From scratch build

[Desertduler]

Is there anything I'd have to do to the engine besides adjusting the carbs and oil pump for warm weather? Anything to help with cooling the engine?

No, you will be fine, just make sure that at wide open throttle the oil pump indexing marks line up together, I do not use oil injection I mix my fuel with oil 25:1 air cooled two stroke oil. Do not use tcw3 oil which is formulated for outboard motor use as it does not have good enough film strength for air cooled two cycle engine use. Make sure that the axial fan belt is in good condition and adjusted properly and check all the cooling fins on the cylinders and cylinder heads and make sure that they are free of any debris of any kind and clean them if needed and for sure do not use a K&N filter or any fabric filter like them as they let dust through them which in turn will eat your engine components up, use a foam air filter and treat it or them with foam air filter oil which is very sticky and traps dust,dirt,sand,etc.

 

[Poboy kartman]

Great....now I gotta throw out salad ,too! I've been dressing them with air foam oil...(thought it was liked whipped cream).....and cleaning vinegar! JK.

 

[SkidooTNT]

What's wrong with using the mechanical oil pump on the motor?

 

[Poboy kartman]

IDK...But for whatever reason, a lot of people either don't trust them...or have had bad experiences with them....

It makes sense that a pre- mixed fuel source would have a more homogeneous mix and be virtually fool-proof. But I'm not a two stroke guy....(I use up 3 just putting! )

 

[SkidooTNT]

Guess I'd just like to know why? Know I have to find an oil that is heavy enough for warm weather and thin enough for the oil pump. I'm mean it's literally designed for the motor.

 

[Poboy kartman]

Guess I'd just like to know why? Know I have to find an oil that is heavy enough for warm weather and thin enough for the oil pump. I'm mean it's literally designed for the motor.

I hear ya...I tried to explain why...perhaps another reason is most two stroke guys are old school....and maybe the first oil injection engines were problematic....IDK....

But concentrate on what I'm saying...the oil pump is a convenience...that a lot of hard core two cycle guys don't care for....(maybe they think they're for dummies that can't mix their own gas and oil.)

But....like I said, it's hard to argue pre-mix is practically fool proof, while any blockage or pump failure can destroy an engine in short order.

Would I pre-mix? Probably not...I embrace the modern conveniences that help me be lazy!

Maybe some hardcore 2 sicklers will chime in...

 

[Desertduler]

What's wrong with using the mechanical oil pump on the motor?

Nothing wrong with using the stock oil pump, I just don't use them because of simplicity reasons, there are many oils that are designed for oil injected two strokes, maybe you need to research for yourself the difference between outboard motor oil TWC3 and air cooled two cycle motor oil and make your own judgement to as why I would suggest the type of oil that I did. Best of luck with your build.

 

[Poboy kartman]

THIS is the guy that knows two strokes inside and out!!!!^^^^^^^.

He's like E.F.Hutton....when he speaks....everybody snickers....errrr...I mean listens!!!!

Seriously, this guy knows his stuff ....check out his threads.

 

[chancer]

https://www.youtube.com/watch?v=2MXqb1a3Apg

 

[MonsterBike]

The thing about oil injection, it is great as long as it works. I wouldn't use pre-mix if I had oil injection. And even of the pump stops working, the motor will run quite a while on straight gasoline. After a few hundred hours, the engine will be "seasoned" with residual oil, This oil will lubricate it for at a surprisingly long while until it locks up.

 

[Poboy kartman]

The thing about oil injection, it is great as long as it works. I wouldn't use pre-mix if I had oil injection. And even of the pump stops working, the motor will run quite a while on straight gasoline. After a few hundred hours, the engine will be "seasoned" with residual oil, This oil will lubricate it for at a surprisingly long while until it locks up.

I call BS!!!!! Go ahead and "season" a few and see who gets surprised!

 

[SkidooTNT]

Thanks for the advice think I'll stick to injection. I'd be the guy that forgets to mix oil in with the gas...

I'll try to post my new frame concept in the morning if I can get it to work. Could only get one picture up last time.

As for a "seasoned" motor maybe being cold in the winter on a sled but I'd think in the summer anymore then a minute or 2 with out oil would do the motor in. Have to agree with Poboy on that.

 

[SkidooTNT]

I'm posting a pick of my drive train concept as well. It's really just a concept so nothing to harsh please... It's kind of hard to see but I'd like to have more then 1 gear ratio.

 

[SkidooTNT]

Bottom frame

 

[SkidooTNT]

Upper frame

 

[Poboy kartman]

Here we go again....

Good luck with that...but hey...if you can make it happen....more power to ya! But I'm not putting any money on success with that concept.

 

[SkidooTNT]

Assuming that's about my drive train concept....

What do you think of the frame? It'll be made out of inch and a half square tube and it'll be a 2 seater.

 

[Poboy kartman]

Assuming that's about my drive train concept....

What do you think of the frame? It'll be made out of inch and a half square tube and it'll be a 2 seater.

Yeah...really hard to tell exactly what you have in mind ...maybe later on it'll make more sense...(or less.)

Actually, for the frame...I wouldn't go 1 1/2" square... I would go with a rectangular tube...you could go 1×1 1/2. maybe. or even 1×2" would put the strength where you need it without just unecessary added weight...JMHO.

 

[SkidooTNT]

Upper frame mounted above the lower one with a lot of cross bracing.

At the back of the lower one (the part that's not really connected) is the rear suspension.
Above that part the engine would be mounted. Shocks wound go between in that area.

 

[Poboy kartman]

Upper frame mounted above the lower one with a lot of cross bracing.

At the back of the lower one (the part that's not really connected) is the rear suspension.
Above that part the engine would be mounted. Shocks wound go between in that area.

This is getting worse all the time....I would hope you plan a jackshaft on the pivot point....but really....a double frame? With cross bracing? Why not just 1×1? Maybe 1×2 for the swing arm part.