'75 CB200 engine spins backwards during ignition -- won't start + video.

tnahvu

tnahvu

Vrooom!!
Hey all,

Got another problem. This is post upgrading to new Pertronix electronic ignition system + Dyna DC1-2 coil. Was trying to start the engine to set timing but can't even get engine to start. The starter motor spins the motor but then spins backward and make a scary "clank" sound when a slight tap of the throttle.

Anyone know what's going on here? I loosened the cam-chain tensioning bolt to tighten the chain per the manual's instruction somewhere along the whole operation; could that be the problem?

I also took out the clutch cover to replace new gasket and clean the centrifugal oil filter. that's it! COuld it be a transmission problem?

I have good sparks, compression (with the thumb over the hole test), fuel flow, jets cleaned and carbs were untouched. Starter engine spins fine without chain. Engine seems to be fine when rotating manually by hand, like when you do your timing. Exhaust blows out mist -- fuel, im guessing, doesn't smell like "pure" petro though, so carbs must be blowing in fuel/air.

Here it is VIDEO

Thanks for any suggestions

....I just to ride before it's too cold! :(
 
Re: '75 CB200 engine spins backwards during ignition -- won't start.

Not sure about the "engine spinning backwards" thing, but make sure you have the coils hooked up correctly and they aren't switched from left to right. I just did that same thing with my bike.
 
Re: '75 CB200 engine spins backwards during ignition -- won't start.

Problem still persists, especially when choke is pulled.

Could it be the cam chain tensioner? How do i check if it is? I loosened the bolt and nut but tightened them back.

Argh!
 
The engine is spinning forwards not backwards. It's a trick of the camera frame rate.

It's not the cam chain tensioner either.

Why is the whole side cover off? Did you have a problem with the screws holding the small round cover? I'd get that alternator stator and side cover back together and on the motor ASAP and remove just the round cover.

Remove both plugs and insert them into their plug caps and lay them on the cylinder head and let us know if they spark consistently and with a nice blue spark.
 
Three things every internal combustion engine MUST have; feul, spark, and timing. You have yourself going down the right path. You said there is spark, and feul. Did you install your new ignition correctly? How about the coils? Are the plug wires connected to the right plugs? What happens when you try to kick it over? What I see in the video is your engine firing at the wrong time.
 
IIRC, the cb200 uses a dual output coil. So no switching wires.

Go to Autozone or Advanced and get a compression tester. They usually have a tool loaner program. The thumb over the plug hole test just tells you that a piston is moving around......
 
'75 CB200 engine spins backwards during ignition -- won't start + video.

Spark plug: i've taken both plugs out to visual check and recheck for spark. Both have nice blue sparks.

Engine spins: It's no camera trick, unfortunately, :(, the backward motion is accompanied by a metal "clank"--don't know if u can hear it in the video. it looks like that to the naked eyes also.

Compression: It was running fine before the coil, ignition installation, and gasket replacement. so i don't think it's compression, plus, a mechanic had tested it a few months back it was good--so he said.

kick start: same thing without the metal "clank". my right leg is in serious pain after yesterday!

can screwed up timing cause the "clank"? i'm trying to start it to set timing at full advance.

thanks for tips everyone. anything else you guys can think of?
 
I dont care what kind of ignition system it is. You have more than one cylinder. The plugs for each cylinder fire at different times. If you have plugs wires swapped, the plugs will not fire at the right time no matter what you do. The answer has been right in front of you. It's timing!!! The reason your engine "runs backward" is more than likely because one or both cylinders are firing on the upstroke. this is pushing the piston back in the wrong direction for that brief moment, and causing the starter to make that sound. The fact that, as you say, it is worse when you choke the engine only makes me sure thats your problem.
When you installed the new system, you should have been following the timing marks to be at least ballpark close in timing. You should have been atleast able to start the engine. Did you mark where you were timed with the old points?
Go back to the installation instructions and start over is my best advise.
 
sallgoodguy said:
I dont care what kind of ignition system it is. You have more than one cylinder. The plugs for each cylinder fire at different times. If you have plugs wires swapped, the plugs will not fire at the right time no matter what you do. The answer has been right in front of you. It's timing!!! The reason your engine "runs backward" is more than likely because one or both cylinders are firing on the upstroke. this is pushing the piston back in the wrong direction for that brief moment, and causing the starter to make that sound. The fact that, as you say, it is worse when you choke the engine only makes me sure thats your problem.
When you installed the new system, you should have been following the timing marks to be at least ballpark close in timing. You should have been atleast able to start the engine. Did you mark where you were timed with the old points?
Go back to the installation instructions and start over is my best advise.
Click to expand...

