1985 Big Red 250ES turns over then locks up, turns over then locks up, wtf?

[biglsells]

OK so my recently new to me 250es was running like a champ, have had no problems whatsoever. Changed the oil and put a new carb on it when I got it and have been having fun buzzing around. I drove it into the barn the other day and turned it off. Went to start it up this morning with electric start and it turned over maybe 1 revolution and just stopped. Tapping the start button would do nothing SO I got the kick start out and went to kick it over and I couldn't, the kick lever would not go down. I then put it in gear and rocked it backwards and I could hear the engine roll over so I put it in neutral and push the kick start and it would turn the motor over the amount that it spun when I rolled it backwards but then stopped again.

I started to wonder if I had something in my engine that could have been floating around and just got loose and was jamming things up but then I sat on the bike and kept gently kicking the kick starter once it hit the point where the motor didn't want to spin and after 4 - 5 kicks (pressure applied to the lever) it finally spun over a revolution until it got to that point again. Again, pressure on the lever 5 - 6 times and it spun over.

Any ideas as to what in the world could be going on? I don't know where to start investigating.

Thanks!

[biglsells]

I'm perplexed as it was perfect when I parked it a couple days ago, started right up and drove it 10 feet into the barn and turned it off, never made any funny noises or anything then. I'll see if it moves freely in neutral and I'll pull the plug out and see if it turns over any easier like it should and post back.

[biglsells]

OK so it rolls fine in neutral. I put it in first and slowly rolled the bike backwards about 6 feet and it rolled the motor back as well no problem. Then I pushed the kick starter and it let me spin the motor over the same number of revolutions until it started binding up again! I'll try rolling it backwards further but it definitely went through a full 4 stroke cycle. What would be binding up?

[biglsells]

Got it figured out!

Pulled the plug and I could turn the engine over and over no problem but saw lots of gas spitting out of it. Took the air box cover off and the air box was 100% full of gas, it was vapor locking on the compression stroke. Awesome junk replacement carb from ebay.244776

[atc007]

Great job troubleshooting!!!!!! THANK YOU ! Send that POS back, do not let them give you any crap about the bolt! Tell them they OWE YOU money for your time. Clean/rebuild your OE carb. If you aren't comfortable with it,,,, I know you can... I can do it or Jim on here is quite familiar with them also :) lol. He has a perfect tutorial if you need any pointers. Great work and thanx again for solving it yourself !

[biglsells]

Thanks atc! I checked the oil and it's full of gas too so I'll be doing a full service on it. I cleaned the oem carb as well and plan on putting that back on the bike as well! For anyone thinking about buying one from ebay do not buy the one from seller wincycles with the ad Honda 250 Big Red ATC250ES Carburetor ATC250 Carb New (ALL YEARS)!!

[Rob Canadian]

Please do not take this the wrong way...

Could it be that something ie rust or stuff in the tank got into the carb? It would have gotten onto the needle and seat and caused this(?)

Guessing with that much fuel getting into the engine the petcock was left on(?) It does not take much of debris to not make the needle and seat to leak.

Yes I know the aftermarket carbs are hit and miss but you ran it for a bit with no issues.

[biglsells]

Tank has no rust at all and I have a inline fuel filter so I don't think any debris got in the way. Petcock was left on, I've always left them on which can be done if the carb is working properly. All is good though, I'm putting the oem back on.

[350for350]

That's why I always shut mine off. You just never know.