79cc Sportsman Flyer build

Tom from Rubicon said:
Been still thinking of venting the crankcase, in similar fashion. On this forum there is no empirical data or experience.
Returning the blow by oil from the catch can to the crankcase is worth looking at.
A one way Lee Loc valve might work. Check Valves - The Lee Company

In a few Sportsman Flyer Bonneville photos there were fleeting views of such a system. Pat never got back to me.
No big deal. He has a heavy work load, and I will sleuth it out. The lube in my Flyer is the same I run in my R80/7.
15-40. Air cooled engines like it.
Tom
Click to expand...
I use 10w-30 synthetic. Never had a problem. I still have a lot of work to do on my engine though, so I look forward to reading about what you do tom. Might give me some valuable insights. I plan on doing a port and polish once I get the new flywheel agk is selling now, get more power out of this little thing, so if you do that, some detail would be nice to have.
 
Norm, of Venice Motor Bikes started a Mini Bike thread in the Tavern. One of his mini bike photos has a tube from the valve cover to the oil filler port. I had wondered if that was an option to using a catch can.
Tom
 
Tom from Rubicon said:
Norm, of Venice Motor Bikes started a Mini Bike thread in the Tavern. One of his mini bike photos has a tube from the valve cover to the oil filler port. I had wondered if that was an option to using a catch can.
Tom
Click to expand...


My engine has a vent hose from the top of the case to the valve cover because when I had the case sleeved for the 3" piston, the factory vent inside the engine was filled.

For the 70cc Predator, you can simply run a vent hose from the valve cover to a small 'vented' oil catch can...
In your picture you have the catch can vented to the intake air filter which will work fine.

Here's that pic of my case vent hose... Mine also serves the purpose of extra oiling the rocker arms.

mm2.jpg
 
Venice Motor Bikes said:
My engine has a vent hose from the top of the case to the valve cover because when I had the case sleeved for the 3" piston, the factory vent inside the engine was filled.

For the 70cc Predator, you can simply run a vent hose from the valve cover to a small 'vented' oil catch can...
In your picture you have the catch can vented to the intake air filter which will work fine.

Here's that pic of my case vent hose... Mine also serves the purpose of extra oiling the rocker arms.

View attachment 107899
Click to expand...
I'm just curious if this actually relieves crankcase pressure? If that pressure isn't relieved, oil will wind around the crankshaft, it will foam faster, and it resists the downstrokes of the piston, sapping power, throttle response, and of course, fuel efficiency.
 
IDK if anyone would like to use this design of a CAOS Breather (crankcase air oil separator)
The CAOS is in the seatpost
Here is a CAOS Breather I made (invented) for my Whizzer M/B.
I call it the Seatpost CAOS Breather
It's better than an oil catch can because when ya turn the engine off any oil in the CAOS will gravity drain back to the crankcase.



motoredbikes.com

Make a COOL Crankcase Breather for your New Gen Whizzer

Howzit Everyone, Just thought I would share with ya all how to make your own CLEAN and COOL looking Crankcase Air Oil Separator. C.A.O.S. The PVC C.A.O.S. or the Big Rubber Hose C.A.O.S. can look very homemade. I guess that's why people say it makes the bike look like it's on Life Support. With...
motoredbikes.com motoredbikes.com
 
wrench said:
IDK if anyone would like to use this design of a CAOS Breather (crankcase air oil separator)
The CAOS is in the seatpost
Here is a CAOS Breather I made (invented) for my Whizzer M/B.
I call it the Seatpost CAOS Breather
It's better than an oil catch can because when ya turn the engine off any oil in the CAOS will gravity drain back to the crankcase.



motoredbikes.com

Make a COOL Crankcase Breather for your New Gen Whizzer

Howzit Everyone, Just thought I would share with ya all how to make your own CLEAN and COOL looking Crankcase Air Oil Separator. C.A.O.S. The PVC C.A.O.S. or the Big Rubber Hose C.A.O.S. can look very homemade. I guess that's why people say it makes the bike look like it's on Life Support. With...
motoredbikes.com motoredbikes.com
Click to expand...
So Wrench, what ever CAOS oil then drains to lubricate the crank set bearing?
Tom
 
Tom from Rubicon said:
So Wrench, what ever CAOS oil then drains to lubricate the crank set bearing?
Tom
Click to expand...
Any oil gravity drains back to the crankcase and just rejoins the rest of the oil.
Your oil level don't go down as it would if the crankcase vent was being dumped in a (puke) oil catch can.

