Rekluse Clutches - Technical Thread - All Applications

Discussion in 'Thumpers' started by motobene, Apr 11, 2020.

  1. motobene

    motobene Motoing for 49 years Supporter

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    This thread examines carefully the Rekluse Radius auto clutch in various applications and will be skewed to be more technical in nature.

    I'm now 35 years in trials and thus have been an automatic skeptic regarding auto clutches. I'm back to riding more of the bigger bikes off road and having experienced some injury-stall crashes in scary places, and getting older. I'm now more open to the idea of auto clutches and wish to explore them.

    PLAN
    - Fit Rekluse Radius X RMS-6357 to my 2003 KLR ($679)

    If that works out reliably problems and/or auto clutch quirks don't drive me nuts:

    - Fit Rekluse Radius CX kit RMS-7902025 to my 2019 Beta 390 RR-S ($1,079)

    WHAT WON'T CHANGE?
    - Engaging and disengaging clutch
    - Manual clutch control via the stock lever

    WHAT WILL BE DIFFERENT?
    - Controlling clutch slip/engagement/disengagement with the throttle (rpm)
    - Manual clutch control feel changed somewhat by working in series with the EXP centrifugal pack
    - Setting the manual clutch 'free play gain'

    ...and about the same info without the friggin irritating bad boy music:

    - Bump starting requires an adjustment (no or lots of lever free play to get clutch lockup at idle rpm?)
    Bump Start Rekluse.JPG
    - In 4-stroke engines sharing the engine and wet clutch oil, JASO MA-rated oil is required. That is, oil having the friction modifying additives appropriate for wet clutches.

    WHAT QUIRKS MIGHT BE ENCOUNTERED?
    - Loss of downhill engine braking if the rpm drops to idle
    - Loss of the in-gear 'parking brake' (sloped-surface parking issue). Rekluse provides Velcro straps to hold the front brake.
    #1
  2. motobene

    motobene Motoing for 49 years Supporter

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    KLR650 Application RMS-6347 (version or rev. level C)
    IMG_20200409_155608.jpg

    The above was just received. Close inspection with measurement revealed very high design and consistent product quality.

    The documentation in instructions and warnings (adequate non failure to warn) show Rekluse to be a mature company with a lot of experience and well versed in 'negative knowledge' (faces takes place).
    IMG_20200409_155559.jpg
    #2
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  3. brewer90

    brewer90 Been here awhile

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    I ordered a CX for my 390 yesterday so looking forward to see how you approach this.
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  4. motobene

    motobene Motoing for 49 years Supporter

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    OIL SPECIFICATION & RELIABILITY (Including the loose nut behind the handlebars)
    As part of my investigation and a posting elsewhere I was informed of some Radius X clutches burning up in the KLR application.
    I wanted to know why, so I asked questions about riding style (use of throttle) and found that if a lot of slipping was
    going to be the case - and that might mean a less aggressive style with lower rpm - it can be insurance to pay close
    attention to what engine oil you use. I have yet to experiment with oils, but I'll start with the oil type recommended by Rekluse.

    From their web site:
    Oil for Rekluse Clutch.JPG
    Use JASO-MA oil. Do not use JASO-MB.

    JASO MA Oils.JPG

    In 2-stroke applications the oil can be very specific to the gearbox and clutch and that's good. Very good. Four stroke engines
    having separate geabox and clutch compartments also let you optimize the oil for the clutch. But in applications like the KLR,
    you have only one oil for both and certain compromises must be made.

    More on JASO specified oils:
    https://www.rymax-lubricants.com/blog/what-does-the-jaso-oil-specification-mean/

    https://www.oilspecifications.org/articles/JASO_MA_JASO_MB.php

    What is the difference between MA and MA2? MA2 is a new spec configured to not degrade catalytic converters.
    Usually that means certain additives that can react with the platinum catalyst have been removed and substitutes used.
    The KLR is non catalyst, so the MA oil could be better? It is also possible that MA2 simply supersedes MA.

    Note that this Shell Rotella T6 synthetic oil is MA rated:
    https://rotella.shell.com/en_us/products/full-synthetic-and-blend-oil/t6-full-synthetic.html

    So is Shell Rotella T4 mineral oil:
    https://www.bobistheoilguy.com/forums/ubbthreads.php/topics/4619477/rotella-t4-is-jaso-ma-ma2

    Some street knowledge I ran into was to avoid synthetics in Rekluse applications (yet Rotella T6 is MA rated). The idea is that synthetics may be too slick and allow too much clutch slip and thus more kinetic energy converted to heat. The following technical paper, however, does not favor this idea by showing how the oil base (synthetic versus mineral, which means 'from the ground) is NOT a big factor in wet clutches regarding torque capacity/slip. The paper says other factors are, like the additive packages.

