yz450f 14/15 rekluse and ffw

Hey Guys,

 

just wondering if adding a recluse exp 3.0 and a 9oz stealthy flywheel weight would be too much fly wheel weight? I do mostly single trail with some fire trail and the odd motocross day.

 

cheers

Luke

The Rekluse adds some effective FWW.  I do a good mix of things with just the Core EXP and the MXA map in my '14 and it's fine.

I am a big time advocate of adding rotating mass to YZ450's in general, but adding 9 ounces to the already much larger flywheel (compared to pre-EFI models) on the '10-'16's might maybe be more than you'd like.  4 to 6 or 7 sounds about right.  On the other hand, using an auto clutch can't replace all the advantages of increased RM, so I still advise adding weight.

 

As to clutch component weight, in the first place, the Rekluse products are not particularly heavy as compared to stock components.  Even if they were, there are three things to consider before regarding them as a source of increased rotating mass:

 

  1. The engine has a 2.65:1 advantage over the entire clutch assembly, so it can accelerate almost 3 times as much clutch weight with the same torque that it would take if it were direct-mounted to the crank.
  2. The clutch assembly spins at 2.65 time slower speed, and so develops that much less inertia mass.
  3. The clutch assembly, when attempting to transfer inertia energy back to the crank, has to do so at a 2.65:1 disadvantage.

 

In other words, yes, there is some effect, but it's entirely insignificant.

Now I'm curious what the total weight of the components removed from the clutch are versus the Core EXP kit that replaces them.  I can't get a feel for that off the top of my head right now.  Only installed a couple of these.

 

With the Z-Start Pro, there's a substantial amount of weight added.  Not enough to equal a flywheel weight, but enough for SOME effect.  I forget what it's equivalent to.  I recall hearing 6oz or so?

With the EXP 3.0, you're trading the expander assembly for what, 3 plates? Not going to be a big percentage weight change in the perspective of the weight of the entire clutch. 

 

With the Z-Start, there is more, most of it in the form of the steel balls that drive the pressure plate, and in trading the aluminum pressure plate for steel.  The boss is heavier, but it's smaller in diameter than the rest of the assembly.  Six ounces seems like quite a bit, and a good deal of it is located well outboard on the radius of the clutch, but you're still fighting the primary reduction ratio, as noted. 

With the EXP 3.0, you're trading the expander assembly for what, 3 plates? Not going to be a big percentage weight change in the perspective of the weight of the entire clutch.

With the Z-Start, there is more, most of it in the form of the steel balls that drive the pressure plate, and in trading the aluminum pressure plate for steel. The boss is heavier, but it's smaller in diameter than the rest of the assembly. Six ounces seems like quite a bit, and a good deal of it is located well outboard on the radius of the clutch, but you're still fighting the primary reduction ratio, as noted.

Rekluse components are billet vs the lighter stock cast units...

The inner hub is changed on both of them too, and I don't think the Rekluse unit is the same weight or lighter.

The boss (inner hub) is not changed on an EXP 3.0.

The boss (inner hub) is not changed on an EXP 3.0.

On the Core it is...

Obviously.  The Core and Core EXP are complete clutches.

Funny, I might have to eat my words regards of weight. I weighed the pressure plate alone and it was over 100g lighter...

20150823_195842_zps9jtrv6qz.jpg

20150823_195830_zpsz64au2yw.jpg

I have the EXP 3.0 CORE.... The Inner Hub and Pressure Plate are LIGHTER than OEM. Also the Pressure Plate is opened up more for increased oil flow. I do notice less fww effect

Edited by GreenHornet450

Oh nice...now I'm kind of curious what amount of FWW would effectively bring it back to stock.

 

I'm pretty sure the Z-Start Pro components end up being quite a bit heavier.  Maybe not though since there are 6 bolts and springs that are removed...

The two mentioned clutch systems work entirely different and feel entirely different. With the 3.0 core you will get more free wheeling and less fww then the ZStart. I have both

Yep, same here.  ZSP in my 2T, Core EXP 3.0 in my 4T.  I just don't have to touch them that frequently...

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