Not true. The CB200 is a 360° ignition with a wasted spark. One coil, one point, two plugs.
 
woops! yadda yadda dual output. ok ok so the plugs both fire at the same time.... ok ok. But it's still timing, and your timing is way off.
 
No worries fellas - The small Hondas are all like that.


I thought I hit reply but must have missed it. I could be wrong, but an electrical starter shouldn't be able to spin in reverse (in less you you spin it by hand). The electricity makes it spin the correct way. And being that's the only thing driving the motor in the video, if it IS spinning backwards I would be worried. Check the timing - I mean REALLY check it. Make sure the spark is firing at TDC. Something tells me your cam chain might have jumped a tooth.
 
OK so we are all back on the same page on the single coil. Good. That was all covered on the last page. You in the back. Put down that cell phone and pay attention. :-)

We have a strong spark. Good.

That motor is NOT running backwards. The electric starter cannot run backwards and there is no way a 4 stroke can run backwards. The clank is the starter clutch skipping a beat either because the thing fired once or it's slipping from time to time.

It can fire backwards but not run. That would happen if the ignition timing was too advanced.

Let's go back to that comment about the tensioner again. It is possible that the cam chain jumped a sprocket when you were doing something there. Remove all 4 valve inspection caps and at TDC, one cylinder should have both valves slightly open and the other one should have them both fully closed. Is that the case on your motor at TDC?

If that's OK, it's either ignition timing or fuel and the ignition system is what changed, so let's focus on that. Do you still have the points and condenser etc? I'd be tempted to re-fit them just to see if it runs. but after you confirm that the cam timing is still OK.

And I don't remember if you still have the mechanical advance-retard mechanism fitted under the new ignition.
 
I'm not saying the starter or motor run backwards. I'm saying that the engine is firing on the piston upstroke, wether its compression or exhaust. Thats at least stopping the pistons correct momentum. The sound is the starter taking the sharp end of the stick.

isnt there a mark on the cam gear that you would line up with a mark on the crank shaft for TDC if you were replacing a cam chain? I would think that the cam chain would have to be very loose to jump, but I wouldnt rule anything out since I dont think we have enuff info at this point.

I agree with going back to step 1, if he even made a reference mark for the original timing. You cant just take all the points and assorted goodies out and slap in the new electronics and expect it to just run. It's not plug and play. But we dont know how he installed it. More info needed.
 
I thought I hit reply but must have missed it. I could be wrong, but an electrical starter shouldn't be able to spin in reverse (in less you you spin it by hand). The electricity makes it spin the correct way. And being that's the only thing driving the motor in the video, if it IS spinning backwards I would be worried. Check the timing - I mean REALLY check it. Make sure the spark is firing at TDC. Something tells me your cam chain might have jumped a tooth.


reverse wire it and it will!!
 
Sallgood, i agree totally.

It was the OP who is convinced that it ran backwards and that's who that comment was directed towards. We don't know what the OP doesn't know or what he did, and that's what we are both trying to address. Going back to basics.

I think we are all on the same page. The OP has mentioned that cam chain tensioner several times and that suggests that we should perhaps see if all is well in cam timing and then we can move on to ignition timing.

:-)
 
Ive also encountered this when I had a motor that was timed correctly, then I left the tensioner bolt loose and ran the engine and the chain jumped...


I would try to disconnect the starters chain, and try to kickstart the bike. If it happens again, it is probably the timing.


I ended up replacing the chain, and a size by side comparison showed that the old one was infact a bit longer than the replacement. So the worn chain could also be causing you some issue.
 
There is an old myth that came from car guys that says that to adjust a timing chain, loosen the adjuster and run the engine until it goes quiet.

Many cars and a few bikes use a similar arrangement where there is a wedge which acts like a ratchet in as much as it can move in but not out. So that type of design will work OK with the loosen and run it technique.

CB160/175/200 has a simple spring loaded plunger/tensioner and when you loosen the lock bolt, that tensioner can move in either direction. With a long timing chain that whips all over the place, the chain is very likely to jump the sprocket.

Given that our intrepid owner did try to adjust the cam chain with the motor running, it does seem like a good place to start checking. I provided a quick and dirty technique but he cam also pop the top cover off and check the timing lines on the cam sprocket.
 
'75 CB200 engine spins backwards during ignition -- won't start + video.

thanks for all the comments.

the mark on backing plate lined up perfectly with the mark on the ignition housing pre-installation. however, i know that i have to set my timing at full advance with the new pertronix unit, so i can't go back to lining the backing plate mark w/ the housing mark.

and to my naked, untrained eyes, it looked backwards. maybe "backwards" should have been used. and no, of course i didn't expect this to be plug and play. i'm learning.

will recheck timing again for sure.

many thanks for all the tips, guys.
 
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