SV oil: fully or semi synthetic?

Want to service my K5 with 4k miles before putting it back on the road. I have been offered fuchs silkolene super 4 10w 40 semi synthetic as part of a service kit. Also been offered castrol power 1 10w 40 fully senthetic. Which is better? I heard fully synthetic can cause the clutch to slip. Both meet jap requirements. Thanks.

[MJC-DEV]

Misinformation I afraid, certain (non-JAP approved) brands may affect the clutch but not Fully Synthetic as an oil type. I use Halfords Fully Synthetic Motorbike oil for example.

[Spanner Man]

Good morning all.


At the risk of starting the .org 'semi or fully great oil debate' (Which usually starts an argument). I'd go with the fully synthetic.

I've used Castrol since God was a boy. My own 900 Divvy has been on fully synth Castrol since nearly new. It's still on it's original clutch at 172k. Ok, it slips a bit now if I welly it, but after that mileage it's got every right to methinks.


Cheers.

[NTECUK]

Semi halffords motor cycle oil :P

I use semi on the road SV and full on the track SV

I've used both. currently on fully-snyth as I got a deal. As long as its bike oil then its ok. Car oil may have additives which cause your clutch to slip like a bast@rd.

[NedSVS]

This is all very debateable. I run semi synthetic in known motorcycle brands, such as Fuchs or Motul. The SV is not that highly stressed and doesn't rev as hard as a IL4, so personally I'd save the extra pennies. It's much more important you change it regularly and, of course, keep it topped up. I've racked up 40 odd thousand miles (including some track days) on my 2001 model using semi, with no problems - doesn't even require a top up between service intervals.

[dizzyblonde]

.....or you could just read the sticky thread at the top of the tweeaking section

http://forums.sv650.org/showthread.php?t=125457

Originally Posted by Spanner Man

Good morning all.


At the risk of starting the .org 'semi or fully great oil debate' (Which usually starts an argument). I'd go with the fully synthetic.

I've used Castrol since God was a boy. My own 900 Divvy has been on fully synth Castrol since nearly new. It's still on it's original clutch at 172k. Ok, it slips a bit now if I welly it, but after that mileage it's got every right to methinks.


Cheers.

172k is some mileage to get out of a bike engine isn't it?

[Spanner Man]

Originally Posted by NedSVS

This is all very debateable.

Is this the start of a 5 minute argument, or the full half an hour? (Monty Python).

Originally Posted by aaron020873

172k is some mileage to get out of a bike engine isn't it?

It certainly isn't bad going eh. It rattles a touch when starting from cold, but once warm it runs pretty smoothly.
It's my mate's old despatch bike. It's been carefully ridden, & extremely well maintained. It had 9k on it when he bought it, & has been on fully synthetic Castrol since then. The only work the engine's had was a cam chain & tensioner at around 130k.
Mind you, we managed to get his previous two XJ900F's to 200k, & 215k respectively. Now that was high mileage! Both were still on the original clutches, & the 215k one hadn't had a cam chain either.
Both were run on fully synthetic Castrol.

Obviously a despatch bike, that spends a lot of time on the motorway, & only does one cold start per day, is going to have an easier time than a commuter bike, that is often used for short journeys, & may not get fully warmed up every time the engine is started.

The problem when assessing an oil's performance, is that any shortcomings that come from using a lesser oil, will not be apparent for many thousands of miles, & as a lot of people change their bikes regularly, & don't do that many miles on each bike, engine longevity isn't really an issue for most owners.
However, as the difference between fully synthetic, & semi synthetic amounts to only around £6 per oil change on an SV. I think the extra is worth paying.

Lastly, all the bikes that I have serviced regularly over the years, that have done 'telephone number' mileage (over 150k). Have all been run on fully synthetic.


Cheers.