Nope.

 

Gee you were almost not wrong. At least you were brief...must be a new KF record.

I've ridden this bike with the 36's AP disconnected. Have you?

- You're overlooking the mechanical slide control's substantial contribution to throttle response. Especially when the AP invariably makes the a/f go richer by as much as a couple points.


Pull your choke out just a little next time you need a shot of power and see if that works out well for you.

 

OK...I'll add a few words. Most of the throttle response benefit in the pumper carb is because of the squirt.

 

Being old 2-Smoke rider for most of my life - I hate the abrupt surge of power the AP gives 4 strokes..

 

FWIW, more goofing around the net...

The VM38 on the KLR thread at the ADVrider forum got me looking more.

Seems XRs Only uses the TM34-2 for their 90s XR250 slide carb kits including recommendation for the big bore 250s, the TM36-2 for the older 350s. They use the pumper for the 400s and 650s. So it makes for the TM36-2 more interesting, although a TM34-2 might work better due to similarities in the engines and at $140 new, ain't too shabby.

There was a comment from another inmate about the slide carb being 70 year old technology and that DRz400 riders were converting to CVKs. But with a quick search I found the "converting" was not actual conversion. They were putting 40mm CVKs from KLX and KLR650s on the 400s. I'm sure they can get those carbs on the cheap too.

 

Playing with motors is fun, but I don't know if your going to change the rotation of the earth with your discoveries.
My 2 cents.
I my world, at WOT, there is virtually no difference in a CVK & slide carb with the same ID. It is just a tube with gas getting sucked in.
At part throttle it is a different world. The CVK relies on air velocity thru the carb to lift the slide, limiting the amount of air & fuel allowed into the cylinder. The slide carb allows the maximum amount of air & fuel into the cylinder as it is releasing full air pressure minus the friction loses to charge the cylinder.
If the engine can take the full charge of the slide carb without stumbling, it will operate with more response at any rpm.

 

I'm fairly realistic. I don't really intend nor expect to alter the earth's rotation, just looking at performance options at reasonable cost. As you say, it's fun to play.

Of course you are right about carb throat size although there is the portion of the area taken by the butterfly/shaft. Not much, but some of the cross sectional area is taken. Then there still is a reason that knowledgeable tuners may replace constant velocity carburetors with slide carburetors of the same size or possibly even smaller. So simplifying the function to the point of being "just a tube with gas getting sucked in" might be a bit of an understatement. XLs Only use the TM36-68 on XR/TRX400, the same size as the OEM CV, and they use the TM40-68 or TM42-68 replacing the OEM 42.5 CV on the XR650Ls. They must know something is working better there.

The performance gain, if nothing else, is in faster throttle response by eliminating the delay in the slide action and no butterfly blocking the way. The point to the XRs Only comment is the fact that even with the availability of the TM36-68 series they have stayed with the TM34-2 series. Makes me believe the 2 series would work on the KLX with reasonable results. Maybe not as good as the 68, but possibly significantly better than the CVK.

It won't alter the earth on its axis, but at around one third the price using the TM34-2 or the TM36-2 might be a decent deal for a KLX250 rider. Kind of like using a slip on exhaust instead of a full system to help boost performance, not the best or most, but better than before.