Quick video of my Honda Cub clone
 

This is the very first video I have ever posted on the net.

View My Video



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That's a sweet little bike.

I would ride that.

Its very fun and extremely easy to ride. Everyone that sees it loves it.


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that looks like fun

Very cool bike....

Ok so mentioned in other posts I replaced my 49cc engine with a 125cc engine. Increase in power of course was dramatic to say the least. I then became concerned my original 49cc exhaust would/was/is too restrictive for the larger engine. My exhaust has that single little outlet pipe maybe the size of a nickel in the center of the exhaust plate. So I finally purchased some step drill bits and I drilled 4 holes all as the same size as the original hole evenly around the exhaust plate. Immediate improvement on idle, performance and sound. Power lag when taking off from a stand still is significantly reduced. All 5 holes have what feels like an equal amount of exhaust pressure coming out of them. So my question is how far do I go with these holes? Do I stop right where I'm at well enough to leave alone? I have seen YouTube videos where you now take a long drill bit up to 18" or so and drill in through the new plate holes and you will be able to drill through all the plates inside the exhaust to open it up even more. How do I know if I need to open it up more?


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When the exhaust starts to lean out. Check plug possibly or add just a little choke to see if it runs better?

I do know its running leaner as it was backfiring during deceleration. I am waiting for it to cool off before I pull the plug. So does this mean I stop or open it up a little more?


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If it starts to lean out, you can always step up the main jet to compensate. Super easy and cheap.

You can determine the ideal size with a little math. Remove the header from the cylinder head and measure the ID. Once you have that, you can calculate the area of the inside of the pipe. When drilling holes, determine the area of the bit size you've selected, and then drill enough holes to equal the header ID area.

Make sense?

That's a cool project. Looks like a better riding position than a Grom or Mad_ss. I bought a 1969 Honda S90 a few years back but never restored it before selling. It was too big of a project for me. Did the original 50cc engine have pedals like a 70s moped? Was the 125cc engine a simple bolt-on?

Riding position is great and I am 6'1" 220lbs. No pedals. These Honda horizontal engines mount with 2 thru bolts and it falls right out the bottom of the bike. Its not easy but I was able to change out the engine myself by cradling the engine in my arm like a baby lifting it into place and sliding one of the bolts in. There is a video of a guy on YouTube that straddles the bike and simply reaches down with both hands and liftis the engine into place then traps it with his foot while he slides the bolts in. Of course you still have to deal with the chain and exhaust but thats simple stuff. You can not believe the compliments I get on this bike by anyone in the 50 years old range and especially anyone that is Brittish/English.



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This just arrived today from China. New Mikuni with fuel lines, throttle cable and pod filter package. They should have thrown in a fuel filter for the ultimate package. Not a bad deal for $40.00. I don't know anything about throttle cables. I hope it will work on my bike. Its a vinyl covered braided cable, I like it.

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http://i63.tinypic.com/al3ssk.jpg


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http://www.aliexpress.com/item/125cc...217872075.html




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Good deal! It's cool that the choke is on the left side; several of the Mikuni carbs I've seen for horizontal engines have the choke on the right.

Ok I got my new carb on installation went good. However it is idling way to high. I can turn the idle screw in and make it idle even higher but when I back the screw out I can't drop the idle down into the 1500rpm range. It stops dropping around 2000rpm. Do I need to purchase a couple smaller pilot jets? While I'm at it do I need to purchase a couple smaller main jets? I currently don't know what size jets I have. But the reason I bought this Mikuni carb is so I can re jet it and hopefully get the optimum tune. Also where should I set the needle position? My needle has what looks to be at least 6 or so clip positions. Thats whats good about these Mikunis is they are so adjustable.

Thanks for the help.



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