Help! Building a Clairmont 80cc, won't start

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BTR

New Member
Jan 15, 2012
10
0
0
Bakersfield
I started building a Schwinn Clairmont 80cc bike a few weeks ago. I got the engine set up, but it won't start. Every time I ride it, it gives a little put and then dies, but the throttle doesn't engage and the bike goes nowhere. It's not a real expensive kit, but I'm thinking about investing in a new carbeurator and CDI. If I can I'll get a picture or a video up soon so you can see. But any ideas what the problem might be? Help, I'd really like to get out and ride this bad boy.
 

rustycase

Gutter Rider
May 26, 2011
2,746
5
0
Left coast
Not really a lot of info, BTR, but if u got it to pop, perhaps just a bit more pedaling and she'll take off???

My own mab starts best when I give it no throttle at all, then ease the throttle on a bit, here and there. ...and this is all from cold, in abt a 100ft. I got no choke installed.

Alf and some of the other fellows have some real good diagnostic threads you might wish to look at... fuel, spark, and compression are the first 3 to look at.
disconnect the kill switch til u get it running. they can create problems.

Probably no need to buy new parts just yet.

Best
rc
 

takeitez

New Member
Dec 19, 2011
139
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0
Clayton Missouri
Forgive me if I am insulting you but you are you keepin the choke on to long? I know when I started I had no idea what those crazy chinese symbols were tryin to tell me and took be about 30 min to figure it all out. The second thing is to check plug wire. Make sure it is "screwed" in all the way. In my experience if you are having a real little "put put" at the beginning that is what has been the problem. I have also found the stock carbs are just fine but the cdi/plug wire is junk. I doubt it is already broken but will probable need a replacement after 10-100 miles.

Good luck and welcome to the hobby.
 

BTR

New Member
Jan 15, 2012
10
0
0
Bakersfield
Yeah sorry, I'm still new to this, and don't worry, it's not insulting, I'm a noob, I know it. I'll try what you guys said, and yeah, those symbols are still confusing me. i'll give it a shot and let you know how it works out, i'll try and give you some more details soon.
thanks for the help. Just out of curiosity, what kind of bike do you use and engine do you use?
 

takeitez

New Member
Dec 19, 2011
139
0
0
Clayton Missouri
I am on a trek 850 with a dax f50 engine. Just so you know on all the stock carbs I have seen are set up so that to choke it, you pull it up and then when it has started or it wont start try and turn it down. You can also try starting it up with half choke and stuff like that. It really just depends on what your little engine wants and the temperature.

What is our premix ratio? A lot of people hear you need to do 16:1 and that can make your engine run a little lean. I have done 20:1 but I hear about people doing any where from 24:1-32:1.
 

BTR

New Member
Jan 15, 2012
10
0
0
Bakersfield
The Premix ratio is like 12:1, If 16 is lean, then 12 must be anorexic. I just rode it today, I fixed the wiring problem. It ran for about 30 seconds before it quit. If the mixture wasn't as rich, what kinds of problems would there be?
 

bluenosegoat

New Member
Dec 29, 2009
259
0
0
arizona
12-1 is WAY to much oil. 16-1 is still to much. Try 24-1 for break in then 32-1 after the first couple tanks. Personally I run 32-1 Lucas semi synthetic, even for break in. I think you'll find many here will agree with me with on the mix ratios for a "normal" 2 stroke oil.
Sounds like you might be confused with the mix ratios. 32-1 is leaner (less oil) than 24-1. So at 12-1 you are way to rich (to much oil) so much so that there is just not enough fuel to ignite.

I had a customer who mixed his fuel in his tank and put the oil in first then the gas. All the oil settled in the carb float bowl and of course the engine would not fire-they wont run on oil alone. Just saying.
 
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BTR

New Member
Jan 15, 2012
10
0
0
Bakersfield
Ok, then my fuel ratio isn't what I thought it was, I have a 6oz bottle of oil with a 1.5 gallon tank. Maybe I'm just doing my math wrong. But, I got the bike to run, I got a good ride out of it, the clutch seized up when I tried to stop for a stop sign, now when I pull the clutch it does nothing, the chain doesn't move. the bike rode, but the second I tried to idle, it died. If I'm sitting in idle, should I engage, or disengage the choke?
 

