Baja Mini bike

[Gabriel]

What a pile of shet. Well...it was free. Tossed the chino motor. It weren't worth fixin'.
https://i.imgur.com/7pRS3hf.jpg


Mock up motor says there's enough room......I have a 185s engine almost built. Should be nice....and stupid uncontrollable. LOL!!!


https://i.imgur.com/iS3AbCN.jpg


Lots to do to make this what I want. BUT, I will start by getting the motor situated and in line with the rear sprocket. Everything else will come later.
I'm not sure yet but I am seriously considering setting this up as a trike. Time, headache and $$$ will dictate.

[Gabriel]

One of the first hurdles, post engine mount, will be the shifter. With the pegs so far forward I may have no choice but to go with a suicide shifter. Might as well. The whole dang machine is gonna be a death trap anyway.

[Gabriel]

Got all 4 motor mounts done today. I'm a pretty lousy welder so I gotta double down and excel at being a good grinder.
Much to smooth out BUT the engine sits square in the frame and is within a 32nd of the sprockets. I have to change the rear sprocket so I may make a shim for that.

I work with what I have on hand and rarely BUY metal to work with. The front mount is made from the supports to an old treadmill. The bottom is made from chainlink fence bars. The top mount is made from a shipping support bracket that bolted down the new tire machine we just got at work to the shipping pallet.. No idea what the other mount is made from.
After a good grinding wheel massage and a smear of paint....well, it'll still probably look like shet.


https://i.imgur.com/FWVKSkm.jpg

[Gabriel]

THe Baja rear sprocket was a different size chain and needed to be replaced. On a whim I was studying what I had on hand....A stock Honda rear sprocket uses a different bolt pattern....BUT, the rivets that hold the shock absorbing assembly are the EXACT same pattern!!! What?!!! So I drilled and drove them out and BAM! It bolts right to the rear wheel hub. What luck??!!!!!

I bolted everything up and it runs true. Put a travel indicator on it and it's got about .006 runout. I can live that. Also, the chain is now in perfect alignment. Blind squirrel found a nut!!


https://i.imgur.com/WwB7JQ4.jpg

[schlepp29]

That should be a lot of fun! I like the other one to. Pit biking on a whole other level.

[Gabriel]

First nightmare has happened.
I HAD to put the engine in the way it is to get it to fit. .........BUT it is impossible to put a carburetor on using shelf parts. I spent several hours sifting through chinez-bay intakes and NOTHING will fit and clear the frame.

...nothing else to do but MAKE an intake manifold. With little more than hand tools...this will take some time. uggghhhh!!!!

[Gabriel]

Got the first of 3 parts made. Engine side.
Still need to make the carb side and the connection tube.


Used some 3/8" thick 1018 I had sitting around. Lathe bored the hole first in a 4 jaw chuck, then drilled the holes. Then saw/filed the profile & sand blasted it.
My hand work isn't the best but the worst of it won't show once it welded, painted and installed.

https://i.imgur.com/67wl9Fu.jpg

[Gabriel]

Got it done. ...just hope it'll run. Pretty sharp angle. But let's be honest. The engine won't have to be super efficient to move this thing, so as long as it can be tuned to run smooth and reliable it'll be fine.

Still needs a liberal coat of paint to hide my lousy work.

https://i.imgur.com/lSOCRwe.jpg


But it clears the frame and will sit neatly under my leg.

https://i.imgur.com/u8heBdi.jpg





Now I need to start building the exhaust I suppose...or maybe the battery box.
Not sure what I will tackle next.
May need to take a step back for a minute just to make sure I'm not overlooking any elephants in the room.
Any potential problems any of ya'll see, please point them out.
One mistake I noticed AFTER i had it finished welded was I made the carb sit level with the frame sitting level BUT the frame doesn't ride level. The front sits up a little so it'll be tilted back about 15 degrees unless I lower the front, which I am no opposed to doing. I never liked the front end sitting up as high as it does anyway.
Thanks!




..



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[Gabriel]

Moved to the rear today. Still looking for stuff I need to make the exhaust SO, I got (2) .50 caliber ammo cans mounted. 3 mounts for each can and rock solid. Gotta cut the handles off and they'll get repainted when all the fab work is done.

