Kawasaki kz400 - mini superbike

In reply to twentyover :

Not sure on manufacturer I'd have to see what the logo says but it's an OEM exhaust.

I also imagine they are fairly quiet. In fact I'm hoping that's the case.

Got a couple more items checked off the list.

Headlight mini relays and mini toggle switch were wired into the harness. Essentially the wiring harness is complete and ready to wrap but I'll wait until the bike is running just in case I need to troubleshoot.

Spark and timing appear to be good to go.

Brake caliper seals are here and hopefully this evening I can confirm they will work for my application.

New brass for needle jets, jet needles, mains, pilot, and air correction should be in my mailbox when I arrive home. I'll probably try to get them all in and see if the bike will fire up but hesitant to rush the process.

Another late to the party commentator

My brother had one of these that I rode extensively. I loathed it.......mostly because it wasn't an RD350.

The styling on them was always cool.

Love what you are doing with it. I expect it will be fun to ride.

In reply to Tom1200 :

I tried the 2 stroke world for a minute and was never a fan of the power delivery. Probably something I could have gotten used to but never did.

Out of the box these are okay, but with a little effort can feel pretty sporty. I'm hoping when I put some miles on it that the bug to ride is still there. I'm afraid it's just something I used to like and now is purely nostalgic.

In reply to captainawesome :

I flogged my brother's poor bike; routinely dragging the pegs through corners.......even on the crap stock suspension and tires.

It wasn't a bad bike it was just so much slower than the RD as well as being 50lbs heavier.

Well crap.

The brake caliper seal gamble didn't pay off. It was too small ID and after forcing things together I destroyed the seal. I wonder if I had soaked it in brake fluid if it had swelled up enough to work? Won't know now but I ended up ordering the overly expensive seal like I should have before.

Now I'm a hair under $100 in a brake seal situation which sucks. Really sucks.

After that ordeal I decided to call it a night but thinking about going back in the garage to clean up my mess from both the brake fluid and wiring job over the weekend. That usually inspires me to get more work done of which I still have plenty left to do including swapping out jets and syncing carbs.

In reply to captainawesome :

I'm thinking it's time to upgrade the caliper.......I am thinking you need a dual disc brake set up to go with the mini Superbike theme

In reply to Tom1200 :

As much as I want to do that, it would just cost more than I want to throw at the problem right now. On top of that figuring out what I need to make it work easily.  Two calipers, different fork legs, potential axle and spacer work, another rotor - possibly two if offset needs adjusted, a different master cylinder to match the dual piston setup, and a different brake hose arrangement. Then there's the consideration that it will probably add weight/complexity with not a huge benefit. I've considered at least upgrading/adapting the single caliper setup but it still shares most of the same problems or cost I'd face. Right now the easy button is a stupid expensive piece of rubber and it gets me on the road quicker. I'm definitely choosing easy button, I just wish I listened to my own advice to bite the bullet and buy the expensive one first, to save myself more cost and trouble.

Got most of the jets and stuff swapped over with only the needle left to tinker with this morning. Tomorrow night I'll try and get them synced up and ready to rip if time allows.

Current jetting setup for the vm30 carbs:

6F9 jet needle - middle clip

P-0 needle jet

25 pilot jet

180 main jet

1.0 air jet

I'm hoping this gets me in the ballpark. I've got another pilot jet and lots of mains to go up or down.

In reply to captainawesome :

Hey, Cap! Nice bike!

In the past, I've had good luck with the local industrial parts supply houses on finding oddball seals and such. May be worth a look next time. 

In reply to Recon1342 :

That was my initial plan but I am strapped for time these days. Now that I'm looking back it would have been time well spent, but c'est la vie.

i'd be searching rockauto for rebuild kits for 41 mm piston calipers.  IDK how much different the seal groove depth might be between automotive and motorcycle, but i'd be kinda willing to bet they're the same.

might also check with Wilwood, Brembo, StopTech, etc.

In reply to AngryCorvair (Forum Supporter) :

I think that some rear VW calipers may have something that could work, but the cost to find out was more than I was willing to gamble on. Granted I only spent half a day looking so there may have been some more in detail specs I could have found that may have worked.

Spent too long swapping needles and adjusting the throttle cable to not only sync both but not bind when releasing. Also spent 30 seconds oiling the air filters.

It's basically ready to start and instead of filling with fuel to try that out I decided to go back inside. It's getting late, I'm tired, and don't feel like smelling of fuel. Tomorrow I shall hopefully kick it to life for the first time under my ownership.

IT'S ALIVE!!!!!

No choke needed at around 70 degrees.

Needed a couple throttle squirts to get it to fire.

Idle is high but I didn't fiddle with any adjustments at all until this morning. I was able to get it settled into a nicer idle with some quick fiddling but need to be in less of a hurry to resync both carbs once idle is set.

