Kymco 500ri no compression in cylinder

[ggraven]

Okay, I got it to TDC and the intake needed a little adjusting, I could not get the feeler gauge and now I can. The exhaust side however was either way out or did not do something wrong.  I had to loosen the screw a long ways, like 1/8" to 3/16"out to where I could a feeler gauge in between the valve stem and the rocker screw. If i have this correct, I cannot see how those could be that tight. Unless some one had the cover off and tried to adjust them. I have no history with this scooter to get any info on what could have been done to it. I going to stop for a little while to see I can get any insight from you guys. Thanks for helping me so far.

[ggraven]

I adjusted the intake side valves, there was no gap i adjusted to the.004 now do i adjust the exhaust at the TDC or do i rotate 180 to the tic of exhaust valve? The exhaust side is very tight no gap even when i loosen the adjusting nut.
I would appreciate some input before I go any further.

[ggraven]

I adjusted the intake side valves, there was no gap i adjusted to the.004 now do i adjust the exhaust at the TDC or do i rotate 180 to the tic of exhaust valve? The exhaust side is very tight no gap even when i loosen the adjusting nut.
I would appreciate some input before I go any further.

[CROSSBOLT]

You DO NOT need to rotate IF you had it in the right place to start! When in the right rotation position BOTH intake and exhaust gaps should be .004" that means BOTH rocker arms should be  "rockable" like a teeter-totter. Having to back screws out an eighth to three sixteenths of an inch means you are at the wrong rotational place.

Here's the drill:

1. Remove spark plug.
2. Find a way to rotate engine
3. Rotate until piston is at top dead center (TDC).
4. Determine if piston is TDC on the compression stroke
5. Adjust all four valves to .004" gap.
6. Install and connect spark plug.
7. Gentleman, start your engine.

Hope none of the valves got bent before you got it! Ask more questions if needed. Any question will be answered. The answer may even be correct! Har, har!

[ggraven]

Well I have some good news. I did exactly what you said and I now have compression in the cylinder, pulled the plug to be sure of compression stroke and I have TDC on compression stroke. The manual says to make the the cam shaft marks are facing to the top and the T is correct on the flywheel.  The intake and exhaust valves are all set at .004 and now I have a dead battery. I had the seat off of it and the seat lock is on and ran the battery down. I have it charging. If all goes well it should start right up I hope. I did the CLEP diagnostics on it and it gave a 33 which is the fuel injector. So I have a fuel injector in case I need it. I am still puzzled why I had to back the exhaust valves so much to get a clearance. Like I said earlier I do not know what someone else may have done to it, providing no bent valves it should run.
Thanks again for your advice and help.

[CROSSBOLT]

My pleasure since it all worked! You said code 33 was fuel injector and that is the same for the DT scooter SO, make sure your fuel pump relay is consistent because it also provides power to the fuel injector! I have a post on that in the Downtown section. The service manual says NOTHING about that relay!

[ggraven]

I still cannot get the engine running, I do compression, I open the throttle body a little bit and a do get a little thumping sound from the exhaust pipe. I have spark, but it will not fire any other suggestions. I am missing something?

[scooterfan]

I still cannot get the engine running, I do compression, I open the throttle body a little bit and a do get a little thumping sound from the exhaust pipe. I have spark, but it will not fire any other suggestions. I am missing something?

Maybe you should remove the fuel injector, keep it connected to the fuel line, swing the engine by using the starter button - and see if a fine fuel spray is coming from the injector when the engine is swinging. I have no experience with scooters like yours - but that’s what I would do.

You could also just unscrew the spark plug to see if it looks “whet” after the engine was swinging a couple of times. If the spark plug looks “dry”, you obviously have a fuel supply problem, or maybe a clogged injector.
This scooter hasn't been used for quite some time, and I wouldn't be surprised if you are having a fuel problem.

The previous owner probably fiddled with valve clearances before, and just didn't manage to get the settings right. I wouldn't be too worried about it. The recommended clearance gap is very small, and even an expert can make a mistake with such small clearance gaps.

Good luck, I think you probably bought one of the biggest bargains in a lifetime.

[Stig / Major Tom]

You found some gap on the intake valve - but NO gap on the exhaust valve, yes.?

Maybe you did not do the valve adjustment correctly.....
How could it be wrong?- if you were not on the proper TDC and you then gave the exhaust valve a 'gap' by loosening the screw/nut assembly - you have now closed the exhaust valve....when the engine may not have been at the proper TDC.
You must be absolutely certain that you were on the proper stroke and at TDC of it!

You are apparently the 3rd owner who could not make this scooter run.

I think for $85 you should let the dealer take a look at your scooter. Right now it is a $300 lawn ornament.
Even IF everything is adjusted properly ....these 500's are notorious for being hard, or impossible, to start sometimes!

Stig

[CROSSBOLT]

Don't forget that code 33 you mentioned. Scooterfan said inspect the spark plug for "wet" or "dry." Wet means the injector is squirting and dry means it is not. That "thumping" you hear while cranking is normal for cranking and no firing!

[scooterfan]

I forget to mention - the spark plug might be whet but if the injector is partly blocked, or the pressure before the injector is too low , a small stream of fuel will be squirted into the combustion chamber. This could lead to a “flooding” problem.
Therefore it would be better to remove the injector, swing the engine, and then make sure that a fine fuel “mist” is coming from the injector.

You seem to be willing to learn and quite capable of getting your own scooter going in future. Just go for it.  The feeling of keeping yourself mobile,  or getting something right yourself with a little help is worth far more than $85.00.

[ggraven]

I have a question? I had spark for awhile and after adjusting valves and putting it back together I now have no spark at the plug. Did I maybe loosen something, should I replace the spark plug?

[Stig / Major Tom]

I have a question? I had spark for awhile and after adjusting valves and putting it back together I now have no spark at the plug. Did I maybe loosen something, should I replace the spark plug?

No.
Pulled the spark plug cable loose from the spark plug boot, maybe?
Tighten it by 'screwing it on' motion, righty tighty.
It's not the plug itself most likely.
You have a $300 500cc scooter.
Why NOT take it to a dealer? Pay an expert to check it for an hour, even two?
But, your call.
Some love to tinker. Some love to ride.
Stig

[ggraven]

I have everything back to working condition, I forgot to put the kickstand back up nothing was working no spark. Now the spark is back and the injector is working fine it sprays gas. I reset the CLEP for the fuel injector and it cleared. I have no error codes and it should start right up , but will not start. I had taken the throttle body off a couple of times and I am going to do a reset the throttle body. I am bound and determined to get it running, I am asking one last time for help. I have made an appointment for the 16th for a local shop that works on them. So if you any other suggestions I am all hears. Thanks to all for input so far. I am sure you guys understand the not wanting to give up when I feel I am so close to have it start.
Thanks again!!!

[ggraven]

one last thing, I noticed today that it has no air filter in the slot where it should be. Would that make any difference?