One side will house the battery, rectifier/regulator and as much of the wiring as I can to keep everything clean looking.
THe other side is still up for debate. Storage or a fuel cell. I don't think I will ever fond a tank that will fit up there and look decent so I may put a fuel cell in there and feed the carb with a Mikuni pulse pump.


https://i.imgur.com/5TR2h5M.jpg

https://i.imgur.com/4Y8os8f.jpg

[Gabriel]

Funny. That last pic looks wonky but they are straight. I set them with a level to the frame.

[Gabriel]

My only other option (sans spending $$$) is a desert tank I have. It actually clears everything and making the mounts is gravy work......but I can't decide if it's OK or looks fackin' shtoopid. LOL

It's just sitting up there now. It will actually sit down a little better if the mounts were in place.
The front is OK. The bars all clear as do the forks. It's the junction between the seat and tank that is outta place.


https://i.imgur.com/TOjMlhs.jpg



It's a fat sucker but is seems comfortable.

http://i.imgur.com/1mgSGCn.jpg (https://imgur.com/1mgSGCn)

[Gabriel]

Well scrap that. No possible way to clear the carburetor. Mehh.

[schlepp29]

That's looking good I like It

[Gabriel]

Had to order another mandrel bent U pipe. Soon as it's here I will start the exhaust.

ANYONE have a suggestion for a muffler that would be nice and quiet???

The tractor muffler I used on the Goblin sounded nice but was a little louder than I want for this machine. Since NONE of the exhaust has been fabricated, I am somewhat wide open on muffler possibilities and locations. I haven't even decided which direction to route it yet.

[jb2wheels]

I bet you could copy some shifter ideas from cruiser forward controls?
Maybe use some junkyard sportbike rear sets?
Basically, pivot a shift lever by your foot with a pushrod back to another on the engine? Like a 350X rear brake pedal if you know what I mean.

Maybe adapt an OEM Honda exhaust from a 200X or maybe an older, small XR/XL thumper?
Not sure if anything would be more quiet than that?

Maybe on old school little supertrapp with few disks?

How important is ugly to your exhaust solution? Like using a car muffler ugly? Hidden in an ammo box?

[Gabriel]

I might look into that for the shifter.

I don't mind, ....actually looking forward to, making the exhaust.


I feel like I've been wallerin' in insulation. Spent the last few hours with a die grinder and a carbide burr. Worth it though....now...no one will ever know what a shite welder I am. HA!!

[Gabriel]

Not sure how well this is gonna work out but I got a generic filter box from ChinEse-bay for $15

If I use it, I will have to weld in a bracket to mount it and drill out the crap wood screws the lid is held on with; Replacing them with 5mm machine screws & lock nuts since it will be mounted upside down.

https://i.imgur.com/fkgqhIe.jpg


https://i.imgur.com/NzvyTfE.jpg



With a better suited and properly oriented clamp it just barely misses the seat.
https://i.imgur.com/f7I8YJm.jpg

[Gabriel]

If I'm being honest, i think I like this set up better. MUCH easier and will likely run better than the knock off 24mm PWK which is likely too big for a stock 185 engine. BUT that means I will have to track down a good carb. This one has screws broke off in it and the inside looks like it's been dry humped by a rust monster. It makes a good mock up carb though.

This airbox will certainly need a mesh screen added to the opening to keep trash out.


https://i.imgur.com/0zuG2rU.jpg

[Gabriel]

Final resting place for the airbox.

https://i.imgur.com/x9d45eR.jpg




Won this tank for cheap off Ebay. It's pristine inside. Should work out really nice. It even came with a bracket that was easily modified to bolt right on.

https://i.imgur.com/4vHCYMZ.jpg

[Gabriel]

Never could find a muffler that suits what/where I wanted....so I made one.

Here's the inside......
https://i.imgur.com/5soe8db.jpg




Here's (roughly) where it'll sit.


https://i.imgur.com/uxYUZ5O.jpg

[Gabriel]

Welder was down for a bit but, back in business....

