SAE30 16:1 observations

FreeWheeler · Sep 1, 2010

I ran out of homelite exact mix, was using 24:1. I had some SAE30 and played it safe by mixing it 16:1 and then filled the bike. The bike's tank had about 1/3 of a tank of homelite/gas mix. I noticed some interesting changes in performance as the 2 premixes mixed. At first, no difference and gas in the fuel line looked reddish - drinking good stuff. About 3 miles later, performance went down but was running smooth. Came in, parked it and noticed the color in the line had changed to golden - dirinkin the yucky stuff now. I went out for another ride a few hours later and woa, what was that. I was going about 20 on a flat when it took off and accelerated. I backed off, it slowed. Lets see if it's still there, zooom awesome. I went a few more miles and the awesome performance was gone. I even pulled in the clutch at one point and idle was nice, so it wasnt a sudden lean condition I dont believe.

What was that? Did I just break in, but now I got lousy gas/oil ratio?

2door · Sep 1, 2010

Freewheeler,
your experience has me wondering. If you've kept up with the old 100:1 thread you might have seen where I have one engine that will not run on that mix. In fact it is the worst running engine I have. I've been using regular 2 stoke oil @ a 32:1 mix in it but it still didn't perform anywhere near as good as my others. A couple of days ago I ran out of mix for that old engine and instead of mixing new I filled the tank with some snowblower fuel I had left over from last winter (I know, old fuel is a no-no) The snowblower uses a 50:1 mix so I didn't measure but dumped in some extra oil, yes, some SAE,30 W. I knew I put too much oil in and if anything exceeded the 16:1 and maybe was down close to 14. I went for a ride and had nearly the same experience as you did. The bike ran, OK, until it burned off what was in the fuel line and carburetor but then the heavy oil mix started flowing. That engine has never run this good. It still won't keep up with my others but the performance is noticeably better than it has ever run before.
Now, I'm by no means suggesting to anyone that they should start using SAE30 @16:1 but if anyone has an engine that just doesn't have the suds that you expect, it might be an interesting experiment to try. I know this is going to start a firestorm of discussion but I'm only tossing out something that I and now you, have experienced. Let's sit back and watch the fur fly.

Tom

BarelyAWake · Sep 1, 2010

I can only think of two things that might possibly contribute to this... one being the alteration of the fuel/air mix from such a heavy amount of oil (unlikely) the other being that the heavy mix was compensating for unusually low compression?

Other than that I chalk it up to that mysterious juju all machines seem to have... ya musta made yer blood sacrifices *begins chanting* @.@

Goat Herder · Sep 1, 2010

I am wondering if this is related? http://motorbicycling.com/f3/controversial-engine-break-technique-20092.html

Venice Motor Bikes · Sep 1, 2010

Here's what I think is happening... The more oil in the gas, the less gas is in the mix. (More oil = leaner fuel/air mix.)

Freewheeler, I think re-jetting your carb (smaller) will make your bike run better with a normal gas/oil mix.

Goat Herder · Sep 1, 2010

Reading this again I suspect the op's is not related to 2d. I was thinking of 2d in my first post. I believe 2d had previously tried different carb arrangements.

2door · Sep 1, 2010

My vote is compression due to poor sealing rings from initial break in that didn't do the job. Speaking of compression, I have not read where anyone has established a standard for these little 2 strokers. If you've ever used a good reliable (preferably a screw in type) compression gage on one please post your findings here. In the next few days I'm going to test the compression on five engines and see how the readings compare with the performance. Of course I know that higher compression equates to more power but what I'd like to know is what is high, low and normal.
Tom

bairdco · Sep 1, 2010

could it be that the secret is that since these motors were designed to run on 30w oil that's what we should be using? are all these synthetics and 100:1 mixes just a scam perpetrated by the Big Oil Companies? have we been duped into buying the Next Best Thing by scantily clad women in skintight Nascar Jumpsuits?

i feel so used...

r00t4rd3d · Sep 1, 2010

Super Klotz.

End of story.

2door · Sep 1, 2010

bairdco said:
could it be that the secret is that since these motors were designed to run on 30w oil that's what we should be using? are all these synthetics and 100:1 mixes just a scam perpetrated by the Big Oil Companies? have we been duped into buying the Next Best Thing by scantily clad women in skintight Nascar Jumpsuits?

i feel so used...

Way before your time, Baird, but there was once a Monroe Shock Absorber ad on TV. It was of a girl in very short denim shorts, a hard hat and work boots and a cut off 'T' shirt with 'Monroe Shocks' emblazoned across her ample chest. She walks through a construction sight where every dude there stops what he's doing and stares. There's no dialog except a voiceover at the end that says "When you need shocks, think Monroe...
Monroe shocks out sold every other brand that year...your comment reminded me of that and my devotion to Opti-2. Funny though, there was never an Opti-2 ad with a girl...Hmmmmm?
Tom

FreeWheeler · Sep 1, 2010

Great comments, suggestions everyone! I have nothing new to add just yet, no riding or tinkering today.

