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Motorized Cruiser Bicycles The beach cruiser has always been great bicycles to motorize. They just look good with a motor. Use this section to share and discuss about motorizing this classic.

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Old 09-06-2011, 11:04 PM
Hacksawdecap's Avatar
Hacksawdecap Hacksawdecap is offline
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Join Date: Jul 2011
Location: Phoenix
Posts: 52
Default Do I have performance issues or do i just expect to much?

Hey there I have a cranny with a skyhawk GT2 (I believe) It's 48ccs and I do have the "new" performance carb with the red filter on it. I don't have any bogging issues I fixed that by taking off the black vent tube and It really put new life in it. I don't really know the max speed I can go because I don't have any way to gauge the speed but I believe it should performing better. It seems like it can do about 25mph. Am I expecting to much out of my bike or am I experiencing Issues. Any ideas on how to tweak the carb by missing around the idle and mixture screws...or whatever. It has plenty of fuel.

I could just be tripping and lost that first month of like "wow this is fast" feeling.
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Old 09-06-2011, 11:23 PM
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retromike3 retromike3 is offline
Motorized Bicycle Elite Member
Join Date: Jan 2009
Location: Beaverton OR
Posts: 148
Default Re: Do I have performance issues or do i just expect to much?

I think that you are dealing with the limitations of the engine set up and the gearing. One thing you might try is looking at a "tuned "pipe. It effectively doubled my horsepower, But it set it up so that the power curve was a lot steeper.

Something else you might look at is the rear cog. I went with a 36 tooth. It requires more pedaling but it goes faster.

I went with a higher pressure tires with a smaller diameter cross section. Lower rolling resistance and less mass to get moving.

Lastly what I did was to try to get the body position lower and more like a road bike. The biggest amount of power once you get above 15 mph is the air drag. I dropped my handle bars by three inches and gained five miles an hour.

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Old 09-07-2011, 06:31 PM
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Greg58 Greg58 is offline
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Join Date: May 2011
Location: Newnan,Georgia U.S.A.
Posts: 2,620
Default Re: Do I have performance issues or do i just expect to much?

I have a 48cc grubee angle fire with only slight mods. and get 31 to 32 on flats,with the stock 44 tooth sprocket. The only mods are cleaning up the intake and exhaust and matched them to the ports, sbp air filter and the muffler end cap extra exhaust tube. Main jet drilled to a #64. On mine the mid range is very good, when we ride as a group when climbing hill I can pull out and pass two others I ride with even though I out weigh both.
Your results may not be the same,Greg
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Old 09-07-2011, 08:14 PM
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2door 2door is offline
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Join Date: Sep 2008
Location: Littleton, Colorado
Posts: 16,222
Default Re: Do I have performance issues or do i just expect to much?

You didn't say how much time the engine has on it but keep in mind that they perform better and better as they accrue miles. A couple of tanks just won't cut it. A few gallons and you might/probably will see a performance increase. The piston rings begin to seat with the cylinder walls, the rest of the moving parts start to wear in and things will run and feel better as you ride.
Good luck, ride safe, have fun.
Age and Treachery Will Always Triumph
Over Youth and Skill & "Charlie Don't Ride"
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