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I've got my new main jets, a 130 and 132.5, and float bowl gasket, what do I need to change in there? I know there is a good write up, but I can't acess it. The search function isn't working. I know I need to raise the needle valve, how much? I'm at sea level? Which main jet, and whats the correct idle screw adjustment. Anyone else have problems with this site? Slow and lost site?
 

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http://tw200forum.com/index.php?/topic/647-carb-tuning/



It's in the Technical Help forum, second pinned thread.



Nobody can predict exactly what your carb will need. Too many variables as far as condition of your bike, weather, quality and type of fuel, how you ride, etc. Assuming 2001 or newer, a good place to start is 288−14343−66 .JET, MAIN (#132), one flat washer under the needle, pilot jet 2.75 turns out. From their adjust to the way the bike responds while riding. The above linked thread lists characteristics of a poorly tuned carb
 

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http://tw200forum.com/index.php?/topic/647-carb-tuning/



It's in the Technical Help forum, second pinned thread.



Nobody can predict exactly what your carb will need. Too many variables as far as condition of your bike, weather, quality and type of fuel, how you ride, etc. Assuming 2001 or newer, a good place to start is 288−14343−66 .JET, MAIN (#132), one flat washer under the needle, pilot jet 2.75 turns out. From their adjust to the way the bike responds while riding. The above linked thread lists characteristics of a poorly tuned carb


While your in there I'd replace the air mixture screw assembly. Its only about $12 bucks. There is a very tiny rubber o-ring at the very end of it. sometimes gets lost, dried out, crushed, etc.

It only comes with the complete assembly.

screw/spring/washer/o-ring

and... I'd run 2oz of sea foam to a full tank of gas to clean everything else out.

then...I'd run 1/2 oz of Marvel Mystery Oil in every tank thereafter to keep things clean.

Good luck
 

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... There is a very tiny rubber o-ring at the very end of it. sometimes gets lost, dried out, crushed, etc.

It only comes with the complete assembly.
I recently purchased a bag (100) of those tiny o-rings from McMaster-Carr. I'd be happy to send one along (while supplies last) to anyone in dire need.



jb
 

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Perfect, guys thanks for the links, that's just what I needed, I'll print them for future refrence. Hey jbfla I'll take one of those o-rings, if you have any left. PM me
 

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Guys need a little help. I did the 130 Main jet. raised the needle by .05. The only thing I did not do was to drill the hole to 7/16 first of all I didnt have the drill bit and I have being sick. I couldnt get to town to purchase one. Is this going to affect the bikes performance. I putt it all back together in the garage and it started without using the choke and it sound it even more sponky than usual. But again I was not able to take it for a ride, too cold and I dont feel good.

Erod
 

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... The only thing I did not do was to drill the hole to 7/16 ...Erod
Erod, my memory is failing me rignt now. Where did you get the 7/16 number? That sounds quite large for the hole into the vacuum chamber.



The number that sticks into my mind is 1/8". If you make the hole too large there won't be enough vacuum to raise the slide (and drilling the hole is irreversible).



jb
 

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Wow, I am glad I didnt make it then. It is on the centerline web that you post it above(post #2). Look at the pictures and it shows the drill area and 7/16 drill bit. Do I need to drill the hole? and if I do could you tell me what is the correct drill bit.

Thanks,

Erod
 

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Drilling the hole on the slide affects the response of the throttle when you twist it open fast. It is not a necessary part of what you have already done.



Since drilling too large can hurt performance, try riding a while without.



Then if you are not happy, carefully drill the hole a little at a time until you get the throttle response you want. Remembering, it's a lot harder to put metal back in the hole.
 

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Wow, I am glad I didnt make it then. It is on the centerline web that you post it above(post #2). Look at the pictures and it shows the drill area and 7/16 drill bit. Do I need to drill the hole? and if I do could you tell me what is the correct drill bit.

Thanks,Erod
Erod,



My mistake. I thought you were referring to drilling the hole in the slide in the vacuum chamber.



The 7/16" drill bit in Centerline's rejetting thread is for drilling out the plug which covers the pilot screw. This plug should be removed so you can adjust the fuel/air mixture for idling.



You can use any size drill bit to enlarge the hole in the plug, then carefully pry out the rest of the plug.



Just don't drill too deep. The plug is only 2 mm thick. When you remove the plug you will see the brass pilot screw underneath.







jb
 

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Well the sun came out and the temp went up to 65 Degrees. I took the TW for a spin. I noticed more pick up at starting and mid range. Top end I did not try yet. Thanks guys for all of the help. The next mod is going to be the stage one cam and that will be it for performance.



Thanks again for all of the help,

Erod
 

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Thanks Centerline and others, for your advice, explanations and pictures! For my 2001 TW200 with ethanol problems, I decided to let the dealer do the carb cleaning (everything inside the carb was bright yellow from the ethanol residue). When I got the cleaned out carb back, I added socket head cap screws to the float bowl for easier access. I drilled out the plate/plug over the idle mixture screw, and changed the setting from the stock 1 turn out, to 2-1/2 turns out. I added 3 x .01 shim washers to the needle. And I removed the stock #126 main jet and replaced it with a #128 main jet. I viewed these steps as a conservative way to increase performance, without trying to approach the bleeding edge of carb tuning.



Wow, am I ever pleased! At startup I need little or no "enricher"/choke to start the engine (note that it still needs to be warmed up before moving off). It is more "ready to go" at any speed, and there's no indication of any troublesome side effects. The engine simply seems to run more smoothly, and to take throttle more readily, at any engine speed.



My only regret is that I didn't do this mod years ago, since it would have made off-road riding a whole lot more fun.

- - - Happy trails, Jim
 

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guys, im a carb newbie here and ive got plans on tweaking my current carb a lil bit.

im riding a 2010 model and i mainly commute on normal roads but i have a pillion with me most of the time.



i just want that extra power and less of the sluggishness.



what do you carb pros suggest? is there anything else i need to change besides the carb?





thanks!
 

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Yes. You'll need a different motorcycle. Another TW for her will do nicely to improve performance.




At normal altitudes, say sea level to 4000 feet, a #130 main, 2 flat washers pounded a bit thin, and 2.5 turns on the pilot is sweet, unless the air temp is really hot, in which case a #132, one flat washer under the needle, and 2.5 turns on the pilot screw will be a bit rich and will serve to lower engine temps a bit. If you want best fuel efficiency go with a #128, 2 flat washers under the needle, and 2.25 turns on the pilot screw.



Higher than 4000 feet or so go with a #128, 1 flat washers under the needle, and 2 turns on the pilot screw.



Above 7000 feet, #126 main, 1 washer, 1.75 turns on the pilot screw.



That all works on Tdub, most of the time. YMMV.
 
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