|
|
Rank: MSF graduate
Groups: Member
Joined: 4/26/2008
Posts: 25
Location: San Francisco, CA.
|
Looking for a rebuildable set of CV30 Zephyr Carbs. Not sure yet, but I'm think the 615 kit and Megacycle Stage 3 Cams (not X3 Cams) might require more fuel than what my stock, but Stage 3 Jetted TK27 GPz550 Carbs can provide. I dyno'ed my race bike's stock engine, with K&N Pod Filters, Moriwaki Race Exhaust, Accel Cooils and Wires, NGK Iridium DPR9EIX-9 Plugs and Dynojet's Stage 3 Recommendation of: 134 Mains Stock Pilot(35) Needle Clip on #4 if 6 from the top Mixture Screws 3.5 turns out After the first dyno run, the Tuner recommended the following: 132 Mains Stock Pilot(35) Needle Clip on #6 of 6 from the top Mixture Screws 5 turns out I didn't have the 132 Mains with me on the second run the next morning, and I only turned the mixture screws 4.5 turns out, just to see what it would do. I could only afford the 2 runs. Here's the links to the first two: http://img.photobucket.com/albums/v97/CoreyClough/Track%20Bike%202009/GPzDynoBlackAndWhite1.jpghttp://img.photobucket.com/albums/v97/CoreyClough/Track%20Bike%202009/GPzDynoBlackAndWhite2.jpgHere's the second two: Fuel comparrisons from Stage 3 Setting to Dyno Tuner's Settings. Richened the fuel up to where he liked it. http://img.photobucket.com/albums/v97/CoreyClough/Track%20Bike%202009/GPzDynoBlackAndWhite4.jpghttp://img.photobucket.com/albums/v97/CoreyClough/Track%20Bike%202009/GPzDynoBlackAndWhite3.jpgEngine bottom end will be stock, and not rebuilt(low miles). Top end will have porting, Megacycle Cams(478-60 Grind) and Slotted Gears, with Stock Valves. I'll try the TK27's on the engine to break in this engine, and then take it to the Dyno to see what's happening. I might need to enlarge the pilot jets(dyno will tell), and up the main jets(have a bunch), to get the TK27's to work, but might need to upgrade the carbs, and can't afford the Smoothbores just yet. I'll be racing with AFM this year, starting in March. So if anyone has a set of rebuildable CV30 Carbs they would want to sell, let me know what you want for them, as I'll be looking to use them in the future. I've been looking on ebay, and haven't come across a set in months. Thanks, Corey
GPz550 Race Bike Stuff: http://smg.photobucket.com/albums/v97/CoreyClough/Track%20Bike%202009/GPz550 Pictures of Stuff I've Done: http://smg.photobucket.com/albums/v97/CoreyClough/Coreys%20GPz550%20Pics/YouTube Videos: http://www.youtube.com/user/CoreyDSFACorey San Francisco, CA (The Straight Part) AFM #944
|
|
Rank: Administrator
Groups: Administration
Joined: 4/23/2008
Posts: 222
Location: Catskill Mtns.
|
You may find the 30s are too big. I tried basically the combination you are working with, the serious business grind from Megacycle with a fairly normal race exhaust and the 615 kit plus the CVK30s. I ended up (regardless of cam timing) with a big 4-5k rpm rich spot that was still way too rich even when I leaned everything out so much the bike would barely run anywhere else. I went back to GPz stock cams and it was a lot better, with a bit less peak power. I think the smaller carbs work better with the bigger cams, since they help prevent the reversion that was causing the rich spot. I hope to eventually try out the Bassani exhaust, which has a serious anti-reversion design that should greatly reduce the rich spot when used with bigger cams and the 30mm carbs. Right now I am still trying to come up with the cash for prototypes to sell parts, and one of the prototypes is going to be the collars that allow me to properly install the Bassani system. If you want to play around with a set of CVK30s, I have a totally clean set, I think with a Factory Pro Config 10 kit installed, that I'd let go to you for $250 plus shipping (I'm in NY now). Let me know if you want 'em, and that is the friend price since you've helped me out a few times in the past. :) Wish I was in a position to ship them to you for free to play around with, but money's just too tight for me right now.
