Planet Minis

79z50420 · 11-24-2007, 02:59 PM

Ok i bought this bike off a guy that said it was low on compression and before it quit it was smoking a little so we both thought it was the rings...i installed the new rings and still nothing...i got lots of spark but it wont fire...not sure where to look, maybe the valves are outta wack? Oh and also when installing the rings which one is the top ring? the black one or the silver?

tmas · 11-24-2007, 03:34 PM

Install the lower piston ring (which is flat black in color) onto the lower groove in the piston. After the lower ring has been installed, install the upper ring, which is shiny in appearance.
tmas

check link for technical help.
Technical --Dano's Bike Shop-- 50cc MotoX, Fifty, Fiddy, Minibike Information Source

arlindsay1992 · 11-24-2007, 04:36 PM

Valve seals could be gone causing the bike to burn oil. Valve clearances could be so tight that the valves never close completely causing low compression. The rings could be installed upside down, or in the wrong order or both. This shouldn't really make a noticeable power loss or burn oil but it's not right. If you didn't hone the cylinder before installing the rings, the rings will never seat and you will get low compression and possibly blow by.

79z50420 · 11-24-2007, 05:52 PM

Quote:

Originally Posted by tmas

Install the lower piston ring (which is flat black in color) onto the lower groove in the piston. After the lower ring has been installed, install the upper ring, which is shiny in appearance.
tmas

check link for technical help.
Technical --Dano's Bike Shop-- 50cc MotoX, Fifty, Fiddy, Minibike Information Source

Cool man thanks for the link...i guess i ended up installin the ring backwards, shiny one on the bottom and black on the top. Can i just pull it apart and re-install the rings the correct way or did i screw them?

79z50420 · 11-24-2007, 05:55 PM

Quote:

Originally Posted by arlindsay1992

Valve seals could be gone causing the bike to burn oil. Valve clearances could be so tight that the valves never close completely causing low compression. The rings could be installed upside down, or in the wrong order or both. This shouldn't really make a noticeable power loss or burn oil but it's not right. If you didn't hone the cylinder before installing the rings, the rings will never seat and you will get low compression and possibly blow by.

Well i just came in from cleaning the valves and it did make a differerence in the compression, i got a lot more for sure but still no start. I'm thinking its the carb since the plug isn't getting wet as the gas is pouring straight out the overflow hose. I adjusted the float but then when i open the drain screw by the overflow hose nothing comes out...is this right?

OUCR250R · 11-24-2007, 06:21 PM

Sounds like you definitely have a fuel delivery issue. Take the carb apart and completely clean it out. Make sure every venturi is open. After that I bet you will be good to go.

79z50420 · 11-25-2007, 02:37 PM

ya i cleaned it out a bunch of times....like i blow into the fuel inlet hose and its clear then i press up the float and it closes like it should. Like i get it to not take any fuel it seems or taketoo much and over flow. i think its a bad seal on the jet.

79z50420 · 12-02-2007, 01:18 PM

Ok i pulled the head and cly. and installed the rings the right way and i still cant get it to fire.

I'm making lots of compression as i can feel it when i pull the plug, i got good spark with a new plug should have air because it sucks in the carb when you kick it over. The only thing now is i can;t get the float level right on the carb..it just drains outta the overflow. I even put a little gas in where the plug goes to see if it'll fire up but nothing.

I read some other thread about a similar problem and it ended up being the valves were set too tight and not closeing all the way. I'll have to pick up a feeler gauge this week and try setting them to .002 as the manual says. Anyone else have any ideas on why it wont run?

arlindsay1992 · 12-02-2007, 07:26 PM

Could be a carburetion issue still or might be the ignition timing is way off. Sparking way early or way late.

79z50420 · 12-03-2007, 01:59 PM

Ok for the ignition timing it's just lineing up the T mark on the flywheel with the O mark on the cam sprocket right? I got that set to half a tooth before the notch where i was told it works better.....and it's set with the valves closed and at TDC i'm pretty sure.

oh and would it make a huge deal if the bike has been sitting covered outside for week in the cold?

arlindsay1992 · 12-03-2007, 03:27 PM

What you said was the cam timing. And it sounds right. Ignition timing is the point at which the spark comes to ignite the fuel mixture. And it sitting should only make it hard to start if anything. But it shouldn't stop it from running.

davez · 12-03-2007, 06:38 PM

maybe the needle and seat in your carb is worn. take the carb fully apart and soak it in cleaning solution, then blow out all the passages with compressed air, then reset your float level after installing new needle and seat

79z50420 · 12-04-2007, 02:56 PM

Quote:

Originally Posted by arlindsay1992

What you said was the cam timing. And it sounds right. Ignition timing is the point at which the spark comes to ignite the fuel mixture. And it sitting should only make it hard to start if anything. But it shouldn't stop it from running.

