Smoking Tlr200 + 24mm Carb Swop?

[stump magnet]

if the float height is totaly wrong on the standard carb to the point that it pours from the overflow whilst running would this cause excesive smoking on start up and very slight smoke when running, the float is twisted all over the place and needs straightening, im hoping that its not rings although ive pulled the engine from the frame to check the valves stem seals and replace a ratley cam chain it has good compresion though and pulls fine im just having trouble sorting the float height. on a seperate note i have been given a 24mm more modern mikuni carb from a xr/xl185/200 which fits straight on is there any performance advantage using this bigger carb or will it lose bottom end.

[copemech]

Bluish grey smoke is oil, and black smoke is fuel! Which is it?

You can have good compression(oil makes for good compression), yet still a broken, stuck or worn oil control ring!

Did'nt mean to spoil your day mate!

Cheers,

[stump magnet]

ok have stripped top end, piston and bore are good as is the rings with no blow by marks valve stem seals very hard compared to new ones so have replaced them the valve seats appear to be fine also so putting it down to over fueling and valve stem seals the plug is very sooty and the head/piston and valves were also carboned up so gona clean up and rebuild as is and see how it goes but will check ring gaps before reassembly any thoughts on 24mm carb is it worth trying?

[copemech]

ok have stripped top end, piston and bore are good as is the rings with no blow by marks valve stem seals very hard compared to new ones so have replaced them the valve seats appear to be fine also so putting it down to over fueling and valve stem seals the plug is very sooty and the head/piston and valves were also carboned up so gona clean up and rebuild as is and see how it goes but will check ring gaps before reassembly any thoughts on 24mm carb is it worth trying?

All I can tell you is that typally the 4T motors like a smaller carb to keep the air velocity up which tends to minimize the lag time if you wick it! But you may have to see what happens! And if you find it acceptable?

[biffsgasgas]

if the float height is totaly wrong on the standard carb to the point that it pours from the overflow whilst running would this cause excesive smoking on start up and very slight smoke when running

So as I understand it the standard carb is over flowing right now?

Sounds as if your needle is not seating fully if this is the case.

Remove the bowl and push the float up by hand while it is installed on the engine and turn on the petcock. See if you can shut it off yourself.

The other carb could definetly cause lower rpm issues. If the jets and needle swap over from the standard carb i would do that as a starting point. A bigger carb may mean less venturi (sucking of the fuel from the bowl) and this would be the disavantage to lower end. At higher rpms size starts to not matter with venturi. Size of the carb can be a limiting factor to how the engine breathes at higher rpms. Other limiting factors are port size, valve size, exhaust size, and air filter size. In other words there are a lot of factors involved here. Experiment but try not to change too many factors at once. Start with Carb with old jets then put one jet in at a time to see what works for you.

[mcman56]

Is the 24 mm carb the same casting but with the oval bore taller than the 22 mm? (same width) If so, it will give you a nice boost at the top end with no affect on any other part of the power curve. Another local rider and myself use this setup. Just make sure the slide comes all of the way up on full throttle. The 22 mm slide will not open all of the way in the 24 mm carb........unless you shorten the top of the slide. (at least on the ones I have seen) All other components are the same. You can even machine a 22 to the 24 size.