Kickstart/decompression binding

I have an 83 xr200r that I have been rebuilding.  I buttoned up the engine and was able to kick it over (not ready to start yet).  I installed the decompression cable, and it feels like something is binding. Midway through the kick stroke, there is a "click" and it is difficult to kick over (but possible).  When the kickstarter "clicks" it will not snap bak to its resting position.

 

This problem only happened when I installed the decompression cable. Could it simply be out of adjustment?

No replies................???  Without going into detail yes, the k/s lever will stick part way down...........happens when the piston is coming up on compression.  (I always find this position when checking or filling with oil to keep the lever out of the way.)  Just push it down a tad farther and it will return normally.  You'll hear a clicking noises, and yes it will be harder to kick over in the lower part of the stroke. Always return lever to top of travel and push down till k/s gears just engage, then  kick and decompressor will do it's job. :thumbsup: As for adjustment.......just like the manual says, making sure you are at TDC on compression.

 

Old School Al

No replies................???  Without going into detail yes, the k/s lever will stick part way down...........happens when the piston is coming up on compression.  (I always find this position when checking or filling with oil to keep the lever out of the way.)  Just push it down a tad farther and it will return normally.  You'll hear a clicking noises, and yes it will be harder to kick over in the lower part of the stroke. Always return lever to top of travel and push down till k/s gears just engage, then  kick and decompressor will do it's job. :thumbsup: As for adjustment.......just like the manual says, making sure you are at TDC on compression.

 

Old School Al

I had been searching the manual for any ref. about the decompression cable... but making sure the engine is at tdc is something I most likely overlooked.

After playing around with it for 15 or so minutes it seems that I don't have the cable routed correctly, (goes over exhaust and gets clipped on to the cable stay on the frame).  When the cable was tighter, the ks would occasionally slip.  The decompression would release mid stroke and then the ks would bind. Any further travel would make the ks abruptly slip.  When loose, the ks slipped very rarely, if at all.

 

When the spark plug is out and there is no cable, there is no slip/ other problems.

 

I am thinking the cable adjustment (set at tdc) and cable routing are my only problems here.  The slipping could be caused by too much tension on the cable?

Sounds like it's working correctly. The decompression lever opens the exhaust valve so when the piston is moving upwards air passes the valve allowing enough momentum that when the kick-starter is half way through it's stroke the decompression releases and several full compression cycles are completed.

 

Big bore bikes have "the drill" (not saying 200 is a big bore, but bear with me).

Push the kick start lever down slowly until the deompression lever releases and the piston reaches near TDC on the compression stroke.

Release the kick lever.

Now kick like an angry mule.

Ta-da! Starts every time and you don't need to weigh 400lbs nor use every ounce of your being to get the bike started.

 

Apply the same routine to your bike and you'll not have to worry about the kick-start decompression releasing 1/2 way through "the drill".

From what you're describing it almost sounds like you may have a problem with damaged K/S pawl teeth slipping.  The reason it doesn't slip with the plug out is because there is no load on it.  Running without a decompressor, high compression, increased displacement, or even not letting the lever return to the top when starting can damage these parts.  As well as starting like you were killing snakes......!  On these don't kick like a "angry mule".......that's for the big bore machines with heavier K/S gears. ;)    Also cable goes behind behind the pipe.

 

Old School Al

Edited by Old School Al

From what you're describing it almost sounds like you may have a problem with damaged K/S pawl teeth slipping.  The reason it doesn't slip with the plug out is because there is no load on it.  Running without a decompressor, high compression, increased displacement, or even not letting the lever return to the top when starting can damage these parts.  As well as starting like you were killing snakes......!  On these don't kick like a "angry mule".......that's for the big bore machines with heavier K/S gears. ;)    Also cable goes behind behind the pipe.

 

Old School Al

I think I may try and post a video up if I cant get the problem sorted out.  I have never had the bike running, and I replaced the ks shaft as well as some other gears. Whenever I have been "kicking" it, I am just using my hands and body weight, no violent kicks

I am going to work on the bike tomorrow (its about an hour away). It is impossible to tell from the manual if the cable mounts in front of, or behind the exhaust pipe.  As Old School Al said above, the cable is behind the pipe, however I cannot see the cable routed there, as the lack of heat shield would melt it. Also when the cable is in front of the pipe, it doesnt bind.

 

When the cable is tight, it slips. If the cable has a lot of bends in it, the cable gets tighter, and it slips.There are very few good, clear pictures of the right side of the bike. If you have a picture, or could take one, it would be greatly appreciated.

 

Any ideas? This damn bike is fighting me tooth and nail on the assembly.

Edited by dryvr12

I am going to work on the bike tomorrow (its about an hour away). It is impossible to tell from the manual if the cable mounts in front of, or behind the exhaust pipe.  As Old School Al said above, the cable is behind the pipe, however I cannot see the cable routed there, as the lack of heat shield would melt it. Also when the cable is in front of the pipe, it doesnt bind.

