Super moto power with kz550 engine (project)

[klx678]

Are the carbs smooth bore or are they the OEMs from the KZ?

By the way, this looks way too fun...

[nelson8708]

Are the carbs smooth bore or are they the OEMs from the KZ?

By the way, this looks way too fun...

I was told they were TK22 carbs...stock as far as i know

If you're running the stock airbox, I'd stick with the stock breather system unless you are very careful with hose routing to prevent water contamination from rain and washing.

I'm running pod filters. Either going to throw a hose on it and run it to the bottom of the frame for throw a breather on it.

Still waiting on the micro drill bit kit to get here. In the mean time i'm going to shim the jet needle up about a 1/16" once i figure out how to get them out of the carbs.

[Bill Frazier]

Drilling jets to a larger size can cause problems. Jets are reamed to a certain size, not drilled. Drilling leaves tool marks which can cause the fuel to swirl, slowing it down and making the jet act like a smaller size. Two jets drilled with the same drill may even pass different amounts of fuel.
You might be better off just buying new jets of the correct size. I've bought them for my bike from internet sellers for less than $8.00 each.
Just a thought from an old machinist.

[nelson8708]

they aren't any aftermarket pilot jets that i have found for my carbs, so for them its not really a choice. As far as the mains go i found that KEIHIN Main Jets will fit and i can get them for 3.50$ each local. The drills are for getting in the general ball park of what size jets i need then i'll go buy a set. When i buy jets i can pretty much assume that even if the diameter hole is the same that they would flow a little more than drilled ones. Thanks for the info

-Nelson

[nelson8708]

She is running on all 4 cyl now. I drilled out my pilots to a 37 and drilled my mains to a 99 (biggest drill i had). Air screw is 1.25 turns out. When I rev it up the rpm seems to hang a little high before it drops back down. Do i need to turn in or out the air screws?

I got to ride her around the block and all the gears are there and the clutch works fine. I'll get some vid of it this weekend if it doesn't rain the whole time.

On a sad note one of the guys (Chris Pollak)that i took the trip to the dragon with passed early this morning from injuries he sustained in a motorcycle accident. He was in full gear when it happened. When ever you suite up remember to keep it safe.

[RichLockyer]

On my WR250F, a hanging idle is a sign of a lean condition... go 2 turns out and see if that helps or hurts.

[nelson8708]

I rode her today to try to work on the hanging idle and after messing with the pilot screw i found my self 1/2 turn out(closed is richer and turning out is leaner). I'm guessing that means i need to up my pilot jet, no? If so how much bigger should i go (37 currently)? No cracks in the intake boots and every thing is capped off.

Here is a vid of me just rolling down the street.

YKZ550 putting around - Car Videos on StreetFire

[RichLockyer]

I always move the pilot one "step" (normally two numbers) at a time.
You want to be between 1 turn and 3 turns.

[nelson8708]

Lately i've been busy working on my car (sold my ka swap and going to throw a SBF 302 in there and boost it), but i finally put a little time in on the bike. I went and got some more supplies to finish my sync tool and got a few drill bits so i can increase my main jet size. As of now i have a 40 pilot jet and a 106 main jet. Tomorrow i plan to sync the carbs (attempt # 2) and get the stuff needed to make the choke fast idle adjustable (thanks loudhvx). Earlier today when i adjusted the float level as best i could (time consuming as hell and my first timing do it). After that i took out the plugs to take a look at them and seems like #1 was running lean compared to the others and that is the one i had to raise the float level the most. I hope tomorrow goes well and i should be able to get on her a little bit (past 1/8 throttle) fingers crossed for tomorrow

[QKENUF4U]

if its hanging on idle then its LEAN (in your case your going to go IN with the pilot/air screw to richen it up-airbox side of carb so it controls AIR in the circuit. ..)

y didnt you just do this instead of messing with drill bits etc...
80-82 Kawasaki KZ550 LTD Dynojet carb jet kit stg 3:eBay Motors (item 370143962516 end time Nov-08-09 14:31:36 PST)

[danielroca]

y didnt you just do this instead of messing with drill bits etc...
80-82 Kawasaki KZ550 LTD Dynojet carb jet kit stg 3:eBay Motors (item 370143962516 end time Nov-08-09 14:31:36 PST)

You know as i continued reading down this page I was going to suggest this exact same thing. There are a few people on ebay selling out these kits.

Kawasaki Z 500 KZ Z500 KZ500 Carburetor Carb Jet Kit:eBay Motors (item 330365231775 end time Nov-02-09 14:16:15 PST)

these guys will even discuss with you everything else your modding on your bike including your altitude to help you get the best results.

[nelson8708]

$$$$ + i dont know if they have the right size jets for me.....needles will probably come next year in a K&L rebuild kit

With the bigger jets and sync'ing the carbs she runs nice...still need to work on my pilot screw setting. Just picked up forza 3 so probably wont be getting much done on either project for a week or so

my gamer tag is nelson8708 if you guy want to get your *** handed to you

YZ550 - Car Videos on StreetFire

[gbaronetxcr]

Agree hanging idle is definitly lean.

Cool project.

[sebastian1000]

Good thread. I love watching builds like this come together.

[Cucco]

crazy motorcycle!!!!!!

but in italy there worse..


http://4.bp.blogspot.com/_i_AovfzNXg...0/vespa750.jpg

[QKENUF4U]

as a bike tech ive done a TON of stage 3 kits and 80%+ of the time you never have to change your pilot... sometimes they give you one and it causes PROBLEMS......
as for the kit not having your jet size..... its a stage 3 jet kit for EXACTLY that mod to that motor, so it will have the size you need. no drilling things out and HOPING you didnt go to big..... plus the needles are prob. a different shape to help in all ranges of fuel delivery/rpms....
just makes sense to me to start there and add a set of jets if needed.....they give you a VERY GOOD baseline to start with instead of guessing at every step like you are now...... plus without a dyno/ega your only gonna get it close .... not perfect..
plus running 4 individual pipes is gonna be a tuning ***** for ya also....
not my cup of tea sound wise but hope ya got good ear plugs....
good luck

[nelson8708]

New vid....mostly a build vid from start to finish but, there is a new part with me ripping on it a little after picking it up from my uncles house today to bring home.

YKZ550 build vid - Car Videos on StreetFire

let me know what you think

-Nelson

[QKENUF4U]

im still tryin to figure out why bother other than to be different... put a set of 17's with big A&& brake up front on this bike in 2-stroke form and it would destroy the 550 up till prob. 60mph..... or plop a yz490 motor in place....
but to each their own. glad things are working our for ya and you had fun building it....

[nelson8708]

why bother other than to be different...

You hit the nail on the head....i dont like doing the same as everyone else. Most of the time its about speed but, not always.

[QKENUF4U]

so a yz490 motor isnt fast enough ? or different enough ? hell plop a cr500 motor in there and youll def. be different and more than fast enough.. lol