Cb200 fresh rebuild horrible compression! help

Hahaha right. So good news I found another compression tester sitting around in my grandfather shed its one of the small ones with a rubber tube you just push up against the spark plug hole, the rubber is dry rotted so I couldn't get the best seal but I got about 150 psi! So I guess my other expensive tester doesn't work. So I have it all back together I got new points and condensor and it doesnt seem to be getting the best fire it will start up sometimes and rev a little them wont start again? It seems a lot of people are putting that Petronix 1847a ignition system on it with a Dyna DC1-2 coil do you think thats a good idea and will help?? Any other ignition systems out there for cb200?
 
Have you adjusted the valve clearances on the rocker arms?
Timing adjusted on the points?
Plugs and points properly gapped?
Using clean carbs, fresh gas, and a decent battery?
 
Yeah everthing was done right, its getting fire but it just doesnt seem like enough. It wil start for a min and turn off and wont start again
 
Yeah it seems like its getting a lil too much gas. But even when I shut the fuel off and clean the plugs it doesnt seem to wanna go
 
Not to be a dick but the "everything is right" thing is kinda dumb to say.....if it was true it would run....
Also stop trying to add more variables to the engine like after market ignitions before it runs right stock.

In the factory service manual they go through things to check in the order that they should be checked.
You have to start at the basics and work your way up from there
 
OK, so it appears to have enough compression by all accounts. Cheap isn't always cost effective as they say.

So that brings us to everything else. Things get lost in translation with short replies so I'll ask again just to be sure. Did YOU check the valve clearances and if so were they tight or loose or?

On the ignition system, there are a few things that could be contributing such as:
- Weak coil
- Bad plug caps
- bad plug leads from the coils
- soiled plugs
- dirty points
- rusty connectors in the main switch or the kill/run switch
- low battery voltage

I'd start with the last one first and charge up the battery. Then I'd get a few spare new spark plugs. They are cheap and once they foul it's hard to get them to work again. I'd buy a pair of new plug caps and trim 1/4" off the ends of the plug leads. Then I'd clean the points and check the voltage at the points to see if it's close to 12 or closer to 10 or 8 even with a fresh battery. That would point to crappy connections.

Once I was happy with the electrics and was getting a spark that jumps at least a 1/4" in air across a plug tester (available for about $5 at Autozone) I'd start on the carbs. Just remember that the coil is double ended and one end must be grounded when you test for sparks. If one lead is flapping about in the breeze while you test the other side, not much will happen.

Carbs need to be spotless and on those there is a tiny hole that the pilot jet mixture sprays from that clogs easily. It's about 1/2mm across so it is small but must be clean. Check for air leaks around the carb boots and between the boots and the head.

That's enough to keep you busy for a few hours. And don't eat too many Easter eggs.
 
Gotcha so I went through everything like you said and my coil is the only thing I haven't replaced so got a new one and I have great fire. So my bike runs but not very well with my old carbs on it. So im gonna grab some mikuni vm20s can you recommend jetting? My bike is bored .50 over and has short exhaust with very little baffle I also live in Fl so its 90 most of the year. On most cb200s I see people doing 135main and 17.5 pilot but it seems theyre still not running right?
 
Blindly replacing parts is a waste of time and can give a false sense of right/wrong. Ive pulled brand new parts out of the box that were inop.....

Also again you are just trying to add more and more variables.
You have not done anything to cause the bike to not be able to run on the stock carbs so why go with bigger ones?
cut exhaust is not a performance improving mod.
There is no "use these jets" kinda help when dealing with custom stuff. weather, motor, gas, parts and a million other things come into account when dealing with jets. Plan to buy atleast 3 sets of jets and changing them out a few times before they are right.

Honestly if you cant get it to run right on the stock carbs with a factory manual i cant see you being able to tune the bike with aftermarket carbs.
 
I guess i'm being to vague when I got the bike I opened up the carbs to clean them and the slides were upside down and I was told by the previous owner that he took them apart and lost something out of them, I dunno what piece it was but he was clueless to carbs anyway. I also did not cut my exhaust I bought shorty cherry bombs off dime city cycles. I understand your not gonna be spot on with jets so if you could give a me a guess than that would be nice. Other than that i'm sure you have many other forums to attend...
 
What parts do you think are missing if you just cleaned them out. Let's start there and move on one step at a time.

Once you start the bike, how does it run at idle and have you run it on the street at all? Are you snapping the throttle open or rolling it on and when does it die/bog?

And let's not forget that a CB200 doesn't make a whole lot of power on a good day.
 
i know you're excited to get this baby on the road and ride but dumping money into it blindly and not using your resources will burn you in the end. when it comes to troubleshooting it is exactly that, there are ways to diagnose a problem to make sure it is that without throwing money at random parts to swap out to see if that will fix it and it's still not running or running like shit. For the carbs go to bike bandit and search your bike and it will give you a full breakdown of the carbs so you can go through it and see whats missing, also snag a manual (clymers etc) there are a few links on here for some free Downloadable links that are in a PDF format. This is the new generation of info man abuse your privileges of the internet and search everything 99% of the stuff can be found on your own the other just ask away. you're not going to learn anything by asking just do it.
 
OK. You thought parts are missing but you don't know if they are. I follow that you are telling us what the PO told you and you don't know if it's true or all BS. Do you have any pics of the carbs either together or in bits? That might be a way to get started.

You mention that it bogs. Are you opening the throttle quickly or slowly and does it maker any difference?

We realize that you're not an old pro and that you don't know what you don't know and that's all OK. A lot of info is already out there but usually people don't know what to ask and don't know if what they are looking at is relevant or not. So let's walk through this one step at a time and see if we can collectively determine the cause and the fix.
 
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