I've been riding the new 240 with a carb that was dumping fuel in at an astonishing rate. It seemed to run OK but went through a tankful in about an hour and a half or so, with a black plume appearing on the white rear fender. I had disassembled and cleaned the carb when I got the bike and noticed a deformed tip on the needle valve and a pinched o-ring on the pilot jet, so thought I might just be able to improve this fairly low-mile carb with a new needle and seal kit. I ordered the parts from Mr.Wright, got them here in Canada in 6 days, and installed the kit. Starting is much improved now, and after a day's ride there's still gas in the tank and there's a tan coloured plume on the white fender (mudguard). Improvement to be sure.

The problem is that it still seems to run the same, not bad, but fat like it's still too rich. The "air" screw, as it's called in the manual, which I think is a "fuel" screw is said to be originally set at 2-1/2 turns out, but mine came to me with it set at 3/4 turn out and still runs best there. Jetting in the carb is as standard, nothing changed, yet. The other problem was that the idle speed screw wouldn't screw in far enough to affect the idle. The spring would bind before it screwed in far enough to raise the idle enough to keep it running. I found a similar spring and cut it shorter to fix that problem.

So, should I just spring for the preset OKO, or can the Dellorto work, and I'm just missing something?

The 240s came as std with a 98 or 100 main jet. Assuming you are not running hundreds of miles on the road , ot riding like a crosser, put a 95 in it. it will be much better

Lee

Edited July 6, 200917 yr by Lee Harris

I had Similar issues with mine when I first got her ... But to transform your bike into a responsive , crisp , one kick wonder ..., Get a OKO from Classictrial , A K&N airfilter , A denso iridium plug , and if it hasn't been changed out yet , update to a modern coil from Steve Goode .

The money spent on these few simple little things will transform your bike from a 80's semi reliable good twinshock into a modern bike with 2 shocks !

Remember the Dellorto is 25 years old , and no matter what has wear on the slide and bore that will make tuning a challenge , Don't waste your time and energy kicking a dead horse ! and if you get a new carb , make sure you have a new intake rubber too, Just makes life easier !

Glenn

Thanks Lee and Glenn, I think the first thing I'll do is see if it runs better without an air filter, and pick up a K&N. The foam in it is pretty old. That might just crispen up off idle. After that, I'll disassemble the carb one more time to check the pilot jet. The stamped number is too small to easily see. I'll use a microscope if necessary, and check to see it hasn't been redrilled.

Lee, the main jet doesn't really affect the off idle crispness, my only real complaint, and the standard 98 that's in there wouldn't really be that far off considering I'm at sea level, so I don't think that's it.

Glenn, If the pilot is still standard as I suspect, I could go down a size on that. I'm going to do a better inspection of the slide bore and if I see any wear at all, I'm just going to bin it and go for the OKO. That said, wouldn't wear in the slide bore make it go lean? I seem to have a rich condition at idle...

It IS a fuel screw isn't it?

VC. , A pn# E-3211 K&N fits the airbox great with a strip of self adhesive weather strip added to the edges to make up for the irregular surface of the airbox . I ran a 96 main in my delorto and I'm right at sea level too . And if memory serves , if the mixture screw is on the engine side of the slide ,it controls fuel . And if on the air cleaner side it controls air into the idle passage . If a idle air screw turn out to lean it out , if a fuel screw , turnin to lean it up . ( I think ! Carb basics 101 ... ).

Glenn

But the OKO just works so much better overall .... Just tell Chris to set yours up just like he did mine , (I'm sure he keeps detailed notes ) and you'll be a happy camper !

Edited July 9, 200917 yr by axulsuv