It sounds really good. I expected quieter but think it will be close to whisper quiet with a helmet on. May end up wanting just a smidge louder if that's the case but for now I'm not worried about it.

Throttle response is great, no stumbles or hiccups but it's also not under load. All in all I'm stoked it's running well enough that I can start the fine tuning process.

The new brake seal should be here Saturday so maybe I'll be able to run it up and down the block?

Feels good to have it running and it's ignited my desire to finish it. YEEEEEHAWWWWWW!

First start video:

After warming up a few high RPM blips of the throttle:

Sounds great!

in reply to captainawesome:

today you have truly earned your screen name

It does indeed sounds awesome!

It looks and sounds great.....well done.

Idle has been set. Carbs synced. I took a video of it idling which is below, and then adjusted it a bit lower after that.

After getting that done I tightened various bolts. Adjusted the rear brake so it would actually work, then tested to make sure I had the clutch adjusted properly. Clutch felt great on release.

So I decided to just ride it a half block gently to feel it roll with a smidge of throttle. Tip in feels great, no sputter when warm. I didn't rev high at all with only the rear brake functional, no helmet, no jacket. It rolls and feels great so far though?

Brake caliper seal should arrive today. I have plenty of time carved out tomorrow to get it bleed and do a quick bolt tighten check. Gotta mount the license plate. The list is shrinking!

DEAD COLD one kick start settled directly into an idle this morning. Like a top. Couldn't be happier about that.

i love it.  that's a neat little bike.

It's annoying to think it was only a few minutes of work away from a running bike for months, but I wasn't ready to mess with it. Really jazzed on it again which will be a nice break from other projects for a week or two.

Did another cold start video when I got home. You can hear it bog with a little throttle which of course is because it's dead cold. Rain is here. Brake seal is here and looks legit. Tomorrow hopefully we ride!

The brake saga has been sorted! The new seal looks and fits just like the OEM one. I still had issues getting the caliper to bleed however. I noticed that the caliper seemed to not be centered with the rotor which seems weird. The axle spacers are all correct. But I have taken the rotor stuff all apart to paint. I noticed there's a thin spacer between the hub and the rotor that might just be in the wrong spot. After checking the parts diagram, it was confirmed. I'm a dope. A dope with BRAKES!!

After putting the spacer on the outside of the rotor we have proper alignment. Within a few pumps the piston was finally able to push out properly and the lever got firm. Heck yeah.

I grabbed my armored jacket and helmet to take a proper maiden voyage. The first trip was just around the neighborhood with maybe a top speed of 60 but mostly in the 30-45 mph range for about 15-20 minutes round trip. Some stop and go, some curvy roads. One of my biggest worries was the wheel lacing being wobbly or have vibrations. None of that was found. Idle is set a hair too low but I suspect there's a pilot mixture adjustment that will help.

My second trip I ventured further to the interstate. There's about a 2 mile run to the next exit. Higher revs it pulls fine but seems unhappyish at 1/4 throttle. It was super windy so that didn't help. Still no vibrations from the wheels which is helping build some confidence. Not sure my top speed on my run back but maybe around 80ish to 90 would be my guess. No tach or speedo currently on the bike which is on the short list. This trip was about 30 minutes and trouble free.

All in all I'm really pleased with how the bike behaved with a few items to address.

The front forks are too soft with way more dive on front braking than I prefer. Also the left fork lower bolt seal is leaking which is far from ideal. I'll need to replace both at some point. It may be time to consider some aftermarket springs and cartridge emulators. Or just use thicker weight oil and preload the springs a bit.

I think the oil sensor has a slight leak at the crush washer so I'll need to replace those.

Definitely need a speedometer. I have a couple bicycle speedos to choose from but I'm considering the Trail Tech Endurance. If I was racing I'd worry more about the tach but I'm not so may just do the speedo.

Jetting wise I don't know if I'm rich or lean so didn't push the bike hard. Next step will be to set the mixture screw via the dead cylinder method and then start reading plugs. Dialing in the 1/4 throttle area will be first and then at some point get into the mains to finish it off. I've ordered a dozen plugs to start the tuning process but they won't be here for a few more days.

Rear shocks feel good. The factory preload is where I left it so at some point I'll see if it needs adjusted.

It feels great in the corners but still haven't pushed it hard.

Highly recommend some springs and emulators if you are heavier than like 160lbs. Fork oil does do wonders with some preload tho. 

I am about to pull my stock stuff off my sv650 to put a trail tech on it here soon. I have installed many and absolutely love them. 

In reply to Professor_Brap (Forum Supporter) :

I've run Progressive springs before but typically emulators use single rate. Need to see what my options are again, it's been years since I have gone down the rabbit hole.

Good to know about the Trail Tech. I've read good things about them and there doesn't appear to be any thing comparable that I've found.