| 1990 Kawasaki Zephyr 615 (Daphne) -=- 1986 Kawa Ninja 250 (stolen) | | The Motorcycle Fuel Injection Handbook -=- http://tinyurl.com/297abo |
|
|
Rank: Administrator
Groups: Administration
Joined: 4/23/2008
Posts: 222
Location: Catskill Mtns.
|
Oh, and you might pick the brain of Michael Leister if you can find him. He ran GPz550s in Super Dino for many years and was one of the tops in the class before he stopped racing (I have his old race bike in my storage closet, in fact), and I'll bet he can save you some time and effort experimenting.
| 1990 Kawasaki Zephyr 615 (Daphne) -=- 1986 Kawa Ninja 250 (stolen) | | The Motorcycle Fuel Injection Handbook -=- http://tinyurl.com/297abo |
|
|
Rank: MSF graduate
Groups: Member
Joined: 4/26/2008
Posts: 25
Location: San Francisco, CA.
|
Thanks for the information Adam. Emerson (a.k.a. NoEardGoat on the GPz550 Site) is running the 615cc kit, stock ZX550 Cams and Sprockets, and the CV30 Carbs. He doesn't ride his much, but that combination seems to be working for him. AFM Racing next season and looking to get this engine broken in before the first few rounds. If I dare venture into the CV30 Carbs, I'll be buying that set from you, if it's still available. I know money is tight, and wouldn't ever expect anything for free. For now I'll work with the TK27's, fattening them up as much as needed. Oh and a dyno posting will be in the works as well. Thanks again for the info and reply. You need to change your location. 
GPz550 Race Bike Stuff: http://smg.photobucket.com/albums/v97/CoreyClough/Track%20Bike%202009/GPz550 Pictures of Stuff I've Done: http://smg.photobucket.com/albums/v97/CoreyClough/Coreys%20GPz550%20Pics/YouTube Videos: http://www.youtube.com/user/CoreyDSFACorey San Francisco, CA (The Straight Part) AFM #944
|
|
Rank: Administrator
Groups: Administration
Joined: 4/23/2008
Posts: 222
Location: Catskill Mtns.
|
I keep forgetting that people are running around with the stock airbox still in place, and that makes all the difference in keeping the intake from being too short and too unrestricted. :P You likely will find that the 30s give you something with big cams and the stock airbox still in place.
| 1990 Kawasaki Zephyr 615 (Daphne) -=- 1986 Kawa Ninja 250 (stolen) | | The Motorcycle Fuel Injection Handbook -=- http://tinyurl.com/297abo |
|
|
Rank: MSF graduate
Groups: Member
Joined: 4/26/2008
Posts: 25
Location: San Francisco, CA.
|
Thanks again Adam. I'll keep you in mind if and when the time comes. Let me know before you have to list them on Ebay. Emerson gave me all of his extra main jets he had, going from 134-142, but I doubt I'll ever need anything past 138. What jetting are/were you running in Daphne?
GPz550 Race Bike Stuff: http://smg.photobucket.com/albums/v97/CoreyClough/Track%20Bike%202009/GPz550 Pictures of Stuff I've Done: http://smg.photobucket.com/albums/v97/CoreyClough/Coreys%20GPz550%20Pics/YouTube Videos: http://www.youtube.com/user/CoreyDSFACorey San Francisco, CA (The Straight Part) AFM #944
|
|
Rank: Administrator
Groups: Administration
Joined: 4/23/2008
Posts: 222
Location: Catskill Mtns.
|
I'll have to dig out the carbs and check. Keep in mind, though, that main jet and needle length/taper go hand in hand, and I'm using some crazy needle from the Factory Pro collection (they have about 20x as many needle sizes as are in kits to facilitate developing new kits), so the main jet number wouldn't necessarily translate to a similar engine with different needles.
