old school race engine, need oil reccomendations

Status
Not open for further replies.
M

MrRPM

Joined
Aug 25, 2011
Messages
437
Location
Michigan
So I have an old ATC110 (3 wheeler, engine also found in CT110s and are based off of the 90cc horizontal engines honda used before the 110)

I have recently rebuilt the engine with a 125cc (cylinder being at its maxx) 10.5:1 piston, race cam, stiffer valve springs, 24mm race carb, DG exhaust, and pretty much replaced everything else that was worn out in anyway. (majority of engine parts)

well it was burning a little oil and was not shifting right so i took it apart after maybe 1-3 hours. the cylinder is lightly scored on the top and bottom of the cylinder (remember, its horizontal) and the piston is also very lightly scored.

Its smooth to the touch but is still visually there, im going to hone the cylinder and run it. the rings look good and everything else like the cam looks good.
This was on Honda GN-4 10w-40, probably 2-3 oil changes in this period (this engine uses no oil filter so i changed it alot during break in)
well im wondering what other oil choices are out there. specifically something that can ease my problem as much a possible and also keep my race cam with stiff valve springs protected (being a flat tappet design). I don't plan on doing long OCIs and will probably change it every few hours of ride time as it only takes 1 quart of oil.
looking for a high ZDDP oil in a 0w to 10w-40 oil

any suggestions?
 
Since this ATV has a wet clutch (shares the oil with the engine) you should use a JASO/MA rated oil to prevent any clutch slippage. If it were mine I would run Shell Rotella T in 15w40 (it is a conventional oil since you said that you were not interested in long OCs).

A 4 quart bottle is about $12 at Wally...
 
Last edited by a moderator:
yes, i am well aware of the wet clutch issue
there are 2 things about rotella that i worry about.

This engine will mainly be used In Michigan winters, used for deep snow usage. so i worry a 15w will be too thick on start up. so t6 would be a must since its a synthetic 5w-40

also, i worry that rotella does not have enough ZDDP which is around the 1100 mark (t6 anyway), but i see other (and mostly thicker) oils specifically for old school motorcycles using 1600-1700PPM. like mobil 1 v-twin. too bad its a 20w-50
maybe im just weird and have read too many articles...
 
Last edited:
My first 3-Wheeler was a 1980 ATC110. I did the same as you with the big bore kit, Super loud Bassani exhaust, bigger Cam etc.

I even had the spring loaded skate board wheels for a chain tensioner since the splines on the stock tensioner constantly strip and let the chain flop around.

I ran Pennzoil 10w40 in mine back in the 80's.

Anyway the Honds GN4 oil isn't anything special. The 15w40's would be a better choice than the Honda oil. Maxima makes a great oil but you will pay top dollar.

Edit: While this engine does not use an oil filter it does have a oil screen inside the case.
 
Last edited:
Originally Posted By: Chris142
My first 3-Wheeler was a 1980 ATC110. I did the same as you with the big bore kit, Super loud Bassani exhaust, bigger Cam etc.

I even had the spring loaded skate board wheels for a chain tensioner since the splines on the stock tensioner constantly strip and let the chain flop around.

I ran Pennzoil 10w40 in mine back in the 80's.

Anyway the Honds GN4 oil isn't anything special. The 15w40's would be a better choice than the Honda oil. Maxima makes a great oil but you will pay top dollar.

Edit: While this engine does not use an oil filter it does have a oil screen inside the case.


yea it does have a screen, but looking at the oil after the tear town there is quite a bit of metal shaving in the oil but almost nothing is stuck on the screen. it has the mesh size of a window screen.

does rotella t6 meet the JASO MA spec that the 15w40 rotella meets?
 
Amsoil 0w-40? Are you talking about their Snowmobile Oil, cause thats the only 0w-40 weight oil they have that I Know of. Do you mean Mobil 1 0w-40? Thats much Better than Any Amsoil in my opinion(IMHO? iS tHat riGht?). Amsoil has some Good 5w-40, 10w-40 oils, Their 10w-40 HIGH Zinc comes to Mind.
 
i looked into the amsoil and their SAE 10W-40 Synthetic Premium Protection Motor Oil (AMO) caught my eye, being JASO MA rated and having high anti-wear additives.

Mobil 1 4T has also caught my eye having similar add pack numbers.

Shell rotella t6 is also not forgotten.

Im not concerned about price too much, i have had this 3 wheeler since childhood and just did a full restoration on top of the engine build, so price of oil is not a place to slack on.

wanting to use a synthetic just because this 3 wheeler will mainly be a winter machine and its cold flow is just peace of mind.
 
The Amsoil Powersports 0w40 I saw tonight on the shelves was Jaso MA and would protect on cold starts a lot better than a 10w40 would. Simply due to getting the oil circulated faster in the cold.
 
Originally Posted By: Slick17601
Sounds to me like you may not have enough piston to wall clearance.


might be true, we will see what happens
i also broke it in with no load on the engine. as we were trying to get the carb and intake dialed in we ended up running the engine for quite some time before riding it. not sure if this would be a cause for any of my problems but this time around im going to try a different method.

if it burns oil again after riding it all winter then ill tear it down again. might just go back to a smaller size piston. who knows
 
Brad Penn 10w-40. Good for winter use and high in zinc. The additives package is just what you would need for that engine.
 
Status
Not open for further replies.

Similar threads

B
Racing motorcycle oils
2
Replies
23
Views
3K
Bonz
F
Valvoline 10w-40 and Rotella T4 15-w40 JASO MA / MA2
Replies
18
Views
2K
Bonz
donnyj08
Let’s Talk 5W40 4T oils - New BMW R1300GS
2 3 4
Replies
75
Views
2K
donnyj08
P
Engine Oil for roller cam Pontiac 461?
Replies
13
Views
302
kschachn
M
Help me choose a racing oil
2
Replies
30
Views
7K
thetricky
Back
Top Bottom