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Discussion Starter #1
I have a couple of 2015s. They both seem to run identically. They are very cold blooded. They pop a lot on deceleration. Once warm, they seem to snatch and surge when cruising at small throttle openings. Revving up off idle while in neutral seems sluggish. At moderate to high throttle openings and loads the bikes run pretty good. Doesn't surprise me, the last few carbureted bikes I bought new behaved the same.

Anyhow here are my questions:

Where is the idle air screw on this carb?

If it is under a cap, what is the best way to access the screw without screwing anything up?

Do we know what pilot jet came in these? If not, would the dealer be able to look this up and order a bigger one?

Do we have any members who have been down this exact path already that could provide any helpful wisdom?

Thanks
 

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?..

Do we have any members who have been down this exact path already that could provide any helpful wisdom?

Thanks
Nearly everyone.

You can start by reading some of the Tech Write Ups

http://tw200forum.com/forum/technical-write-ups/

2 1/2 turns out is the usual starting setting for the pilot screw, but you will need to fine tune it from there.

Jetting depends on your elevation.



jb
 

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Discussion Starter #5
I have read the write ups, thanks. I live and ride at about sea level, with most average temps around 65F, freezing to about 95 are the extremes and I don't intend to rejet for weather changes.

With a stock engine is an air screw adjustment normally enough to get things straightened out or is a bigger pilot jet and/or needle shim needed too?

I ask as I see no sense monkeying with air screw alone first if it is know for sure that the carb is going to need to come out for a pilot jet change as well and then the air screw readjusted after.
 

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I think the reason most rejet is a FMF or DG muffler yours is still stock?
 

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All you need to do is remove the plug and adjust the idle mixture screw (2 to 2 1/2) and keep your air filter clean. I cut down and grinded a screw driver to adjust.
 

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And 2015 you are doing the break in.
 

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I put the Procycle kit in a few weeks before we did the 2014 Moab trip and I could not dial it in so I put it back the stock and did fine.
 

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With a stock engine is an air screw adjustment normally enough to get things straightened out or is a bigger pilot jet and/or needle shim needed too?

I ask as I see no sense monkeying with air screw alone first if it is know for sure that the carb is going to need to come out for a pilot jet change as well and then the air screw readjusted after.
Try adjusting the pilot screw first, and see how it runs.

If it still surges, go up one main jet size, 128 Teikei jet.

You don't have to completely remove the carb to change the jets.

Loosen the carb clamps, rotate the carb 90 degrees, and remove the float bowl.

Replace the bowl screws with socket head bolts.

Needing to replace the pilot jet is rare, and is usually only to compensate for another problem.

Save shimming the needle until last. It may not be necessary, but will help with your perceived sluggishness.

Make only one change at a time, then see how the bike runs before trying anything else.

jb
 

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Discussion Starter #12 (Edited)
Well I took the plug out. The stock setting on the screw was out 7/8 of a turn - sound about typical?

I didn't have time to play with it much tonight but I found that at about 1 1/2 turn the idle seemed to peak. At about 1 3/4 turns just about all popping on decel is gone, though at a light cruise at 40 or 45 MPH in top gear with minimal throttle opening there is still some surging. I will work with it more this week.

Feels really flat as throttle is opened farther. Don't know if it is jetting related or just that the engine is really restricted in stock form.
 

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I believe that the stock screw setting is 0.95 turns in the manual.
 

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For your comparison, I got my 2015 a few weeks ago. I have the decel pop as well, but on mine it goes away after it's warmed up. I do not have the rest of the symptoms you have. I checked the plug, and it does appear to be on the leaner side of normal, but ok. Since I have less than 500 miles on it, I'm going to leave mine be for a while and will probably adjust the pilot screw as jbfl mentioned at a later date.

When my 2005 was new, I did not have the decel pop as we have on the 2015. This past spring after repairing a faulty float valve spring o-ring, my 2005 started running lean. Pop on decel just as the 2015. I ended up turning the pilot screw out to 2 1/2 and it ran great, so I'm pretty sure that's where I'll start when I do adjust my 2015.

What I've noticed so far with my 2015 compared to my old 2005, I can't measure it, but it feels quicker off throttle at all speeds. Overall power and top speed is the same however.

Good luck, I'm sure you'll get it fine tuned.
 

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For your comparison, I got my 2015 a few weeks ago. I have the decel pop as well, but on mine it goes away after it's warmed up. I do not have the rest of the symptoms you have. I checked the plug, and it does appear to be on the leaner side of normal, but ok. Since I have less than 500 miles on it, I'm going to leave mine be for a while and will probably adjust the pilot screw as jbfl mentioned at a later date.

When my 2005 was new, I did not have the decel pop as we have on the 2015. This past spring after repairing a faulty float valve spring o-ring, my 2005 started running lean. Pop on decel just as the 2015. I ended up turning the pilot screw out to 2 1/2 and it ran great, so I'm pretty sure that's where I'll start when I do adjust my 2015.

What I've noticed so far with my 2015 compared to my old 2005, I can't measure it, but it feels quicker off throttle at all speeds. Overall power and top speed is the same however.

Good luck, I'm sure you'll get it fine tuned.
Mine is a 2015 and no decel popping. It revs a little high in low gear which I expect to be somewhat normal. After a few hundred KM I noticed it opening up and more apt to wheelie in 1st. I think I got lucky with my carb settings for coastal canada since I heard they set them to meet california EPA regulations. Maybe my local dealer set it up right. I still want to try opening up the jetting but it runs acceptably.
 

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the motor will only rev as high in 1st gear as you let it. my 2014, like yours ran acceptably, all though I never felt it wanting to pull the front wheel. after buying a jet kit from procycle, mine now runs great, but still don't feel the wheelly thing going to happen. the jet kit was the best money I have spent on the little dubber, but then I haven't bought a seat yet
 
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