I accidentally switched to full Synthetic (Kawasaki) oil
this last change and have been using premium (fuel)
since I got the bike, have put on about 7k miles.
I mention Arizona, cause it seems I've read
that some states have different additives and
grades, I think they call the premium fuel out here
91 Octane, then we have 89 mid grade and 87 'regular' .

Kawasaki says we need to run 90 RON. Here in TX, we have the same 87, 89, and 91 choices for E10 gas. If I fill up with E10, I get the 91.

For non-ethanol, we have a 90 octane near me, which is what I usually run.

Houston is hot similar to Arizona, and i think it's a bad idea to run lower octane especially in summer. Maybe you can hear knocking, but I'm not convinced I'd hear it.

Regarding oil, why would you run anything except full synthetic? I just changed mine with Rotella T6 15W40. I think it's a good choice for hotter states. Cold states might want to go 5W40.

* Last updated by: TXZX14 on 2/25/2026 @ 1:34 PM *

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I've stuck to conventional oil the first few thousand miles on my bikes. The idea is that synthetic oil might inhibit the process of the engine wearing in. Also, I'd be changing the oil more frequently during the break in period and most synthetics are pretty expensive, Rotella is the only exception I know of. I used it for many years in my Gen1 ZX-14 and Gen2 Hayabusa. I'll probably follow the same routine with my Gen2 ZX-14 and Gen3 Hayabusa. One more reason someone might prefer to avoid synthetic oil is that it leaks easier than conventional oil.

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I'll probably follow the same routine with my Gen2 ZX-14 and Gen3 Hayabusa

I've got 11,000 mi on this bike now, you've done a lot more
oil changes on this type of bike than I,
do you find that the 2000 mi mark is about best for
a 50 50 mix of street and fast Canyon riding?

do you find that the 2000 mi mark is about best for
a 50 50 mix of street and fast Canyon riding?

Depends more on the rider than the bike. How about street and careful fast as you reasonably can canyon riding? You've had other bikes. You work into it gradually.

as for oil changes, best is fresh oil out of the bottle. Change every 2500. You'll know you're overdue if the bike misses a shift. As for expensive synthetic oils, they might shift good for long past that. I never tried them. I used a synthetic race oil once. It was incredibly smooth for 500 miles, then it was like normal oil. Hub pointed out, "race" means it's good for a race. Then you change it.

If you have 11,000 miles on the bike, that's enough to go with synthetic. I can tell you, Rotella doesn't feel any better than conventional as far as the shifting. That damn race oil was amazing. ...for 500 miles. Maybe some of the other synthetics like Amsoil are right down the middle but you'll pay for them. I just trust in clean oil I can afford to dump.

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That damn race oil was amazing. ...for 500 miles.

What were you using?

Honda. This was 18 years ago, Strat. I think it was HP4. It was very expensive but I had to try it. This was also when I believe my head cover gasket started to leak. I don't blame it on the oil, the bolts were finger tight. That first gasket we had sucked and tyhat's what I blame it on. Well anyway, if you can get your hands on some of that oil, your bike will snap right into first gear as smooth as butter and you won't feel a thing shifting through all the other gears. You hear them but you don't feel them....for a few weeks. Then it's normal oil.

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I don't blame it on the oil, the bolts were finger tight. That first gasket we had sucked and tyhat's what I blame it on. Well anyway, if you can get your hands on some of that oil, your bike will snap right into first gear as smooth as butter and you won't feel a thing shifting through all the other gears. You hear them but you don't feel them....for a few weeks. Then it's normal oil.

'Possibly' HP4 , I see that's from Honda or they endorse it,
not finding it on Amazon, my go to source for everything.
I asked to kind of get a confirmation on what the oil is or get
educated on what the oil is really about.
I see in my search that there is Valvoline racing oil but it's conventional
and very inexpensive so maybe that's not a good alt, I wonder how that
oil behaves.

