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Discussion Starter · #1 ·
Hey everyone..
im new to the forum but have been viewing it for a long while...amazing forum as the the advice has given me confidence to try anything. My issue today is i have an 87 thats been making more than usual wack at tack a tackin for a while since purchase and sure enough..intake valve tip is no longer a tip..and the tappet screw tip split on end.
First I tried .003 by feel since a guage cant meausure it properly and it helped for moment ..but tackety tack got louder and came right back by the end of the first ride... tappet screw is so deep almost last threads of nut..

So I have the replacement parts and spring compressor.. heads all apart but the spring wont compress away from the valve tip to pull the clips....like its caught on it the mushroomed end..that being said the retainer clips are no longer visible.. im about ready to try drilling the valve tip out and hopefully save the retainer clips.. any advice before i attempt such a drastic approach to try drilling the tip?
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I think you just need to be bold and crank harder on the compressor. It will eventually give. Maybe cover it with a towel in case it releases violently.
Can you use a battery powered driver to run the compressor? The rat-a-tat-tat of a driver may jog it to release.
 

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Cut a piece of wood so it is angled to support the large end of the valve on your workbench. Then use a deep wall socket over the small end of the valve and retainer clips. Then, using a rubber dead blow hammer, judiciously rap the end of the socket to see if you can free things up so the retainer clips become unstuck. Cautiously increase the force of the blows and/or the size of the hammer until it either frees up or you risk causing more serious damage. Then you might have to get out the Dremel tool and start cutting. Good luck!
 

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Thanks both..Ill try a little harder on the spring compressor although the C clamp was actually bending and i turned it until i could no more....that mallot and socket plan seems plausible..or if possible fandangle the combustion end of the C clamp so its not on valve so the large end of valve opens when compressed.. then tap it other way to free it up from the retainer... i imagine my drill bit plan would end up spinning the valve stem anyway.. .. ill keep yall updated..
 

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I like the Dremel idea TW-Brian mentioned (and the socket hammer :)). It looks like you just have to remove a bit of valve tip material so the retainer clips have room to "escape".
Good luck and keep us posted on what method or methods worked.
 

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TW-Brian has the solution. I used to use that technic when I didn't have a spring compressor. Deep socket and a hammer worked every time..... and of course Admiral would like the hammer method ;)
 

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Damn - that looks familiar! I had the same thing happen to my '87 back during the summer of 2019. Though, my retainers may even be broken. I found a very low mileage and inexpensive engine from a 1988 Black Widow as a solution. I never tackled the repair and the engine is still in the shed awaiting revival. I'm sympathetic to your plight. Please update the thread with the progress of your repairs - I am very interested!


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Discussion Starter · #8 ·
Ok everyone..got it out and new valve lapped in this morning.. i retried the cclamp spring compressor at different angles and it finally pulled away... because the clamp compressor is hard to stay true it binds the spring shield retainer one way or another catching the smashed tip and locks... the same thing required to get my locks back in (using the tiniest dab of grease to hold in place as no third arm
Now just to assemble everything and test it out.. switchin to family saturday now.. will update...
 

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Discussion Starter · #9 ·
Success!
Although it might be another thread..
while I had it apart i cleaned up the carb and upped my 115 to a 116 main i had lying around ..note this bike has a DG and my AM screw at 1.75.
She fired right up and yet wouldnt hold idle but ran fine and smooth with a little gas.... so I turned AM out to 2 turns and adjusted throttle screw until 1400 rpm... purrs at 1400 idle just fine..with no more excessive tickety tack.
However on a ride intermittently she feels like shes bogging down a bit usually at mid to high throttle... a little like engine break even though throttles on.
Could it now be a lean condition now even though i upped the jet perhaps now conpensating with throttle position?
Boot on intake to carb doesnt seem to line up perfect but its always been a little beat and kinda like that.
1. Im going to realign the boot as best possible.
2. Recheck the TDC timing.. i had both marks up perfect and spinning true yet before i reinstalled the manual tensioner... that shouldnt matter i dont think.
3. Turn the AM screw to 2.5 out as i see some do.
4. Perhaps try an even larger Jet..i think i have a 118 to 120 around....
Any other thoughts?
 

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Discussion Starter · #10 ·
1. Boots tighter - air filters clean n oiled
2. TDC lines up both marks
3. Turned the AM screw to 2.5 out..
Test drive.. way worse.. idle fine.. throttle starts dying out ..could barely get to third.... eventually stalled... fired right up again..took it home..
Before i try jetting .. going to recheck the valves once cool as read they can tighten up again if set on the bench.
 

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I am by no means an expert in this, but from reading the forums I know the 87‘s were prone to CDI issues. This can seem like a carburetor problem. I don’t think there is a good way to troubleshoot this other than replacing the CDI with a known good one. Was your bike was running OK before the valve problem?
 

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When the end of the valve gets to be concaved
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And the ends of the adjusting screws look a little rough
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you better start thinking about new parts. You can postpone it for a long while if you polish the ends of the adjusting bolt and the end of the valve stem. Or you can ignore it..............
I used a rubber wheel on a Dremel.
 

