[nickB]

So I have an 87 Tw200 and I have ridden it for 2 years now. The thing is starting to rack up the mileage(appx. 14,000). How many miles should it go before a rebuild? Are they re build able? And I have always had carb troubles with this bike. I have taken it to yamaha and they couldnt even get it right. I have re jetted, finely tuned, everything and it is still a jerk. Is it better to just get a new carb? What kind? Thanks!!

 

[nickB]

BUMP!!

 

[FortPayne]

Ya gotta be waaaaay more specific about what the problem is.



Wait...



Using my ultra super psychic future telling powers I'm gonna call it now- CDI.



Nah, really what's it doing?

 

[nickB]

It just runs rough. Every time i come to a stop I have to pull the choke out about half way or else it will die. I checked the cdi and had the dealer check it too and it is fine surprisingly. It has always had its issues. I think the carb is just extremely outdated and rough even though i have re built it twice. I think this machine need a new heart

 

[rm_hm]

If you rebuilt it with a keyster kit I know what the problem is

I've never seen one their kits match up with oem. There is always at least one part or more that's iffy at best in every kit. You need to compare all the parts with your original ones real good before you install them



I hope you don't need to resort to a new one.



I've heard in the past that yamaha dealers will charge you about $70.00 for a good carb cleaning.



A new non-cali carb for an 87 will set you back $315.00

If you have the skills to mod your bike to work with the current tw carb. It's only $243.00 for a Non California carb

 

[rm_hm]

Crud... Double post

 

[nickB]

It was all OEM parts for the carb. It was more expensive but I wanted to make sure it was right. And I had no idea there was so much trouble with the 1987 model. I found it on craigslist for $900 and it ran. It just had its issues as any old bike. But I have ridden it for a couple years now. I just think its time for a renovation. Id probably keep the stock engine and just rebuild it fresh. But I was more curious about putting a more modern carb on it. It has a kick start on it too, so im not too worried about replacing the electric started even though it still works fairly decent. I just want a reliable 1987 tw200 and think its about time for a project. It has 14000 miles on it currently.....I have had sooooo much fun on this bike. I used it as my sole transportation to and from school and work. Rain or shine, it was always there for me.

 

[FortPayne]

If your valves are adjusted and carb clean 14k isn't rebuild time for your engine. It isn't rebuilt time until you have smoke or compression problems. New carb is up to you but if it has stock jets and gaskets and your float is adjusted properly it ain't the carb. Plenty, and I mean plenty, of guys on the forum run 87's. The age doesn't cause it to run rough, neither does the mileage if it's all properly adjusted.



I guess I'm just saying it sure would suck to buy a new carb just to have it run the exact same. I don't know where your at but if your close to another '87 member the BEST way to know for sure is swap carb with another member and see if that clears it up. If not try the cdi- no kidding.

 

[rm_hm]

Try checking the plastic tube between the carb and airbox. They can shrink over time and if air starts leaking around it you will get some odd effects.

 

[DanUrie]

Try the old check for a vacumn leak trick.



Start bike up and get a can of WD-40 with a straw and spray a little around carb connection to manifold and engine block . If idle increases or engine dies you have an air leak. Then try around carb top and sides, could be a crack, bad throttle shaft seal or leaky threads around adjustment screws. Don't try on a hot engine or indoors. Watch out and keep a fire ext. around just in case.

 

[lizrdbrth]

Do everything the guys have suggested to rule out carburetion, manifold leaks, or other causes but don't fall into the endless "87 trap" of chasing a fuel problem, multiple carb rebuilds, a new carb, etc. before at least taking another look at the CDI.



Bear in mind that it's an '87. They're prone to CDI failures and they fail in a number of different ways. Sometimes they misfire, sometimes they trigger no signal at all, sometimes they have no spark advance and feel like the bike has a "governor", etc. Sometimes just squeezing their casings or turning them upside down will either correct the problem or make it worse.



Regardless of whatever your dealer told you there is no way to "check" a deteriorating CDI on a bench or sitting in the shop. The only way I've ever found to test an intermittent CDI is with a timing light capable of being operated on a moving bike. Take Ft. Payne's suggestion and try to locate a known good CDI to try before you go buying a new carb. If you can't locate one I'll tell you how to rig a timing light for bike use.