I changed the oil and filter the other day. The manual (as supplied from here) says to remove the camshaft end cover, then drain oil etc etc etc. Later it says refit the cam cover. You dont seem to need to do anything else apart remove and refit. My question is why?

The only reason I can think of is to relieve a vacuum that might build up at the top end that would prevent oil draining properly.

In the end I undid the bolts but couldnt get the cover off and as I couldnt find my rubber mallet to whack it with I decided to just put the bolts back in and worry about it next time (perhaps the vacuum was holding the cover on as it was stuck tight).

Which manual is that? I'm not at home to check, but I am pretty sure that both Haynes and the factory manual say to drain the sump (LH side of crankcase) and the oil tank (on front frame tube), but say nothing about the cam cover. The camchain comes up from the crankcase in a big wide hole, so there's no possibility of a vacuum in there.

As long as you have drained from two places (three if you count the filter housing) you should be fine. And cam covers do seem to get stuck on very tight. That's probably a good thing in terms of oil leaks etc.

(Sorry, read your post again. You mean the manual you got from this site? What page? I think there might be a misunderstanding here.)

__________________
XT660R (2006)
XT600E (1994)
Triumph Trident 750 (1992)
My blog: http://goingfastgettingnowhere.blogspot.com/

Which manual XTX, XTR, XTZ & what page?

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Mods that I have done to my XTX's

My 04 XTX
Stage 1 & 2 DNA filters / Kev fuel mod / snorkel mod / Drilled air box mod / Engine breather mod / Fork Spacer mod / 15w fork oil /
[
My 07 XTX
Raptor 700 cylinder 102mm / Modified Crank Case to take a 105mm Raptor Cylinder / 11:1 102mm JE Raptor piston / Stage 1 Raptor Hot Cam / Ported head / Colder Spark Plug / +2mm Throttle body / DNA stage 1 & 2 filters / Modified Air Box / Snorkel removed / Worry Brothers stage 2 filter cover / 6mm & 8mm Bolts Replaced with Titanium Bolts / Recovered seat in Black / O2 Eliminator /

My 09 XTX
59HP at the rear wheel / Stage 2 Raptor Hot Cam / DNA stage 3 Air Box / Carbon Can Exhausts / Modified Exhaust Link Pipes / PCIII With Custom Fuel Map / Wideband Commander O2 Data logger / LCD100 Dyno Jet display & fuel adjuster / 2500 OHM HT lead instead of a 10K OHM XT lead / Extra Coolant Cooler / Protaper Fat Bars / Tail Tidy With LED Tail Light / OKE Protection Knobs / LED indicators / AIS blocked / Modified rear sprocket rubbers / Rear Foot Pegs removed / 09 ECU With 02 Sensor Changed To A 06 ECU / Complete wiring harnes Changed from 09 to 04 / Home made LED resistor flasher / Hole drilled in the fuel tank filler neck to allow quicker filling / Modified Bar End Weights / Progressive front fork springs, 15W fork oil, forks lowered 25mm, used XTR rear links lowering the rear 20mm, rear spring one click stiffer / Changed front & rear guards from blue to black / 47T rear sprocket / Speedo Healer V4.0 / Kev throttle cam mod / Throttle grip mod / The new 2010 O2 sensor mod is out, works a treat, The new 2012 O2 Controller is out, PM me for details

Now ride a 2018 MT09SP ABS + TCS

My KTM 990 SMR Mod book. http://www.ktmsmt.com/viewtopic.php?f=13&t=4946

i found it.it's at page 3-24 of factory manual (xt660x-xt660r).PERIODIC CHECKS & ADJUSTMENTS-CHANGING ENGINE OIL.

Could that be to let air inside the engine to gain a better oil flow from the engine drain? As when you drain the oil tank and remove the filler plug you get a better flow.

Yes page 3-24 of the manual that I got a PDF of when I joined up on here. It's a 2010 XTR.

I drained the engine, tank and filter. Put a new filter in - i don't understand the yamaha service schedule of a new oil filter every other oil change though. Mine will be changed with the oil.

There was no washer on the engine drain plug either and it didn't look like it needed one anyway.

It all seems fine after a 400 mile trip yesterday.


Sent from my iPhone with a smile

I owe you an apology Austin. You are right and, in fact, I remember being a bit puzzled when I first read that myself. The Haynes manual makes no mention of it. If the two disagree, I would tend to believe the factory manual, but in this case not. I reckon it must be a way of preventing a vacuum in the cam cover, in the same way that it recommends removing the oil filler cap. I haven't done this on any other bike and I think I will be ignoring it with this one.

__________________
XT660R (2006)
XT600E (1994)
Triumph Trident 750 (1992)
My blog: http://goingfastgettingnowhere.blogspot.com/

No idea, beats me to why they would want you to do that.

__________________
Click here to join the XT Supporter's scheme

Mods that I have done to my XTX's

My 04 XTX
Stage 1 & 2 DNA filters / Kev fuel mod / snorkel mod / Drilled air box mod / Engine breather mod / Fork Spacer mod / 15w fork oil /
[
My 07 XTX
Raptor 700 cylinder 102mm / Modified Crank Case to take a 105mm Raptor Cylinder / 11:1 102mm JE Raptor piston / Stage 1 Raptor Hot Cam / Ported head / Colder Spark Plug / +2mm Throttle body / DNA stage 1 & 2 filters / Modified Air Box / Snorkel removed / Worry Brothers stage 2 filter cover / 6mm & 8mm Bolts Replaced with Titanium Bolts / Recovered seat in Black / O2 Eliminator /

My 09 XTX
59HP at the rear wheel / Stage 2 Raptor Hot Cam / DNA stage 3 Air Box / Carbon Can Exhausts / Modified Exhaust Link Pipes / PCIII With Custom Fuel Map / Wideband Commander O2 Data logger / LCD100 Dyno Jet display & fuel adjuster / 2500 OHM HT lead instead of a 10K OHM XT lead / Extra Coolant Cooler / Protaper Fat Bars / Tail Tidy With LED Tail Light / OKE Protection Knobs / LED indicators / AIS blocked / Modified rear sprocket rubbers / Rear Foot Pegs removed / 09 ECU With 02 Sensor Changed To A 06 ECU / Complete wiring harnes Changed from 09 to 04 / Home made LED resistor flasher / Hole drilled in the fuel tank filler neck to allow quicker filling / Modified Bar End Weights / Progressive front fork springs, 15W fork oil, forks lowered 25mm, used XTR rear links lowering the rear 20mm, rear spring one click stiffer / Changed front & rear guards from blue to black / 47T rear sprocket / Speedo Healer V4.0 / Kev throttle cam mod / Throttle grip mod / The new 2010 O2 sensor mod is out, works a treat, The new 2012 O2 Controller is out, PM me for details

Now ride a 2018 MT09SP ABS + TCS

My KTM 990 SMR Mod book. http://www.ktmsmt.com/viewtopic.php?f=13&t=4946