    The paper is very technical, but there's some practical info to glean from it, if you have an attention span :-)

    https://www.diva-portal.org/smash/get/diva2:999829/FULLTEXT01.pdf

    The paper challenged some of my assumptions based on lots of clutch modification experience.

    I'll update this section as I learn more.
    #4
  5. motobene

    motobene Motoing for 49 years Supporter

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    You will lead me on this as I will concentrate on the KLR first. Please let us know what you find!

    At least with the Beta we have a separate oil compartment for the clutch, so we can use great gear oils with additive packages specific to wet clutches like Maxima MTL-80 and -85, Silkolene Medium, etc.
    #5
  6. ZachM1

    ZachM1 I'm a meat popsicle

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    And don't forget that Recluse has their own synthetic oil.
    I don't think their clutches like the one for the KLR were made to be used in a different manner than the stock clutch as far as gear selection. Common sense should tell us that much from a mechanical standpoint. As far as Dino vs Synth - no 2 oils are equal. I have had good luck with Amsoil "Dirt Bike" synthetic, but clutch slippage after extreme heat cycles with Mobile 1 Racing 4t. It took 2 flushes with Rotella T4 to get the stock clutches back to completely normal. About to try another regular parts store synthetic motorcycle oil (Shell Advance Ultra 4t Synthetic) on a stock clutch KLR before trying it on the Recluse KLR. I always try new oil experiments on the stock clutch before the Recluse.

    JPEG_20200411_154956_2078814934644965854.jpg
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  7. AZ TOM

    AZ TOM Long timer Supporter

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    DSCN2247.JPG
    In 2006 I bought this Husky. Very tall & every ride would stall & tip over. Installed the Rekluse ZstartPro. End of problems, best money ever spent. Once adjusted never touched & working fine when I stupidly sold bike at over 14,000 miles. Removed the clutch lever as it engaged better that I ever could manually. Also had one on my 2007 TE250 worked flawlessly also stupidly sold. They recommended Rotella T back then & never used anything else. Bought a DRZ400E a few years back & ordered there new auto clutch which similar to yours is just a clutch pack. Never installed it as I felt would not work or hold up as well for my kind of riding, so very skeptical of the one for the KLR!!
    #7
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  8. motobene

    motobene Motoing for 49 years Supporter

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    Zach M1 you are right about no two oils being the same. Most of the time people get hung up on synthetic or not synthetic and miss the critical importance of the additive package. Being a trials rider very interested in the engineering, I've done a lot of clutch slipping and experimenting and felt the difference between oils. I've heard several reports of clutch troubles with a specific oil. Mobile 1 Racing 4T noted.

    Rekluse synthetics in 10W40 and 20W50:
    Rekluse Oil.JPG
    Here's the Safety Data Sheet:
    https://m8j2s6z4.stackpathcdn.com/w...l-Syn-10W-40-and-20W-50-SDS-Sheets.pdf?x52855

    Rekluse Oil Ingredients.JPG

    They are pretty vague on the percentages and ingredients of the additive package and the zinc (anti-wear).

    I don't quite understand your first two sentences.

    Good tip on trying a new oil with a familiar clutch. You get to know the oil better before doing a total swap-out of the plates.
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  9. motobene

    motobene Motoing for 49 years Supporter

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    Nice looking Husky AZ TOM!

    The Z-Start Pro in your Husky is the older design that uses balls. Lots going on in that older design! Very configurable.
    Rekluse Z-Start Pro.JPG

    The newer design with the EXP base is way simpler! I have wondered if I was giving anything up on the engagement/disengagement, slip-zone characteristics with the newer design. The Radius CX has just a few more parts than the Radius X, but gosh, the Radius X has more plates than stock even with the EXP base taking up space.

    It's yes 'just' a clutch pack but the clutch basket and hub and pressure plate on a KLR, while not hard coated aluminum, are pretty robust machined cast aluminum and should be as reliable as before. Rekluse provides steel inserts so the driving steel-backed fiber plates do not ride on the aluminum tangs but rather slide steel on steel. Should all be pretty reliable, but we shall see.

