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Discussion Starter #1
I need some advice thoughts on a carb issue.

Bike is a 1994 California emmissions bike that is new to me. It didn't run perfectly when I got it for my wife so I put a carb kit in it. I also blocked off the line that goes to the Cali canister.

Long story short:

Bike starts right up but runs like its running out of gas for the first 15 minutes. Very off and on when on the throttle steady. After the first 15 minutes it finally cleans up and runs perfectly. There is absolutely no smoke. Runs essentially the same way whether choke is open or not. With it taking this long to run right it has basically made it unrideable as a daily use bike. We trail ride with it no problem but she literally has to deal with it coughing and sputtering for at least a full 15 minutes even on the warmest of days.

Not sure exactly what the heck other than I'm 95% sure it is carb related.

Own 15 bikes so i know my way around them but never seen one quite like this. It has to be close because it runs so well after its fully warm.

I realize new carbs aren't too expensive but I hate to go that route since this one is so close. I hate to start over troubleshooting a new carb.

Thank you in advance to the experts
Rob
Maple Valley WA
 

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Did you replace the pilot jet? They can be hard to clean good enough and it's usually best to just get a new OEM part. It might just also need to have the pilot air/fuel screw turned out. Gently seat it counting how many turns in it takes to seat, then turn it out to 2 and 1/2 turns and try the bike. Keep us posted. We'll get you through this. Lots of helpful folks here.

Welcome to the forum!! :D
 

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Discussion Starter #3
I did replace the pilot. Couple more things I should mention. I bought the carb kit off Ebay. Have seen threads discussing that isn't a great idea. I can see why it isn't a great idea as the internal carb parts weren't EXACTLY identical. They were obviously close and fit but weren't identical to what was in there. Not expecting to have issues I didn't keep the original parts (dumb) so I can't say for sure exactly what was different but I remember finding it odd.

I have not played with the mix screw. That does sound like a good place to start. Haven't wanted to effect the fact that it runs great when warm but I guess if I count my current turns I have nothing to lose.

Also bike has less than 2500 miles and is one of the cleanest of this gen I have seen. I would like a newer one with a front disc but my wife insisted on the cool orange one :)

Thank you for your quick reply. BTW...your verse was a Jeopardy answer this week....begotten Son! :)
 

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It used to be that when anyone got an aftermarket kit it was nothing but trouble and frustration. The last couple years though a few members have found a couple decent kits. Hopefully they will chime in because I can't think of the name of the manufacturer right now. TW's come very lean, especially the Cali models. When you adjust it out to 2 and 1/2 or so, they start up easier and warm up much easier. It will even give you a little more pep! Try it, you'll like it. I'm sure a couple members know what the jet sizes that were in there in case you end up starting over. I think it's the pilot right now though.
I did replace the pilot. Couple more things I should mention. I bought the carb kit off Ebay. Have seen threads discussing that isn't a great idea. I can see why it isn't a great idea as the internal carb parts weren't EXACTLY identical. They were obviously close and fit but weren't identical to what was in there. Not expecting to have issues I didn't keep the original parts (dumb) so I can't say for sure exactly what was different but I remember finding it odd.

I have not played with the mix screw. That does sound like a good place to start. Haven't wanted to effect the fact that it runs great when warm but I guess if I count my current turns I have nothing to lose.

Also bike has less than 2500 miles and is one of the cleanest of this gen I have seen. I would like a newer one with a front disc but my wife insisted on the cool orange one :)

Thank you for your quick reply. BTW...your verse was a Jeopardy answer this week....begotten Son! :)
 

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Welcome, fellow Washingtonian Rob,

Most likely the internal passages in the carb body itself are still gummed up. What "kit" did you get? What parts were in it, and what did you actually replace?

I usually recommend getting OEM carb parts, as you usually don't save that much $ and you know what you are getting is what you are supposed to get. Often, aftermarket kits are reviewed as of poorer quality and may include unknown or incorrect parts and jets. I always recommend replacing the jets and most replaceable internal parts. That's me.

On the older carbs, I really recommend tearing it all the way down and using a ultrasonic cleaner if possible. It is really important that all of the passageways get fully clear. If you want to try going cheap and easy, you can try adding a half to full can of Seafoam to a fresh tank of fuel. FYI, Seafoam says you can run up to a 50/50 mix. Run it, let it sit, run it, let it sit, repeat. It might just clean it out for you.

In the meantime check out our "Technical Write-ups" sub-forum for all of the tech stuff like this gem...http://tw200forum.com/forum/technical-write-ups/10798-how-bring-sitting-bike-back-life.html

Good luck man, and keep us in the loop.
 

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Also, make sure to check on the condition of your boot from your carb to the motor. Many of these have shrank or cracked allowing extra air in, making proper tuning impossible. It is recommended to change this every ten years or so.
 

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Mixture needs to be 2+ turns and no vacuum leaks.
Check the mixture screw setting and use an unlit propane torch to check for vacuum leak (listen for change in idle speed)
 

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Discussion Starter #8
As far as what kit got put in it. Im not sure....generic off Ebay. This is all the info left from the auction
Ashampoo_Snap_2017.06.07_21h22m57s_001_.png


As for what parts got replaced....that's alot of the problem. I put the kit in this winter when I bought the bike. I replaced the parts...put it back on and it started right up and idled. Not thinking there would be a problem come riding season I threw all the old parts out and can't remember exactly what got used and what didn't get used. I did soak the carb in Berrymans cleaner when I did it and blew it out. It still idles well and seems like its going to run perfect...then as soon as you take off to ride it kicks and seems to starve for fuel. I can verify the boot is very new looking and the plug is new.

