Rekluse Z-Start Pro On 03 YZ 450

I just put a Rekluse Z-start Pro on a YZ450. It works ok but the engagement is a little off. I takes off right away with a little rev but when I slow down to stop it wants to stay engaged and keep driving. This sometimes stalls the bike which is the whole reason I got the clutch to eliminate stalling. I already like it for riding around slow. Is this just a matter of using the adjuster to get more tension or do I need a stiffer spring? Should I wait till after the recommended break to set the engagement or play with it now?

Edited by JLB943

I just put a Rekluse Z-start Pro on a YZ450. It works ok but the engagement is a little off. I takes off right away with a little rev but when I slow down to stop it wants to stay engaged and keep driving. This sometimes stalls the bike which is the whole reason I got the clutch to eliminate stalling. I already like it for riding around slow. Is this just a matter of using the adjuster to get more tension or do I need a stiffer spring? Should I wait till after the recommended break to set the engagement or play with it now?

If it takes off fine but wants to stall when stopping, it may be that you are not letting off the throttle. Your statement about adjusting the cable to get more tension is NOT what you want to do. You need to rev it up and then adjust the play just as the directions state and let it be. Adjusting tension will burn up the clutch fast. If it idles and takes off fine then the springs are fine.

The ZSP clutch can be adjusted for two different attributes to give 6 different settings. The engagement point, which is the RPM at which the clutch engages, can be set at low, medium, and high RPM, and the engagement rate, which is how abruptly the clutch engages once it begins to, can be set to fast or slow.

The engagement point is set up by choosing between three different spring setups. More spring raises the engagement RPM.

The engagement rate is set by choosing between using 27 balls in the pressure plate or 24. 24 will engage the clutch less abruptly than 27.

The manual that comes with the clutch recommends starting with the medium engagement point/quick engagement rate, but I found this to be unusable in my '06. The engagement was too quick to allow second gear starts, for instance, and the engine would stall under some other conditions, including braking on occasion. To correct this, I set it up using the medium/slow setup (both short springs, and 24 balls), and it works fine now.

How do you have yours set up currently?

Currently, mine has 30 balls in it as given by the instruction. I am using the medium spring with the standard adjuster. I may try turning my idle down a tad to get it to stop. It seems like it is very close to being adjusted correctly. I went a little tighter on the adjustment and it started stalling on start so I will back off a bit. My fear is burning the clutch up because when I put the brakes on to stop it keeps driving and in turn slips the clutch. I will be certain I am letting off the gas completely by taking my hand off completely.

Currently, mine has 30 balls in it as given by the instruction. I am using the medium spring with the standard adjuster. I may try turning my idle down a tad to get it to stop. It seems like it is very close to being adjusted correctly. I went a little tighter on the adjustment and it started stalling on start so I will back off a bit. My fear is burning the clutch up because when I put the brakes on to stop it keeps driving and in turn slips the clutch. I will be certain I am letting off the gas completely by taking my hand off completely.

I'm still confused on your statement about tighter on the adjustment? The lever adjustment has no bearing on engagement unless you have it without any gap at 5k rpm and if you are doing that you will fry the clutch very fast. Like I said before set the clutch lever with proper gap and forget about it. One thing that I have seen on a couple of ocassions is that the actual installed gap is to tight. Get two sets of feeler gauges and. check the actual gap with both feeler gauge 180* from each other. The smallest that it can be without issues is about 25 to 27 thousandth. Any thing below that and it will do as you describe. Good luck!

Another is jetting and oil. I run a 48 pilot, needle in stock position and a 162 main. I run 27 balls and the medium/hard set up and it works flawlessly. I also run Refline 10-40 oil. If the gap is ok then I suggest my set up. We have a bike with well over 300 hrs and it still has the original clutch.

If the clutch takes 30 balls at all, it's different than mine. Also, with the setup mine came with, the "medium" spring is actually two springs; an inner spring together with the shorter of two outer springs.

The first thing I would try, after verifying that you are in fact using the correct "medium" engagement point setting is to remove 3 balls from the clutch pressure plate. This will slow the rate of engagement slightly.

