Yep, valves are the next thing on the list. The compression test should tell the tale. Sound like you should be rolling again in no time.

 

Ok, sounds like a good next step. Can someone provide some instruction to adjust the valves for the 50 cc kazuma? If this was a small block chevy, I wouldn't need to ask how to adjust em :-)... I do have a parts / service CD I got off the internet, maybe it has the procedure. I will check that when I get home, but if anyone can provide some instruction, that would be great.
I sure hope that does the trick, I'd hate to think that the rings are shot already. The bikes only a year old. But then again, my boy rides it pretty hard.

Thanks again,

Jon

 

I do basically the same thing to set the valves on all my thumpers. I adjust all of them when the engine is stone cold. Find the TDC after the intake valves close and then adjust/check them. I put a straw down in the sparkplug hole to get to the absolute TDC. then I look for marks to confirm it. If you have the wrong TDC it can make a huge difference.

 

Here you go, a crash course in valve adjustment:

1. pull out spark plug

2. on left side of engine, take out big screw & on top the case take out the small screw, where the big screw was you can get a socket in there to turn the motor over, in the small screw if you look in there with a flashlight you will see some markings, you want to turn the motor over until you either see 2 parallel lines or 2 of these 00... this is theory should be top dead center of the piston, you can stick a screwdriver in the plug hole to see if you can feel the top of the piston.

3. take off the valve covver bolts, silver bolts one on top & one on the bottom of the head, you will see the rocker arms there, you can turn that engine over & see how they work, you want to be sure when its at top dead center that the valves are both closed, so turn the engine over with the socket to be sure they are not open...the rocker valve will move & push the valve, it should not be pushed in, should be all the way out... otherwise you are on the wrong stroke, then turn the motor over again to get it at the top again.

4. Get a feeler gauge & have the .004 piece out.... stick this in between the valve part & the rocker, ajust the rocker until you feel a little resistence & can pull & push the feeler gauge in & out of that opening.

5. Be sure to tighten the locknut back on the rocker so it doesn't do this to you again [img]i/expressions/face-icon-small-wink.gif[/img]

6. Do the other valve, exact same way

7. Replace all the covers & screws & put a new plug in the engine (I just do this out of habit, its up to you if you want a new plug or not)

8. Cross your fingers & hit the start button

9. Write us back & let us know if that worked.

Hope that works for you, any small Honda Clymer book will tell you how to do this also & probally alot better than I can... I'm no writer heh.

 

sell it and get him a used lt50 / lt80 / trx90 or something.

kazuma mini 50 quads are the biggest pos's.
seriously not worth the metal they are built out of...

my friend "had" 3 of them
here is the list of broken stuff :

gas tank petcock leaking, new tank replaced.
hard starting all the time, adjusted valves.
broke rear shock in half, new shock bought.
headlight broke, left it broke.
rear brake sucks.

and the only thing that is fun on these things is shifting it into 1st/2nd gear, holding it down, revving he engine, and letting the gear shifter back up fast, to ride massive wheelies. otherwise they are pos's.

 

Sounds like he had some bad luck with his machines.... I don't know what to say other than they have been good machines to us & alot of other people... maybe it wouldn't have broke so much if he wouldn't have been riding wheelies on a KIDS BEGINNER machine.... but who knows.... [img]i/expressions/face-icon-small-confused.gif[/img]

 

It's evident he threw them a beating. I would have to admit the 50cc is the worst of the Kazuma line but a lot of fun for a small kid.

 

Well, I kind of agree with spliffy, but I will say that I have had a few issues with this bike. Have had a broken shock and this starting problem, but other than that it has been a decent bike. 2 of my friends have them for their kids and have not had any problems at all, but I know they don't ride them as hard as my boy does. I do agree, that you get what you pay for, and I will probably look for a used 90 from one of more popular manufacturers, when he outgrows this one. But for what we paid for this bike, it outperforms everything that I thought it would. This thing has been covered in mud from head to toe and keeps on going. Brandon is 5 now and been riding it since he was 4. It goes everywhere he needs it to. Even wooded trail riding on moderate trails is no challenge.


http://forums.atvconnection.com/i/Ga...493%20copy.jpg

 

Did you get it started yet?

 

FIXED...... Thank you everyone.....

So I set out this evening to set the valve lash as suggested by spliffy and backed up by others. I pulled the plug first to see what kind of compression it had. Don't have a compression tester, so I just used the old thumb over the plug hole. It had some compression, but didn't know what to compare it with, so I proceeded. I pulled off the cap for the intake valve and couldn't get the feeler gauge in there...hmmm... I made sure it was at TDC and still couldn't get the gauge in there. It's really tight trying to get it in there. So I pulled off the exaughst cap and took a look at that valve. The first thing I noticed there when spinning the crank was that it was noticably "loose" when the valve was closed. Checked it at .004, and it was right on. Ok, lets look at the intake one again. Definately was "tight" when it was supposed to be loose. Loosened up the lock nut and adjusted the set screw, again hard to get to it, but I did manage to get it set to about .004. Buttoned everything up, and I went to check compression. MAN, what a difference. Lots of compression now. Put the plug in and it fired right up.

Going into this, I was expecting to find a valve lash that was too loose, but what I found was one that was too tight and wouldn't let the intake valve close all the way, thus lowering compression.

Thanks again to everyone who responded.

Jon (IN)