Modern Vespa

What is everyone using on their tuned engines? Still SAE30 filled to the level that dribbles out of the oil screw?

I've managed to transfer to a Reed valve setup but noticed oil coming out of the clutch breather valve when I maintain high revs at a decent 80km/h

I'm thinking I might have had too much oil (filled it with the side stand), and I'm using SAE30...

Was wondering if tuned engines had any different needs because of the demands (more oil, less oil, different type of oil)?

Anyone have any thoughts?

My personal conclusion on oil is to run what the clutch manufacture tells you. I suspect your issue has nothing to do with oil type though.

Bike should be level when measuring oil. Have you changed it recently to see how much "oil" comes out and compare that to much you put in? If more comes out, then extra fluid of some sort is getting in there.

My bet is on an air leak. Have you pressure tested your engine lately?

SIP didn't provide specs for the oil to use with the clutch and I don't see any documentation online... SAE30 is the oil recommend in the Haynes manual...

There's 2 questions which are related, but different:
1. What oil are people using with their tuned engines... is there a need to use modern oils?
2. Anyone experienced oil out of the breather and had problems which where not related to having too much oil and increased pressure? Is there anything related to an increase of power and higher revs?

You mention air leaks? From where? Pressure test the cylinder?

JASO MA2 spec oil is what I use.

Oil coming out of the breather is almost always a major air leak. Clutch seal or oil sucker both very similar. Pressure test will confirm it.

Hi!

I'm using SAE30 in all my tuned engines, unless told otherwise by the provider of the clutch.

I've had 30+hp Malossi engines runing with SAE30 without any trouble.


But those engines I have CR80 clutch plates in, I use modern gear oil.



Regarding oil spitting out of the breather, it is most likely related to use of sidestand and overfilling.

Scooter need to be level when filling oil, -then it gets the right amount.

But if you have a short sidestand, with the scooter leaning alot to the side, you can/will experience spitting out of the breather.
-at least that's my experience....

Good luck!

I am using the CR80 plates and I am using a shortened sidestand (its like you know...) probably doesnt help my cause...

I will double check my oil levels and see if it helps out.

Got it...

I sealed the cases up super carefully this time with the reed valve setup, to try eliminate the oil sucker, as my last crankcase the gasket completely shifted away from the cases (not sealed by me)...

I had the same situation with my last engine, i just thought i was riding it too hard... Clutch seal? it does have the metal clutch seals, ground down to 3.5mm...

Looks like i'll have to do a leak test...

Seems like the side stand is the culprit...

The oil level now, is just a bit lower than the filler plug (probably because I've lost some old out of the clutch breather) when the bike is level...

Before I went for a test run, I leant the bike over toward the engine side for a good 3 mins before starting the engine...

Before, I would just start off and be riding a little hard quick quickly...

I still got some coming out of the breather, but it's no where near the amount before...

I'm still going to do a leak test when I get time just to make sure I don't have an oil sucker or seal leak...

How does the gearbox oil know the engine has been tuned?

Lol, it doesn't...

Bad lubrication and metal flakes in the oil will tell you...

I'm going to go with the recommendation on using modern 75w90 oil, the CR80 plates will probably need it...

Waiting to order some new oil, I managed to do a leak down test...

Using a bicycle inner tube... made a closed circuit...

Managed to isolate a small leak in the intake/Reed block... but it wasn't anything significant. Didn't isolate any problems at the crankshaft seals which is great piece of mind.

I use this silkolene light gear oil. It allows me to use slightly lighter clutch springs than I normally would and no more clutch slip.
You also don't need a bionic commando hand to pull the clutch lever in!!

I also use this clever clutch breather that Sip sell. No more oil drool from the clutch vent.

I actually just saw this breather replacement on the SIP BFA 306 video series and was considering picking it up. I'm curious how much cleaner it helps to keep the engine/wheel well?

https://www.sip-scootershop.com/en/product/ventilation-screw-oil-filler-hexagonal-sip-by-salem-speed_31116600

Unfortunately I have a tendency to ride bikes with super hard clutch actions needed. Gained pretty strong forearms already... lol Stupidly, I ride an mid 80's Honda to work everyday, and my other bike is a 70's BMW.

So thats a lighter gear oil used? Your setup is a revvy one right? and theres no slippage? thats great...

I cant imagine the stock breather being able to take the oil being spun around past 5000rpm for long periods of time and not drool out of the top... interesting you dont see more hosed breathers tuned engines

MB scooters has a similar type breather, I was planning on buying...

https://www.lambrettaspares.com/spares/vespa-spares/vespa-oil-breather-cap-stainless-steel-mb/mbp0425k.html

looks like the SIP is good with the bracket holder and filter end... will look into it

When i was using my centre stand to park, the clutch cover would always be drooling and sweating oil... after it collected a bunch of brake dust it'd be pretty grimey...

Now, I'm using the side stand now as i've taken off the centre stand and havent had the chance to reinstall it (i'm putting it off as its actually much more heavier than i remember... lol)

It seems (guessing at the moment...) that after i go for a ride and park it, the oil from the clutch collects in the cover, so when i start the bike again, it slings it straight into the breather. I'm tilting it to the right side now just before i start the bike and it seems to have helped...

But I'm definitely looking at the hose option now to keep it all clean

Same here. I didn't realize so much of the grimey oil buildup in the wheel well came from that breather. I guess its not a bad price to take a chance and see if it helps keep things cleaner.

The breather extension is a good way to keep the oil from weeping out.

Not too difficult to DIY either. You'll need 2 breathers and a bit of hose.

Take one breather and carefully remove the "cap". Only cut off the outer top cover, leave the small tube inside. This piece threads on your clutch cover as original.

Add your tubing to the modified breather on the clutch cover.

Add the 2nd breather to the top of the tubing. Just thread it in like normal.

Secure the tube and 2nd breather somewhere safe and enjoy clean engine bay!

That actually makes a lot of sense... will give it a go...
Any photos of it being attached to the bike? I was going to attach the hose together with the spaghetti that comes from the pwk...

Getting confused about this now...

I never really questioned it before and used SAE 30 for the past 4 years and found out i was using 10w40 for my gear oil changes before that...

I was looking at what SIP had to offer regarding oil and the malossi 75w90 oil popped up, i was about to order it last week (got delayed) and then i discovered the 10w40 oil...

what gives?

the 10w40 oil the same as 75w90 gear oil?

any cons to using 10w40?

The viscosity is about the same. The difference is most 10-40 engine oils have detergents and friction modifiers that don't always interact well with a wet clutch.

ND30 does both jobs perfectly well - lubes the gears and keeps the clutch corks from burning up without slipping.

Ok, so youre using the SAE30?

Seems to make sense for most vespa applications.

I'm still thinking about my CR80 clutch plates and would they need a different viscosity, without detergents?

I made up one of those about 5-6 years ago for my Lammy. It helped out big time to keep oil off of my case. I haven't tried one on any of my Vespas yet, but it sounds like a good idea. Put me down for 10 of them!

Managed to use an old breather and machine the mushroom cap off and install a 5mm I.D Hose. might put in some "flats" for the spanner to grab onto...

But this is what it looks like...