Honda Twins banner
1 - 20 of 33 Posts

·
Registered
Joined
·
39 Posts
Discussion Starter · #1 ·
I just brought this home Friday. I cleaned the carbs and reset the floats to be level with the bottom of the carb since I had no way of measuring. The bike will start after cranking for ever but it will not idle and simply sounds very sick. I can ride around the NH but have to constantly work to throttle to keep it going. I check the plugs, they are wet and black, I don't think it's oil it seems to be gas. The cold compression is about 105 for both cylinders this is not with the throttle open. I didn't read that until today. Thoughts?
 

·
Registered
Joined
·
555 Posts
The compression readings don’t mean anything unless you have choke off & throttle open, more preferably with the carbs off completely. Cold compression doesn’t mean much either, especially given that you have fuel issues to address first. You need to get a caliper or some other way to measure carb float height - guessing at how high it is will almost certainly mean it’s off, and that’ll definitely affect that your mix is rich (given gas-wet plugs). Your local auto parts store should have digital calipers for no more than $20.
 

·
Registered
Joined
·
39 Posts
Discussion Starter · #3 ·
The compression readings don’t mean anything unless you have choke off & throttle open, more preferably with the carbs off completely. Cold compression doesn’t mean much either, especially given that you have fuel issues to address first. You need to get a caliper or some other way to measure carb float height - guessing at how high it is will almost certainly mean it’s off, and that’ll definitely affect that your mix is rich (given gas-wet plugs). Your local auto parts store should have digital calipers for no more than $20.
Ok, where do I measure from when setting the float?
 

·
Registered
Joined
·
555 Posts
If you don't have one already, download a copy of this (http://dannix.net/sites/default/fil...0_Workshop_Service_Repair_Manual_Download.pdf) - printed is nice if you can pull it off without too much trouble. That's the original CB200 service manual, it'll have the entire carb reassembly and adjustment sequence. Page 34 has the sequence - it looks like you can do it with a metric ruler accurate to millimeters, if you don't want to go as far as calipers. Gist of the factory sequence seems to be:
1) Position the carb with the main bore facing up (so with the float hinge facing up) - the float arm should just barely close the float valve without compressing the spring
2) Measure the float height from the carb body (so the mating surface with the carb bowl) to the far edge of the float - 21.0mm is the distance you want
3) Gently bend the float tang to set the measured distance to both floats to 21.0mm
-If you find that one float is higher or lower than the other, you may have to gently twist the floats to make them match.
 

·
Registered
Joined
·
555 Posts
Simo's absolutely correct - you should do a basic tune up prior to starting the bike again after the carb floats are set. If you haven't already, take a run through this checklist: http://www.hondatwins.net/forums/67...n/16105-basic-checklist-new-you-old-bike.html - it's very comprehensive. Oil change, oil screen/slinger clean of gunk, cam chain tensioned, valve/tappet clearance set, and timing set. The Factory Service Manual is the link in my last post.
 

·
Registered
Joined
·
39 Posts
Discussion Starter · #7 ·
Ok I downloaded the manual. Thanks for that, I will conduct a full tuneup and oil change this weekend and set the floats.
 

·
Premium Member
Joined
·
2,838 Posts
There have been a lot of threads from members who have "thoroughly" cleaned their carbs only to be told several times by other members the symptoms they are describing is from dirty carbs. Clogged passages need something softer than the carb body run through them so as not to deform the passage. Closed passages will not allow carb cleaner to flow through them so they remain clogged. Just something to keep in mind.
Are both plugs wet and black? I'm not sure about your bike but other twins will have running and idling problems with a weak battery/charging system.
 

·
Registered
Joined
·
39 Posts
Discussion Starter · #11 ·
That's because your floats are almost an inch out of spec
You are correct the right side was almost an inch out of spec and the left was about 1/4 out. New points and rectifier should be here today. Hopefully I can complete the rest of the tune-up this evening. What are the chances of needing a new coil? Just a thought since this thing is over 40 years old.
 

·
Registered
Joined
·
555 Posts
Dunno about the 200, but 360 coils are expensive (or slight less expensive but require modification), and are pretty obvious when they fail - they tend to be an on or off item, rather than a slow march to the grave, so if you were running already, I think they’re probably fine. I’d leave em alone.
 

·
Registered
Joined
·
4,770 Posts
The 200 coils have HT leads built in to the coil , they usually deteriorate at the point where the coil and body meet. If the. Case is bulging split or shows other obvious signs of heating or there's any continuity between the primary leads and HT leads replace it otherwise leave it be
Any 5ohm twin fire coil will work
 

·
Registered
Joined
·
39 Posts
Discussion Starter · #14 ·
I’m banging my head against the wall, I did a full tune up so I thought, now it runs the same but sounds like the valves are loose, or ticking. Will not idle and it smokes like crazy. Smells like a nasty old car, I still think it’s running rich. I put #98 in main jet to try to lean it out. I’m at a loss.
 

·
Registered
Joined
·
6,495 Posts
I’m banging my head against the wall, I did a full tune up so I thought, now it runs the same but sounds like the valves are loose, or ticking. Will not idle and it smokes like crazy. Smells like a nasty old car, I still think it’s running rich. I put #98 in main jet to try to lean it out. I’m at a loss.
I'm pretty sure that CB200 takes a #88 main jet - CL200 takes #90.
 

·
Registered
Joined
·
4,770 Posts
IF you set everything correctly and the battery's good and you've put fresh plugs in and it won't idle it's because you're carbs ain't synced or they're not clean or both.
How exactly did you set the points gap and timing and in what order and how did you set the tapits and cam chain.
The idle is governed by idle set scews on the side of the carb not by the main jets. The main jets affect the carbs at WOT (9500 rpm) not idle (1200 rpm)
 

·
Registered
Joined
·
39 Posts
Discussion Starter · #18 ·
Looks like the kit I purchased had the wrong jets in it. I am going to go through the entire procedure again today. I will also replace the jets and clean the carbs again. Hopefully it works.
 

·
Registered
Joined
·
6,495 Posts
Looks like the kit I purchased had the wrong jets in it. I am going to go through the entire procedure again today. I will also replace the jets and clean the carbs again. Hopefully it works.
Don't ever use the jets or needles from "carb kits" if the originals are still available - brass parts in the kits are junk.
 

·
Registered
Joined
·
39 Posts
Discussion Starter · #20 ·
Ok, I put the original jets back in. Set the timin, adjusted the timing, did the balances and can chain. Bike runs great from 3500 to 9000 RPMs won’t idle still. I rode it about 15 miles with my wife following she said, the pipe on the left is smoking at reflights but not while I’m going. After taking the carbs apart again I noticed that the float on the left carb is different from the right. It does not have the same shape around the pin. The circumference seems the same on the floats but definitely different. Could that be causing all my issues?
 
1 - 20 of 33 Posts
Top