Got the muffler mounted. I'm thinking of using some expanded metal scraps I have and welding some nuts on the muffler to bolt it in place for a heat shield.
Wonder if that would help keep heat away from the ammo can or just a waste of time???? Thoughts?


https://i.imgur.com/VL9cI1Z.jpg

[Gabriel]

https://i.imgur.com/WQVjv4X.jpg

[Tri-Z 250]

You haven’t had a good hard get off until you’ve experienced yard darting those pegs from leaning it over at speed! Lol

[Gabriel]

Those pegs are soon leaving here. Not sure what I will do but they gotta go.

[knappyfeet]

Diggin the vibe of this project.

Buildandclick.com for the exhaust.

[Gabriel]

Got The header totally done. Just need to wrap it on final assembly.

Still need to cobble a mechanical faster to attach to the muffler but it's up inside 2 inches. Should be a decent enough exhaust.

It sits an inch higher than the frame BUT I am now considering a sheet metal skid pan to protect the pipe.

https://i.imgur.com/eTjoUoj.jpg


Hopefully this heat shield will help since it's so close to the box. Time will tell.

https://i.imgur.com/yAqtKRK.jpg

[Tri-Z 250]

I could see some 1/2 hoop like nerfbars to look like floor boards/skid plate splash guards. I like military function look it has really going to be a cool camp bike.

[Gabriel]

I had the same idea tri-Z ....to protect the exhaust. Only problem I have right now is ground clearance. Too wide and it'll dig in a corner. That would suck...very much bad.

[Gabriel]

Ho Ho Ho...The jolly fat basturd brought me some new parts!
New fenders, seat & a pulse fuel pump.

https://i.imgur.com/HXFrmrX.jpg

[Gabriel]

Made some support strut for the tank to keep it from vibrating....

https://i.imgur.com/tZxQi7X.jpg

[Gabriel]

The fuel tank being in the back, the normal gas tank location needs something. ....gather up the scraps!!!

This will house a small 12v battery, regulator/rectifier and much of the wiring. I can drill into the frame from the inside and route wires where they won't be seen AND use the aluminum lid for switches and whatnot.

MUCH finish work to do....

https://i.imgur.com/jNZMekk.jpg

https://i.imgur.com/fZz0gxl.jpg

https://i.imgur.com/e9t0WNg.jpg

https://i.imgur.com/VCHwhNk.jpg

[Tri-Z 250]

Made some support strut for the tank to keep it from vibrating....

https://i.imgur.com/tZxQi7X.jpg


Good place to hang some dummy grenades....Dude you must be planing a cross Baja trip, that’s a long drink of petro’ amigo.

[Gabriel]

It's done and I think it turned out ok when one considers it's 95% leftover or homemade parts. I'm in this for about $250 total cash.
I think I nailed the color for the engine too; 70's Cadillac gold. Like any old caddy, smooth but not to be underestimated. Them old boats would sail and so will this one. BUT, it's extremely gentle and a VERY smooth power curve. I would have thought doubling the HP of the original engine and adding a 5 speed tranny would have made for a mean ride but this is pretty cushy. Well, as much as a rigid rear can be.

My homemade exhaust & muffler worked out nice and sounds really deep for such a small engine. Front brake conversion (never had fronts from factory) was a VERY wise decision.

https://i.imgur.com/TFsDfQW.jpg


https://i.imgur.com/5kUb947.jpg

[ATC King]

Road trip planned?

[Gabriel]

Heck yeah road trip...LOL!!

I didn't realize it until I was balls deep into the build....that right side can is gonna get toasty sitting over that muffler. BUT, it all works out. One could toss a hot pocket and a can of chicken noodle off in there and have a hot meal at some roadside rest stop. HA!!!!!!!!!

[Gabriel]

Good place to hang some dummy grenades....Dude you must be planing a cross Baja trip, that’s a long drink of petro’ amigo.

The tank is off (I think) an old Wisconsin engine. Could be wrong. It fit and was cheap. Since it sits almost level with the carb, gravity feed wouldn't be none too reliable so I used a pulse driven fuel pump that is fed from the crankcase vent. I put a T in the line that connects the two with a rubber cap. I'm observing as I ride. If I find an over pressure situation I can slowly open up a hole in the rubber cap for a dump vent and lower the pressure. Thus far I have seen NO issues though.

Talk about a long drink....Between the fuel line, filter, pump and what the carb itself holds....it'll run for two laps around my field with the gas shut off. LOL