TOPIC:

Hey, guys, what is the best all around performance transmissions for the Z1s? Six speeds? Were do you get them, how hard are they to swap etc? I would like to see if anyone has made a track bike style tranny in one of these?

I am "armchair" building my personal bike with my buddy Travis, and I got to thinking "what about the tranny"-

I want to make a Z1 track and street bike, or perhaps a custom framed super bike LOL- in least, in my own mind LOL- and the edumacation wouldn't hurt to know these things, best case scenario and money and talent no object type dream build up.

All the same suspension upgrades you would have with a modern race trackbike, but with Z motor basically- 1428cc trackbike motor, so what about the tranny? Slipper clutch available for these trannies? If so, where do you get them?

Post edited by: CruisingRam, at: 2006/04/11 00:30

I doubt very much there is a slipper clutch for a KZ. The best you could come up with is a close ratio tranny from old superbike racer.

you can get a slipper clutch for about $800.00

I think a slipper clutch for what is essentially a drag bike engine is a poor decision. A slipper clutch helps road racers a bunch as they are banging downshifts and don't want to break the rear end loose. You are looking for reliability and positive shifting with a drag bike engine. Take the gears to your local machine shop and have them undercut and check with the big boys in drag racing for quality shift forks and stronger 2nd gear... APE, SCHINTZ... those types will have a line on appropriate tranny stuff.

Well, from what I have been studying, and talking to a pro-drag racer and pro-track rider, there doesn't seem to be much difference between a drag motor and a track motor. Mostly has to do with oil supply and cooling from what I have seen- otherwise- what do you say is the main difference between the two types motor-wise?

Also, believe it or not- 800 bucks for the clutch seems like a bargain at that price- I have seen how much these sport bike guys drop in thier bikes, though they will never get the money back- I have seen 4K rims on a 3K bike!



Post edited by: CruisingRam, at: 2006/04/11 21:58

Post edited by: CruisingRam, at: 2006/04/11 22:00

wiredgeorge wrote:

I think a slipper clutch for what is essentially a drag bike engine is a poor decision. A slipper clutch helps road racers a bunch as they are banging downshifts and don't want to break the rear end loose. You are looking for reliability and positive shifting with a drag bike engine. Take the gears to your local machine shop and have them undercut and check with the big boys in drag racing for quality shift forks and stronger 2nd gear... APE, SCHINTZ... those types will have a line on appropriate tranny stuff.

WG, what you are talking about is more properly called a back torque limiting clutch, while the term slipper clutch generally refers to a clutch that initialy slips and then locks up as the rpms increase, beneficial in drag racing because it allows a peaky engine to be kept in it's powerband without sending the rear tire up in smoke.
Personally, I think the "Back Torque Limiting" clutch should be called a "Torque Override" clutch, and the "Slipper" clutch should be called a "Lockup" clutch.

Stupid marketing people screw up terminology all the time

I thought we had this discussion before, confusion still reigns
Earlier Discussion

Post edited by: steell, at: 2006/04/12 01:00

Well, my little mental exercise we were "armchair building" here was a trackbike first, street bike next, and will pop off easy 10 at the track- in other words, like a modern litre bike.

I have been on a track bike with a slipper clutch- I am familiar with what it does- it basiclly keeps you from lowsiding while shifting down LOL

But, backcut gears is not a bad thing either!

Post edited by: CruisingRam, at: 2006/04/12 15:03

CR, I had always heard of and referred to the type of clutch that doesn't lock up on hard downshifts as a slipper clutch. Steell disagreed with this definition. The MAIN difference in engine types (drag / track) is that track and street can generally be ridden all day long due to their ability to shed heat in varying speed and temp conditions where a drag engine will be more prone to overheating due to its thinner cylinder liners and very high compression. If I were drag racing, a clutch that slipped a tad off the line would help keep the rear wheel from going up in smoke or massive wheelies to that type clutch would be OK IF you were thinking of making the bike a drag racer. If I were road racing, I would want a clutch that limited lock up to prevent the back end from popping loose in a hard downshift. I have had this happen and it is sort of disconcerting to be riding along sideways when you didn't intend it. The back cut gears are one of my least favorite mods but are mostly necessary to keep hard ridden bikes from having the tranny pop out of gear. The reason I don't like this mod is that you have to be real precise shifting. The round profile on the stock stuff is there for a reason... it allows sloppy shifts to work hehe

I thought heat would be the main issue- of course, which is not an issue up here LOL- have had plenty of 1428cc bikes according to sources here, without so much as an oil cooler running hard just fine way up here in the greatland!

Your definition of a "slipper clutch" and mine are the same- but, to be fair, other sites do call the slider and slipper the same thing

perhaps we should call the slider a "modified centrifucal clutch?" LOL

Post edited by: CruisingRam, at: 2006/04/12 15:04

wiredgeorge wrote:

CR, I had always heard of and referred to the type of clutch that doesn't lock up on hard downshifts as a slipper clutch. Steell disagreed with this definition.

Both APE and the NHRA call it a slipper/slider clutch (the one that locks up as rpm increases), while other places refer to the back torque limiting clutch as a slipper, so what's a dummy like me to do?

It just seemed like CR was talking about a drag type clutch, and you were talking about the road racing type, and I was totally confused (sometimes I think that's my normal condition). If this keeps up I'm going to start prattling about gudgeon pins (and really get people confused, so I'll have company).

Post edited by: steell, at: 2006/04/12 16:37

steell wrote:

wiredgeorge wrote:

Personally, I think the "Back Torque Limiting" clutch should be called a "Torque Override" clutch, and the "Slipper" clutch should be called a "Lockup" clutch.

Stupid marketing people screw up terminology all the time

I thought we had this discussion before, confusion still reigns
Earlier Discussion <br><br>Post edited by: steell, at: 2006/04/12 01:00

Problem with that, is drag racing has both a slipper / slider and a lockup which are two different things.

The slipper / slider has no clutch lever. It is a real centrifugal clutch. Open the throttle and as RPM comes up, clutch begins to engage and move the bike. Just like a go Kart or mini bike.

A lock up, has the weight device on the inner hub and the weights apply pressure to the pressure plate as wheel speed increases. Basically it is just a helper devise that aids the clutch springs in slamming the clutch home in the higher gears where slip is more likely to happen.

Jay

All right, that does it, I have had enough of confusing clutchs! Now all I have to do is figure out how to put an automatic transmission on a 750 twin!!