BTR

New Member
Jan 15, 2012
10
0
0
Bakersfield
Also, Thank you, all of you, I don't know if I could have figured this thing out to get that five minute ride. It was awesome. Thank you for your help with this guys!
 

\./

Active Member
Dec 4, 2011
399
37
28
CA
if u have a hard time idleing it, mess with the carb idle screw OR the clutch. take it apart and losen it a bit.
 

takeitez

New Member
Dec 19, 2011
139
0
0
Clayton Missouri
See that little screw on the side of your carb? Turn it all the way in and when you pull the choke you will hear you engine keep going even when you are not giving it any gas. Turn in back out very slowly until it dies. After It dies turn it back in about half a turn and you should be good more or less.

This is just what I do if there is a better way to set the idle or if there is something wrong with the way above some one please correct me.
 

Blake84

New Member
Jul 15, 2011
136
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39
miracle mile los angeles
I just did my first build and had similar problems.

I took the carb apart and my float had gasoline filled up in it. apparently when i got kit it had a small hole they are plastic pieces of sh*t so my engine would start up ride and then flood.

I replaced the float all good now.

i was told to screw the screw on the carb all the way in and then loosen 1 and a half rotations. then try riding and each time unscrew half a rotation until it rides good.

im a huge noob probably not good with advice im just letting you know what just happened to me on getting my first bike started
 

bluenosegoat

New Member
Dec 29, 2009
259
0
0
arizona
Ok, then my fuel ratio isn't what I thought it was, I have a 6oz bottle of oil with a 1.5 gallon tank. Maybe I'm just doing my math wrong. But, I got the bike to run, I got a good ride out of it, the clutch seized up when I tried to stop for a stop sign, now when I pull the clutch it does nothing, the chain doesn't move. the bike rode, but the second I tried to idle, it died. If I'm sitting in idle, should I engage, or disengage the choke?
First thing is everything you are looking for is in this forum if you search for it. You will learn a lot of great info if you just look for it but......

The bottle of oil you have hopefully has a mix chart on it to follow? I know the oil I use for a 32-1 mix is 4 oz to a gallon but oils vary especially with some of the synthetics.
Once you have the bike running for a minute or two you should not have to mess with the choke at all- its only for cold starts. Here in Az I might use my choke once or twice a year!
I'm not understanding your clutch issues. What i tell people is with the lever released (as if you were riding under power engine engaged) go to the clutch arm where the cable is attached. Loosen the lock on the cable and just using you hands pull the cable tight and snug up the lock to the arm and tighten it down. This is usually a good starting point. There should not be much if any tension on the clutch arm with the lever on the handle bars released.
Hope this helps and don't be afraid to use the search feature of the forum. Good luck!
 
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BTR

New Member
Jan 15, 2012
10
0
0
Bakersfield
I actually got it up and running today, the bike is pretty much fully functional, it's still being broken in obviously and there are a few kinks here and there to work out, but the issue wasn't the clutch, my chain tensioner loosened and the chain got stuck, I had to tweak it out, fix the tensioner, and I was golden. Yeah, I just didn't have my numbers right on the premix ratio. It rides great.
 

rustycase

Gutter Rider
May 26, 2011
2,746
5
0
Left coast
Whew!

lol

Glad to see that mathematics thing got worked out! lol

16 or 12:1 WoW!

...I mean, I've probably done that at some time or other, in the past, on some old motor, when there was nothing else available and I needed to get a task done...
But Gosh! That's an awful lot of oil! lol

Guaranteed to foul the plug!

and I probably did it with 30wt motor oil ! lol

There's tons of opinions here in the mix oil threads to review so you can decide which camp you wish to side with....

I'd like to try the Opti2 at 100:1 next time I experiment with mix oils.

In my present (well run-in) 2 smoke engines I'm running from 3 to 4 ounces per gallon of unleaded Kalifornia gas. They are all hangin' in there... No great performance, but no fouled plugs, either.

Glad you are having fun with the new mab!
You should have most your bugs ironed out in time for lots of good riding this spring and summer!
Best
rc