Motor smokes Bad

eat dirt · Nov 6, 2009

I am starting a new thread because this topic got brought up at the bottom of my last thread and i am looking for more input.

So i bought a used Honda 50 motor with newly installed takagawa 88cc Stage S (conclusion of you guys) kit, "supposidly" new ran less than an hour... he said it smoked and thought it needed new seals.... well from the sounds of it some of you guys thought that the top end may be bad?? When I ran the bike it still felt like it had good power but just smokes a shat-ton to say the least.... just wondering what some thoughts are on this as i am new to these bikes.....Valves?? Top end?? Other??

Thanks in advance

taz69 · Nov 6, 2009

MOST of the time smokeing like that is the oil seal around the valve stem is gone or going bad.. NOT the valve seat but there is a rubber seal that is under the springs that keeps oil from going down the valve shaft.. If it does it more under deceleration ( pullin some upper revs and then letting off) If it smokes more like that its the seals.. If it smokes on the gas then its the piston, rings, cylinder one of those things... But if you close the trottle while rideing and it smokes its the seals.. Look and make sure the vent tube is not blocked though.. Back pressure in the engine will make it smoke...

50rider340 · Nov 6, 2009

If it is brand new as the guy said as in a hour its a good chance he put the rings in upside down. If thats the case then it will run fine but smoke like hell. you could take the top end apart and check the rings, You may still be able to see the little letters on the rings those face upwards. Also check and see how much scoring is on the cylinder walls and piston. When you take it apart definitely post pictures as that will help a top for people to help.

schofell84 · Nov 6, 2009

check for gas in the oil, that makes a ton of white smoke. tee hee

LongMooie · Nov 6, 2009

check the rings for sure i remember when i got my takegawa 124+R kit the first batch of those kits got shipped out with the wrong piston rings

i didnt notice and installed them when i fired it up it smoked really bad lol

thinking it was just the oil i lubed the piston out with i rode up and down the street with a hude trail of smoke lol

new rings and i was set

trd20 · Nov 7, 2009

Definitely check your rings, this happened on my 250f. It ran great but smoked all the time, but i decided to let it go. A few hours later I needed a new cylinder and piston.. not good

eat dirt · Nov 9, 2009

i think im taking the bike tonight to a family friend who has been building bikes/doing small engie work for the past 35 years. Im hoping its just the rings are the wrong way or something simple! With work and school I just havent had the time to pull it apart, and he wont charge squat for labor.... Ill keep you informed about what they find out... worse case what would a top end cost?

trd20 · Nov 9, 2009

If you end up only needing new rings or a new piston and rings, it won't cost much, probably around 50 bucks or so. As long as your cylinder is okay and doesn't need honed, it should be a simple and relatively cheap fix.

dirtbkr188 · Nov 9, 2009

Also make sure the ends of the corrugated oil wipe ring are not overlapped, preventing the ring from expanding under heat, and allowing the oil to get up into the combustion chamber.

eat dirt · Nov 9, 2009

hopefully that it a cheap fix... that way i dont feel like i got ripped off any more...lol... but i appreciate the help you all have given me... hopefully the bikes will be back up and running good by the end of the week....

723Racing · Nov 9, 2009

eat dirt said:
I am starting a new thread because this topic got brought up at the bottom of my last thread and i am looking for more input.

So i bought a used Honda 50 motor with newly installed takagawa 88cc Stage S (conclusion of you guys) kit, "supposidly" new ran less than an hour... he said it smoked and thought it needed new seals.... well from the sounds of it some of you guys thought that the top end may be bad?? When I ran the bike it still felt like it had good power but just smokes a shat-ton to say the least.... just wondering what some thoughts are on this as i am new to these bikes.....Valves?? Top end?? Other??

Thanks in advance

Dude thats got to be your top end. I dont see how it could be anything else. Your not running two stroke gas right? (pre mix) Unless maybe the didnt use new gaskets when rebuilding it. You can take your rings off the piston and mic them to see if they are in spec. If i were you, id get a top end kit, INLUDING gaskets. That should fix it. Go to Tboltusa.com and talk to Vince. Those guys will take care of you

eat dirt · Nov 10, 2009

i emailed the guy i bought it from an he said he went thru 3 top end kits tring to solve the problem. he swear the rings are on the right was ant narrowed it down to the valves. Again im taking his word on it, but until i get it checked out im not going to throw money at it trying to guess whats wrong...ill just not rid it until its fixed so no more harm is done... and i havent put gas in it i just swaped motors froma lifasn to the current motor.

taz69 · Nov 10, 2009

I told you guys at the beggining of this thread.. Its the valve SEALS that are worn and leaking oil.. Its going down the valve stem and burning off when then the valve opens.. Seals valve seals not rings nor piston its the seals.. Not seats but the seals lol... Check the valve guides as well if its a slightly bent valve it could have worn the guides so just check them...

eat dirt · Apr 1, 2010

has a new piston and ring put on early winter... seals checked out the guy said who worked on it... and im running it now that the snows gone and it still smokes like a son of a B/tch

Motor smokes Bad

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