Page 1 of 2
castrol GTX obsolete, now what ?
Posted: Sun Aug 28, 2011 9:57 pm
Author: zince
Hi
I have been using Castrol GTX 20/50 mineral but now find you can't get this ( other than synthetic or semi ) or Duckams 20-50 either which has also gone EOL . I know Synthetics give you clutch slip , so what does everyone use or recommend now.
Please help as I have been everywhere for 20/50 GTX but to no avail !
Cheers
Vince
Posted: Sun Aug 28, 2011 9:58 pm
Author: hillbilly
try asda or tesco.

Posted: Sun Aug 28, 2011 10:00 pm
Author: Al
Posted: Sun Aug 28, 2011 10:02 pm
Author: z1000puddin
Asda still sell Gastrol GTX 10W40
Bought some yesterday
stu
Posted: Mon Aug 29, 2011 7:58 am
Author: MaineKZ
You could always try a motor oil that's designed to be used in a motorcycle engine!
There's been a ton of threads about oils on the forum - worth a quick search.
Most of the discussions turns on the fact that you need an oil which can stand the rigours of lubricating a gearbox and the older oils, designed primarily for car engines, are not as good at that as the dedicated motorcycle oils.
Also, in my experience, semi synthetics do not cause clutch slip in the standard Zed engine.
I'm currently using Silkolene 10/40 Super 4. Sensibly priced motorcycle semi-synthetic.
Posted: Mon Aug 29, 2011 8:09 am
Author: Big Fluff
Nothing wrong with Mobil-1 4T.
Dealers have been using this for years, admittedly in new bikes, but the base requirements are exactly the same.
I have been using it for ages. I run the ZRX1100 and the Silver Saxon Turbo on it and I haven't had any problems whatsoever, which is not surprising at all considering that the oil was actually designed for wet clutch and combined gearbox engines!, just like MaineKZ says !
Will
Posted: Tue Aug 30, 2011 9:15 pm
Author: zince
Hi and many thanks for all the input .... I have also read some more reviews from others and now feel I can make a better informed decision .
I am going for the Silkolene Super 4 in 20w50 which I know I can also use on other bikes I have too , so may be worth buying a 20L tin .
Thanks for the hint about specific bike oils for wet clutches , guess this is obvious really but earlier posts had suggested GTX or Duckhams was adequate , so I had perhaps ignored the obvious...!! ..
I will post any issues but hope the clutches remain in tact and I can spend my weekends doing more productive things rather than oil exploration :-) !
Cheers
Vince
Posted: Tue Aug 30, 2011 9:24 pm
Author: Pigford
zince wrote:I will post any issues but hope the clutches remain in tact and I can spend my weekends doing more productive things rather than oil exploration :-) !
Cheers
Vince
On the contrary, the oil is the "life blood" of the motor - so your time has NOT been wasted
Just make sure you change it regularly - every year minimum - as most owners do much less than 2k

Old oil contains acids that don't do motors much good, so do your oil change end of season, before it goes to bed for winter

Posted: Tue Sep 06, 2011 5:06 pm
Author: Magnum1
Semi synthetics smell different.
Rod
Posted: Tue Sep 06, 2011 6:34 pm
Author: Rich
go a bit faster then you won't notice what it smells like

Posted: Tue Sep 06, 2011 7:52 pm
Author: KeithZ1R
Change it every 1000 miles and you can use Mazola

Posted: Wed Sep 07, 2011 6:19 am
Author: pertonpc
I would agree with Chris Maine here - Have used a motorcycle semi synthetic on two zed engines with no problems so far.
e.g. Castrol GPS or Motul. Both were 10/40
From Mark
Posted: Wed Sep 07, 2011 12:47 pm
Author: HowieD
I always used Mobile 1 in mine and will again once it's re-run in.
Posted: Sun Sep 11, 2011 9:21 pm
Author: zince
Hi All
Pleased to advise semi synthetic Silkolene super 4 works a treat ...No clutch slip so far , bike runs a treat and seems smoother .. tried it first in the Z1B with no issues and have now put it in my 72 with no problems in either .
I have stocked up and will be using this in all the z's with regular changes...
Thanks for all the comments
Cheers
Vince
Posted: Mon Sep 12, 2011 6:38 pm
Author: Pigford
IMPORTANT NOTE:
Its not whether its
Synthetic or not - although there are some exceptions
It more crutial to choose an oil that is intended for bike wet clutches
I usually run AMSOIL fully Synthetic mineral oil in me Zeds -
this is as recommended & used by DEBBENS - say no more.
http://www.amsoil.com/storefront/mcf.aspx
Amsoil is purpose designed for use in ROLLER BEARING CRANK motors, with a very high SHEAR RESISTANCE as in engine/gearbox combined engines - ie: motorcycles.