Its dark here tonight so work will start tomorrow night. I will start with a fuel screw adjustment. If that doesn't do it I will pull the carb and get some pics of the current parts. I would be fine with buying a new carb kit to know my parts are the exact parts it should have. Just need the recommendation of which kit that would be.

BTW...Johnny...i actually bought this little guy in Hayden, ID so its from your neighborhood. :) Other than VERY notchy head bearings its been great. My wife loves it (now that I finally put new head bearings in it) but she would ride it a whole lot more if it ran better at startup. She keeps thinking its going to leave her stranded b/c its not perfect.

Thank you for your help guys. I will keep the thread updated as nothing drives me crazier than finding a thread with my exact issue only to find the original poster didn't loop back to explain what ended up fixing it.

Thanks again,
Rob
 

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I usually get my OEM parts from http://www.rockymountainatvmc.com Click the OEM section, then drill down for your parts off of the diagrams. I like them because their site tells you if it's in stock or not. If so, then it's at my door here in the PNW in 2 days. They also have flat ship rates. If you go OEM, you won't get a "kit". Pick and pull the parts you want/need.
 

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Always good to get a bike people like, easier to get them out on it with you.

The Shindy carb kits I've used have been ok. But I think the Yamaha stuff is nicer.

Hardened carb boots could be the issue. It's needing more gas when cold than normal. But then runs good so small air leaks makes sense. Or low speed fuel blockage.
 

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Discussion Starter #15
Here is my update from the work I did last night. End result....its running worse. :-(

Started by pulling the carb to take a look at the fuel screw adjustment. I had hoped it would be in too far and simply backing it out would help. Nope. The screw was out 3 turns. Realizing this adjustment was likely not the problem I went for another clean. Pulled fuel screw...jets....float...soaked all metal parts in Berrymans carb cleaner then with carb cleaner and an air gun blow off.

20170608_194228.jpg

Then the fun began. Took everything I had to get the carb seated in the rear boot. The rear boot is in good nick but seems very hard. Ended up pulling the intake boot and got the carb in and clamped. It almost seems like the span the carb needs to make is too long. Like the boots are too short but I believe that is just b/c the odd way the rear boot will rotate.

Started bike. Runs but very unsteady idle even with choke on. Half choke it runs a little better. Will not stay running at no choke idle for more than a few seconds. It runs very similar to the way it did before except for now it doesnt seem it going to clean itself up and run right. This was with fuel screw out 2 1/2. Tried unlit propane torch all around carb...no change.

I then pulled the tank again and pulled the plug. Its definately a lean condition. Tip of the curvy piece on plug (technical term) is very white. Replaced plug just for funsies. Runs the same. Tried to adjust fuel mixture screw without taking carb off. Could not get a good idea of if it was helping or not until I backed it off too far and lost the mixture screw spring in the dark driveway. BTW...that thing sucks to adjust with the carb on and a hot exhaust.

This weekend it will be find the spring. Reinstall to 2 1/2 turns and bang my head against the wall more. Starting to see a new carb in my future.

Hoping the pic of the blown up carb might help the experts know if the parts seem wrong.
 

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When there is not a lot of difference in the way the choke works, it usually points to the pilot jet needing cleaning or replacing. You replaced it and the adjustment is probably close. It does sound like the boots have shrunk. I would replace them. How's the intake manifold?

I'm wondering if you have any forum members near you? You could swap carbs for a minute and see?
 

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Discussion Starter #17
When there is not a lot of difference in the way the choke works, it usually points to the pilot jet needing cleaning or replacing. You replaced it and the adjustment is probably close. It does sound like the boots have shrunk. I would replace them. How's the intake manifold?
The intake manifold looks darn near perfect and is very soft. The air filter side is the hard side but seems very difficult to get out of the box. Maybe thats because it has hardened so much. I looked at the larger jet and could see a 40 on it. maybe its 140?
 

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Did you try SeaFoam or Lucas Deep System Fuel Cleaner yet? I personally like the Lucas, it's saved me a few times from even having to open a carb. Put several ounces in it and run the bike. Was there a rubber o ring on the pilot screw? If none of this works, you may end up having to buy OEM parts and starting all over...after you replace the boots.
 

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When there is not a lot of difference in the way the choke works, it usually points to the pilot jet needing cleaning or replacing. You replaced it and the adjustment is probably close. It does sound like the boots have shrunk. I would replace them. How's the intake manifold?
Four common reasons for lean (and your symptoms are lean) as exhibited by choke effect:
1. Mixture screw too far in (you checked that)
2. Air passages obstructed (you have cleaned)
3. Pilot jet obstructed (you have examined, but could also clean with safety pin, if not already replaced)
4. Intake boot/seal allowing vacuum leak. On H-D V twins, a VERY common problem, especially on old intakes and the carb inserted dry. Always moisten when reinserting (spit, water, diluted soap). I did not re-read, maybe you have already checked, but an unlit propane torch will indicate a leak by a change in idle speed when propane applied.

BTW: The air filter boot leaking would allow dirt to enter the carb, but not affect the mixture.
 
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