which timing is this (on a 400)

it should be WR, i rode it for a few 1.000 kms, decided to go back to YZ, counted the pins from mark to mark, and there seem to be 14

WR should have 13, YZ should have 12

did I ride "extra WR timing" or what


I dont even count the pins, just look and see if they are lined up along the head.

I did the same and probably fu::ed up


In the picture you posted there are only 13 pins between the timing marks, and the exhaust appears to be advanced, assuming the reference marks for the intake cam are alinged flat with the surface at TDC. This would imply WR timing,

This is why a lot of us use a degree wheel. :cry:

i also counted the inner pin above the mark (on the exhaust cam), so it summed up to 14

what disturbed me was the picture of WR timing, showing that above the marks, there should be outer chain pins

low q pic

looks like WR timing to me.

I would agree that it looks like WR timing to me. However, I would ask how you positioned the crank in that picture. If you had the timing mark lined up on the flywheel and your cams look like that, I would say something is amiss. I think I remember doing my 400 and the intake was even with the head, and the exhaust was the one to move. Again, though, the lobes tell a more accurate story...

the timing mark on the crank was as I remember slightly tilted(due to cam positios i guess to right)

when first doing WR to YZ, power increase in mid was felt (and a bit loss in low end)

than i moved it back to WR, and now again decided that YZ is to use

power doesnt seem to come as it did at previous YZ timing...4-th gear mid revs, punch the throttle and pull a strong wheelie, almost no go

chain should not be stretched, few months old

ill do another checkup strip and take pic of current timing

thnx all



might have made a mess becouse I removed both cams, when setting timing (and maybe misalined the intake)

it's worth noting that the TDC mark may not be 100% accurate.

Use a piston stop and degree wheel to confirm it's correct. Sice you are getting the degree wheel out you might as well put a dial indicator on the bucket and check the cam timing properly. These are the figures I came up with when I measured mine (this is a 426, which is probably slightly different to a 400).

Inlet 14-54 (open-close), 110 Deg lobe centre, 248deg@40thou

Ex (WR) 68-9 (open-close), 119.5 deg lobe centre, 257deg@40 thou

Ex (YZ) 50-27 (open-close), 101 deg lobe centre

Either the cam timing is off or you don't have the crank positioned correctly.


Looks like WR timing to me. If you were at 14 pins between 12:00 marks your bike wouldn't start and sure as hell wouldn't run. I've tried. I've also noticed that the 9:00 and 3:00 marks do not line up exactly with the head (as per the manual picutre) when at TDC with either YZ or WR timing. Hope this helps.

your answers could be a bit contadictory for me, so I opended bike again (should be YZ timed now) to try clearing it up

on the picture, the flywheel can be clearly spotted at the right mark

punch mark on inlet cam levels the head surface

punch mark on exhaust cam is slightly tilted clockwise, 1 toth, as YZ timig demands

number of pins between the upper punch marks is now 13, why 13?


sth must be a miss, could even be, that the bike doesnt perform as already once YZ timed, because of the air box cover reinstalled due to cold, rainy and muddy conditions

Looking at your BIG PICTURE, It looks like YZ timing to me. This is of course assuming that the "I" in "HI" is viewable in the timing hole which indicated TDC. If it's not, I would say that the timing chain moved off of the crank and although you have 12 pins between 12:00 timing marks you are not timed properly.

If the bike starts and runs with your timing as set in picture then you should be properly timed.

yes, the "I" part of the "HI" is positioned on the center line, marked on the hole

the bike starts and runs OK that way, although I feel the power coming out very soon

for example, 2nd gear low rpm steep climbing in soft grassy soil with no bumps, lifts the front wheel off the ground like it was helium pumped baloon

second thing, when speeding on macadams, high rpms dont give that hit, as YZ timing should, just revs high in slow motion

well, restricted air flow (air box cover) might affect the highs

just one more thing, starting to count the pins above the notch and finishing above the other still I count them 13, where do I go wrong

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