some rekluse questions

[tech24]

well I might be able to squeeze the old lady for a rekluse for christmas so I've been searching for info. I'm gonna get either z-start pro or core exp (if she'll spend that much).

My main question is what is the main difference between the two, Is it only the clutch feel thats different or are there more I'm not finding?

are there any ill effects or disadvantages for either?

does the bike still stall at times? Because everyone talks about not being able to bump start which I never do unless I stall on top a hill or something.

Any more info you guys wanna throw in is good too....thanks!

Anyone have one on their 2010 or 2011?

[grayracer513]

The Core EXP is said to retain the stock clutch feel and modulation, while still providing the auto release as a stall preventative. My understanding of it is that it works something like the Trail or Revloc Dyna-Ring except that the entire rest of the clutch is beefed up to remain at racing grade strength and capacity.

http://rekluse.com/exp.shtml

The Z-Start Pro does provide manual override and modulation, but it feels quite a bit different than stock. At speeds high enough to engage the clutch, the pull is lighter than stock. At lower speeds, the lever feels slack and disconnected. Kind of weird, but cool too, in a way.

http://rekluse.com/zstartpro.shtml

The Z-Start Pro is very tunable by removing the outer plate with the bike on its side and changing among the provided springs and/or the number of balls in the pressure plate. Both the RPM at which it engages and how quickly it engages can be adjusted.

I recently installed one on my own bike and it is kind of cool. I've made deliberate attempts to brake stall it and not been able to. However, the way it's currently set up, I can still stall the bike by lugging it too low under a load (like being a gear high on a climb) and having the engine kick back on itself. Manual modulation prevents that, but I may try a little looser setup, too.

Give Rekluse a call and talk to them about the Core EXP, or maybe someone who has run one or both will chime in.

http://rekluse.com/contact.shtml

[tech24]

Thanks for the info. That was kind of my understanding. I thought I read somewhere you had one. Seems like you're happy with it!

I'm trying to justify the price difference although I would like the cover too.

Do you think a heavy flywheel would change anything for better or worse? Being the 2010 is stall friendly while lugging I was wondering.

[grayracer513]

The jury is still out on the clutch but I'm not unhappy with it.

Heavier flywheels do help, especially with an engine like the YZ that have so little rotating mass. In general, adding flywheel weight will, at some point, slow an engine's "snap" and tendency to build revs from low RPM, but my experience with the YZ450 is that this is not even noticeable with them. They're just so light to start with that it doesn't matter. You can, however, notice a subtle improvement in how smoothly the engine pulls at lower speeds, and it is less prone to stalling with the extra weight.

At least on the pre-2010 models, a heavier flywheel is a win-only modification, and a definite improvement overall.

[tech24]

I doubt I'd notice anything but an improvment on the 2010 also. Just so I'm clear you think Flywheel + rekluse is a good combo. If thats the case I might get the pro + heavy flywheel and have a nice solid setup for about the same price as the EXP.

[grayracer513]

The flywheel and the Rekluse work fine together, and while they both help reduce stalling, they do two entirely different things, both of which are beneficial. Using both is not redundant, nor is it overkill, and there's no performance penalty that anyone would notice.

[ForsheeMS]

Both are very good clutches. From my experience the Z-Start Pro is a better choice for woods riding and the Core EXP works better for MX riding. I've seen 3 of the Core cluthes go out in a 2 hour woods race although the conditions were extremely muddy.

IMO the Core EXP is easier to install and easier to adjust. It comes with different springs and other parts making it very tunable. To adjust the "installed gap" is simple and can easily be done in 15 minutes without having to take the clutch apart. As Gray said, the clutch lever feels nearly identical to stock. I just put one on a CRF250 and after the initial break in and readjustment I tried as hard as I could to stall the bike and couldn't.

The Z-Start Pro clutch is a little more time consuming to install and adjust. It is very tunable as well. Adjusting the "installed gap" takes longer and the clutch has to be disassembled to install thicker or thinner steel plates. There are more parts involved but it's still nothing too complicated. My woods rider has the Z-Start Pro in his '09 YZ450 and is also nearly impossible to stall when set up correctly.

Both clutches come with excellent instructions and I feel that most anyone that can replace a stock clutch could install the Rekluse. If you are an MX'er I would go for the Core EXP but for woods riding I feel the Z-Start Pro will work just as good but be more durable.

[tech24]

Both are very good clutches. From my experience the Z-Start Pro is a better choice for woods riding and the Core EXP works better for MX riding. I've seen 3 of the Core cluthes go out in a 2 hour woods race although the conditions were extremely muddy.

