wont start

GoldenMotor.com

Bikeryhder

New Member
Jul 2, 2015
4
0
0
Jefferson city
ok so i bought the kit to make a motorized bike. got it together and it wont start. at first the back tire wouldnt spin and i read on here to sit on it and push backwards and it free it up. now iy wont start. i checked the spark and i did not see anything. also when i pulled the clutch in it seems to do nothing. please help for the seller knows nothing.
 

Davezilla

New Member
Mar 15, 2014
2,705
10
0
San Antonio Texas
If you have no spark check that you got everything wired correctly with the black to black and blue to blue, the white wire should be capped off so it can't short to ground or to the blue wire.
If this is all ok then unplug the blue and black wires and measure the resistance of the mag coil, you should read around 350 ohms across the blue and black wires coming out of the engine, if not then pull the magneto cover and make sure the other end of the black wire is securely grounded and make sure the wires aren't broken or that the blue or the white wires are shorted to ground, the blue and the white wire can not touch the engine or the frame or they will short out.
if all this checks ok then it could be a bad cdi unit. The spark plug boot is another common problem area as it can break easily on the inside, most of us just use a regular automotive boot and terminal then screw the little metal cap on top of the spark plug so the wire will snap onto the plug. The factory plug boot has a poor contact to the plug as it is.
One more thing to check is your plug gap, if it's too big it won't fire, or won't fire strong enough to light the fuel. The plug can also become oil fouled preventing it from firing, or the gap could be shorted to the ground electrode if the plug was dropped or the piston hit the end of the plug for any reason. Set your plug gap to .024" to .028", these ignitions aren't very strong so closing the gap down to .024" can help. The factory plugs are also pretty much junk so using an NGK plug is recommended for reliability. I zalso use Autolite #275 plugs on my new engines and during tuning since they're cheap but reliable. There's no need for an expensive iridium plug on these engines, but you can use a platinum plug for more reliability and longer life after all tuning is done. The iridium plugs will work and last a really long time but will not give any performance gains contrary to what the guys selling them like to say...

Right now some other members have been noticing that there have been a lot of cdi failures recently so it is very possible your kit came with a defective one, these tend to not fire unless the engine is spinning really fast, so you may try just swapping out the cdi u it for another one and seeing if it'll start. If there is a bad batch of the new cdi units causing the engine not to start, you could get a screaming roo unit for around $20 and problem solved, there are other aftermarket cdi units but the screaming roo unit is both reliable and inexpensive, you can get one of these from pedalchopper.com or crmachine.com if this is the problem. They also make a matching mag coil if this is what's not working but so far the factory mag coils have been good for the most part. There are other aftermarket cdi units out there that are far more reliable than the stock unit but they all cost considerably more.
One more thing to consider is your fuel mix, 16:1 is way too much oil, even for break in. It's been proven perfectly safe to run 24:1 or even 32:1 during break in, the 16:1 mix could be oil fouling the plug stopping it from firing.
 

Bikeryhder

New Member
Jul 2, 2015
4
0
0
Jefferson city
thank you very much. im going to check everything tomorrow and i work at a auto part store and will gradb a new wire tomorrow. i also will go ahead and buy a cdi. thanks for the sites to buy a good one. i cant wait to ride
 

Slogger

Member
Sep 8, 2014
544
4
18
nohio
That's a terrific writeup Dave. It should be a sticky for newbs.
I would add that the clutch problem might be a cable with too much slack.
The cable should only have a bit of freeplay, too much and it won't disengage right or at all.
 

Slogger

Member
Sep 8, 2014
544
4
18
nohio
Check the chain under the sprocket cover, maybe it's hung up.

I've read the plate can somehow get stuck due to stale old chinese grease on the clutch shaft or something like that.. Maybe it's fine. What exactly is it doing that's wrong?
 
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Daement

New Member
Feb 19, 2013
11
0
1
Charlottesville, VA
I would suggest also checking the magneto coil, check that the wires are soldered on good. Moisture in the coil can cause it to not spark also. I have had this problem twice, dousing the coil with wd-40 and letting it displace the moisture for a few hours has resolved this issue for me.

And as suggested above, under the clutch shaft there is a pin in the center of the little sprocket, pull it out (and the ball bearing behind it if possible) clean out the old grease (with a q-tip etc) and put a dab of high temp bearing grease in there. A new clutch can be a bit stiff but should break in pretty quickly. Another thing you might wanna do when the clutch smooths out is add a spring like pictured below. It helps to ensure it will pop when requested.
 
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