Hi - Just finishing up a restoration of a 1972 L2G Yamaha 2 stroke 100. I am going to replace the autolube oil and gearbox oil. I have the manual and it says #30 detergent oil for the gearbox, and SAE10W/30 for the autolube/fuel. I'm nowhere near an expert on these but given the bike is 50 years old, I guess there has been changes in oils since then, and what these bikes should run on nowadays and how critical it is.

I am thinking for the gearcase (noting wet clutch) either;
~ MOTUL Transoil SAE10w-30 transmission fluid, or
~ SHELL Rotella T4 SAE15w-40 engine oil

For the autolube I guess just any two stroke oil, like MOTUL 100 Motomix 2 stroke oil.

Sorry if this is a basic question, just wanting to get it right after the hours Ive put into it. Any advice or help appreciated... Thanks

I have and still do use both of your mentioned oils along with the Yamalube Trans-Oil Plus for the transmission/gear box. For the 2t injection pump I like to use the Yamalube 2S injection oil

I usually keep it simple and use Yamalube 2S for injection and Yamalube 10w40 for the trans in these old enduros.

But really anything rated for autolube injection should fine along with any JASO MA rated engine oil in the 10w30-10w40 range.

Motul 510 or 710 and BelRay SI-7 are good autolube options. I've used Maxima MTL trans oil in 80wt too.

Rotella T4 15w40 is a fine choice for the gearbox. Ive run it for tens of thousands of miles in a bunch of bikes.

Damn near any oil works in the injection system. I use tcw3 pennzoil. Have used super tech and maxima super m injector. As far as I can tell the only requirement for injection oil is readiness to flow at low temps. As long as it's not too thick to draw through and properly feed the pump it will be fine.

gearbox:
Bel-Ray gear saver
regular motor oils have additives that help clutch slip-not good

autolube:
Bel-Ray Si-7
made for injection systems

yes 2 stroke oils have come along way from 60 years ago-probably 20x better for lubing/scuff/oxidation/smoke/ash
One thing that has not changed is amount needed to seal rings-it is viscosity dependent-you need not worry on this bike


cliff

BlindMullet - welcome!

L2G is not a model many of us have seen...  I sure haven't. 

Pretty sure you have the manual recommendations mixed up...  not that it matters too much since you understand the "wet clutch" requirements for the gearbox oil.  

Speaking of gearbox oils, I find that the lighter weight special gearbox oils work very well if you don't mind spending the money.  Note the Yamaha recommended change interval is short...  motor oil does break down under high pressure gear loads, you can probably go a lot longer between changes safely with special gear oil. 

Another thing to keep in mind since I'm guessing you're from a "two stroke friendly" country is old air cooled vs modern water cooled engines....  The old Yamaha is air cooled and was designed to use a mineral oil  in the autolube at fairly "rich" ratios.  Modern water cooled engines may have different lubrication needs.  So I'd check and see what people are using in your country in small air cooled machines...  I'd tend towards a quality and readily available mineral-based two stroke oil rather than one of the "modern" synthetics that may not work as well in the more demanding/different air cooled environment.  ...I mentioned readily available because especially if you choose a synthetic "boutique oil", it's not generally a good idea to switch brands and types of "special oil" without flushing the autolube system first. 

The above said, modern oils are much better so pretty much whatever two stroke oil you choose for the autolube is going to be much better than what was available in 1972. 

Thanks all for the info so far, very helpful and good to know what others are using/recommend.

So looks like either the Belray75w, Yamalube 10w/40 or the Motul 10w/30 for the gearbox. And the Belray Si7, Yamalube 2s or Motul 100 for the autolube.

The manual threw me a little with it specifying an SAE10W/30 for the autolube, but apparantly this seemed fairly common back then? Will also make sure I flush all the old oil out when I change.

Thanks again – appreciate any further info anyone has. Tried to upload pic of bike for anyones interest but couldnt get it to work...

Greetings from Tennessee USA  
 We would like to see your bike you have to use a third party to post pictures ie imgur, google photos etc 

Possibly a mistake in the manual, but as I alluded to, the 10w30 spec is likely recommended for the transmission. 

Straight 30 weight motor oil would be correct for the autolube if Yamalube or other suitable injection oil was not available...  back in 72 it was easy to find single weight motor oils everywhere, detergent and non-detergent.  Today it seems the opposite, pretty much everything is multigrade.