Cool i'll have to check that out....i just read how to do it in the manual so that should cross one more thing off the list.

79z50420 · 12-04-2007, 03:01 PM

Quote:

Originally Posted by davez

maybe the needle and seat in your carb is worn. take the carb fully apart and soak it in cleaning solution, then blow out all the passages with compressed air, then reset your float level after installing new needle and seat

Ok i'll have to pulll it apart tomorrow night and give it a good clean. Not sure how to change out the seat tho as i think it's built into the carb but i'll buy a new needle. First i'll just clean everything....when settting the float to the .5" how do take that reading? From the bottom of the float where the pin goes to the carb body?

79z50420 · 01-02-2008, 09:36 AM

BUMP!! I still can't seem to get the bike to fire or sputter or anything...I set the ignition timing to .013" at the T mark like the manual says and there is gas getting to the plug, cam timing is right and there is compression. I'm kinda running outta options and getting fustrated, any sugestions would be helpful.

arlindsay1992 · 01-02-2008, 09:39 AM

Are you getting spark? Check the coil. The manual shows how to do it.

Lair · 01-02-2008, 09:55 AM

Are you sure you have the points gap set correctly?

davez · 01-02-2008, 06:07 PM

buy a new carb from Dr.atv for cheap

79z50420 · 01-03-2008, 04:22 AM

I have lots of spark for sure and as for the point gap it's set to what the manual says between .012-.016" at the T mark or i think it's supposed to done at the T mark. You set it when the gap is opened the most just before it starts to close don't you? And should there be any pull on the feeler gauge when checking it?

arlindsay1992 · 01-03-2008, 04:32 AM

Set it at the T mark. Should be just a hair of resistance on the feeler gauge. Are you sure the spark plug is good? Sometimes you may not be able to see that the insulator is cracked. And that may cause the spark to be visible but not sufficient for the engine to run. Are you sure your carburetor is adjusted correct? How do you KNOW that gas is getting to the plug? Is your air filter clean? Just putting out more stuff for you to check, but it sure seems like based upon the information you gave the bike should run.

11-24-2007, 02:59 PM	#1 (permalink)
79z50420 PM Newbie Join Date: Nov 2007 Location: East Coast Canada fackers!! Posts: 96	can't get 79z50 to run after new rings installed Ok i bought this bike off a guy that said it was low on compression and before it quit it was smoking a little so we both thought it was the rings...i installed the new rings and still nothing...i got lots of spark but it wont fire...not sure where to look, maybe the valves are outta wack? Oh and also when installing the rings which one is the top ring? the black one or the silver?

11-24-2007, 03:34 PM	#2 (permalink)
tmas ZB50 Jedi Join Date: Apr 2005 Location: Toronto Posts: 4,108	Re: can't get 79z50 to run after new rings installed Install the lower piston ring (which is flat black in color) onto the lower groove in the piston. After the lower ring has been installed, install the upper ring, which is shiny in appearance. tmas check link for technical help. Technical --Dano's Bike Shop-- 50cc MotoX, Fifty, Fiddy, Minibike Information Source

11-24-2007, 04:36 PM	#3 (permalink)
arlindsay1992 "High Speed Record Guy" Join Date: Mar 2006 Location: Northern Virginia Posts: 4,369	Re: can't get 79z50 to run after new rings installed Valve seals could be gone causing the bike to burn oil. Valve clearances could be so tight that the valves never close completely causing low compression. The rings could be installed upside down, or in the wrong order or both. This shouldn't really make a noticeable power loss or burn oil but it's not right. If you didn't hone the cylinder before installing the rings, the rings will never seat and you will get low compression and possibly blow by.

11-24-2007, 06:21 PM	#6 (permalink)
OUCR250R 2nd Gear Member Join Date: Feb 2007 Location: Norman, Oklahoma Posts: 288	Re: can't get 79z50 to run after new rings installed Sounds like you definitely have a fuel delivery issue. Take the carb apart and completely clean it out. Make sure every venturi is open. After that I bet you will be good to go.

11-25-2007, 02:37 PM	#7 (permalink)
79z50420 PM Newbie Join Date: Nov 2007 Location: East Coast Canada fackers!! Posts: 96	Re: can't get 79z50 to run after new rings installed ya i cleaned it out a bunch of times....like i blow into the fuel inlet hose and its clear then i press up the float and it closes like it should. Like i get it to not take any fuel it seems or taketoo much and over flow. i think its a bad seal on the jet.

