Jump to content

pitbike Help Me!

Recommended Posts

Hi everyone... i am not going the long way around this so heres a short explanation

 

I have a stomp 140 dont know if it the z140. The head gasket went and i replaced it with a better not brilliant one it had a tear on a oil pass (pic further down) :rolleyes:

I stripped the top head off making sure T on flywheel was at notch and circle on cam sprocket was at the notch when T was in line i then stripped the top head off removing the sprocket but i did not adjust the cam shaft behind the sprocket

I have then replaced the head gasket and put the top head back on. lining T to notch then the cam sprocket circle to notch (the valves in head was closed on removal and piston was TDC) now the bike runs again but really poor it back fires and wont idle even when hot and it gets real hot quick i am wondering is it a fuel mixture problem or timing out or tapets need adjusting as i did not touch them

I have ordered a new head gasket will be here wednesday

I removed the spark plug and it was a grey ish coulor which is optimal i dont know what to do really need some help thanks for any knoledge and advice

 

Pictures ...20170914_130125.jpg.518a01a15428bb2e08f04839b9bcd3ae.jpg20170914_130129.jpg.4a2cb40423ead493e4c03490efce79d1.jpg

20170914_193123.jpg

received_1842907576020494.jpeg

Share this post


Link to post
Share on other sites

you check valve lash?

 

Check Valve Lash (.003 intake and .004 exh)

 

https://tboltusa.com/store/tech.php?pID=67/Pit+Bike+Set+Up+INFO

 

here's a video from australia where they call them tappets.  Aussies are funny =)

 

Is your choke on or off?  Verify choke operation by taking off the air filter and manipulating the choke lever.  I thought by putting the choke "on" on my ssr choked the carb, however it was opposite.  Manipulating the lever actually opened the choke.

 

Other than that, mess with your idle screw, turn your air/fuel mixture screw all the way in and then one turn out.  Also, clean your carb and jets.  A paper clip and carb cleaner are your friend here.  You tube has all kinds of videos on cleaning these simple carburetors.

  • Like 1

Share this post


Link to post
Share on other sites

Hi @Azrael888 thanks for the reply.

My choke is defintly off and have cleaned the carb to many times i have had some luck though dont know if it is good luck as i have now found the problem after a new head gasket change.

I checked my valves and tappets (im from uk so we call them tappets too lol)

And i have diagnosed that my intake valve is gone, i can spin the valve 360 degrees and wobble it side to side. To back up this theory of mine i put petrol in the intake manifold with the valves at the top of compression stroke so both were closed and it leaked out really quick.

I also youtube'd how to check valves and it showed putting a torch to them and looking through the manifold to see if there was light and there was at least half of the valve! :(

Now my concern is how do i change out the valve i googled it and it said i could need my head taking to machine shop is this true? Would it be cheaper getting a new head?

Thanks i am looking forward to your reply

20170920_152820.jpg

20170920_152808.jpg

Share this post


Link to post
Share on other sites

your best bet is going to be a new head.

 

However much that will cost you I'm not sure.

 

If you want to try and fix it yourself you're going to have to take out the valve. (Youtube is your friend here) verify that the valve guide isn't torn up from the valve being bent. which honestly if there is damage to the the valve it's generally because of contact with the piston. 

 

if you get a new valve you;re going to have to seat it and there are videos on how to do that yourself as well but i've never done that.  Essentially you could be $100 bux into this engine faster than you can sneeze trying to fix it when you might be able to spend $150 (or less no idea on what new heads cost for these bikes) and just be done with it.

 

they're out of stock but this:

 

https://www.ooracing.com/head-kit-yx-140-stomp-and-dirt-max-big-valve-standard.html

 

Share this post


Link to post
Share on other sites

Thank you @Azrael888 i am just going to save up for a new head as i also have never touched valves cam etc, heads are pretty cheap tbh i can pick up a standard one for about £70 $80 or get a zx140 race cam and valves for about £100 $110

So its not too bad

thanks for your help :thumbsup:

Share this post


Link to post
Share on other sites
On 9/20/2017 at 1:47 PM, Azrael888 said:

you check valve lash?

 

Check Valve Lash (.003 intake and .004 exh)

 

https://tboltusa.com/store/tech.php?pID=67/Pit+Bike+Set+Up+INFO

 

here's a video from australia where they call them tappets.  Aussies are funny =)

 

Is your choke on or off?  Verify choke operation by taking off the air filter and manipulating the choke lever.  I thought by putting the choke "on" on my ssr choked the carb, however it was opposite.  Manipulating the lever actually opened the choke.

 

Other than that, mess with your idle screw, turn your air/fuel mixture screw all the way in and then one turn out.  Also, clean your carb and jets.  A paper clip and carb cleaner are your friend here.  You tube has all kinds of videos on cleaning these simple carburetors.

Good advise here !!

  • Like 2

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Reply with:


×