Couple Questions about the 01 426

Well i got an 01 426 day before yesterday and it was running and starting fine. after 2 rides. Then I shut it off for about 30 min and came back out to take another quick spin on it and and took me like 20 to 30 kicks to get it started. So i decided that I would change the spark plug. Got it all changed and it wouldn't even start. So that one problem but I went out today to try to start it again and now it feels like it lost all kinds of compresion. I can roll it over with my hand and the compression release is releasing all the way. It is in time. I dont know what else to do. But i did notice that there is a hole on the side of the cylinder where i can feel it sucking in and blowing out air. Here is the pic.

000_0030.jpg

That hole is the drain port for the spark plug well. It's main purpose is to keep oil from a leaking cam cover gasket, or water from outside, from building up in the plug well.

If you can feel air moving in and out of that hole, it's likely that your spark plug is loose or broken.

what about my compression problem

You might think about tightening your spark plug and see if you still have a problem.

i know it not that. the plug is tight when i put it in. im not worried about the hole now its something else. I took the valve cover off and it is in time and the chain is tight also.

Did the plug thread in for ever before it got tight? If the plug just stopped after a turn or two it may be hung up or cross-threaded. I would count the number of turns required to remove the sparkplug and compare that number to the number of threads on the plug. It should work out to the exact same number, since the plug barely goes into the chamber. If it were me, I would look at the last thing I did before it stopped working and work backwards. If all that you did was change the plug, and now it doesn't have compression and air blows out where the plug drains, that would be an indicator to me that just maybe the plug wasn't installed correctly, or the wrong plug was put in. Easy enough to check, anyway.

well i tightened the plug up all the way and there is no air blowing out the hole and i still have no compression. Also really the last thing i did was take out the air filter and kick it over a few times, thats when i found out it had no compression.

Maybe you didnt read that right, THE SPARK PLUG IS NOT THREADED IN THE HEAD CORRECTLY!

Just incase you have any questions, CHECK THE SPARK PLUG.

AGAIN< YOUR SPARK PLUG IS THE PROBLEM

hope you understand that now. if not remove your spark plug and put a new CR8E plug in the bike.

And since you are working on the spark plug, make sure you have the Yamaha tool to get to it: 5BE-2814F-00-00

man the plug is tightened all the way i made sure. and it is a new plug also. Also it did take a while to put it in.

i know it not that. the plug is tight when i put it in. im not worried about the hole now its something else. I took the valve cover off and it is in time and the chain is tight also.

What are the valve clearances?

thats what we are checking tomorrow. Would that cause it to not have compression.

thats what we are checking tomorrow. Would that cause it to not have compression.
Answer the question, and I'll tell you.

alright just used the feeler gauge to check the valves and the intake is .10 and the exhaust is .20

All 5 of them are like that?

guh i should have thought about that. i have to take the cams out to be able to check all of them don't I?

Absolutely not! You are checking the clearance between the cam and the valves, how could you do that with the cam removed? :busted:

Download a manual and read it. Also search the forum for valve clearances, there were some posts about measuring everything with the engine in place.

ok will do

all valves check out except for 1 intake valve which is .18. Also when going by the manual and getting it TDC to check the clearance the cams were on the valves which made it impossible to check. So we rolled it over to where the cams were not touching the valves, to get our clearance. Also still have little compression.

Also what position should the cams be when it is at TDC

The valve that is at .18 has too much clearance. This may be the cause of your trouble, as this is usually due to carbon holding the valve off its seat, or to the valve being bent.

The cam lobes, viewed from the right of the engine, should be at 10:00 and 2:00 o'clock. The timing marks should align with the cam cover gasket surface on the head, as shown in the manual.

i can't find any pics of it in the manual that i downloaded

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