12-02-2007, 01:18 PM	#8 (permalink)
79z50420 PM Newbie Join Date: Nov 2007 Location: East Coast Canada fackers!! Posts: 96	Re: can't get 79z50 to run after new rings installed Ok i pulled the head and cly. and installed the rings the right way and i still cant get it to fire. I'm making lots of compression as i can feel it when i pull the plug, i got good spark with a new plug should have air because it sucks in the carb when you kick it over. The only thing now is i can;t get the float level right on the carb..it just drains outta the overflow. I even put a little gas in where the plug goes to see if it'll fire up but nothing. I read some other thread about a similar problem and it ended up being the valves were set too tight and not closeing all the way. I'll have to pick up a feeler gauge this week and try setting them to .002 as the manual says. Anyone else have any ideas on why it wont run?

12-02-2007, 07:26 PM	#9 (permalink)
arlindsay1992 "High Speed Record Guy" Join Date: Mar 2006 Location: Northern Virginia Posts: 4,369	Re: can't get 79z50 to run after new rings installed Could be a carburetion issue still or might be the ignition timing is way off. Sparking way early or way late.

12-03-2007, 01:59 PM	#10 (permalink)
79z50420 PM Newbie Join Date: Nov 2007 Location: East Coast Canada fackers!! Posts: 96	Re: can't get 79z50 to run after new rings installed Ok for the ignition timing it's just lineing up the T mark on the flywheel with the O mark on the cam sprocket right? I got that set to half a tooth before the notch where i was told it works better.....and it's set with the valves closed and at TDC i'm pretty sure. oh and would it make a huge deal if the bike has been sitting covered outside for week in the cold? Last edited by 79z50420; 12-03-2007 at 02:18 PM.

12-03-2007, 03:27 PM	#11 (permalink)
arlindsay1992 "High Speed Record Guy" Join Date: Mar 2006 Location: Northern Virginia Posts: 4,369	Re: can't get 79z50 to run after new rings installed What you said was the cam timing. And it sounds right. Ignition timing is the point at which the spark comes to ignite the fuel mixture. And it sitting should only make it hard to start if anything. But it shouldn't stop it from running.

12-03-2007, 06:38 PM	#12 (permalink)
davez 2nd Gear Member Join Date: Dec 2005 Posts: 769	Re: can't get 79z50 to run after new rings installed maybe the needle and seat in your carb is worn. take the carb fully apart and soak it in cleaning solution, then blow out all the passages with compressed air, then reset your float level after installing new needle and seat

01-02-2008, 09:36 AM	#15 (permalink)
79z50420 PM Newbie Join Date: Nov 2007 Location: East Coast Canada fackers!! Posts: 96	Re: can't get 79z50 to run after new rings installed BUMP!! I still can't seem to get the bike to fire or sputter or anything...I set the ignition timing to .013" at the T mark like the manual says and there is gas getting to the plug, cam timing is right and there is compression. I'm kinda running outta options and getting fustrated, any sugestions would be helpful.

01-02-2008, 09:39 AM	#16 (permalink)
arlindsay1992 "High Speed Record Guy" Join Date: Mar 2006 Location: Northern Virginia Posts: 4,369	Re: can't get 79z50 to run after new rings installed Are you getting spark? Check the coil. The manual shows how to do it.

01-02-2008, 09:55 AM	#17 (permalink)
Lair 2nd Gear Member Join Date: Nov 2007 Location: Birmingham, AL (Not a native.) Posts: 401	Re: can't get 79z50 to run after new rings installed Are you sure you have the points gap set correctly?

01-02-2008, 06:07 PM	#18 (permalink)
davez 2nd Gear Member Join Date: Dec 2005 Posts: 769	Re: can't get 79z50 to run after new rings installed buy a new carb from Dr.atv for cheap

01-03-2008, 04:22 AM	#19 (permalink)
79z50420 PM Newbie Join Date: Nov 2007 Location: East Coast Canada fackers!! Posts: 96	Re: can't get 79z50 to run after new rings installed I have lots of spark for sure and as for the point gap it's set to what the manual says between .012-.016" at the T mark or i think it's supposed to done at the T mark. You set it when the gap is opened the most just before it starts to close don't you? And should there be any pull on the feeler gauge when checking it?

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01-03-2008, 04:32 AM	#20 (permalink)
arlindsay1992 "High Speed Record Guy" Join Date: Mar 2006 Location: Northern Virginia Posts: 4,369	Re: can't get 79z50 to run after new rings installed Set it at the T mark. Should be just a hair of resistance on the feeler gauge. Are you sure the spark plug is good? Sometimes you may not be able to see that the insulator is cracked. And that may cause the spark to be visible but not sufficient for the engine to run. Are you sure your carburetor is adjusted correct? How do you KNOW that gas is getting to the plug? Is your air filter clean? Just putting out more stuff for you to check, but it sure seems like based upon the information you gave the bike should run.