TOPIC:

Hello All,

After a complete rebuild on my MKII, I now have about 1200 miles on it. I would like to switch over to synthetic oil but I don't want to switch before the engine is completely broken in.

I'm currently due for an oil change so I was wondering, when is it safe to make the switch? Any recommendations as to brand of oil? I've never run synthetic in anything but it sure sounds like it works well.

Thanks

dunno about this, but the small block marine motors I built, I'd run 500 miles or so, then switch. I'm guessing its ready.

You can switch anytime, you can run syn from the start. It's a myth that engines won't break in using synthetic oil.

Any other opinions on this? My bike will hopefully be ready to go soon and I'll have to think about changing the oil...

I believe you can put synthetic in right away. Many new cars come with it in the crankcase from day-1. Ed

I recently added "Motul5100 10W50" to the Z1R... and was pleasantly surprised by the difference it made to the overall running and smoothness of the gear box.

It ready. Break-in is personal preference. I perfer 500 miles on standard. Then switch to synthetic.

As provided to me, ~ 1500 miles so you're good.

There's a lot of into out there stating that the synthetic won't allow a proper break in...maybe that has since been proven wrong. I was still under that impression, but I think I'm safe now either way. I think I'll go with the synthetic now then.

Any opinions on brands? Do they make synthetic oil "specially formulated for high revving motorcycle engines" or anything like that?

Yes, there are synthetic oils that meet the JASO-MA standard for motorcycles with wet clutches. Make sure whatever oil you buy states on the container that it meets that standard. Here's what I have been using for the past 5 years and I highly recommend it. It is formulated specifically for bikes like ours.

www.mobiloil.com/USA-English/MotorOil/Oi...acing_4T_10W-40.aspx

I'm with Ed on this one...

Designed for wet clutch systems...

Awesome, thanks for the info. I was wondering about the clutch. I used Slick 50 when it first came out and it ruined my clutch....wasn't made for wet clutches back then.

Mobile 1 is a very well know synthetic oil...I'd be pretty comfortable using that. I didn't realize they made a specific motorcycle oil so that's great.

bountyhunter wrote: You can switch anytime, you can run syn from the start. It's a myth that engines won't break in using synthetic oil.

Is this from personal experience? My own experience from rebuilding engines is I have never managed to get the rings to seat using synthetic oils. I end up taking the top end apart re-honing the cylinders then reassemble and break in again with conventional oils. After about doing that 3 times on 3 different engines I no longer break in using synthetic oils. I have never had a problkem breaking in rings with conventional oils.
To answer the OP's original question, yes you can switch at 1200 miles. I usually wait until I have 1000 miles on a fresh engine then switch if I want to.

Just make sure you have really good gaskets!

I'm wondering if it depends on the type of synthetic oil you use for break in? Maybe the type available when it was relatively new was the extra slick type that would make our clutches slip...that seems like it would also prevent proper break in. Maybe the motorcycle specific oils with the proper friction properties would be OK for break in?

It seems the sentiment is growing that synthetic is OK for break in but there are still lots of opinions out there for both sides. I think I'm good since I have so many miles on mine anyway but I'd probably stick with conventional for break in just to be safe.

Also thinking new vehicles that use synthetic from the start are probably built with specific clearances and are somehow broken in already? It seems that certain race engines don't require break in...not sure what the difference is on those? They're built right at the track and run wide open immediately.

Well as many times as I change the oil after rebuilding a motor it would be really expensive/waste of money to use synthetic.
I change it after 30 minutes of running ,then again at 500 miles .
Then buy the time its between another 1000-1500 miles on the fresh oil its safe for synthetic in my book.
Yeah Im a little nuts about it but when I sold my 1327 last year I threw in a couple a couple of old motors 1 was an 1170 I put together 20 years ago and road the wheels off of really hard for several years before moth balling them ,the other was the old 1197 out of my z1.
Last I heard both motors looked basically brand new inside and all he did was throw head gaskets and valve springs in them since he was in there anyway and both motors are in running bikes being hammered at topeka last I heard.

Mobile 1 10W40 4T motorcycle is good because AutoZone has it in stock. The very best synthetic motorcycle oil I've found is Redline 10W40, but it is not easy to find and it costs more. The Redline oil gives the best shifting and it does not burn off when used in very hot conditions at high speeds.

wireman wrote: Well as many times as I change the oil after rebuilding a motor it would be really expensive/waste of money to use synthetic.
I change it after 30 minutes of running ,then again at 500 miles .
Then buy the time its between another 1000-1500 miles on the fresh oil its safe for synthetic in my book.
Yeah Im a little nuts about it but when I sold my 1327 last year I threw in a couple a couple of old motors 1 was an 1170 I put together 20 years ago and road the wheels off of really hard for several years before moth balling them ,the other was the old 1197 out of my z1.
Last I heard both motors looked basically brand new inside and all he did was throw head gaskets and valve springs in them since he was in there anyway and both motors are in running bikes being hammered at topeka last I heard.

Good point...I hadn't thought of that. I changed my oil at 100 miles and again around 300 miles. That would really add up $$$

Mobil 1 4T is without doubt a premier oil, some would say the absolute best. However, it is also shockingly expensive and often hard to find. Some will argue that diesel-specific oils have everything these old KZ engines need, and nothing that will do harm. Shell Rotella T is often near the top of that list and can be had for a fraction of the price of Mobil 1 4T.

These guys were making synthetic motorcycle oil long before anybody else thought it was cool