Good snatch up help 3.5hp briggs project?

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TheSignGuy

Member
Nov 24, 2014
459
9
18
seattle, wa
Hey it's been awhile and I see the site has full upgrade.


Anyway I just snatched up a good

D-am
O-ld
D-usty
G-stage
E-ngine

Briggs & Stratton 3.5HP with good compression for $15.00 locally that was originally $20.00.

The major factor on why I snatched it up because it's full of trash in the carb after first look, the governor springs a little weak but functional, well worth the $15.00 and it included the clutch which apparently appears to be only 2-3 years old.

Surprisingly enough it had no oil in the case bone dry but that's not why I am here.


I would like to know would this particular engine fit in a pocket bike frame?

"That would make it not road legal."


My second option is if I am intend on installing it on a bicycle rack so it can be removed to prevent theft.

"Thinking of installing on a dahon or an old time scooter that had the rack on it."


Can someone provide me options that are closest to road legality?

I can actually go to a junk yard and design a turn signal system.


The design has to be mad crazy looking to run for a whole year then slap $500 on the sale price as it will be foldable.

"Safe enough to store "INSIDE" my RV CHAINED DOWN"
 

MEASURE TWICE

Well-Known Member
Jul 13, 2010
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I'm not sure I understand what is meant by removing the engine. If you mean each time you lock the bike up at a bike rack remove and take the engine somewhere else to store it so the bike is not more of a theft target, it sound like a project. I'm not knocking it, but it is nothing I ever heard of doing. My bike custom DIY Briggs is quite a time removing the engine that I found using a oil pump to change out the oil is what I did last time and will continue to do.
 

TheSignGuy

Member
Nov 24, 2014
459
9
18
seattle, wa
I'm not sure I understand what is meant by removing the engine. If you mean each time you lock the bike up at a bike rack remove and take the engine somewhere else to store it so the bike is not more of a theft target, it sound like a project. I'm not knocking it, but it is nothing I ever heard of doing. My bike custom DIY Briggs is quite a time removing the engine that I found using a oil pump to change out the oil is what I did last time and will continue to do.
Yeah I've had a lot of motorized and non motorized custom bikes stolen but I'm most interested In a dahon so I can "fold the enemies" eyeballs straight out of thinking stupid.

Keeping it inside with me or making a detatchable setup are my only two options, if the enemy wants to come inside good luck trying to steal while I'm home cause I have a breaker bar 24 inch ready this time to split a skull plate.



Anyway, most of this post consists of "mounting technique" I prefer rack mounting if anything, as well can I put 10w-40 in it temporarily to get it up and running?

I know briggs calls for sae 30 but I know also that this Briggs is a 4 stroke so for the first run time in how long god knows would be beneficial.


Oils these days contain a lot of detergents, which is why in older automobiles 1972 & below it is crucial to get it right the first time as zddp/zinc has been decreased in modern oils.

If the top end goes out most likely I will be installing a high tech low compression piston for a small turbo applications.



Removal by rack without detaching the mounting position of the motor is my drift.
 

TheSignGuy

Member
Nov 24, 2014
459
9
18
seattle, wa
10-40 will blow it up, run what's recommended, 5w-30 Dino oil

It's all set up now Briggs told me 10w-30 so this morning when I got home from around the world wife 4th of July "kicking it missions" i soaked the bore in wd-40 at 3am this morning, pulled the cord a couple of times, then filled the bore with WD-40 it, then the case with synthetic 10w-30 and let it sit till 9am.

Brought some carb and choke cleaner at about 9:35am while the braid heads were still sleep from a gas station, pulled the carb, pulled the jets needle valve from the bottom, shot it full of cars cleaner, and shot the intake side full.

Last, I shook it up, dumped access the air filter port, sprayed til it ran clear, took a transfer pump, and shot some air through the jet port.

Set the cart to two turns after firm and fired right up on inline filtered trash fresh gas...

