Got my new 2003 ZRX1200 carbs today!

[Diskman01]

woot! My new carbies arrived! Saw the thread on the Kawasaki 1200 carbs and I found a nice new 2003 ZRX1200 set on ebay for $175. They have ben re-jetted already for a 1200 with K&N pods and free flow exhaust and they have the allen bolt kit installed. Man are they clean! The look like a much more modern version of my 1978 E carbs. Will have to install the vacuum port for the timing advance, but overall it looks like a nice swap. I can FINALLY replace my worn out Mikunis. Will do the swap next week when I have some free time. I see they have a throttle position sensor too.. The electronics wizard in me likes that. I should find a use for that somehow.

Will post more pics and a performance review.

It SHOULD be well worth my 175.

Air inlet side.



Engine side

[donebysunday]

I have not kept track ? What does this mod do for you, HP, MPG or ?

Thank You ! Done };~)

[XSRAY1100]

I'll guess...

I think both and the advantage of more modern carbs to make parts hunting easier.

[Diskman01]

Parts availability, slightly better MPG (not what I need), and a better mid-throttle response from what I hear.

Plus, they are a quarter century NEWER design. My current carbies need a complete rebuild. Heck, for less than parts and my time to completely rebuild my 78's, I got current technology carbs that are pretty much a direct bolt on.

I have spent more money on stupider crap in life. And, if they don't work out, I will just re-list em on ebay or locally on Craigslist.

[TADracer]

They have ben re-jetted already for a 1200 with K&N pods and free flow exhaust and they have the allen bolt kit installed.

Even though they are jetted for a 1200 you might still need to do some tinkering with jets since the 2003 ZRX motor is much more efficient than our old XS motors. Not sure what jets are in your carbs but I am currently at 138 mains and 45 pilots in my 79SF machine which has pods, 4-1 header, re-timed cams and some light head porting.

Good luck and I know you will enjoy this mod when you are done.

[Diskman01]

Even though they are jetted for a 1200 you might still need to do some tinkering with jets since the 2003 ZRX motor is much more efficient than our old XS motors. Not sure what jets are in your carbs but I am currently at 138 mains and 45 pilots in my 79SF machine which has pods, 4-1 header, re-timed cams and some light head porting.

Good luck and I know you will enjoy this mod when you are done.

Thanks!

My 78 with pods and 4 into 1 is running factory jets. I fiddle with the (plastic) float heights on the old Mikunis to adjust now. The new carbs, I hope are close enough till I rebuild the engine this winter. I haven't pulled the bowls off the new carbs to see what jets are in there yet. Maybe this evening.

[BA80]

Not sure what your going to do about the vacuum for the advance since it's ported.

[Diskman01]

There are undrilled vac ports in the new carbs. I just need to drill a small hole and insert a nipple in #2.

[motoman]

There are undrilled vac ports in the new carbs. I just need to drill a small hole and insert a nipple in #2.

........maybe. If you caught BA80's last key word.......ported. Has to be ported vacuum, not manifold vacuum. In other words, the vacuum port needed is blocked off by throttle plate at idle.....no vacuum draw.

[drubuntu]

Me too!

Over the next couple weeks, I'll be making the same upgrade to my '80 Special. Good deal you found there, I found some '02 ZRX carbs for $200! Pods and 4-1 pipes in the mail...

[yamahansolo]

I just left the vac advance off. No harm. Pulls like a mofo and I've gotten up to 46 mpg. The zrx jets are too lean. Go with 138 or 140's these old bikes need a lot of gas! But yes you can drill the hole at a funky angle. There is a photo from a few years ago somewhere on here.
I've been running them for years with no issues.