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Old 07-25-2010, 05:42 PM
joabthebugman joabthebugman is offline
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Join Date: Jun 2010
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Default First ride questions

just finished my first bike
I have one that I bought already assembled and have built one for a friend, but this is my first and I have some questions

How hard should this thing be to start
It seems that I have to be pedaling a lot harder to start this thing than i should
Sometimes I pop the clutch and nothing happens, if I keep pedaling it will try to catch and sometimes does

I have only ridden this thing to the store and around the neighborhood for less than a mile or two and the chrome muffler is almost completely discolored from the heat
Is this normal
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Old 08-19-2010, 07:26 PM
greasemonkey90 greasemonkey90 is offline
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Join Date: Aug 2010
Location: garden gove,ca
Posts: 7
Default Re: First ride questions

It shouldnt be that hard to pedal and start it.. First it helps to start the engine if you hold down the primer bulb for about 3 seconds. Get up to at least 5 mph and let out the clutch and should start up pretty quick

The discoloration on the muffler is normal
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Old 08-19-2010, 07:36 PM
Bikeguy Joe Bikeguy Joe is offline
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Default Re: First ride questions

* or 10 mph and also try using 1/2-3/4 choke.

You should look at the plug and see what it looks like, (brown to black is good, white or grey is bad)

Some discoloration is normal, but heavy discoloration can be an overly lean mixture, which can also cause hard starting. A lean condition can be caused by an air leak between the intake and the cylinder, which is not uncommon.
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Old 08-20-2010, 03:41 PM
Dougan Dougan is offline
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Join Date: Apr 2010
Location: wisconsin
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Default Re: First ride questions

pedal-starting shouldn't be hard, but you could pedal steadily at 8mph for a long time and not start it. Really, think of it more as the torque you put on the pedal than the speed. I usually get going a decent speed, and then let the left pedal get as high as possible, and then put all of my weight onto it as if I was starting a kick-start moped. This works great without a ton of force. But sitting and just dropping the clutch and pedalling normally won't get it started.
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Old 08-20-2010, 04:00 PM
Nougat Nougat is offline
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Default Re: First ride questions

I must have the easiest starting HT in history. All I do is close the choke halfway, pedal a couple times, clutch out and it's running. After it's warmed up, it restarts if I breathe on it too hard.
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Old 08-21-2010, 10:05 AM
Dougan Dougan is offline
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Location: wisconsin
Posts: 78
Default Re: First ride questions

Yeah, once mine's warmed up it starts up pretty well. I've had a few times where my clutch cable slipped a bit and the clutch would just barely engage when it was supposed to disengage and i'd have it start and stop while the clutch lever was held in!

Mine starts up a heck of a lot better with a fresh spark plug, too.
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Old 08-21-2010, 09:21 PM
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2door 2door is offline
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Default Re: First ride questions

As has been said here many times before; all of these 2 strokes are different. Some like the choke, some don't. Some like a little prime, some hate it. A few of them just want to be left alone and pedaled for a few feet and then there are those that want lots of speed to fire. You'll need to experiment with your particular engine and find out what it likes. Make sure you have no air leaks, check for a good fuel flow and that the choke plate is open fully. Play with it, experiment and eventually you'll find that 'Sweet Spot' that will give you the quickest start. Good luck, have fun.
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Old 08-23-2010, 11:21 AM
fat daddy fat daddy is offline
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Join Date: Jun 2010
Location: Wva
Posts: 26
Default Re: First ride questions

Mine didn,t start worth a crap with the carb that came with the kit,I had tried to get the fuel mixture right by adjusting the clip on the metering rod but even on the top groove it was still too rich.I bought a CNS carb and a MM aluminum intake,put them on,didn't touch the air mixture screw(it had a mark on it from wherever it came from) but did put the clip on the top groove on the metering rod,crawled on the bike and put the choke lever(actually and enricher circurt) in the halfway position,peadled about 3 rotations and it fired right up.I was happy.
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Old 08-23-2010, 12:28 PM
KCvale KCvale is offline
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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.
KC's Krusiers Builds
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