Need some help 4 stroke issues...

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So here's what's up bought a nice micargi Seattle with a 49cc four stroke engine. It's set up like I've never seen one done and runs decent. However my problems started when I got a flat on the rear tire which led me to redoing the bike paint, bars, ect. Added a arch chain tensioner cuz there wasn't one on it when I bought it and the chain was a bit loose. Well I came into 2 mm80 4 stroke engines and think I'd like to mount one on this bike. But the way the clutch is it's going to be too high I'm wondering if my transmission will fit . Any tips will help. I'll post pics of the bike and the engine
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Sidewinder Jerry

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So are you saying you're wanting to remove the 4-stroke 49cc engine and put a 4-stroke 80cc engine on the bike? What's needed is better pictures of the larger engine. Chances are the transmission isn't going to fit and you'll need to do a jackshaft reduction setup.
 
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Yeah, that is exactly what I'm saying. The issue is that I have 2 mm80s and I'm trying to figure out how to mount them . As you can see in the pics I have a pretty standard 4 stroke set up other than the gearbox is pointing down
 

Sidewinder Jerry

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Looks like you have lots of room to work with. You could even mount the jackshaft behind the seat post. Seen a thread where it says to put the centrifugal clutch on the jackshaft instead of the engine. Said it'll put less wear on the clutch due to it moving at a lower rpm
 
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I'll be honest I'm not super experienced in the hobby been doing it less than a year. I've learned A LOT, like a staggering amount in a short time. But I'll admit I'm lost as far as a jackshaft. I'm also limited on tools. ..
I am also curious of the effect of the exhaust pipe on a 4 stroke. Does it effect the power and performance like it does on a 2 stroke?
I have one of those flex fit jobs that I think would look killer on this bike
 

Sidewinder Jerry

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The exhaust doesn't play as big of a role with 4 strokes as it does with 2 strokes. Things that improve 4-stroke performance are tuning the carb and adjusting the valves.

If you're going to be into motorized bicycles, it's a must to invest in quality tools and even specialty tools. As far as learning goes, you're in the right place to do it. My next big question is, can you weld?
 
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I'm learning now. I seen the value in it. I used to be a sheet metal fabricator back in the days and did a little welding and braizing. But the things I could do if I could weld. It would really open up a while new world of stuff I could do to bikes. I just bought a project bike off a guy and his son. Threw in a small welding machine for a hundred bucks. I'm just starting to play with it a bit
 

Chainlube

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I'm learning now. I seen the value in it. I used to be a sheet metal fabricator back in the days and did a little welding and braizing. But the things I could do if I could weld. It would really open up a while new world of stuff I could do to bikes. I just bought a project bike off a guy and his son. Threw in a small welding machine for a hundred bucks. I'm just starting to play with it a bit
Is that a flux core only welder? If so, make sure all your connections are clean and beveled before you start. Give yourself at least 1" of clean metal all the way around the joint.
 
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Is that a flux core only welder? If so, make sure all your connections are clean and beveled before you start. Give yourself at least 1" of clean metal all the way around the joint.
Thanks man I believe that's exactly what it is. I'm hoping to use it to make a nice pipe for a bullet train engine I have. As you may or may not know there like no aftermarket exhaust stuff for them
 

Chainlube

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Thanks man I believe that's exactly what it is. I'm hoping to use it to make a nice pipe for a bullet train engine I have. As you may or may not know there like no aftermarket exhaust stuff for them
If you look at my avatar bike, I chopped up a jog scooter pipe and made that one.
 
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