My 2007 is running a tad lean on top with a Keihin 125 MJ. I'd like to go to a 128 but my patience is low for waiting on new jets to arrive.

I also have a DJ 120 MJ which equates to a Keihin 128.

Has anybody mixed-n-matched the 2 or is it a big no-no due to the difference in needle profiles between the N1TC and the DJ needle?

 

I doubt it would matter. Give it a shot.

 

Go for it. If the jets have the same size opening they will work the same regardless of what needle you are running.

 

The DJ 120 main with the DJ needle seems to be the perfect setup for my 06.

 

Have you tried moving the needle clip down one notch? That might help richen the top end.

 

Thanks everyone.

cmott - I really think it's the MJ because it's good on bottom, mid, and mid-upper rpms but fallls a little flat on plain old top end.

Most report the N1TC needle being right on at clip position #2 rather than #3 and the bike seems to still run well in that 1/4 - 3/4 throttle region where clip position would dominate.

All in all, I think I'll try the DJ120 and if it doesn't take care of it - I'll change clip position. Too bad it's not the other way around - much easier to pull the needle with the carb in place.

 

I recently change main jet with the leave the carb on the bike method. It was quicker but my float pin fell out. Just keep an eye on that pin and you will be good. Just loosen the clamps, remove screw holding the throttle cable and disco the cable. Rotate bottom of carb out and remove float bowl. No need to even mess with the fuel line. Oh and drain the float bowl before you rotate the carb.

 

let the pin slide out one way a hair and wipe a little grease on the end, it'll keep it in place putting the bowl back on

and for those that didn't know there is a bowl drain valve you can open.