Oil Change - Terminal Clutch Slip Within 30 Mins

[Krikkit]

Assuming the grade you put in was OK per the service manual I'd be on to the manufacturer to let them know. Wouldn't expect a refund mind.

As noted you can probably clean the clutch up if they aren't terminally worn now, but if it was slipping until you couldn't move it's probably worn the friction material right off, or at least glazed it to buggery.

[mygoldfishbowl]

V8RX7 said:

unident said:

Benni said:

If the bike has a wet clutch, I would only use mineral oil, not semi-synthetic or full synthetic,

as synthetic oils lead to clutch slip.

Really?

I knew this would come up and I've heard similar, yet all the modern oils for modern bikes are semi / full synth

I do all my own work - always have, I've been using a cheap semi oil in my bikes without any issue for years - I change it every 200-300 miles (competition KTM but not used in anger) it only takes 1.2L

Yet the first time I've used fully syth bike oil my clutch has failed spectacularly and everyone is telling Benni he's wrong yet here I am demonstrating in some cases at least, he's right !

With all due respect you're not demonstrating anything. You changed your oil - your clutch failed, you have no evidence the two incidents are linked.

[Steve Bass]

Friction modifiers in the errant oil will probably have impregnated the clutch material. if so, it'll never come right so little other to do than replace the cluch pack anew and use the correct grade oil from a reputable manufacturer.

Worse things happen at sea...

[LimSlip]

Why the huge reluctance to mention the specific oil that was used?

[thatdude]

V8RX7 said:

I knew this would come up and I've heard similar, yet all the modern oils for modern bikes are semi / full synth

I do all my own work - always have, I've been using a cheap semi oil in my bikes without any issue for years - I change it every 200-300 miles (competition KTM but not used in anger) it only takes 1.2L

Yet the first time I've used fully syth bike oil my clutch has failed spectacularly and everyone is telling Benni he's wrong yet here I am demonstrating in some cases at least, he's right !

Ok, since we're going on anecdotal evidence: I used to have a suzuki SV650s, bought it at 18,400 miles, ran it until about 77,000 miles. I almost always filled it exclusively on semi-synthetic.

One time, just because I could, I filled with fully synthetic (Castrol something-or-another, 10w40, motorcycle specific meeting JASO-MA standards) having read that it could help lower engine temperature / be more stable when running hot. This was around 57,000 miles or so. I was happy enough to do it again at the next fill (61,000 ish miles) but went back to semi-synthetic at 65,000 miles because it made no real diffrences and the semi synthetic was a bit cheaper.

No issues with the clutch. Engine did use a bit more oil though, maybe 600 mL between services (4000 miles) instead of 400 mL.

So that makes it 1-1 so far on "does fully synthetic oil kill my clutch?"

Let's face it, the clutch on a vehicle is a wear item. That;s it's very nature; there is slip, there is friction, and where there are these two tings there is wear. You mention you use the bike for off-road work, I suspect there is a fair amount of abuse the bike is taking so it stands to reason the clutch is also receiving it's fair share.

By all means inspect everything, it could be another component causing issues. I very highly much doubt the change in oil specification has anything to do with it.

Edited by thatdude on Monday 29th June 10:19

[Jazzy Jag]

Oils designed for car engines have friction inhibiting additives.

Bike oils don't because of their wet clutch

If you used a car engine oil, that could account for the problem.

Time for a clutch strip and clean at the least and fingers crossed.

[thatdude]

V8RX7 said:

As mentioned I do it pretty much monthly - the only change was to a new oil and it slipped immediately, the old oil had done less than 200 miles

So what will you do from here? Will you inspect the clutch itself? How about going back to the previous oil specification?

[archie456]

I reckon your clutch plates were virtually worn out, but masked by the old thinner oil.

The new oil was thick/slippy enough to highlight the weakness and then it wore out completely.

I'll pm you my address so you can send the prize

[Steve Bass]

archie456 said:

I reckon your clutch plates were virtually worn out, but masked by the old thinner oil.

The new oil was thick/slippy enough to highlight the weakness and then it wore out completely.

I'll pm you my address so you can send the prize

Not a bad synopsis but..

The alternative is that by saying he uses "Cheap" oil, maybe some mazola found its way in there. Used of course, from a month frying fies and fish in MaccyDee's.

I claim my proze.

[unident]

V8RX7 said:

unident said:

Benni said:

If the bike has a wet clutch, I would only use mineral oil, not semi-synthetic or full synthetic,

as synthetic oils lead to clutch slip.

Really?

I knew this would come up and I've heard similar, yet all the modern oils for modern bikes are semi / full synth

I do all my own work - always have, I've been using a cheap semi oil in my bikes without any issue for years - I change it every 200-300 miles (competition KTM but not used in anger) it only takes 1.2L

Yet the first time I've used fully syth bike oil my clutch has failed spectacularly and everyone is telling Benni he's wrong yet here I am demonstrating in some cases at least, he's right !

