Author Topic: The Mosquito! (Kawasaki KZ250)  (Read 47258 times)

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Offline Scott S

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Re: The Mosquito! (Kawasaki KZ250)
« Reply #100 on: May 12, 2011, 07:46:56 PM »
Looks great...a ton of fun in a three hundred lb package!

 Actually, stock was less than 300lb. I think I must have cut another 20-30 off that. I plan on weighing it soon.
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Offline Retro Rocket

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Re: The Mosquito! (Kawasaki KZ250)
« Reply #101 on: May 12, 2011, 10:02:26 PM »
How comfortable are those rear sets.? They look way  too low and too far back.....
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Offline Scott S

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Re: The Mosquito! (Kawasaki KZ250)
« Reply #102 on: May 13, 2011, 07:02:14 PM »
 They're actually pretty comfy. I'm 6'1" and certain things had to go in certain places, if you know what I mean. This is a VERY small bike to begin with. They are no lower than the stock pegs, just further back. 
 I'll see if I can get some pics with me on the bike soon.
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Offline Scott S

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Re: The Mosquito! (Kawasaki KZ250)
« Reply #103 on: May 27, 2011, 05:02:00 AM »
 We did a little work on the rear brake. We were warned that the linkage we had fabbed up may be robbing us of some leverage. They were right...

 We did two things:
 1) Made a longer arm to be welded to the outside (with several holes for adjustment)
 2) Drilled a lower hole on the inside arm of the pivot.

 Doing these two things gave us back the leverage we needed. Excellent pedal feel and I can actually lock up the rear brake if I wanted to.
 I may trim of the extra length on the outside arm, but leaving it there would provide adjustment for a future owner who may have shorter legs than me. There is also adjustment left in the rear set foot pegs, so the bike could be configured to fit a range of riders.


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Offline Scott S

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Re: The Mosquito! (Kawasaki KZ250)
« Reply #104 on: May 27, 2011, 05:05:54 AM »
 Forgot to mention: I think we will adjust the brake and shift lever up just a tad. (Just the levers, not the pegs) I don't think I stand a chance of ever dragging either one, but if I leave my toes below the shift lever or have the rear brake on while making a RH turn, my feet/toes get a little close to the pavement.

 Again, if I weren't so long legged and the bike wasn't so small, the pegs could be moved up. It is what is is, though and nothing but the tires have touched the pavement so far....knock on wood.
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Offline Scott S

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Re: The Mosquito! (Kawasaki KZ250)
« Reply #105 on: May 27, 2011, 05:14:48 AM »
 Took it out for a ~25 mile shake down run and discovered a few things....

 A) It's LOUD! The home made baffle sounds mean and surprisingly deep for such a small bike, but I'm going to find the correct baffle for the stinger we used to make the mega-phone.

 B) It vibrates like crazy. I need to replace a few lost nuts with nylon lock nuts and apply some blue lock-tite liberally to a few others.

 C) It's very lean. Scarily lean. It never acted like it wanted to seize up, but my I.R. temp gun gave me readings of ~300 degrees on the cylinder when we got home and the spark plug is very white.
  I did figure out that the carb is from an RD series Yamaha. I have a friend who is a 2-stroke guru and will ask his opinion on clip setting for the needle and maybe raid his parts bin for a larger main jet.

 I got her up to 78 MPH and the tach showed a little over 7,000 rpm. Factory literature says max HP is at 9,000 rpm, so I either have an aftermarket tach that is reading off a little or she just plain ran out of gas.
 I'll get some more fuel in the carb and try again, but I feel like it'll do 80+ eventually.

 Oh, we also weighed it using the bathroom scale method and she's just over 250 lbs.

 Some pics from the shake down run (I'm still waiting on my tank badges).


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Offline Scott S

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Re: The Mosquito! (Kawasaki KZ250)
« Reply #106 on: May 27, 2011, 05:18:55 AM »
In the above pics, you can see what I mean about the levers. I want to bring them both up to be a little more parallel to the ground and closer to the height of the pegs.

 Here's the spark plug reading....YIKES! I guess we got lucky on this ride. We'll definitely do some adjustments before any further riding.
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Offline Scott S

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Re: The Mosquito! (Kawasaki KZ250)
« Reply #107 on: June 27, 2011, 06:15:50 PM »
 Well, no need to worry about the exhaust being too loud. It cracked where we welded on the tab.
 I loved the look...hated the sound, though.
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Offline Scott S

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Re: The Mosquito! (Kawasaki KZ250)
« Reply #108 on: June 27, 2011, 06:19:12 PM »
Luckily, I had purchased a muffler for this project a while back, before I changed directions and went with the stinger.
 We simply cut the head pipe of, fabbed up a rubber mounted hanger and bolted it on.
 Because of some carb tuning we're doing (and waiting on jets, needles, etc.), I haven't been able to hear it yet. I DO have a buddy that has a CB200 with a pair of these mufflers and it sounds pretty good....and MUCH more quiet than the KZ250 was!

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Offline Scott S

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Re: The Mosquito! (Kawasaki KZ250)
« Reply #109 on: June 27, 2011, 06:24:06 PM »
 Here's another look at the muffler. Also in this shot, notice that we adjusted the pedal position on the brake and shifter levers. I had a few people voice concern over them being too low, but this is a small bike and I'm a long legged guy.
 I've been watched while riding it and I'm in no danger of dragging anything (if I'm leaning it that far over, it's too late anyway!), but my Dad did notice that the levers were the lowest point and may have put me in danger of catching my toes on something, especially when applying the rear brake. So, now they're a little more horizontal. And remember, these pegs are on the same plane as the stock pegs were.