| 1990 Kawasaki Zephyr 615 (Daphne) -=- 1986 Kawa Ninja 250 (stolen) | | The Motorcycle Fuel Injection Handbook -=- http://tinyurl.com/297abo |
|
|
Rank: Administrator
Groups: Administration
Joined: 4/23/2008
Posts: 222
Location: Catskill Mtns.
|
I did dig out the carbs from my storage, and they are clean CVK30s with a Factory Pro Config 10 kit already installed. You'd want very different needles from ones used with a stock motor and airbox, though. I can take out the Config 10 needles and main jets and keep those for a future project since I doubt you will have any use for them. mg15 from the GPz550 board also has his eye on that set of carbs, and I do only have one set right now... One thing I forgot to mention -- if you have to go more than 3.5-4 turns out on the idle mix screw, your pilot jet is too small. Best would be the next size up pilot jet, if available, and dropping the needles back down a bunch of clips, which should give you the same results except it will be slighthly richer as it comes on the needle. More than 4 turns out on the idle mix screw makes for inconsistent fuel droplet size at closed-throttle cruise and idle, and hurts power and fuel economy as well as smoothness. Further, there's often not enough spring tension when the screws are turned out that far, so vibration can now cause the settings on the idle mix screws to "creep" to richer and richer settings, until the screws actually fall out at which point that cylinder won't run at all. If you are constantly going over your carbs as you might be in a race environment, this may not be an issue for you, except the tansition between trailing throttle and on throttle might not be as smooth as it could be.
| 1990 Kawasaki Zephyr 615 (Daphne) -=- 1986 Kawa Ninja 250 (stolen) | | The Motorcycle Fuel Injection Handbook -=- http://tinyurl.com/297abo |
|
|
Rank: MSF graduate
Groups: Member
Joined: 4/26/2008
Posts: 25
Location: San Francisco, CA.
|
Thanks for the information Adam. I have been conversing back and forth with Weston Orloff of MOMBA2, and they are using carbs from an '85-'87 ZX600 with great success on their 615cc racer. I started looking for CRs and Smoothbores through my contacts, and neither Sudco, nor Mikuni has anything that they can sell. They use to sell a complete kit years ago, but not anymore. Those that have a bike with these carbs on them, cherish them. Anyhow, I'm not running the stock air box, and never plan on it. K&N Pod Filters on all my bikes. What you state about the throttle being a little choppy makes sense. I can feel it when I roll off the throttle, and roll back on over 6000 rpms. There isn't a next size up pilot jet, so I'd have to drill mine out and test from there. I have a few TK27 Carbs, and many stock pilot jets, so I'm not worried about going too far, but will go one drill size at a time. I've stretched the springs a little for the mixture screws, and that has more tension, but I completely understand what you mean about the possibility of them backing out with engine vibration. I do have a new Motion Pro Sync Tool, and it's excellent. If anyone is thinking about vacuum syncing their carbs, just do it. Makes all the difference in the world. As for the CV30 Carbs you have, they would work well with my older 615 kit I plan on running in one of my street GPz's with stock cams, Accel Coils and Wires, iridium Plugs, and Pod Filters, with a 4-1 exhaust. E-mail me the information, and specifics on them please. First race with AFM is in 2 weeks at Infineon. Fabbing a belly pan this weekend, like MOMBA2 has, and finishing safety wire drilling the necessary bolts.   Thanks again for the info Adam. Never could locate Michael Leister.
GPz550 Race Bike Stuff: http://smg.photobucket.com/albums/v97/CoreyClough/Track%20Bike%202009/GPz550 Pictures of Stuff I've Done: http://smg.photobucket.com/albums/v97/CoreyClough/Coreys%20GPz550%20Pics/YouTube Videos: http://www.youtube.com/user/CoreyDSFACorey San Francisco, CA (The Straight Part) AFM #944
|
|
|
Guest |
