Timing Question

[BOULMAN]

I just got a 02 wr426 that is dual sported. I followed the manual in regards to lining up the timing marks, but when I do the Intake and exhaust are not lined up. I have to rotate the crank to about 11 o'clock to get them lined up like the pics. It doesn't look like the yz timing either. Any suggestions?

should I adjust the cams to line up?

thanks

jb

[MX_Ryda_192]

at 12 o clock, is one cam lined up and one not?

[BOULMAN]

No, that's why I don't think its right. If the intake was lined up and the exhaust off a tooth, I would say yz timing? They both line up, but I have to go counter clockwise about 1 "hr" to get them to line up.

The reason I am suspect is it seems to run ok, but it has a ping( vibration) when I accelarate hard after lugging the engine a little bit when I am cruising down the road.

Thanks for any input about this

jb

[Hamish]

I wouldnt ride the bike until this matter is sorted.

1st thing I'd do is verify TDC is correct. Unless you have a degree wheel and piston stop, use the long CLEAN screwdriver down the spark plug hole trick. Always leave the engine at TDC when doing timing. Sounds like you are 1 or maybe 2 teeth retarded on both cams. Only other possibility is that the chain is severly stretched. Check how far in the tensioner is. If it's much past 1/2 way you may have a chain issue.

As the timing chain stretches (normal wear and tear) , the exhaust dot will be higher above the head surface and the inlet dot will be below the head surface. (by 1/2 tooth less)

[BOULMAN]

When checking the tensioner, do you hold the tensioner with a screw driver as you unbolt is?

[Hamish]

When checking the tensioner, do you hold the tensioner with a screw driver as you unbolt is?

the easier way to do it is to remove the tensioner, then take a CLEAN screwdriver and press it in the hole where the tensioner came from until the chain is firm. Then, using a nikko pen mark the shaft of the screwdriver where it is level with the tensioner gasket surface on the barrel. You can mow sit the screwdriver beside the tensioner to see hoiw far the tensioner is extended when it's in the engine. Unfortunately, Yamaha dont give specs for a 20 link lengths of chain like other makes do, so this is the only way to guage chain stretch.

[BOULMAN]

Sounds like a plan. If the tensioner is I will have to assume the previous owner had no clue how to change the bike to yz timing.

[Hamish]

I'd be assuming that anyway. As the saying goes, if you want something done properly, do it yourself. I suggest you check your TDC, then set the cams up to YZ or WR, whatever you want, then take some pics of the cams and post it on here BEFORE you start it. Then one of us can verify that it's correct

[BOULMAN]

Well I took the bike apart and had my dad look at the timing with me. It looks like the intake cam is ok, maybe a quarter of a tooth off. The intake side lines up right with the head surface. The exhaust cam look just like the yz timing. I just needed a set of experienced eyes to look at it.

Also, checked the tension of the chain, maybe 1/3 of the throw of the tensioner is being used. ?

I'll chaulk this up to inexperience and a being a little to critical.

thanks for the input guys.

jb

[Hamish]

thats good news. It's better to be safe and ask lots of questions than lunch your engine

[Slowmotion426]

...plus it helps others who read this and were too timid to ask ... ?