh,tough luck.when buying something off someone you have to cross your fingers for awhile.when i got my 250r he said the same thing and i was like greaaaattt

[Twilight]

Well if there was an airleak you have a rebuild of the top end and a new carb boot on order, if you know how to I suggest rebuilding the top end and new seals in the bottom end with new bearings.

I bought my old pilot and after 3 weeks it blew, from that day On I rebuilt every 2 stroke if the compression and airleak test failed within the manuals specs.

[Side Wayz]

Sent you a PM.

[audioworks04]

Like twlight said I would do a top end rebuild (bore next over with new piston, rings, wrist pin and bearing, and circlips) may be able to do just a hone, but will most likely need a piston and all the other parts still, wont know until you take it to a machine shop and have it mic'd. Also the seals in the bottom end are highly recommended, if they leak they will also cause a new condition. Make sure when re assembled to use all new gaskets with a good gasket adhesive if needed such as 1211 or yamabond. Make sure to follow manufacture specs on torque specs, along with all other assembly instruction and use lots of lube (2 stroke oil works good, or what ever you run in the bottom end). For break in I like to ride it around at a mild pace and try to keep it above idle as much as possible. After half a tank of fuel you should be good. No need to run a different pre mix oil than normal just run it a little richer. After you ride for a while pull the plug and look at it closely, it should be a nice chocolate brown color, if not then your jetting is off. White= too lean, black= too rich

[yeppimcody]

i took it apart to night my rings a totaly gone and took a chunk or two out of the piston im gunna need to get it bored it was never bored so im gunna bor it over .10 or .20. im redoing the bearing,wrist pin and circlclips. with new rings and piston of couse. i dont have tim money or knolage enuff to re do botom end seals but i look ss at the carb boot and it was not on all the way and is cracked! so will be ording a new one also. thanks for all the replys. i will post picks of it later tonight

[RodKnockRacing]

seems to me what happened is the cracked intake boot sucked to much air and caused it to lean out but u should check your crank seals because if they are bad you are gonna run into the same problem of it sucking air and leaning it out but good luck with her man

[yeppimcody]

well her is whats left of the piston. http://i169.photobucket.com/albums/u234/yeppimcody/honda250rrebuild020.jpg could any body tell me what the white powder is? or is it just burnt rings and piston? http://i169.photobucket.com/albums/u234/yeppimcody/honda250rrebuild019.jpg the r tor down almost all the way. http://i169.photobucket.com/albums/u234/yeppimcody/honda250rrebuild023.jpg the shavings that came out of the pipe http://i169.photobucket.com/albums/u234/yeppimcody/honda250rrebuild024.jpg would this cause the air leak? http://i169.photobucket.com/albums/u234/yeppimcody/honda250rrebuild026.jpg thanks for all the help guys!

[leviblue]

white powder is alum. looks like sidewayz's good luck with her

[mart]

White powder is the piston getting so hot and melting (liquid aluminium) And probably the last thing you want to here is i prob would build the bottom end because a blow up like this usually sprays the main bearings with alloy and the big end (conrod bearing)you just might build the top and get lucky and get away with it but there would be nothing worse than it runnin for another few hours and lockin up the mains or the big end gets messy trust me lol.Deffinately sort out why and what is causing her to lean out because left untreated its only goin to do it again.good luck with it mate dont give up youll love it when its flat out fith gear.(and not runnin lean)

Also just a quick thing you might wanna check that carb aint keihn looks like a mikuni tmx dont qoute me on that you might deff wann check jetting.And i dont think thats a dg pipe looks like an old ct style pipe

[yeppimcody]

yes it is an old mikuni carb not shure what make but how do i check the jetting? also would the gap/crack in the boot cause it to lean out??? aor does any body have and old 250r stock carb thanks guys!!!

[eyecekold1]

The "jetting" is the size of jet in your carburetor. To find out what you have you need to pull the bowl (or bottom) off the carb and you will have brass jets on the bottom part of the top end of the carburetor the main jet should be octagonal in appearance or could just be round with a straight groove in it (so you can take it out with a standard screw driver) once you get that jet out look at the little number stamped on it. You need a larger number jet they get bigger in increments of 2,3,and 5 I would skip up 2 or 3 sizes just to start and buy 3-4 in bigger sizes. (jets are at the local cycle shop) To jet the bike (make sure you have the motor broken in) you will want to run it in 3rd or 4th gear pinned for like 20-30 seconds straight. Then stop the bike pull the spark plug and see what color it is. If its white I would jump up at least 2 sizes if its black down one. If it is the color of card board your good. Know that changes in temperature and elevation changes your fuel needs and you will need to check the plug the same way when either one changes. I would say one jet setting for fall winter and one for spring summer. One way to tell if your running rich is that the bike will cut out and run weird at high rmp, this is because you have too much fuel if you run lean it may do the same thing, lean can also run like normal. Jetting is a pain but it gets easier as you do it more.
No need to change your carb its better than an OEM carb most likely all you need is jetting.
That break in the boot shouldn't affect your air intake but its a good idea to get a new one.
Good luck.

[AutoXer]

I know it sucks spending money but all that hot aluminum floating around did get to your low end and contaminate the bearings. Have that rebuilt or buy a running motor for now and get the one that was in there and build it as you have money my .02

[mart]

YEh that crack doesnt look to bad but would deffinately change as its on the way out.Im pretty sure it wouldnt of caused this lean condition altough this is over a computer and i cant tell how far that crack goes but seems if its cracked there its prob getting hard and brittle any way.best way is to do a pressure test on the engine before you do any jetting and find the cause sure it may just be to small jets but dont just jet rich to componsate for a problem such as an air leak find the source first then jet it,.Also plug chops are only good to test your main jet you still have to dial in pilot jet and needle (mid range 9 out of ten times people do a plug chop get the right coulour than say my bikes jetted perfect two days later there piston looks like yours,(soz i dont mean that in a bad way) most of the time from runnin wide open throttle than lettin it off 2 strokes wirst night mare havin all that cool fuel than shut off goes back on the pilot jet circut still at high rpm's then seizes, just make sure when you build her again.NO matter how you do it just when its runnin again find the cause and jet it correctly If your un sure get some one that knows how to to do it.cheers