IMO the Core EXP is easier to install and easier to adjust. It comes with different springs and other parts making it very tunable. To adjust the "installed gap" is simple and can easily be done in 15 minutes without having to take the clutch apart. As Gray said, the clutch lever feels nearly identical to stock. I just put one on a CRF250 and after the initial break in and readjustment I tried as hard as I could to stall the bike and couldn't.

The Z-Start Pro clutch is a little more time consuming to install and adjust. It is very tunable as well. Adjusting the "installed gap" takes longer and the clutch has to be disassembled to install thicker or thinner steel plates. There are more parts involved but it's still nothing too complicated. My woods rider has the Z-Start Pro in his '09 YZ450 and is also nearly impossible to stall when set up correctly.

Both clutches come with excellent instructions and I feel that most anyone that can replace a stock clutch could install the Rekluse. If you are an MX'er I would go for the Core EXP but for woods riding I feel the Z-Start Pro will work just as good but be more durable.

Thanks for the info, I ride mostly trails and woods with some MX for fun. I'm kinda leaning towards the pro especially after reading this. RM has a good price on a pro too but its not in stock but of course they have the exp.

Now to see if the old lady will spring for the GYTR flywheel too ?

[Jim813]

There's two things I don't like about auto clutches in general (and you touched on one).

1. The bike can't be bump started.While this usually isn't a huge problem for a kick start model like the YZ, a KTM, Husaberg, BMW, or any other bike with electric start only would have no back up way to start the bike if any were to problem arise.

2. If the bike does happen to stall with an auto clutch, for example on a hill, the transmission will no longer keep one from rolling backwards down a hill. This can make things, in a word, interesting (especially for riders who don't know this)?

I agree there are some great advantages, but there are also disadvantages like listed above to consider.

[tech24]

I don't mind no bump starting but never thought about coment #2 and that would be interesting if unexpected for sure but I'd imagine if it occured too often one would get used to it.

[grayracer513]

This can make things, in a word, interesting (especially for riders who don't know this)?

Another thing that falls into that category is this: The fact that the engine will turn over without moving the bike DOES NOT mean that it's in neutral. In my case, my bike is so nearly impossible to start in gear that I discovered this because the bike wouldn't start, and I noticed the drag when I tried to roll it to a more favorable spot to kick it. Imagine, though, if it had started in gear with the lever released.

Also, beware, as you sit idling in gear, of one of your adoring fans walking up and tweaking the throttle for you. ?

[tech24]

That was another question I had how does it start in gear? I was hoping easier being thats a problem for me already but I guess you answered that one. And the only way I can start in gear is with partial throttle so that sounds like a dangerous mix too.

[grayracer513]

If it starts in gear for you as is, nothing should be different with the Rekluse. You just need to be sure to hold the clutch lever in, same as now.

[080]

That was another question I had how does it start in gear? I was hoping easier being thats a problem for me already but I guess you answered that one. And the only way I can start in gear is with partial throttle so that sounds like a dangerous mix too.

Starting in gear works fine. Most of the time it starts easier pulling in the overide which kinda asnwers your second question as well. I use to have a regular z-start in my honda and it would only start in nuetral but my yamaha with the pro version has had no problems starting in gear. In answer to the hills, you get use to being quick with the breaks if you jump off. I feel the pro's out weigh the cons.

[tech24]

If it starts in gear for you as is, nothing should be different with the Rekluse. You just need to be sure to hold the clutch lever in, same as now.

? had a brain fart forgot about the clutch lever for some reason

[tech24]

on another note what special tools do I need to install? Just regular clutch tools?

[grayracer513]

Yep. The only specialty tools needed are two wire gauges used to set the release gap, and they come with the clutch.

[ForsheeMS]

Yep. The only specialty tools needed are two wire gauges used to set the release gap, and they come with the clutch.

That's for the Z-Start Pro only. I've actually found that standard feeler gauges work better (at least for me).

My woods rider has to do dead engine starts so it's in second gear. The only time it doesn't start first kick is when he gets ahead of himself and twists the throttle before he has kicked it.

[grayracer513]

To be clear on that point, any bike that starts well in gear with a normal manual clutch is no less likely to do so with a Rekluse of any kind installed. YZ450's in general are not very good at in gear starts (though some do it just fine), and mine in particular has never done it well at all. It has nothing to do with the Rekluse one way or other.

[WB450]

I doubt I'd notice anything but an improvment on the 2010 also. Just so I'm clear you think Flywheel + rekluse is a good combo. If thats the case I might get the pro + heavy flywheel and have a nice solid setup for about the same price as the EXP.

Exactly what I have in my 07 and I love it. The power is smooth and usable at all times.