Be sure of your installed gap setting, also. Gunner is right about the cable. The cable has no bearing on the clutch operation unless it's set too tight. With the RPM elevated well above idle (3-4K), there must be 10-12mm of slack at the lever. If this is not there, the effect is exactly the same as with the standard clutch; it prevents the complete engagement and will cause the clutch to slip under a load, which will lead to early failure.

Jetting is an important consideration, true, but you have to avoid using a big fat pilot jet. Idle mixture that is on the rich side will cause an excessively rapid RPM drop when you let off at low RPM under a moderate or heavy load, while a slightly lean idle will cause the idle to "float", or "hang' very slightly, and avoid a lot of frustration. If the bike pops a little bit on decel 75% of the time, it should be about right.

The thing to remember about the Rekluse is that the same things that make it engage any certain way will affect the disengagement in the opposite way. That is, what makes it engage early will make it release late. What makes it engage quickly will make it release suddenly. The differences between each "step" are not very big, so it's not as if you go to the reduced ball count you will suddenly find the clutch slipping for 30 seconds on each launch. Just be sure you follow the instructions carefully and understand how the setup works.

You can always call Rekluse directly to get support from them, too. They're extremely helpful that way.

I believe this is an older style that has spaces for 30 balls. I bought it used off of someone. There is an adjuster that goes down where the stock clutch cable used to acuate on the case. I figured out by experiment that if I push this in with my finger the bike will stop wanting to drive when I go to stop so I figured by adding tension this would solve the problem. This is what I am adjusting. The clutch lever is no longer in use I am going to take it off. I had tWo sets of feeler gauges when I set it an the gap was around 40 thousanths. Looking at the literature they must have made some revisions to the Z-start Pro model design since this one was made. I am going to call them and see what their thoughts. I may remove the 3 balls to see how that affects the engagement.

Edited by JLB943

The model I have is the standard Z-start which makes sense why it is alien to you guys. They recommended playing with adjuster and spring rate to get it to work and then going in and bring the gap up to around .032 to .034 by switching another plate. I can't remember what the stock plates were but I thought .024 and Rekluse were .042 so mathemically this doesn't workout right but I have to double check. Thanks for the help I will play around with it and see if I can get it right.

The model I have is the standard Z-start which makes sense why it is alien to you guys.

I was thinking that was probably it. With the Z-Start, the clutch cable is an option, and requires a goofy adjuster at the engine. Rekluse support is your best bet there.

The model I have is the standard Z-start which makes sense why it is alien to you guys. They recommended playing with adjuster and spring rate to get it to work and then going in and bring the gap up to around .032 to .034 by switching another plate. I can't remember what the stock plates were but I thought .024 and Rekluse were .042 so mathemically this doesn't workout right but I have to double check. Thanks for the help I will play around with it and see if I can get it right.

Just so it's clear, the original zstart is not alien to me. I have a great deal of experience with those. Been playing with Rekluse clutches since 04. It sounds like you have the adjuster barrel on the clutch perch. Those were tricky because the barrel has the engagement spring and you have the slack adjuster also. I would tighten the adjuster barrel until it doesn't stall and be done. Just make sure you have the proper slack in the cable when rpms are raised. If you want my opinion, I would eliminate the two finger override and clutch lever. The override works very poorly and that may be why they no longer make the zstart and use the overide.

Edited by Gunner354

...I would eliminate the two finger override and clutch lever. The override works very poorly and that may be why they no longer make the zstart and use the overide.

The override on the original Z-Start was indeed the reason that model was phased out and replaced by the Z-Start Pro. The original override can be nearly impossible to operate at high RPM, whereas the manual lever on the ZSP displays only a little extra resistance when the engine speeds up. The Z adjuster was fussy and needed constant attention, whereas with the Pro, you pretty much just set it like a normal cable (with the revs up) and forget about it for a while. The Pro is a far better clutch than the old Z was.

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!


Register a new account

Sign in

Already have an account? Sign in here.


Sign In Now