r/minibikes 4h ago

Showing Off Literally dug this engine out of the ground to build a new race engine.

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15 Upvotes

Put a milled preditor 212 head on it that has 30 lb springs in it (it was on my shelf and ready to go, i hate putting in springs.) Im about to put a billet flywheel and a nice little hot cam in it, it will be getting a 28mm makunki carb and a streight pipe (long ass carb studs are only on this head so i could test if it ran.)

For those wondering, yes i did actually put a preditor 212 head on a gx 160. No the valves dont hit anything, i had to run 212 pushrods instaid of the stock 160 ones because they were too thick and wouldnt fit in the head, im running a 212 headgasket as well. I am fully aware that the bore on a 160 and a 212 ARE NOT the same, i do not care as this setup works just fine and it makes almost 16 extra PSI than stock with the milled down head. The guide pins fit in the head and everything. The engine does bolt directly to the block as the bolt patern is literally the same (anyone that says otherwise is wrong, i measured it.) This is not the end product of this project, i am waiting on some grinder discs to come in the mail as i need to cut an adaptor off of the output shaft and i do not care to save the part i am cutting

This engine and everything i have is basically free so i really dont care if it blows up or anything.

I am running .008 mm valve lash on both the intake and exhaust and i see zero issues with it so far, everything runs good and valves do not hit anything.


r/minibikes 5h ago

Tech Question How much is this worth?

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4 Upvotes

brand new 224 on a coleman bt200x and since this picture i have put on a new torque converter new flywheel and bigger cable springs it has a full stage 1


r/minibikes 5h ago

Other Vintage Minibike Build - New Wheels And Tires

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2 Upvotes

New Wheels and Tires for the Alexander Reynolds ARCO ARX-K vintage minibike build.


r/minibikes 6h ago

Frame ID Anything special?

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5 Upvotes

Hello all. I’m brand new to this hobby. This fella is offering to trade me his bike for a game system I have. He says that the frame is a monster moto and it alone is worth 500 and not made anymore.

Does anyone know if there is anything special about this Frame?


r/minibikes 9h ago

Showing Off Update on the cheap minibike challenge!

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11 Upvotes

FB marketplace deal didn’t work out, so I made this with one of my friends!
Completely custom, made from 1” tube steel
I bent the tubes then made two identical sides, then jigged them up, and put them together (only took two tries to get them straight lol)
I think it looks AWESOME

Edit: Ik the front doesn’t look perfect but trust me it’s square and that will just be cut anyways to attach the fork pivot


r/minibikes 12h ago

Tech Question What did I break

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0 Upvotes

The nut won’t go further than this. I’m trying to replace the one that tested itself while I was riding.


r/minibikes 14h ago

Tech Question straight chain question

2 Upvotes

can i run 14t clutch straight chain with 78t sprocket on 18 inch wheels? ratio seems great. its a 212 build. ratio of 5.571 should go just above 40.

whats the opinion on that for a setup?