Won't crank and won't pedal

GoldenMotor.com
M

Mkiieurojetta

New Member
Dec 10, 2013
6
0
0
north carolina
Hey guys!
This is my first post and also my first time dealing with a motorized bike. So I bought a cruiser frame from a lady. I did not ride it or anything when I bought it. I then bought a Chinese "80cc" motor kit and got every installed. Well noticed my bike crank was too narrow no matter how I mounted the motor. So I ordered a 3 piece wide crank kit along with a bent fork and crown extender. I just installed everything and tried starting it today. No start and extremely hard to pedal. The bike was a 8 speed that I took that out and made it a single speed on the smallest sprocket so it should be easy to pedal. So a friend and I started looking at different things. It got fuel but the pedaling was way to hard to do a spark test but we did hear compression. I took the cover for the magneto off and noticed the ground was hooked up to the same spot as the blue power wire. I cut the black wire and grounded it to the bolt holding in the magneto. Still no spark and hard to pedal. Checked tension and it had about 3/4 slack I. The chain so that is in line. Took the engine kill off and same problem. I noticed the back wheel wobbled pretty bad so I took a better wheel I had and put the rear sprocket on that and same problems. My friend had a spare cdi that was tested good on his bike and still nothing. I have exhausted everything I know to do besides I did not check gap on the uh and the number on the plug matched known good numbers for these motors. Plug had no carbon marks which indicates no fire and did not smell of gas. So after all of this do any of you know of anything else that can cause no spark and what can cause it to be super hard to pedal the bike? And we have adjusted the clutch to where there is no slack and she. You hold the clutch in you can roll the bike no problem and you release the clutch and the rear tire does not move when rolling it around.
 
bluegoatwoods

bluegoatwoods

Active Member
Jul 29, 2012
1,581
6
38
Central Illinois
It was kinda hard to 'get' everything that you stuffed into that one long paragraph, but I'll try. (Don't take my criticism too hard. It's just a 'heads up')

From your headline I had the impression of a seized piston. But it doesn't look like that's the case. It sounds as though you can get that piston to go up and down. Correct?

Your bike isn't heavy enough to turn over that engine if you're just walking along and pushing. A skidding rear tire/wheel is exactly what you should expect.

Have you tried just coasting down a bit of a downhill and popping the clutch? If not, then give that a try. You might as well close the choke in the hope that she starts up.
Maybe you won't need choking if you're one of the lucky few who have warm weather right now. But you probably will.

If she starts up, or just pops and sputters, then you know you've got spark and any other problems you might have are small ones that you'll be able to find and fix.

So why don't you try that experiment and let us know the results?
 
M

Mkiieurojetta

New Member
Dec 10, 2013
6
0
0
north carolina
We have tried coasting it down my driveway and cul de sac with no luck. I just took the chain off the rear sprocket and tried pedaling and it did it perfect but as soon as I put the chain back on it does the same thing over again. I am leaning on maybe a clutch issue possibly.
 
crassius

crassius

Well-Known Member
Sep 30, 2012
4,032
158
63
USA
first thing is that for easy pedaling, you want the largest sprocket at the rear
 
M

Mkiieurojetta

New Member
Dec 10, 2013
6
0
0
north carolina
Ok so still nothing. I tried adjusting everything from the clutch cable to internal clutch. Still nothing. I even took the clutch plate off and tried and it was very hard still to try and pedal. Also still have no spark. I took the chain off of the sprocket from the motor to the rear wheel again and tried pedaling without the drive chain on and it pedaled like a dream. Put the chain back on with still not clutch plate and same issue as before, very hard pedaling and no fire. I am starting to think it is a bad motor. I also made a video that I will try to post on here about the issues so you'll can see what I am talking about. Anyone have any more thoughts on what it could be? Completely taking the clutch plate off should have eliminated clutch issue as far as pedaling goes correct?
 
Last edited:
Kioshk

Kioshk

Active Member
Oct 21, 2012
1,152
10
38
Connecticut
Verify that you have a spark as prescribed repeatedly on this site, then come back. (use this site's search tool)
 
crassius

crassius

Well-Known Member
Sep 30, 2012
4,032
158
63
USA
on with still not clutch plate and same issue as before, very hard pedaling and no fire
Click to expand...
without the clutch engaged, the engine should not be turning so there can't be a spark - look for something rubbing somewhere
 
M

Mkiieurojetta

New Member
Dec 10, 2013
6
0
0
north carolina
I tested spark by having the clutch engaged and turning the crank and no fire even grounded it at the motor and nothing. The only thing I can think of is test the resistance at everything. And nothing is rubbing that would cause it to be really hard to peddle. That was my first guess when it happened.
 
GearNut

GearNut

Active Member
Aug 19, 2009
5,104
11
38
San Diego, Kaliforgnia
The engine needs to be spinning pretty fast for spark to occur. I would venture to guess of at least 200 RPM if not faster for testing purposes. Turning the crank over by hand is definitely not fast enough.

This may sound like a silly/ stupid question, but I gotta ask:
To start the engine are you pedaling the bicycle up to at least 10 MPH and then releasing the clutch while still pedaling hard or are you trying to pedal start the engine with the bicycle at a dead stop with the clutch lever released/ all the way out?
 
