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Also if you have tensioned you chain unevenly it can cause a wobble if the wheels are not on the same plane.

Also you dropped forks how much through the triple trees and possibly raised the rear of the bike? That would make it very twitchy and unstable at higher speeds. Front fender or fork brace is another must have.

An old school test for a bad rear tire induced wobble is to overinflate to about 34-36psi and try it up to around be 45 mph. Then deflate it to about 20psi and try it again to see if it is any better.
Sometimes if a crappy tire,
an over inflated or underinflated tire cause the wobble to get worse or better.
Just be careful when testing.
Seriously though, if those tires are more then 4-5 years old, don't waste any time with them.

Thanks for all the quick replies fellas! Sorry for my late response considering speed wobble is a dangerous situation even for a veteran rider(which I am not) So far that wobble has shown face again. As it sits now, I replaced the stock wheel bearings with allballs front and rear, Avon roadriders 90/90/18 front and 110/90/18 rear. Don't remember off hand what brand tubes but I used the proper sizes per wheel (after much research on google/kzrider) inflated to 40r 38f of air since the bike came off the table. Still using the chain and sprockets that and with the bike since the chain itself had 0 rust and wasn't binding up rolling over the smaller sprocket. Cleaned the chain up really good with a hard nylon brush in my parts washer bin till it dripped clear. Then I let it sit in a ziploc bag of PBblaster so it wouldn't rust till it came time to install which at that point wiped it down and blew out most of the blaster, heated it up a little with some map gas, blew some more, reheated as to simulate a quick ride sprayed it the shit out of it with maxima chain wax. Let it cool down on its own then installed. I've got it adjusted with 3" or less of up/down slack. However from what I noticed is that the chain rides more towards the hub in back and more towards the sprocket cover up front? BUT IT DOES NOT ride directly on the corresponding sprockets teeth faces if that makes sense? Like I can see an air gap, there's just more to one side both front and back...consistently. So that leaves me to believe that the rear wheel isn't riding directly center, but then again with how close it tracks now I'm sure it's OK per-say?
Now I'll admit that I do have the front tubes kinda radical in the triple. I'm gonna do that spring/spacer/custom lowering mod when I catch up on shop work in the next coming weeks. As for the rear, it's maybe 3/4" at most taller than stock. I made sure to get the same size (height wise I think 12 5/8? E/E) shocks, and I fab'ed up the new mounts and welded them in 1/2 more towards the front of the bike. I've been riding the bike a total of I think 7 weeks now and only thing that has changed is that I did lower the front tubes more to the position they're currently at about 5 weeks and some days ago? Before they were 1.5" sticking out no probs. now I have them at 2.25". If that was the cause, I'm sure I woulda felt the wobble a lot sooner?
I know I definitely need to get a front fork brace going! I could bolt up the stock 440 but it looks damn silly cause the wheel size now and Id hate to chop it up cause it's in pretty damn good condition! Not a single dent! The chrome needs some(well more than some)TLC, if flat chrome existed, that's what it resembles? Lol. I don't have an english wheel or any of the panel shaping tools aside from the body repair dollies and hammer which can be used "after" getting the initial shape. I don't mind using elbow grease, but thanks to tennis elbows, my grease dries a lot quicker now a days.
So anyways..that's where I'm at now with the wobble situation. I have tried to make it happen again on the same area of where it happened but no luck? The only thing that's missing is a box truck in front of me and some prestorm gusty wind.


ed

Chain slack should be less than an inch at it's tightest point.


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I think your tire pressure is too high. i would start at the recommended factory setting and change form there if you like. I think its like 28/30 but you should check to be sure. Take a straight edge and place it on your sprockets. they should be on the same plane. Dropping the forks through the trees can have a significant effect on handling, because by lowering the front end you are shortening the trail, making the bike more responsive but also less stable. Usually you can get away with an inch or so, if you lowered then 2.25" and went to a 18" you have lost at least 2.75" in the front, and gained an 1/8th inch in the rear(stock is 12.5"), compounding the issue. This could likely be the source of your problems... I would put them to stock and see if the problem persists. Also if it hasn't been beaten to death enough already.... fork brace needed.

heres is some reading on rake and trail if you are interested....

www.motorcycle-superstore.com/4125/mngr/...trail-explained.aspx

So the wobble still hasn't occurred since the first experience. Haven't made any adjustments except tire pressure and readjusted the chain sagg (thanks Vic and Nebr) but now a more pressing problem has risen as I was exiting the freeway to work this morn. Was a little wet and windy this morn, no biggie. It's about 12.7miles from my place to work. Near the exit the bike started feeling like I was running out of gas which wasn't the case cause I just filled up last night? So coming down the hill of my exit the motor starts making an audible "knock" thats consistent with the rpms. The knock is only happening in the higher rpms though. I'm freaking now cause I still had another mile before I get to my shop!? I did my best to keep the revs low for that mile. Bike still idles but it's a little lower than before. Oil is between the lines in the window. Did a valve adjustment weeks ago to spec. which improved engine/carb performance. Oil is Maxima premium4 10/40 and a K/N filter. Before the bike came of the table fresh oil and filter was added, put 1k miles on it or so and changed both again just 2 weeks ago. Gonna hook up an oil pressure gauge inline with the sensor and see what that shows. Any other thoughts would be fantastic as fuck! Lol..thanks guys!!


ed

Sounds like a rod bearing.


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Nebr_Rex wrote: Sounds like a rod bearing.
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That's what I'm assuming? Smh..I've heard rid knock plenty of times on cars an such, never heard it on a bike but it surely sounds the same I didn't have any type of oil pressure gauge for the sake of it so went on ahead and put new a filter. The old oil looked a bit on the darker grey side like carbon was getting in it, didn't see any glitter or shavings though. Anyways, new oil and the knock is 90% gone. The odd thing now is when I first started it, the knock was there like all the oil was gone but went away after the bike started. It's still audible ever so slightly but I'm still reluctant to ride it home? Where's a good source for rod bearings and a gasket set? Went to Z1's web but didn't see any choice for bearings?
Actually they have brown. Not sure what color I have yet so gonna wait to order thems.


ed

if the crank specs out, grab any for pickings are slim.


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So gonna start tearing down my motor to fix the rod knock. I feel pretty good that I caught it earlier enough and took precautionary measures while riding with it, that I didn't do any major damage. Before I can order any kind of bearings, I gotta get to the crank. if worse comes to worse, I can give Brian a call at Crower and see if he can source me something? I'm gonna try to get this done within a weeks time hopefully? I'll definitely look over everything else as I've been reading and studying the manual on kz400.com religiously!!
Here's a list of things I've got in hopes to make this as easy and painless as possible..

Ziploc bags of various sizes...CHECK.
Roll of masking tape for labeling said bags...CHECK
New sharpies to write on said tape to label said bags...CHECK
Rags...CHECK
Various micrometers? ...CHECK
Repair manual.(it's a digital PDF on my ipad)..so...CHECK
Brush to clean(motor ain't dirty though..jic )...CHECK
Music...CHECK
Peace and quiet so I won't get side tracked(have the shop all to myself right now)...CHECK
Cans of paint since it'll be torn down...CHECK
Gasket kit on order...CHECK
Tools...CHECK
Preparedness for the worst?...small check

If you think I might need anything else or got any last minute tips, feel free. as this mission is gonna be underway in roughly an hour PST



ed

happy hunting!

leon