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Ok we all know the Legend of "Worlds Fastest 87 TW200" but I recently pulled from storage a nice 2000 TW with 487 original miles a CA Model not that it matters and I cleaned the carb which seemed easier to work on than the later model carbs and installed a fresh battery and when I test rode it the TW seemed noticeably more powerful than my later model TW ie 2001 and later
I got back on one of my 03's with 78 actual miles which I had refreshed the carb and battery a day earlier and it was just not as "snappy" as the 2000
My question is do the early models have a different camshaft or is the early model carb more efficient or am I simply imagining things lol ?

I rarely mess with the early models and only take them when I have to buy a package deal. I have another 1999 TW from New Jersey with 98 actual miles I'm going to prepare for sale this week I'll report back as to whether it has the pep the 2000 model had
 

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The engines are identical, the difference is in the carbs. CV carbs slightly dampen the throttle response since the slide is vacuum operated with the intent on keeping airspeed through the venturi constant (hence the Constant Velocity), which gives better "driveability" and helps emissions as well. With a plain slide carb if you snap it WOT from idle there's always a bog. The venturi rapidly changes sizes and airspeed slows, which kills the venturi effect that sucks fuel out of the bowl. Air is a fluid and has inertia just like anything else. CV carbs only widen the venturi as airspeed increases from increased engine draw.

So they run smoother and generally nicer, the trade off is in certain ranges they do not have the snappy response of a slide.
 

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The 94 TW Bee I have ridden is "snappier" as you say. The 94's carb was tuned considerably by Mr. Bracket. My 2015 TW is the same or maybe a little bit faster on the haul but as you are alluding too, not as quick on the draw.

I have the same slide type carb on the 83 XT200 and it also has the same snappiness of the 94 TW but not the long legs of the 2015 TW.

Purple's response is why.
 

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CV - "Gentleman's carb".
Slide - "Giddy-Up carb".

Give me that snappy response anytime, I'd rather deal with with the bog.
Kinda depends on the type of riding you do and how you like to do it.

Has anyone done a retro-fit of a slide carb to a late model?
 

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Just like the President there was no collusion. Yamaha didn't conspire to make the new model TWs slower, just a function of the carb change. Now maybe if you had friends in high places obama smollet.jpeg , or your Aunt was running for president kamala.jpeg you could change things and get special treatment with a pumper carb.
 

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Pumper carbs are a common mod in DR-Z land, especially if you do a big bore or other engine work. The stock carb is mushy and quickly becomes a restriction once you open other things up. I drove a friends DRZ with the stock carb (exhaust, jetted,ect), and it ran well but still had that trademark Japanese dual sport "softness". He did a pumper slide carb swap eventually and now it felt like a 4 stroke motocross bike or a KTM enduro. Snappy as hell. It was still a pig in the trails, but in Sumo trim it was pretty fun.

Snipping a couple coils off the CV slide spring and enlarging the hole in the slide can help restore some of the mushy tendencies by making the slide a bit more "lively" and responsive.

I'd be curious about a pumper carb on a TW, but to be honest I can't really complain in the slightest about how mine runs. I've learned my lesson about fixing things that aren't broken, or more accurately, screwing around with working things until they are broken.
 
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