yz450f 14/15 rekluse and ffw


14 replies to this topic
  • lukea918

Posted August 20, 2015 - 12:43 PM

#1

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



  • GHILL28

Posted August 21, 2015 - 08:32 AM

#2

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.



  • grayracer513

Posted August 21, 2015 - 10:14 AM

#3

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.



  • GHILL28

Posted August 21, 2015 - 01:18 PM

#4

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?



  • grayracer513

Posted August 22, 2015 - 11:02 AM

#5

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. 



  • Monk

Posted August 22, 2015 - 11:26 AM

#6

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...

  • GHILL28

Posted August 22, 2015 - 06:17 PM

#7

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



Visit the ThumperTalk Store for the lowest prices on motorcycle / ATV parts and accessories - Guaranteed
  • grayracer513

Posted August 23, 2015 - 07:25 AM

#8

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



  • Monk

Posted August 23, 2015 - 08:08 AM

#9

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


On the Core it is...

  • grayracer513

Posted August 23, 2015 - 08:01 PM

#10

Obviously.  The Core and Core EXP are complete clutches.



  • Monk

Posted August 24, 2015 - 06:20 AM

#11

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

  • GreenHornet450

Posted August 24, 2015 - 06:28 AM

#12

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, August 24, 2015 - 06:29 AM.


  • GHILL28

Posted August 24, 2015 - 08:46 AM

#13

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...



  • GreenHornet450

Posted August 24, 2015 - 10:36 AM

#14

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

  • GHILL28

Posted August 24, 2015 - 12:16 PM

#15

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







Related Content

Forums
Photo

YZ450F 03 Sparks driving me crazy by SirAttard


Dirt Bike   Make / Model Specific   Yamaha   YZ 400/426/450
  • 5 replies
Forums
Photo

Is it worth it? (Cam and High compression piston) by macgi77


Dirt Bike   Make / Model Specific   Honda   CRF 150/230 F/L
  • Hot  36 replies
Forums
Photo

Megabomb Fitment by 288yz450


Dirt Bike   Make / Model Specific   Yamaha   YZ 400/426/450
  • 1 reply
Forums
Photo

Snake pit oct 30th by The Anvil


Dirt Bike   Dirt Bike Regional Discussion   California
  • Hot  293 replies
Forums
Photo

First Hare scramble tips by dhend8


Dirt Bike   General Dirt Bike Forums   General Dirt Bike Discussion
  • Hot  33 replies
 
x

Join Our Community!

Even if you don't want to post, registered members get access to tools that make finding & following the good stuff easier.

If you enjoyed reading about "" here in the ThumperTalk archive, you'll LOVE our community. Come join ThumperTalk today!

The views and opinions expressed on this page are strictly those of the author, and have not been reviewed or approved by ThumperTalk.