The reason I said “really?” Was more out of incredulity at the comment, rather than asking a question. Pretty much every oil you buy is semi or fully synthetic now. My racebikes have always run on fully synthetic without any hint of clutch slip due to oil.

What grade of oil is recommended for your bike? What’s this mysterious oil that you used that you won’t share the details of? Given the number of times it’s been asked for and not given, that makes me wonder about this.

You’ve even admitted to using car oil for the last two years in the bike, ever thought that could be the reason?

V8RX7 said:

Yes and for two years I've been using car oil !

Positive - it gets changed monthly

[V8RX7]

I've already contacted the company and simply don't want to name them until they reply

I love the usual PH conspiracy theories

It really is as simple as:

Using semi syth car oil for 2 years, changing monthly / 200 miles ish without issue - no point paying for expensive oils that last 6k when I change it so regularly and it only holds 1.2L

Changed to bike specific fully syth and the clutch immediately slipped - hence hardly a leap to suspect the new oil is far slippier than the old oil !

[unident]

V8RX7 said:

I've already contacted the company and simply don't want to name them until they reply

I love the usual PH conspiracy theories

It really is as simple as:

Using semi syth car oil for 2 years, changing monthly / 200 miles ish without issue - no point paying for expensive oils that last 6k when I change it so regularly and it only holds 1.2L

Changed to bike specific fully syth and the clutch immediately slipped - hence hardly a leap to suspect the new oil is far slippier than the old oil !

Or the car oil has done loads of damage and the new specific oil has highlighted the damage. It’s a definite possibility and one that you’d struggle to disprove

[NS400R]

Car oil is your cause. A couple of hours labour and a new set of friction plates. The friction modifier builds up over time but never seems to wash out of the plates. Just buy bike oil from now on and put it down to experience.

I made the same mistake in the past. My friction plates were at new spec but contaminated.

[airsafari87]

V8RX7 said:

I've already contacted the company and simply don't want to name them until they reply

I love the usual PH conspiracy theories

It really is as simple as:

Using semi syth car oil for 2 years, changing monthly / 200 miles ish without issue - no point paying for expensive oils that last 6k when I change it so regularly and it only holds 1.2L

Changed to bike specific fully syth and the clutch immediately slipped - hence hardly a leap to suspect the new oil is far slippier than the old oil !

Did you inform them that you had previously been using car oil?

[Jimmy Recard]

unident said:

Or the car oil has done loads of damage and the new specific oil has highlighted the damage. It’s a definite possibility and one that you’d struggle to disprove

Unfortunately this is what I think happened

[V8RX7]

unident said:

Or the car oil has done loads of damage and the new specific oil has highlighted the damage.

It’s a definite possibility and one that you’d struggle to disprove

I've just pulled the clutch - looks fine

Court is simply balance of probability A+B=C not the PH way of A2xCz-BDF could possibly = Y

I've asked on another bike forum and others have had similar experiences with synthetic oils

[Steve Bass]

V8RX7 said:

unident said:

Or the car oil has done loads of damage and the new specific oil has highlighted the damage.

It’s a definite possibility and one that you’d struggle to disprove

I've just pulled the clutch - looks fine

Court is simply balance of probability A+B=C not the PH way of A2xCz-BDF could possibly = Y

I've asked on another bike forum and others have had similar experiences with synthetic oils

But you don't use car oils for bikes... for this very reason.

And saying you use cheap oil because it doesnt stay in long is missing he point.

Cheap oil is cheap oil..... it's crap from the get go.

[CousinDupree]

You can have problems with contamination and reaction between oils. Mixing between car / bike oils is a gamble, particularly if you have a wet clutch.

I've had this problem before with an Aprilia and a few race bikes, switching bike oil brands. But then the OP seems to be all knowledgeable and dismissive...

[Lazermilk]

airsafari87 said:

V8RX7 said:

I've already contacted the company and simply don't want to name them until they reply

I love the usual PH conspiracy theories

It really is as simple as:

Using semi syth car oil for 2 years, changing monthly / 200 miles ish without issue - no point paying for expensive oils that last 6k when I change it so regularly and it only holds 1.2L

Changed to bike specific fully syth and the clutch immediately slipped - hence hardly a leap to suspect the new oil is far slippier than the old oil !

Did you inform them that you had previously been using car oil?

Doubt it...

[Steve Bass]

Lazermilk said:

airsafari87 said:

V8RX7 said:

I've already contacted the company and simply don't want to name them until they reply

I love the usual PH conspiracy theories

It really is as simple as:

Using semi syth car oil for 2 years, changing monthly / 200 miles ish without issue - no point paying for expensive oils that last 6k when I change it so regularly and it only holds 1.2L

Changed to bike specific fully syth and the clutch immediately slipped - hence hardly a leap to suspect the new oil is far slippier than the old oil !

Did you inform them that you had previously been using car oil?

Doubt it...

The truth is usually the first casualty...