    Your comment about not having a clutch lever is interesting. If I don't need a clutch lever on the big pig I could dedicate the space to a master cylinder and run the rear brake from the former position of the clutch lever. That could be quite advantageous to me! We'll see how much I can ignore the clutch lever. I suspect a lot, or perhaps entirely, as the torqy KLR has plenty of power. There are times, however when revving up and dumping the clutch could be handy.

    The virus has me presently separated from the KLR by 500 miles, but I should be able to install the kit within a week or two.
    #9
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  10. ZachM1

    ZachM1 I'm a meat popsicle

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    Unclear sentences explanation? - Abuse wise with some of the failures. Using the Rekluse to run in a gear lower than normal where you would normally lug but now slip the Rekluse will overheat the clutch in short term especially considering the weight of the bike we're motivating through this clutch. There's extra mechanical parts for engagement that also will not like the overheating on slippage/engagement abuse. Much less the overheating of the plates and frictions which on mine there are more of each than stock - so they're all thinner & more prone to heat warpage than stock in my opinion. There's not much room for tolerance changes (from extreme high temp) outside of the intended use parameters in the design. I can make my stock clutch slip and feel loose in the lever if I overheat it, but it will come back after it gets back to a normal temp.

    Of course this opinion comes from my past life as an automotive transmission specialist - specializing in severe duty and racing applications and also riding & working on motorcycles for even longer.

    That is a little deeper into the meaning behind the 2 sentences that weren't very clear.

    On the stock clutch testing vs Rekluse - I was lucky enough to get a good deal on an 08 with a freshly installed Rekluse to play with. My 2018 daily driver/woods bike still remains the stock clutch oil tester for now. Once I decide the pros & cons on "my" use of the Rekluse I might swap it over to my daily driver. Still undecided if the pros outweigh the cons. I like as much control over every aspect of the bike as possible. The Rekluse does take a little bit of that away. It does lend well to a few hard dirt riding uses though.
    #10
  11. motobene

    motobene Motoing for 49 years Supporter

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    Thanks. Running a lower gear (at higher rpm) leading to more clutch slip has me a bit confused as the centrifugal element has the clutch locking up by rpm. I was worrying more about lugging and heat buildup. Good observation on the heavier weight of the KLR translating into more potential heat.

    Rekluse clutch behavior will become clearer to me on the butt dyno:rayof

    Here's some clutch slipping:
    #11
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  12. Ten Speed

    Ten Speed Adventurer Supporter

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    I've had a Rekluse on my 07 Klr for 3 years. I like it, it works pretty flawlessly for me. Rotella oil. I like the fact of not stalling. Couple of cons for some people, bike will roll backwards on a steep hill if you can't get on brake pedal. No bump starting. I don't ride on really steep hills. I carry a micro start with me too. Pricey, but it works well for me. I'm gonna sell my bike and buy a Tenere 700 this year, if they come in.
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  13. ZachM1

    ZachM1 I'm a meat popsicle

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    Maybe I misstated that somehow. Lower rpm slipping does cause extra heat. Not higher rpm in a lower gear. I tend to overheat the stock clutch during the summer, riding the clutch doing slow technical deep sand, less than single track etc. while running a 16t - 42t combo. So that would be slightly higher rpm clutch slipping abuse.
    On the Rekluse KLR with 16t - 43t I still manually use the clutch in the same slow technical situation because better control vs low rpm = less control. If I were to not drop a gear and just use the throttle with Rekluse slip - I don't think it was designed for that. You still need to shift where it would be appropriate without the Rekluse. So yes, low rpm clutch slip abuse will fry a Rekluse on a KLR.
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  14. scruffy

    scruffy Been here awhile

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    I always ran Shell T6 in my 4 stroke KTMs with the old Z-Pro's and Core models . Never had a problem.
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  15. renogeorge

    renogeorge Let's ride!!

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    I’ve run Rekluse’s in my KTM and Husky 2 strokes and 4 strokes from 300 to 990 and RevLoks before that. I have not found them to be sensitive to oil selection. I have typically run Amsoil full syn in the 4 strokes and ATF in the 2 strokes. Also Rotella full syn. No problems with any of these or my customers with Japanese and Euro bikes. Adjustment/setup is what is critical. That and understanding that an auto clutch is not an auto transmission. Failures typically come from consistent riding in too high a gear with too low of RPM, because bike doesn’t buck and jerk telling rider to shift when needed. Adjust with minimum gap when fully warmed up and idling correctly. You want just the slightest pulsing with bike in gear and lever out. FWIW
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  16. motobene

    motobene Motoing for 49 years Supporter

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    'Slight pulsing' and 'minimum gap' I interpret as the clutch centrifugal component (via the older balls or newer weights) to be causing the plates to bump solid with each firing pulse when warmed up. So the adjustment is right there ready to hook the clutch up as soon as the RPM rises for less rpm bandwidth to get the bike going.

