200s compression really high.

[MonkOFox]

Ok, so I took the motor out and took the spark plug out and the cdi stuff. I pull on the starter and it was smooth as can be. So I was like, hmmm. So I put the spark plug back in and viola, hard to start again and really really hard almost knocked the motor off the table not expecting it. So I tore it down anyways and there are no obstructions, everything looks good...

Here are the pictures I took:



Could the dirtiness on the valves/piston cause it? The timing looked good. I did the T/O thing and then the F and lines on the pulse generator and the part that slides on the cam, stator, that's it. Now, I did mark the letter and not the line with a circle above it, could 1 tooth off or so make it harder, that much?

Also, I inspected the tappets and they were compressing the valves like the should, even when the spark plug was in and harder to pull. I'm confused... With the valves opening and closing that compression shouldn't be that high. Don't even think I could kick start that thing...

Thanks.

[MonkOFox]

I cleaned the valve... combustion chamber and the piston:

[MonkOFox]

I'm starting to think it has to be the valve clearance. I'm going to adjust them closer. Maybe the valves aren't opening enough. It's pushing the pin and the spring is compressing though. That's the only different part I have as well.

[Dirtcrasher]

What is the PSI??

Was the rubber plug behind the cam journal installed?? If not the cam doesn't get enough oil.

You are running rich, def carboned up...........

[MonkOFox]

Yeah I never cleaned it before. And didn't adjust the fuel mixture screw list supposed to. I'm going to adjust the valve clearance and hopefully the compression is so high. Then I'll test it. If I can't turn it over, lean or rich is the least of my worries. I'll post pictures of how I reassembled.

[MonkOFox]

Here are the steps I took:

Put the bushing in:



Put the plug in:



Oiled everything: the pocket and springs.

put the cam in lobes down with sprocket on and chain:



Then aligned the T and O marks like said in manual:



put the gasket stuff on the cover:



Put the cover on and finger tightened until the stuff just started to ooze out and am currently letting it set up for 1.5 hours:

[MonkOFox]

I think I found the problem as well:



The clearance is like 2.5 - 3mm. Don't know if the person that parted this out did this or what or if the previous owner had longer valves or something?? Anyways it's definitely not .05mm like it's supposed to be.
So I'm thinking that's the reason it was so hard to turn over when the spark plug was in, the valves weren't opening enough.... I'll adjust them and put the plug in at about 9:15 and see it's any better.

[MonkOFox]

How long should I wait for the silicone to set up before I actually try to start the machine? Full 24 hours?

[Dirtcrasher]

Yes.... 3 bond or similar, just use a tad less and stay back off the journals per spec in the shop manual. Aftermarket cams need .002-.003 additional gap @ the rocker setting if it is not stock.

[Yamaha_Rules69]

I usually start it a couple hours after applying the sealant, but I use Hondabond, and it sets up fast. Be sure to get a feeler gauge, YOU NEED IT, you can pick one up at any auto parts store. They are made of thin metal, there are like 30 of them on one stick, all different thicknesses, select the right size, I believe its .003 inches both intake and exhaust, but check manual to be sure. Its a VERY small gap there, you'll never get it by eye. Its a little tricky the first couple times, but it will become easier after you do it a few times. You want there to be a slight drag on the feeler gauge, not too tight or loose. You have to adjust the gap by turning the square nut in or out, and the nut is to lock it tight. Turn the square part above the nut in with the feeler gauge in between, until there is slight drag when moving in and out. Hold the square nut in place, and carefully tighten the lock nut. Double check your work to make sure its right. If you don't have the special square wrench to hold the square part, use a needle nose pliers to hold it. This is the way I do it, as I do not have that tool, but this method works alright.

[MonkOFox]

The cam, valve/spring and rockers are all stock. I don't know why the tappets were so far out though. I don't have any feeler gauges, just going to do it by touch.

haha, nvm, feeler gauge it is.

[MonkOFox]

Yeah I have a smaller 10mm wrench and it will box on there enough to loosen/tighten. Are those feeler gauges super flimsy? So it can go over, vertically down and then between the tappet and valve? Or do I specifically need to find bent gauges?

[MonkOFox]

It's .05 mm for this particular motor. At least that's what the book says.

[MRSOUND]

Feeler gauges will be "flimsy' on the smaller thicknesses. Think of this way, an average piece of paper is .004 -.005 thick. .05 mm is approx .002

[Yamaha_Rules69]

Yes, the gauges are flimsy, and able to bend just right. I was talking about inches, its 3 thousandths or .003in, I wasn't talking mm's. I live in the USA and use inches to measure, dosent the manual give an inches measurement, it usually gives both side by side? You could use a piece or regular notebook paper as a feeler gauge, it is .003in. Otherwise, just do it the right way and get the feeler gauge. Good luck, and let us know what happens!