 

When the cable is tight, it slips. If the cable has a lot of bends in it, the cable gets tighter, and it slips.There are very few good, clear pictures of the right side of the bike. If you have a picture, or could take one, it would be greatly appreciated.

 

Any ideas? This damn bike is fighting me tooth and nail on the assembly.

 

 

I had the later model XR200R on the brain and neglected to notice you clearly stated "83"....!        :facepalm: ..........the perfect new emoticon for me! 

 

81 - 83 route the cable outside the pipe, and retain the cable with a clip on the top rear motor mount bolt.  86 - 02 route the cable under the pipe, and use a wire loop off the heat shield to hold the cable away from the pipe. 

 

Old School Al

Edited by Old School Al

I had the later model XR200R on the brain and neglected to notice you clearly stated "83"....!        :facepalm: ..........the perfect new emoticon for me! 

 

81 - 83 route the cable outside the pipe, and retain the cable with a clip on the top rear motor mount bolt.  86 - 02 route the cable under the pipe, and use a wire loop off the heat shield to hold the cable away from the pipe. 

 

Old School Al

Ah, that makes sense! I guess I will fiddle with it until it seems right.  I just can't imagine that the decompression cable, such an important part, would be so finicky to adjust.

It shouldn't be finicky to adjust.  Make sure the cable is clean and lubed, make sure crankshaft at TDC on compression..........then adjust cable to get 1-2mm of free play at cyl head lever tip. :thumbsup:

 

Old School Al

Edited by Old School Al

Well I got her running. It seems when I kick down on the kickstarter, she kicks back up. Should the decompression cable prevent this? Maybe I did not let the k/s go 'all the way up' so that the decompression could activate for the next stroke?

Edited by dryvr12

Like violently kicks back? Or just lots of resistance?

Violent kick-back is a sign of severely advanced timing and could break your leg as well as anything else that's between the connecting rod and your foot.

Lots of resistance for the first 1/2 of the kick stroke means your decomp isn't engaging.

Like violently kicks back? Or just lots of resistance?

Violent kick-back is a sign of severely advanced timing and could break your leg as well as anything else that's between the connecting rod and your foot.

Lots of resistance for the first 1/2 of the kick stroke means your decomp isn't engaging.

 

Pretty violent. If you kick at the wrong time, it will push your foot up. Hurts like a mofo. Ive only had it idle, but it starts up and runs perfectly- starts on the first kick. I didn't hear any pinging, but I was not on the gas much.

 

It does not kick back all the time, only once or twice.

But I will check timing with a light now that it runs.

I also had the throttle cracked, which could be a part of it.

Edited by dryvr12

Well, kick faster, it'll make the motor more likely to be slowing down as the piston approaches TDC when the plug fires and thus is more likely to be over "the hump" when the flame front hits the piston.

 

Throttle cracked is usually not a good idea, but we all do it.

 

Be careful, I've been thrown off the bike with an overly advanced engine kick-back. Was walking funny for a while. I'd be inclined to turn the stator back a few degrees to be safe.

Well, kick faster, it'll make the motor more likely to be slowing down as the piston approaches TDC when the plug fires and thus is more likely to be over "the hump" when the flame front hits the piston.

 

Throttle cracked is usually not a good idea, but we all do it.

 

Be careful, I've been thrown off the bike with an overly advanced engine kick-back. Was walking funny for a while. I'd be inclined to turn the stator back a few degrees to be safe.

I found a technique for kickstarting big bore/high compression bikes. It seems even brand new if kicked incorrectly, bikes can kick back up. I will have to keep in mind to put my hand on the handle bar, and not on the throttle. I agree, a few degrees retarded is worth more than a chewed up engine or broken bones!

I've owned 500cc British singles which didn't have auto decomp systems, you did it all manually.  Basically pressure on the kicker will not get a big single thru the compression stroke, but if you start at TDC compression with a strong kick you will get the crank spinning fast enough for the flywheel mass to carry thru the next compression stoke. 

That is the basis for the auto compression release on the XR200s; it lifts the exhaust valve until the kicker is horizaontal, then releases. If you start with the kicker at the top and push strongly you will have at least 1 1/2 crank revolutions to get the crank spinning fast enough to carry thru the compression stroke. 

 

DO NOT jab at the kicker like you learned on 2Ts, bring the kicker all the way to the top and use a strong smooth kick. 

 

Be forwarned: If the timing is off you can suffer severe foot/leg injuries.  I have a friend who punture wounded his calf, and a trip to Emergency, from kicking a British 500 single.  I severely  bruised the bones in my foot when a Husky 400 kicked back, required a visit to emergency and crutches for several months. Forty years later I still have problems with that foot.

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