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Offline Scott S

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Re: The Mosquito! (Kawasaki KZ250)
« Reply #110 on: September 02, 2011, 06:25:35 PM »
The Mosquito is doing OK. Sorry for the long pause between updates. It took me FOREVER to get the badges done. I actually had to retrieve them from one shop and found someone else to do them for me.
 They're not quite as bold as I would have liked, but they turned out OK, don't ya think?



 My only problem is that the silver prismatic background of the flags kind of clashed with the whit of the badges. They could both be white OR silver, but not mismatched, IMO. I'll probably look for some white/red flags for the side covers.
 This pic are a little washed out from the sunlight, but...

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Offline Scott S

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Re: The Mosquito! (Kawasaki KZ250)
« Reply #111 on: September 02, 2011, 06:29:40 PM »
 The muffler is doing and sounding fine, except for a hanger bolt that vibrated loose on the last ride. I've already replaced it and used a self-locking washer, but the WORST part of that ride was the throttle cable breaking.
 I THOUGHT I knew how to silver solder.....
 Even a 250 lb. bike gets heavy when you have to push it half a mile to get off the main road and into a driveway so you can use the cell phone.

 I was all set to try again using a solder pot when I found a throttle cable for a KZ200 that looks perfect and it was only $11.99 shipped. It's on the way and I'll let you know how that goes.

 Until then, more gratuitous shots...


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Offline Scott S

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Re: The Mosquito! (Kawasaki KZ250)
« Reply #112 on: September 02, 2011, 06:32:22 PM »
Oh, and forgot to add...after much jetting, I think I have the carb dialed in. Runs great with no stumbles. Oiling the filter helped a bunch. I may go down one more size on the main one of these days, but I want to ride it for a while first.
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Offline hoodellyhoo

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Re: The Mosquito! (Kawasaki KZ250)
« Reply #113 on: September 02, 2011, 06:37:57 PM »
Thanks for the update. The bike looks great! Any chance of a video with the new muffler?
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Offline Scott S

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Re: The Mosquito! (Kawasaki KZ250)
« Reply #114 on: September 03, 2011, 03:33:40 AM »
 I'll try...I've never uploaded video phrome my digital camera to the 'net before. Maybe I'll try hosting one on photobucket or something. May take a week or two until I have the time off...and the throttle cable gets here.
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Offline lucky

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Re: The Mosquito! (Kawasaki KZ250)
« Reply #115 on: September 05, 2011, 04:29:09 PM »
While I was working on that, my Dad was cleaning the piston, the rings, ring grooves and checking everything to make sure it was within spec. This engine still measures out brand new. It sucks that someone let it sit outside for so long.


Yes it drives me crazy too, to just see a motorcycle sitting with no cover and at least it could be all sprayed down with a can of WD40. Some people have too much money.

Offline Scott S

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Re: The Mosquito! (Kawasaki KZ250)
« Reply #116 on: October 14, 2011, 10:06:05 AM »
As requested, some vids of the muffler and a quick fly-by.
 It took a little work, but we got the KZ200 throttle cable to work. I'm going to take it out for a spin today and see what parts fall off next!

Kawasaki KZ250 cafe racer

Kawasaki KZ250 cafe racer fly-by
« Last Edit: October 14, 2011, 10:12:50 AM by Scott S »
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Offline 70CB750

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Re: The Mosquito! (Kawasaki KZ250)
« Reply #117 on: October 14, 2011, 10:29:23 AM »
The "before" pictures came out blurry, but here are some "during" and "after" pics of the carb. It was pretty nasty.
  I talked to Sudco and, best they can tell, it's an OEM carb. What model and for what bike...who knows? It's based on/closely related to a VM28. I also found a proper air filter that fits it and a manifold that will only take a little bolt-hole modification to make it work (NOT wrapping with duct tape!  ::)  )



Dumb question.  What is the purpose of the blue hose there?
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Offline Scott S

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Re: The Mosquito! (Kawasaki KZ250)
« Reply #118 on: October 14, 2011, 10:35:12 AM »
 Vents and overflows.
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Offline 70CB750

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Re: The Mosquito! (Kawasaki KZ250)
« Reply #119 on: October 14, 2011, 10:55:24 AM »
I should have asked diferently - are those two ports connected with the hose?
Prokop
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Offline hoodellyhoo

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Re: The Mosquito! (Kawasaki KZ250)
« Reply #120 on: October 14, 2011, 10:58:42 AM »
Sounds good 8)
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Offline Scott S

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Re: The Mosquito! (Kawasaki KZ250)
« Reply #121 on: October 14, 2011, 11:11:31 AM »
I should have asked diferently - are those two ports connected with the hose?

 No, they vent to the atmosphere.
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Offline crazypj

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Re: The Mosquito! (Kawasaki KZ250)
« Reply #122 on: June 14, 2012, 09:21:17 AM »
Got the tabs for the side covers welded to the frame.





 Have you checked the frame for flexing/cracks
The flat plate and angles probably makes a real good hinge?
« Last Edit: June 14, 2012, 09:24:27 AM by crazypj »
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Offline shawnlennon

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Re: The Mosquito! (Kawasaki KZ250)
« Reply #123 on: November 22, 2012, 09:30:41 AM »
I'm rebulding the same bike. Having trouble getting the cam chain off to remove the head.

Offline Scott S

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Re: The Mosquito! (Kawasaki KZ250)
« Reply #124 on: November 22, 2012, 02:46:19 PM »
 This bike is long gone. Sold it last year. But, to answer the last two questions...

 The frame showed no signs of cracking. It was welded professionally and all the way around the bracket. Seemed fine and very stiff.

 Shawn, can't you just unbolt the cam gear and slip the chain off?
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