FreeWheeler · Sep 4, 2010

I've run a tank of SAE 30 16:1 and it doesnt dislike it. It's always said to only change one thing at a time to really measure effect of something, but that isnt always possible. Sometimes there are variables beyond control. For instance, the weather. The temperature dropped like a stone today from 100 degree days to mid 70's. Another factor was the idle screw fell off, so I have 3 variables which are different and only one was my choosing, the earl mix. It was running better than ever today, climbing hills better, sounded better, smoother less vibration. I pulled in the driveway and idle was high. I looked and noticed the screw missing, so I put my finger over the hole and the idle slowed.

I've put a temporary wood dowel in the hole and will run it to see if that slows the idle and how it runs. The weather should be very nice and cool again.

2door · Sep 4, 2010

FreeWheeler said:
I've run a tank of SAE 30 16:1 and it doesnt dislike it. It's always said to only change one thing at a time to really measure effect of something, but that isnt always possible. Sometimes there are variables beyond control. For instance, the weather. The temperature dropped like a stone today from 100 degree days to mid 70's. Another factor was the idle screw fell off, so I have 3 variables which are different and only one was my choosing, the earl mix. It was running better than ever today, climbing hills better, sounded better, smoother less vibration. I pulled in the driveway and idle was high. I looked and noticed the screw missing, so I put my finger over the hole and the idle slowed.

I've put a temporary wood dowel in the hole and will run it to see if that slows the idle and how it runs. The weather should be very nice and cool again.

Keep an eye on your spark plug. The high oil content could promote premature fouling but as long as it runs good...go for it. I've always been a firm believer in using what works for you in spite of what the experts say. If your engine likes 30W and lots of it...go for it. Keep us posted and I'm still running high oil in that old motor that didn't like Opti-2. Its running good and the plug is fine.
Tom

GearNut · Sep 5, 2010

_________________________________________

FreeWheeler · Sep 5, 2010

I pulled the plug tonight and it is dark, but only wet on the circular outer part. What bugs me is that maybe it ran great because it ran lean with the idle screw missing. The plug in the screw hole should eliminate that variable.

One difference(fancy mix vs. 30 W) I hear is that the engine had a hummm to it that was very intermittent very brief. Now, the hummm lasts longer and kicks in sooner.

I'll ride today and see what I notice.

Pablo · Sep 5, 2010

Here's the problem with running SAE 30 engine oil: TOO MUCH ash. The zinc from the ZDDP will foul your plug. May not happen right away, but may leave you stranded. Stick with 2-stroke oil.

FreeWheeler · Sep 5, 2010

I have a GPS log of when it was first installed and the average speed was 14MPH, 20 Maximum. I logged another 4 mile loop tonight and the average was 19 MPH, 25 Max. It's not just sounding better. As for the missing idle screw, the wood dowel stopped up the screw hole and idle is normal again. This carb is getting uglier by the day. The brake has an issue now too. I'll post a pic for laughs.

The weather is going to get hot and humid again, so I'll keep running the SAE30 and see if its just better weather.

FreeWheeler · Sep 5, 2010

Here's the sloppy carb. Idle screw replaced by wood dowel and sealed(outside only) with more RTV. Loose choke lever held down with silicone tubing - still allows to choke by holding in place.

2door · Sep 5, 2010

Yep, that's ugly...but who cares as long as it runs? In circle track racing there is an old saying: "You can't see it from the grandstands"

Keep us informed.
Tom

FreeWheeler · Sep 14, 2010

The bike sat for a week while I fixed the Hub issue and got new bolts for the tensioner. The brake arm stripped because previous owner(s) had twisted the arm up probably by not attaching it to the frame, and so it didnt lay flat against the cone. Like a cockeyed wrench on a nut, it slipped and the cone bored it out round. I replaced it with a Shimano D-type arm and put everything back together tonight.

So, it sat for a week without running and when I tried to restart it took a while. It did start and I managed to go up and down the street for a few passes and then it ran out of gas. If the gas drops around the level of the hump in the tank, it runs quits runs quits until I wise up and fill it. I filled it with the last of the SAE30 mix.

As for ZDDP, that is an additive which is disappearing and alot of older cars need single weight and ZDDP. That's not good for the car collectors. I have two types of SAE30 in the garage. One type is for pre 1930 cars and the other is very new spec which doesnt have enough ZDDP. The pre 1930 SAE30 says it has no additives at all, straight mineral oil.

I dont think either oil is a problem, but if you have some thoughts on it, let er rip.

SAE30 16:1 observations

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