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Old 08-23-2010, 12:28 PM
KCvale KCvale is offline
Motorized Bicycle Elite Member
Join Date: Feb 2010
Location: Phoenix,AZ
Posts: 3,552
Default Re: First ride questions

I have only motorized half a dozen bikes, but with each one and of course my my ride, I keep trying new things and looking at the results.

Out here in the desert cold is not a factor, it is never even cool in the summer, so with winter around the corner for cold states this may not apply, but for me only a couple of things make the difference in how well a motor starts and runs.

You don't mention the motor or the bike with your question Joab.
People can take blind stabs at potential answers, but like mine below they are simple guess as we have no real facts about the actual bike build like type of bike and motor and it's size.

For starters I have always Grubee motors never had to mess with any carb setting other than my first build when I neglected to tighten the carbs float bowl screws and it worked it way loose riding to point of almost falling off and losing the float bowl lever pin.
I just made from a paper clip ;-}

It has all been about spark plug/wiring, and bike gearing.

If you have a typical coaster bike it has an 18 tooth rear sprocket, and if it is a 66cc motor that gear ratio is going to make it hard to start until you get up to good speed, 12 or better, and it won't even run less than that with a direct drive chain.
If you want to run slow use a geared bike and a jackshaft.

To make the starting easier either make the front pedal sprocket smaller, or the rear sprocket bigger.
I have extra chain and have no problem just putting a 20 tooth on a coaster bike and adjusting the chain.
I have actually gotten pretty go at it and never use a tensioner on the drive chain.

Then there is the spark plug.

Other than wiring improvements I have been discouraged from linking it help posts like this here, just simply using a good one and gaping your plug properly makes a world of difference.

You can get a Disc Gaper for about a buck at any automotive store.
Gap your plug to .028

I go into extensive detail about the various plug types and how they perform here if want to read up on plugs, all I can say is with these engines it don't matter what you do with the fuel intake system, if it doesn't ignite properly you are just spinning your wheels.

My 3-speed jackshaft bike starts on the second pedal at 4 MPH in 1st gear with 1/4 choke, which I turn off in 1/2 a block, and on the first pedal with no choke warmed up, like at a light.

Real info on your build would help, but that is my blind stab at it.
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