The blow by air venting from the CAOS can also be directed into the carb intake if one want's
 
Tom from Rubicon said:
I must have missed a turn in your plumbing.
tom
Click to expand...
I explained in my instructions in the LINK of how to make the Seatpost CAOS Breather
That I had epoxied a rubber 7/8" stopper inside the seatpost right below the hose fitting so no oil will get into the frame. Any oil will gravity drain back to the crankcase.

Only air comes out of the CAOS and any oil gravity drains back to the engine crankcase
 
My intention today was to begin machining a better brake arm mount.
All thought out but..
I had some BMX pedals needing band saw mod, and then. Existing pedals won't unscrew. Used Red Loctite.
Why I did I do that?
Sunday I go at them (the pedals) with the propane torch. Comedy of lack of observation.
The pedals, I bought and installed on the Flyer originally were toe clip pedals. They are asymmetrical. They will be perfect replacements on my Schwinn Paramount which has lived with cheap steel pedals.
BMX pedals are symmetrical. Photos coming once mounted.

Mona, made a crazy good sauce for spaghetti today. Sautéed peppers, onion, garlic, zucchini, fennel bulb, and hot and mild Italian sausage, bathed in marinara sauce. I didn't have a hand in it. If I did, and it is never too late. anchovy's and Katamala olives would have gone in. Anchovy = Umami.

Tom
 
Sunday drive with "Miss Daisey" Mona, took us to Horicon, Wisconsin. I was in search of a Pork Tenderloin Sandwich.
One is offered at the Rock River Tap, About Us (rockrivertap.com) true Wisconsin bar vibe. Pre Prohibition back bar, well lacquered in nicotine. Very up North for South East and New Glarus Spotted Cow wheat beer on tap.
That is the good news.
Granted, Mona and I and two other couples at noon were in an establishment that could seat a bakers dozen at the bar and dining for at least sixty.
The tenderloin sandwich was eatable dressed my way catsup, tomato, and onion.
I was a cook at a Dog N Suds so I know what a good one can be. I think it was the fry oil. Beautiful skin on Russet French Fries just eatable too. If I was to run a fast order kitchen and want to draw customers in I sure a Hades wouldn't deep fry in canola oil, I would go old school Micky D and beef lard in. Either first fry or final finish fry.

So after all that. back in the shop with a Bernzomatic. Dumkoff me had loctite'd the pedals I wanted to remove. Had to.
Those pedals removed were Campagnolo clones for toe clips and never stood right side up.
Replacements are BMX rat traps with symmetrical foot thread. The clones well serve on my 1972 Schwinn Paramount.
Tom
 
Cool for pics of the new pedals. I remember you saying the campagnola clones would not stay upright, I may have a similar problem.
 
"Seen it right off" as Bear Claws Chris Lapp said. Mind you, there ain't no photos yet Crank arms too fooking HOT!

Honestly ain't no one but you gonna know, but yer shaving in the mourning looking in the mirror at who put those pedals on.
Have a beer and think on it. I even made copper counter weights that didn't work.
Here is a photo of the Rock River Tap and right across the river is the John Deere lawn tractor works.
IMG_3110.jpg

Harley Bar for sure.
 
Campagnolo clone pedals, note the asymmetry.
I even counter weighted them to self right. That was a wasted day.
Had there not been beer to keep me cheerful. I didn't get a manicure so don't look.
Some of the books in the background, may be of interest. Tiny tip of the iceberg those are.
The new modified BMX pedals are installed without Loctite.
For Steve. I made GARLIC bread tonight, crushed garlic, grated fresh Parmesan, and alot of first pressing vintage'd EVO.
Tom
 

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Remounted tire on the rear wheel today. The Goodyear inner tubes are rather bulky. getting it settled in the tire carcass is always a fiddly operation. I pressurize the tube at least four times. I gently lock the valve stem out with a vise grip and no valve so as to speed air evacuation. once settled, valve goes in and I pressurize the tire.
One thing I do to aide inner tube moving freely in the tire carcass is coat it well with talc powder to slick things up.
Tom
 
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