I noticed this am that when I get to a signal and for whatever reason
didn't finish all my down shits, it seemed like it went into
3, 2 and 1 a lot easier than before, sometimes I'd get to 2 or 3 mph
or stopped, and almost panic cause it's not just bada bing bada bang
back down to 1st, had to roll the bike a few inches back and forth
to make it happen.
I'll have to test it some more, and especially when stopped,
I'll try to give that a test in the am.
So if it slides into gear better with full synthetic or racing oil
or synth racing oil as the case 'can' be, wouldn't this be
kinder on the dog-bones, shift forks, and other components related to
shifting.
If that's the case I think I'd prefer to chg oil at 2500 mi,
and I think guaranteed quick downshifts at a signal is
a deal-sealer for me right there.

I gather by reading this review that Mobil 1 for track use only
will gunk up cats, so not really good unless running full exhaust,
and hence the 'track use only' disclaimer on the bottles.

5.0 out of 5 stars Racing use only?
Reviewed in the United States on March 27, 2017
Verified Purchase
Love this oil. Yes i run it on the street. No i do not have cats and the 02's i get for free when they plug up. I would not recommend this oil if you have Cats or 02s. Otherwise its amazing. Holds the oil pressure during track days doesn't thin out like the 15-50 i was using. New engine looks great inside after changing the cam to a bigger one. Glad i found this oil.

Mobil 1 $64.00 (sport bikes) racing oi
1 98JA11 10W-40 Racing 4T Motorcycle Oil for Sport Bikes - 1 Quart (Pack of 6)
4.84.8 out of 5 stars (780)
100+ bought in past month
Price, product page$64.00
------------------------------
Mobil 1 TRACK USE ONLY
10W-50 Full Synthetic Racing Motor Oil - 1 Quart (Case of 6)
4.44.4 out of 5 stars (24)
Price, product page$90.01 ($0.47/fluid ounce)
----------------------
CONVENTIONAL OIL;
Valvoline VR1 Racing SAE 20W-50 $32.00 6 QTS Conventional Oil
4.84.8 out of 5 stars (4.6K)
600+ bought in past month
Price, product page$32.36 ($0.17/fluid ounce) List: $48.39List: $48.39

Summary; I guess that I need to stick with just plain synthetic if
so long as I'm having a catalytic on my bike and want
smoother shifting.

* Last updated by: Stratovarious on 3/7/2026 @ 3:37 PM *

How does this sound?

Was an A level rider sponsored by Torco oil. B racers were given a few cases. A racers backed up the truck. So going on 50yrs later, I've been mixing half and half 50w racing with other grades of oil from the cars. First oil change with 4 ZX14's since they first came out, I have yet to blowup or damage the engine when tearing open every oil filter I've changed for inspection.

All have been clean to now, super clean (book break in), showing the filter pleats spotless. I've used syn with 50yr old oil for decades with all my cars and bikes since.

The 50w shows a sweet shifting trans for a few hundred miles and signs off. So I've stopped being anal about oils to use. Mix and match is no problem on my end. Kind of shows the fallacy about oils for me.

Mao's little red book quote: "No investigation, no right to speak"

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I've been mixing half and half 50w racing with other grades of oil from the cars. First oil change with 4 ZX14's since they first came out, I have yet to blowup or damage the engine when tearing open every oil filter I've changed for inspection.

When you say mixing half 50w, with other oils, and mix and match.....
would you have been mixing up grades too or just different oils?
Racing mixed with other synthetic or conventional?
20/50 with 10/40?

The 50w shows a sweet shifting trans for a few hundred miles and signs off

...and synthetic or conventional 20/50 racing/non racing oil?
And only smooth for a few hundred miles, then just like other oils?
Summer's coming on here soon, 100 to 120+ F, am I crazy to switch
to 20/50 when the heat hits us, or is that probably
a good plan?

So I've stopped being anal about oils to use.