M

Mkiieurojetta

New Member
Dec 10, 2013
6
0
0
north carolina
That's not a stupid question. But yes I am still pedaling as hard as I can but like I said it feels as if the bike is in the highest gear possible when it is actually on the lowest setting so I do not know if it is getting up to Rpms like it should be. I need to figure out why it is so hard probably first before I can get the spark down. My friend who has a motorized bike came by to see if he could figure it out. He has no idea why it is so hard to pedal when his is not doing it. I do not see any rubbing going on or any reason for it to be doing this when the clutch is definitely is fully disengaged.
 
Kioshk

Kioshk

Active Member
Oct 21, 2012
1,152
10
38
Connecticut
It has been my experience that with the spark-plug removed (but grounded to the head) and connected to the CDI, you most certainly SHOULD be able to produce a visible spark by either rolling the bike or raising the rear-wheel and turning it by hand. Just don't expect to see it in direct sunlight.
 
F

FFV8

New Member
Oct 29, 2013
551
16
0
Spring Valley NV
I had a china girl do the same thing.

Locked up solid, even with the small gear removed from the crankshaft.

Take the 3 screws out of the sprocket cover, and remove the cover. Then try to pedal the bike.

I had to grind a lump out of the inside of that cover where the sand had collapsed when the part was cast. It was dragging on the chain.
 
maniac57

maniac57

Old, Fat, and still faster than you
Oct 8, 2011
4,484
22
0
memphis Tn
Is the chain binding under the front sprocket cover? Some kits need grinding on this cover for chain clearance. Remove it and look for marks of chain interference inside. Dremel or grind as needed.
BTW...the smaller the rear sprocket, the HARDER it is to pedal. You want it on a larger chainwheel for easier starting.
 
KCvale

KCvale

Well-Known Member
Feb 28, 2010
3,966
57
48
Phoenix,AZ
Mkiieurojetta said:
Hey guys!
Well noticed my bike crank was too narrow no matter how I mounted the motor. So I ordered a 3 piece wide crank kit
Click to expand...
These 2-stroke motors are 4.75" wide, what the heck kind of bike did you get that has narrower pedal crank arms than that as I've never seen one?


The bike was a 8 speed that I took that out and made it a single speed on the smallest sprocket so it should be easy to pedal.
Click to expand...
what is the 'that' you took out?
Don't you have any pictures?
The smaller the front pedal sprocket and larger the back the easier it is to pedal.

I took the cover for the magneto off and noticed the ground was hooked up to the same spot as the blue power wire. I cut the black wire and grounded it to the bolt holding in the magneto.
Click to expand...
What the heck engine kit exactly did you buy that had the black and blue wire connected to same spot from the factory?

Most Magnetos look like this.



Don't confuse my own red and white wires going into the engine with stock, I replace all the stock wiring on every build, but location of the connections on the coil are the same.

The coils ground at the top MUST be soldered to the metal housing or you won't have ground for the plug on the head.

The blue coil out is at the top, the white out on the bottom, just cut that useless thing off.

This mag had the ground connected on the bottom screw opposed to the top but not problem so long as the coils ground tag is properly soldered to the mag housing.

Note the new Skyhawk coils are different.



The new coils don't have a secondary white wire winding, the lower tab is ground, but just like the other ones the coil ground must be connected to metal or again no ground for the plug so hence no spark.

Pull the plug out to check for spark keeping mind the end of the plug needs to touch metal but the bike should be pretty easy to roll with no compession with the clutch out but you can check for spark voltage with an meter set to low AC range from the plug cap to ground.

Once you verify you have spark leave the plug out, turn the gas off, don't give it any throttle, and with the clutch out pedal up the road and back a couple of times to blow out any excess fuel trapped in your crankcase left by all your attempts to start it.

It's as good a place as any to start.
 
Groove

Groove

New Member
Nov 2, 2012
245
2
0
Lexington, KY
All the advice given is good. It sounds like you've exhausted many of the complex potential issues, so it's probably something simple like ensuring the proper spark plug / plug boot connection, etc.
 
2door

2door

Moderator
Staff member
Sep 15, 2008
16,302
175
63
Littleton, Colorado
The OP has never answered the question as to if he is using the clutch correctly to start the engine. Also he has not said how he has confirmed "no spark".
From the description he gives I still maintain that the clutch is not adjusted correctly and he is trying to pedal start with the clutch engaged.
Here is a great tutorial on proper clutch adjustment> http://motorbicycling.com/showthread.php?t=22726

If the chain is in fact binding at the drive sprocket inside the clutch actuator cover he would not be able to pedal at all yet he says "it is hard to pedal". Yes, it will be hard if the clutch is engaged and that is probably because the clutch cable is not adjusted/tight. Trying to pedal start an engine from a dead stop with the clutch still engaged would be very difficult and probably result in his problem to this point.

This could also be a case of stuck clutch pads but if so they are stuck harder than any I've ever encountered. By now, reading from his posts, the flower nut adjustment is way off too. That complicates things.

I'd want answers to the questions mentioned above and maybe a couple of photos of the installation before offering anymore advice.

Tom
 
Last edited:
L

lenny9651

New Member
Apr 7, 2013
59
0
0
florida
disconnect your kill switch wires from the motor and try it again, most of the times that this happens to me its a bad magneto or a bad kill switch. both are cheap to replace
 
You must log in or register to reply here.
Top Bottom