Lighter Timing Advance Springs

Hello All,

Where can I buy lighter timing advance springs for the KZ 650?

Thanks Tweasl

I don't think you can buy lighter (or any for that matter) advance springs.

I am curious as to why you would want the advance to be at a lower rpm, stock KZ650 reaches full advance by ~2500 rpm anyway.

Post edited by: steell, at: 2006/08/28 18:39

if your willing to measure length, diameter and wire sizes chances are you can get some at mcmaster car. ive done this for japanese machinery so why not advance mechanismns? steve

Steve, I was just thinking that lighter springs would have no effect on the rpm full advance was achieve as the weights sling out via centrifugal force and the springs, being compression springs, actually just return them. Is my thinking faulty on this? Never occured to me before that someone would put different type springs on an advance. The lighter springs would serve to decrease advance more slowly than the original engineers intended and I see no purpose.

You can buy springs most anywhere but had best know what type springs you need. These are COMPRESSION ONLY springs. Most hardwares carry few compression only type springs. I think this is a questionable idea anyway but would like to hear the rationale for wanting different springs.

I can understand that a lighter spring would let it advance at a lower RPM and a heavier spring at a higher RPM. But, as everyone else has mentioned, why???
But then this is coming from a guy that likes to experiment with a little different ideas too, :laugh: :laugh: :laugh:

Bad idea in my opinion. I have a motor that had slightly worn springs (in other words, "lighter"). The full advance was about 400 RPM sooner than stock. Apparently, the previous owner could not tell when a motor knocks and he must have rode the piss out of it that way. But the knock was plain as day whenever you'd whack the throttle. The main bearings (or maybe wrist pin bearings?) are shot now, and make scary noises. But at least I got the bike cheap because of it.

Post edited by: loudhvx, at: 2006/08/29 12:54

not sure about the 650 but the 900 and 1000 are at full advance at about 2350rpm. So your allways in full advance when your riding anyway.so i dont know how this would affect eng. knock unless you road under 2350 rpm would it?The Dyna 2000 system alows you to adjust the advance electronicaly.But again I'm not sure Why you would change it from stock?

The 550 doesn't reach full advance until 3200. If you find yourself cruising at 35 in top gear (because of traffic or whatever), then try to accelerate without a down-shift, it would knock pretty noticeably.

Also, as a side note, my friend recently bought a gpz 550 where the first owner was a Kaw mechanic and installed heavier springs from some other bike. He installed them right when the bike was new to reduce knock. That motor is the quietest 550 I've heard, and I'm not talking about the exhaust (which is a Kerker), but the mechanical noises from the motor are very minimal. I'm sure it doesn't hurt that the guy probably changed the oil like clockwork and did valve shims by the book. That said, the bike is very sluggish compared to my previously-knocking-motor bike. We'll probably put some stock springs in to liven things up a bit.

Post edited by: loudhvx, at: 2006/08/29 14:25

WG, just in case it's not clear yet, think what would happen with no springs, the first revolution of the crank while starting would sling the weights to the full advance position. Changing weights and springs is a tuning trick from the days of point type distributors in automobiles, back when the coolest piece of tech equipment was a Sun distributor machine

as a matter of fact i remember thosesun machines! and by the way most advance springs are extension springs not compression guys. i was thinking it would make better sense to hold off advance not make it happen sooner in the rpm ranges but each to his own i guess....steve

Which type spring is ruined when you pull it apart? A compression or extension? I didn't know much about the subject till I went to a hardware that stocks lots of springs and was amazed to find three types. I had had a rusted/frozen advance and stretched the springs. As I recall, the springs would only return (compression?). In any case, I was able to find a "both way" spring that had compression and extension and they worked fine or at least I couldn't tell the difference. I guess what Steve Elliot is saying about no springs does make no sense...there would be no control on the rate the weights slung out. I wonder what happened to the guy who originally asked about this... prolly chased him off bwhahaha

I wonder what happened to the guy who originally asked about this

That's the question I was getting ready to post