So; change the oil, frequently, and don't obsess with every little detail
on the oil can label? Sounds reasonable.

Mao's little red book quote: "No investigation, no right to speak"

Was that right before or after he killed off 60 million of his own.
I prefer Confucius;
''Eat cookie not fortune'' as translated by stratovarious.

Speaking on Fuel, since there are so many regional differences
in octanes, and I've read that 87 can be better for our bikes
than 91, not actually knowing who's 87 and who's 91, I put in
3 gallons of Arizona 87 yesterday as a test, to see if I can
tell the difference one way or the other.... will report back
if the engine doesn't seize.

* Last updated by: Stratovarious on 3/8/2026 @ 4:08 AM *

So if it [synthetic] slides into gear better with full synthetic or racing oil
or synth racing oil as the case 'can' be, wouldn't this be
kinder on the dog-bones, shift forks, and other components related to
shifting.

I would think so.

Summary; I guess that I need to stick with just plain synthetic if
so long as I'm having a catalytic on my bike and want
smoother shifting.

You have an O2 sensor on the stock exhaust too.

Speaking on Fuel, since there are so many regional differences
in octanes, and I've read that 87 can be better for our bikes
than 91, not actually knowing who's 87 and who's 91, I put in
3 gallons of Arizona 87 yesterday as a test, to see if I can
tell the difference one way or the other.... will report back
if the engine doesn't seize.

I've used regular which I believe is 85 octane here. This was with my Gen1. The deceleration popping was about 35% more. I couldn't feel any increase in power. The dealership advised me to ride it gently until there was enough space in the tank to dilute it with premium. Premium gasoline for sporting use here has no ethanol so that's what I'm sticking with. Also, if what was happening in the exhaust could happen in the engine, there's my other reason to go with 90 or higher octane.

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50w is straight 50 weight. I've mixed 10w40, 10w30 and no problems. That means 2qts of 50 mixed with 10w40 and topped off with 10w30. I've mixed syn with the 50w. Still crude mixed with additives mixed in the same oil.

As far as octane, 87 used in hot days will detonate, but I don't care. It's rare when I hear it. Drag bikes use 87 being it lights off faster, where higher octane moves slower. Sure, I've seen the piston dome where there is a V mark for the machining and when det occurs, it blows that V into a crater. But that was a heavy load on the throttle, a higher gear, and up a grade to cause that.

Octane booster is used in the summer. 20w50 is OK for the summer. 0w30 would be good for winter months. Most any fresh oil will shift better, but within a few hundred miles, she bangs, etc.

No oil is the same from other countries, so use the quality oils to stay safe. Heat and contamination kills the oil, so yeah, the more you change it, the longer the engine life.

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I've used regular which I believe is 85 octane here. This was with my Gen1. The deceleration popping was about 35% more.

I'll make a note of that decel popping, I haven't listened for it
yet.
Supposedly the Maverick gas stations here has
87 octane eth free, and the Texaco has 91 eth free, but Texaco
here is a price gouger on all their fuel here.

* Last updated by: Stratovarious on 3/9/2026 @ 5:01 AM *

Sure, I've seen the piston dome where there is a V mark for the machining and when det occurs, it blows that V into a crater. But that was a heavy load on the throttle, a higher gear, and up a grade to cause that.

'' 'V' into a crater'' is that as in ruined piston, or marks on piston?

Octane booster is used in the summer. 20w50 is OK for the summer.

Good, I wondered if I was on the right track on that, it gets blast furnace hot
out here in the summer.

Octane booster is used in the summer. 20w50 is OK for the summer.

so use the quality oils to stay safe.

I here that, I plan to stick with the quality oils for sure.

You have an O2 sensor on the stock exhaust too.

Right, the O2 sensor is something that doesn't enter my
thoughts, often, in fact only when I see it in print.
I guess it gets clogged from racing oils and bio fuels just
as much as the cat? Is the O2 Sensor easy to get at?