49cc Boosted306 Ported Zenoah Head to Scooter

2669 Views 8 Replies 5 Participants Last post by boosted306, Jun 15, 2012

EPR

Discussion Starter · Jun 9, 2012 (Edited)

The 48cc engine which has the new 42.7mm bore cyld, smaller than 44mm, started as a electric start, which I had no battery or solnoid or start button on my scooter. Put it in to replace the manual start engine to build the cut cyld w/ Cag Alloy head on top. Wanted more power for my scooter, so I got a Boosted306 Ported Head, pulled the old cyld and started building the new engine. Just put on the Walbro WT-813 w/ modded 15mm WYK copy alum manifold w/ boost fitting.
The first probem was getting the starter alum housing and windings, off with out damaging it, which I did. Had to make a 8mm long bolt w/ threads to pull the windings off. It has a tapered shaft and a small key in the shaft holding the Paw for the hand start. I took the elect. start Paw one off and put it on the Red Head engine with a couple of washers to move it out. The thicker, higher one I had to hand grind a taper the same size as the crank on the back side, take out the key and put blue thread sealer on the taper, to get it farther in the eng case to put the pull start housing on.
Buy the way, DDM has Walbro HDA-48D 19mm purge carbs onsale this week for $37.99 limit 2. I just order my second one today. Put PBP in the coupon box and save 5% or $36.09 and $3 S/H to your door, $39.09 that's a Good Deal. You need to run a modded intake manifold, or run a barb line from the cases to the carb on the red head engine. That's why it's called a Purge carb and not a pulse thru the manifold. I have a GRT 40/ CY 42 Int. Man Kit, that takes the pulse of the cases and out the bottom to a small barbed purge fitting, then a small hose to the carb. Going to mod it and put it on my Red Hot Rod Zen eng.
I took the flywheel off, cut it down, put the rocket key in and back on.
Next it goes back in the scooter, and the Pro Jet Snail exhaust back on.

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EPR

Discussion Starter · #2 · Jun 11, 2012 (Edited)

Got the engine in the scooter, started it the first time w/ no boost bottle hooked to the intake manifold. The engine was revving and the scooter clutches was engaged, tried to adj. the idle screw on the 813, then shut it down. Got the bottle hooked up, started it again still high idle w/ the screw backed out. Tried to ride it, No Go, then it stalled and started a few times and Dead Now,lol. Then the starter paw on the crank broke loose, and the Canter Head bike won't stay running, so I called it a Day,lol.
I went to a an online sight where Cam2 got reed boxes for his engines and saw the exhaust on my scooter for $135, it's for a Mini Chopper Bike w/ the 49cc piston port engine with the exh out the back side.

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SDscooters

· #3 · Jun 11, 2012

Maybe the seat post is interfering with the airflow to the engine

Hugh
SDscooters

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EPR

Discussion Starter · #4 · Jun 11, 2012

Thanks, I will have to check that,lol. I think the plug is fouled from all that car oil I put to lube the cyld at assembly, it has the China plug still or the intake manifold or carb is not working right the screws were 3 or more turns out. It's all new anythings possible. Have to fix the pull start claw before I can continue. Looks like i will have to slot the paw and use the key on the crank to paw.

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CAM2

· #5 · Jun 11, 2012

EPR said:
Thanks, I will have to check that,lol. I think the plug is fouled from all that car oil I put to lube the cyld at assembly, it has the China plug still or the intake manifold or carb is not working right the screws were 3 or more turns out. It's all new anythings possible. Have to fix the pull start claw before I can continue. Looks like i will have to slot the paw and use the key on the crank to paw.

Car oil?.....2 stroke oil works better on a two stroke...........car oil when assembling a 4 stroke...........

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EPR

Discussion Starter · #6 · Jun 12, 2012

Got it running again, the H & L screws were way out. Turned them back in and got the idle and it was running great, and it stalled again. I am going what now, I let it sit an hour, and looked at the bulb on the 813 and it's dry. So, I start pumping the bulb and no gas, Now I an getting Mad. I move the scooter and gas started leaking all over the ground. After inspection I found the black inlet line was split almost in half where it goes in the tank at the rubber grommet. Fix it tomorrow, That's why it kept leaning out cause it wasn't getting enough gas, but it was fast while it lasted,lol.

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N!pples

· #7 · Jun 13, 2012

Nice!!! I hope its screaming soon!!! What frame is that? Good luck with the fuel line...

Cheers!

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EPR

Discussion Starter · #8 · Jun 13, 2012

Got the gas line fixed today, and the kill switch wiring covered w/ shrink sleeve & shimmed the exhaust with a strip cut out of a Coke can,lol. It works so Good, its the spring held exhaust and was spitting all over at the head connection.
After I adj the H & L screws, the thing is Quick off the line, almost left my shoes behind, and it sounds Nasty. Sam, this is a SICK motor, my hats off to you. It pulls so good good off the line, the clutch shoes have been shaved alittle at the outer end to fit the bell better and have not seated fully. Even at idle you can tell its not a stock head.
Can't wait till tomorrow, so I can fine turn the 813.

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