R6 clutch spring mods..

Discussion in 'Tech' started by noles19, Mar 16, 2018.

  1. Schwiz

    Schwiz Well-Known Member

    Now I'm going to take the cover off and take pictures for you guys. My end goal is to have more clutch slippage when downshifting, so what rob is saying, does make sense. I will then want to cut the springs further then.

    Thinking about it, I suppose there are no potential issues to cutting the arms of the springs all the way off. If I left part of the arm, and it was able to rotate around, then I'd be concerned.

    I don't have time tonight to work on the bike, but I'll get out there Thursday after work and take some pictures.
  2. rob linders

    rob linders Well-Known Member

    Based on your above stated goal, no need for pictures, cut the rest of the arms off on two of the springs.:timeforabeer:
  3. Gecko

    Gecko Well-Known Member

    Replaced the clutch yesterday, and went with the '10+ cut Y springs (arms cut off two of the springs). Also went with a taller stack, at the height Rick recommended. Looking forward to opening round this weekend.

    One friendly install note: When it came time to place the cover back on, I laid the bike down on its side, on top of a spare car/truck tire (no rim, just the tire). The cover went on easy-peezy, first try. I'd definitely recommend it.
    Last edited: Apr 23, 2018
  4. rob linders

    rob linders Well-Known Member


    I have a picture of me doing that in here on some thread and Broome puked looking at it. That's the fastest and quickest way for me.

    I saw a picture, probably on that other thread, where someone bent a piece of wire, inserted through the oil fill hole to line everything up. We already sold the R6, or I would have tried that, to see how well it worked.
    TurboBlew likes this.
  5. Gecko

    Gecko Well-Known Member

    I tried it with the piece of wire through the fill hole, you know, just to see how well it would work ... which is precisely why I posted the "friendly install note."

    Funny side note: When I first took the cover off, I thought to myself "how bad can it really be to put it back on?" So with it still in my hand, I tried to get the cover back on. Pulled the dowel out, it seemed to stay, line the cover up, pushed in, twisted the gear ... and clunk, it went right in! That's when I pretty much knew it wasn't ever going to ever go back in that easy for me. And I was right, until I laid the bike down on its side.
    rob linders likes this.
  6. Schwiz

    Schwiz Well-Known Member

    I just used a small extendable magnet to get the arm in the cover. Worked well.

    That's awesome you used gravity to your advantage though, haha!!
    rob linders likes this.
  7. Gecko

    Gecko Well-Known Member

    Yeah, probably the first and last time that gravity will ever work to my advantage on the bike.....
  8. MXjunky

    MXjunky I just wanna go FAST!

    Wow, the Y springs got beat to death in this thread. Lol all great information, thanks to all that contributed.
    Unlike what Melk-Man has advised, i did cut all the springs in addition to custom EB tuning through the ECU with Bauce. I did this because I wanted a closer feel to 2T bikes I grew up riding and coming off an SV I wanted more control of my cornerspeed. EB is no where near tunable on SV but I did learn to maximize cornerspeed.

    Couple things I noticed with cutting all the Y springs. I have almost ZERO mechanical EB. it's kinda insane if you jump from 1 cut spring to all cut, very similar to 2stroke riding, it's awesome, you better understand how to brake though, pads will get ate up much faster. With that being said I will be going back to 1 full spring to find a little more balance. The next thing, is my launches have kinda suffered. I have totally chaulked this up to rider error, which was hard. Riding the SV I have many holeshots on the field, it was a strong point for me and I have struggled with the R6. BUT I am thinking my clutch setup has a little to do with it. Possibly my stack height which I never paid attention to, I ran stock stack through a diagram that places the larger steels at the rear and let it eat. Rookie mistake, I will be measuring and adjusting according to Rick's recommendation.
    That brings me to the last thing which was barely mentioned at all, basket springs. Its my understanding that these should be changed according to HP, bigger motors require more spring. How else do these springs affect riding with a stock motor? I have YEC springs on hand, could I benefit from mixing these in with stock or just full on YEC.


    Sent from my SM-N950U using Tapatalk

    MELK-MAN The Dude abides...

    tommy, i don't know anyone that actually needs YEC pressure plate springs. OEM will work FINE even with mild SUPERBIKE builds. I've done it for years. zero issues. never an issue with my ss motors either, all tuned with MR12 fuel. This of course assumes you keep the stack height in spec, and replace the coil springs for the pressure plate periodically, there is a min spec in the manual for length but i just replace with every new clutch (they come with the yamaha clutch kit )

    if you understand how the back torque slipper works... the inner hub rides up rides up a ramp that lifts the pressure plate away from the clutch stack... it's pretty clear why you need at least part of ONE of the "Y" springs. Otherwise, your slipper is a light switch. The moment there is any back torque at all, the stack is released. not ideal, and why the kit manual states you need 1 'Y' spring at least (regular owners manual won't discuss modifying Y springs)
    TurboBlew and MXjunky like this.
  10. TurboBlew

    TurboBlew Registers Abusers

    Are you talking about the pressure plate springs? You can put heavier springs in it but I hadnt noticed it prolonging pack life.
    The only real benefit would be on a launch and a heavier feel at the lever. You can start by adding 3. Barnett offers some.
    or you can also shim the stock springs with washers.
    Also your launch RPMs need to be above 11,000 rpms. No ifs ands or buts. I saw where @DonTZ125 was offering stand alone launch control for around $125... seems like a deal considering. Just flip a switch on the grid for your preset launch RPMs... put the throttle on the stop at the 2 board and off you go without having to look at the tach.
    MXjunky likes this.
  11. MXjunky

    MXjunky I just wanna go FAST!

    I think we have spoke about these Y springs before Greg. Definitely makes sense, as before this was a setup previously used by Barnes when he won the 200. Obviously we would need to speak with him or his technician to find out what that clutch looked like afterwards, but in my case it was not detrimental. I did like the feel of the bike at entry, although it did take a little getting used to, and a slight change of riding style. Now with that being said, could this be the cause for my inconsistent clutch feel at launch? probably, because i did feel what i thought was the rear wheel spinning, it was actually the clutch not engaging properly. while racing this was not an issue for me.

    good deal, i am going to practice and try a few different things with the clutch, starting with stack heigh, and 1 y spring. I will say one of my best launches started around 4000rpm, advice i took from Jimmy Fotinopoulos, it worked but still not the blast off needed to take control of a sprint race.
  12. stangmx13

    stangmx13 Well-Known Member

    I’ve noticed two things that cause bad launches, grooves in the basket and too low stack height. The first is an obvious problem. The second, I think some tuners go rly low on stack height to get more slip. But it seems to reduce the friction zone and make it hard to modulate the clutch on launches. Of course there’s probably a lot more time to be made up on all the corners during a race compared to the single launch.
    MXjunky likes this.

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