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Discussion Starter · #1 ·
Hey everyone!

Just wanted to say that I'm very happy to be a part of this forum. I've been reading as a visitor for quite some time and finally thought it was time to make an account. I've been working on engines and cars since a very young age. I got into pocket bikes about a year ago and instantly started to like them. It's nice to find a place where people love these bikes and don't bash or make fun of them.

I currently have a 49 cc super dirt dirt bike (12in tires) that I have done a lot of work to. I got it as a parts bike for a really good price. It came with alot of extra engine parts so I decided to fix it up. I then decided to customize the frame and currently, build up the motor (44mm "stage 2" bore, full circle crank, fiberglass reeds, bosch plug wire with ngk plug, "performance" 3 shoe clutch, ported and polished stock carb with new jet, v-stack with pleated air filter and, of course, a good quality fuel filter). I also made up a gasket and modded the torque box to enable it to hold gear oil. I had it off road several times before the engine build-up and the thing was pretty fun (proper air filter already in place).

I have a few questions to ask regarding proper re-assembly of the engine. I'm assuming that it all comes down to proper bolt torque, thread lock in the proper places, and lubrication as you go along just as you do in a 4 stroke (Minus timing, lift adjustment, and all of those good things, of course!!!) I'm here to learn.

Thanks a lot for reading and, once again, I'm honored to be here finally. Happy new year everyone!
 

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Not really 2 stroker building is a lil different than 4 stroker building.....The proper torqueing,,loctite and lots of lube is right on track...2 stroker pre-mix oil is whats used for 2 stroke engine assembly

You need to know calculated squish and compression ratio to know how to run your engine with proper fuel octane.....

2 strokers thrive on velocity more than 4 strokers therefore blueprinting the mill to deliver true performance is needed to do without adding too much volume.....

re-port timing the ports will change the characteristics of the engine to mad agressive and powerful if done right........

These engines were designed for lawn equipment and are built retarded in ignition and port timing to get longevity and ease of useage out of the equipment its bolted to without running problems.........To get real true performance the engine must be lifted from the lawn equipment power realm into a new attitude of performance...........

Theres lots of DIY mods that can be done to enhance the perf on the cheap................Good Luck and Welcome to the Forum
 

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Git R Dun PBracer
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Welcome to pbp. :)
 

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Welcome to the nightmare. The Big Bore kits still need porting & timing and squish, they might have alittle more compression, or not. You never know what your going to get in a Kit. I spent a year on a 3rd stage B/B engine kit to find the new cylinder was warped. I gave up and sent it to Sam, Boosted306 here and he fixed it and shipped it back, ready to rock and roll. New means nothing on with China parts. CAM2 will tell you sometimes the kit is worse than a stock engine. I have seen kits that had 2mm of squish, .5mm is better.
So, check out CAM2 posts, they are full of photos and text that tell you what to do. You can do alot with just a few hand tools.
 

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Discussion Starter · #5 ·
Thanks for the input everyone, I greatly appreciate it.

I have not gotten into the big bore kit yet. I've heard mixed things about them (what can you expect from china parts..) but I thought that I would give it a try. The cylinder walls and all components LOOK ok, but that doesn't mean anything. I wouldn't throw anything together without tinkering around with/ adjusting it anyways. It would be much appreciated if someone could like me to posts about big bore adjustment, etc. I have a fair garage full of mechanics tools (no drill press, though), so that shouldn't be an issue.
 
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