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I had end of adjuster bolt start spalling off small metal chunks from end where elime polished. Replacement was my solution.
 

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I am by no means an expert in this, but from reading the forums I know the 87‘s were prone to CDI issues. This can seem like a carburetor problem. I don’t think there is a good way to troubleshoot this other than replacing the CDI with a known good one. Was your bike was running OK before the valve problem?
Thanks Dave and all..i will check the CDI... i think i read you can freeze or squeeze it.. indeed it had started to fade a very seldom for a few weeks before mid throttle before i replaced the I.Valve.. why i looked at ot more closely....but i assumed it was due to the smashed valve .. after the valve change it started inmediately but seemed alot lower rpm..i figured things needed to lube up.
i ve tried all 4 things i listed plus the breather hoses and on valve check.. indeed my valves were tight after head mount as i had set the lash on them while on the bench..
But to no avail still starting and idling clean and stationary throttle..but bogging on throttle in gear..alot worse now.. couldnt get to the street now. i tried Amscrew back down to 2 but no change
Perhaps last few things is to
1.check compression in case my lapping was not to spec.. but i had checked the ' liquid solvent leak test' as per the manual..
2. try my 115 Jet which was running well for a while. (original owner had a 106 in there with a DG and KN .. it had a pink pipe in the dark).....im not sure if the needle on the 87 carb can or should be adjusted..since i went a little richer
3. Check CDI
***Note i do own a 2021 as well..anything i can swap to validate anything?. CdI?
 

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Thanks Dave and all..i will check the CDI... i think i read you can freeze or squeeze it.. indeed it had started to fade a very seldom for a few weeks before mid throttle before i replaced the I.Valve.. why i looked at ot more closely....but i assumed it was due to the smashed valve .. after the valve change it started inmediately but seemed alot lower rpm..i figured things needed to lube up.
i ve tried all 4 things i listed plus the breather hoses and on valve check.. indeed my valves were tight after head mount as i had set the lash on them while on the bench..
But to no avail still starting and idling clean and stationary throttle..but bogging on throttle in gear..alot worse now.. couldnt get to the street now. i tried Amscrew back down to 2 but no change
Perhaps last few things is to
1.check compression in case my lapping was not to spec.. but i had checked the ' liquid solvent leak test' as per the manual..
2. try my 115 Jet which was running well for a while. (original owner had a 106 in there with a DG and KN .. it had a pink pipe in the dark).....im not sure if the needle on the 87 carb can or should be adjusted..since i went a little richer
3. Check CDI
***Note i do own a 2021 as well..anything i can swap to validate anything?. CdI?
There are a lot of differences in the 87 and newer electrical systems. I don’t think I’d try swapping with the ‘21.
 

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Discussion Starter · #16 ·
So compressions at 160 ish.. way above the 149 max... i suppose at least i know my new valve is sealing nicely! I do recall some carbon i tried to clear from the head of the piston but def some left behind. i wouldnt think thats new enough to cause the bogging issues.
Btw reseated my front pipe and removed the smallest amount of packing build up in the FG screen. It warms up fine..stationary throttle revs fine.. then im able to drive away for a few minutes without issue..then bogs and/or jerking .sometimes a stall.
Ill get back into the carb and pull the 115 mains back in..ensure pilot and mains are tight and check float height and gas levels .
 

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I remember having an issue like this on my 87 and ended up swapping the carburetor for the newer model. I got tired of checking, cleaning and rebuilding it again and again. It solved the issue and it felt like I gained a bit more power from it.
 

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Discussion Starter · #19 ·
Success!! very happy to report shes runnin great and has even more pepp!
Very happy to find my own stupidity.. i didnt tighten down that 116 main jet enough... i opened up the carb and she fell out into the bowl..
The jet has a 7mm hex and the main jet holder has an 8mm.. so looks like i didnt seat the jet properly to the main jet assembly..
Phew!.. that loose main jet trouble shooting for bogging at mid to high throttle is even in the service manual..

And.. valve seems great.. i might try to clean that carbon off the top of the piston to lower that compression if i ever get around to it.. but all seems great now!

Thank all for enduring my plight!!
Happy dubbin
 

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Discussion Starter · #20 ·
One more funny story in this.. so i went for a longer ride.. good a far from home..shes rippin good up a gradual hill..
Get to the top and roll off to gear up... let go of the throttle..dies.. curbside get her started with choke only... keep some throttle keeps going but shudders and dies again.. limp all the way home.. rip out the carb.. unscrew and recheck everything again and change jet back from 116 to 115.. put it all back together.. decide to check if gas cap is ok.. open fuel line into a cup.....nothing 🤔😞... flip it to reserve it flows🤣🤣🤣..what a waste of time it was simply running out of gas .... i coulda just flipped to reserve instead of overhaul the whole carb again.... and if i woulda just tightened the 116 jet properly after the valve job... would have avoided all of this tuning ..🙃 oh well.. i got learn alot .. 😁
 
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