Carb Rebuilding Service

Hey Guys!  time to come out of hibernation, and start prepping for the riding season (still a month away)..
I spent all last summer banging my head against these Keihin carbs, and i managed to get them sorted enough to run, but it was never rideable. 
it's fine from idle to mid throttle, but accelerating, under load, I lose power, which feels like a fuel starvation issue.

I remember seeing a website for a guy that "specializes" in these carbs, and offers a rebuilding service, but for the life of me, i can't find it now.
I've also flirted with the Mikuni VM30 kit from Speedmoto.  I have lots of history with Mikuni carbs, but i'm hesitant to drop $400, based on the horror stories i've read.

Thoughts?

Here's a video of it it running, after i replaced the mufflers




 

Where is the airbox?  The bike won't run for $hit without it unless you totally rejet the carbs.

You need a stock airbox, Cv's and pods can only run with a compromise, you have to sacrifice power somewhere with them. 

It's sounds like it's not jetted right. Get your self a 6 sigma jet kit . I put one in mine recently because it was blubbering and running terrible, now it runs perfect and doesnt miss a beat. Just search 6 sigma with your model of bike on ebay and it should pop up. Just add the information he ask for like year, make, model, your location, and any mods you have done like pod air filters and he dials in the jetting to suit your needs. It was a total life saver for me. 

in regards to the air box, my bike didn't have one when i got it. 
In order to cobble together working carbs, i picked up a parts bike, and it has an air box, but as of now it's completely useless, since it doesn't have the carb boots.

I have lots of experience jetting Mikuni carbs, but these Keihins are a nightmare.  it's so hard to find reliable information, let alone parts.
I purchased a jet kit when i rebuilt them (from Z1), and i later read reports that they aren't reliable...
i can easily get any mikuni jet i could ever need.  (Bob's Cycle is next door to my office, and Dennis Kirk is an hour away).

wrote:

It's sounds like it's not jetted right. Get your self a 6 sigma jet kit . I put one in mine recently because it was blubbering and running terrible, now it runs perfect and doesnt miss a beat. Just search 6 sigma with your model of bike on ebay and it should pop up. Just add the information he ask for like year, make, model, your location, and any mods you have done like pod air filters and he dials in the jetting to suit your needs. It was a total life saver for me. 

Thanks for the recommendation...

Wiredgeorge motorcycle carbs

or pm ED   Nessism    who posted above

Dave

wrote:

Wiredgeorge motorcycle carbs

 

That's exactly what i was looking for.
Thank You!

I've rebuilt at least half a dozen sets of Keihin CV34's that are commonly used on the 4 cylinder KZ750's.  They are a little more difficult to work on than BS CV Mikuni carbs, but by no means are they difficult to work on.  Mind you, when I rebuild carbs I take them back to stock jetting.  I'm NOT a pods guy, and I can't offer any jetting advice other than to say don't use pods, OR, get a Dynojet kit.  

Regarding Wiredgeorge, I know he's knowledgeable, but either the guys working for him suck, or he's slipping, because I had two different guy send me carbs that he worked on and both were in horrible condition.  More specifically, he media blasted the bodies and there was glass bead grit all through the inside.  Plus, he blasts all the zinc plating off the steel parts so you can expect them to rust afterwards.  

Read this if you want to go in another direction for less money :

www.kzrider.com/forum/11-projects/611489...ling-kz400-s?start=0

 

wrote:

 Mind you, when I rebuild carbs I take them back to stock jetting.  I'm NOT a pods guy, and I can't offer any jetting advice other than to say don't use pods, OR, get a Dynojet kit.  

Regarding Wiredgeorge, I know he's knowledgeable, but either the guys working for him suck, or he's slipping, because I had two different guy send me carbs that he worked on and both were in horrible condition.  More specifically, he media blasted the bodies and there was glass bead grit all through the inside.  Plus, he blasts all the zinc plating off the steel parts so you can expect them to rust afterwards.  
 

I use the same approach, and that's exactly why i went with the kit from Z1 initially. 
The condition of the carbs was terrible when i started.  the jets were either too beat up to identify, or missing all together.  i wanted to get to the original baseline, and make adjustments from there, provided i couldn't source the factory airbox. 

Thanks for the info on WiredGeorge.  They've already been cleaned fully, and I would never want them to be blasted/stripped.
all i want is jetting.   I'm going to try the 6Sigma kit as previously recommended.

wrote:

Read this if you want to go in another direction for less money :

www.kzrider.com/forum/11-projects/611489...ling-kz400-s?start=0


 

Interesting read.
If i was planning on keeping this bike long term, i'd definitely look into the HEI upgrade, and Chinese VM30
Realistically i only bought this bike to save it from the kid with Cafe aspirations.  it was in too good condition to suffer that fate.
I have a long term project in my XS1100, and i have a Maxim on the way (once the snow melts).  I just want to be able to enjoy this bike while i have it, and be able to pass a good running survivor on to the next guy when the time comes.