Now my problem is a flywheel key as when I brought it out of my storage the clutch some how just fell off the block that and finding bike preference.


I'd prefer a dahon 6 speed but you know these people wishy washy about trading auto repairs for a "bicycle"


Has to be small or foldable so I can "fold up" on they stealing tweaking hind parts HAHA!
 

Tony01

Well-Known Member
Nov 28, 2012
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sf bay area
Sounds like a waste of wd40. You do not want any of that stuff seeping through the rings into your oil as it is flammable. Run the cheap stuff non synthetic and put some zinc additive in. Or just run it as is. Won't matter much till you modify the motor. Shave the head .030", cleanup the ports with a dremel or long bits in a drill, make the exhaust real smooth and make s header port matched to the exhaust port. Sand down the exhaust threads some too.

Flywheel key is on the opposite side of clutch key. Cutting a key for 6 degrees advance worked great for me.
 

TheSignGuy

Member
Nov 24, 2014
459
9
18
seattle, wa
Sounds like a waste of wd40. You do not want any of that stuff seeping through the rings into your oil as it is flammable. Run the cheap stuff non synthetic and put some zinc additive in. Or just run it as is. Won't matter much till you modify the motor. Shave the head .030", cleanup the ports with a dremel or long bits in a drill, make the exhaust real smooth and make s header port matched to the exhaust port. Sand down the exhaust threads some too.

Flywheel key is on the opposite side of clutch key. Cutting a key for 6 degrees advance worked great for me.
Correction, clutch key, would one from ace hardware work?

It seems pretty healthy, i don't plan on keeping the synthetic for long just wanted to wet the motor with micro pours oil... I let it run it doesn't pop or nothing, the only down side the true tuning won't come til I have a long nose bmx with a rack. My motor mount will be a block of 2x6 shaved to drop perfectly on the rack.

But the oils black already, so going to need to change it again.
 
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Tony01

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Nov 28, 2012
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Yup 3/16" square will work.

Wood won't work for a motor mount.

The oil will always go black. It's just the small amount of blowby that is causing that.
 

TheSignGuy

Member
Nov 24, 2014
459
9
18
seattle, wa
Yup 3/16" square will work.

Wood won't work for a motor mount.

The oil will always go black. It's just the small amount of blowby that is causing that.

Why won't wood work on a bike rack?

Also I remember when I first put the oil in it was separating in two colors crystal clear brown then when it was getting close to full it had a few streaks of a powdery silverish gray keep in mind it was bone dry as well as garage kept.


It wasn't metal flakes though I ran the motor for about 5 minutes at first then checked the oil and the color disappeared, and the oil begun darkening.


No smoke from the exhaust, yesterday I let it run for about 15-20 minutes and it did not pop bog or sputter as well.


Proven it's healthy enough to use meanwhile it was so hot yesterday my 2 stroke had top end spark knock with the correct mixture.

I still don't see why a block of wood won't work it will be bolted on the underside with a steel band strip to allow the wood proportion to lock on the rack.


What makes the difference is I'm looking for a bike with a solid steel rack.
 

Tony01

Well-Known Member
Nov 28, 2012
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Don't run it on synthetic oil ESPECIALLY not as your first oil. Run dino oil for the first few changes. Change the oil first time after 30min.

Wood is going to fall apart.
 

TheSignGuy

Member
Nov 24, 2014
459
9
18
seattle, wa
Don't run it on synthetic oil ESPECIALLY not as your first oil. Run dino oil for the first few changes. Change the oil first time after 30min.



Wood is going to fall apart.
Yeah overtime but not instantly, what is dino oil as well the engine is old I doubt it will fail because it's already broken in and it sat in a garage dry cased did not have debris in it I did a base scrape test as well no flakes.

Not that I'm hard headed I just don't see how or why it would fail I ran it in the night as well to confirm it does not overheat.

Any Briggs that glows cherry red at the exhaust has issues or is running lean in theory the first test run would be best time to change the oil right?