    I also like the comment about using the manual clutch for slow work sometimes.

    I appreciate all the experience coming out here! I had started my Rekluse postings in the KLR Only thread, but I was somewhat talking to myself, and that's a sign of inappropriate level of detail on one subject in a more general thread.

    One fellow said he had burned up two Radius X packs in his KLR and being on his 3rd pack with better luck. I asked him about his riding style. He ended up with stiffer clutch springs and changing the oil base and additives. In his words:

    "Motobene, I'm following your Rekluse install with interest. I'm on my 3rd Rekluse in a 2014.5 Gen 2, since about Oct '18. In my case, those fiber pads dissolved in between 1500 to 2000 miles and the clutch started to slip badly. Rekluse replaced the clutch after viewing the photos. I was using Amsoil Synthetic Metric Motorcycle oil for the first clutch and Mobil 1 Synthetic Motorcycle oil for the 2nd clutch. Both oils carried the recommended MA2 rating. Free play started at the recommended 1/8" then increased to 1/4" and in the end was a whopping 1/2". For the 3rd clutch, at the suggestion of my mechanic, I've switched to Kawasaki dino oil. At the time of the install of the 3rd Rekluse, I also had my mechanic install a set of stiffer Barnett clutch springs.
    I've got just over 1000 miles on the new clutch, the majority of it offroad. I still get an occasional judder when leaving a stop, just like with the other two clutches. The stiffer springs are noticeable but I've adjusted. In another 1500 miles I'll know if the issue has been licked."

    I didn't think the oil was it. Clutch springs? Not sure. I've long favored lower net spring force on pressure plates and have in many bikes removed two of the six springs (such as on my current Beta 390) for easier lever pull and less hyper slip-zone character. But that's when I am controlling the clutch and not a centrifugal element. In general I have found net spring force on clutches to be Overkill, being biased toward 'heavy duty' by default. Perhaps to be stupid friendly.

    And that just gave me a clue! The Rekluse is perhaps significantly clutch-pack height and adjustment sensitive, especially on a cable clutch bike as slack tends to open up at the lever as temperature rises, whereas hydraulic clutches reset when stroked and are more adjustment stable.

    I've got to think through 'free play gain' more as part of it isn't making sense to me. Going to re watch the two above videos.
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  17. ZachM1

    ZachM1 I'm a meat popsicle

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    @motobene I noticed your posts in the KLR thread. To be honest I only get involved with general mechanics there. Too many "opinions" come up with "fancy" mechanical parts there. It's been a couple of years & I deleted my post, but mentioning having a Lectron carb there started some flaming. So it's probably a good thing you moved the discussion here.
    #17
  18. renogeorge

    renogeorge Let's ride!!

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    Generally, auto clutch adjustment is definitely simpler and more stable with hydraulic systems vs cable clutches. The distinction needs to be made between the clutch pack/EXP/DynaRing style and the older pressure plate style. There are differences. The clutch pack style, wether using wedges or balls, relies on creating a gap in the clutch pack using the clutch actuating rod. This is done by manually pushing the rod into the throw out/ pressure plate, either with a slave cylinder set screw or cable adjustment/throw out shimming. In any case it’s all about he gap. Too big and there is lag when engaging, freewheeling on steep downhills and potential is here for slipping if AC can’t expand far enough to put full pressure into the clutch pack. Too small and stalling can still occur. FWIW
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  19. motobene

    motobene Motoing for 49 years Supporter

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    I appreciate your viewpoint.

    Posting entails risk and every one of us has whatever risk tolerance. My risk tolerance is high, I love to write:pynd , and I like being challenged. I love free speech and that means risk and I say my stupid thing and someone else says ther stupid thing and we challenge each other and learn. Thankfully, I have found few knuckle draggers frequenting ADVRider threads, and those who pop on scene as poser experts throwing flame balls can't handle the ensuing social correction and usually leave to become 'experts' elsewhere. The KLR Only thread is a good place but diving into the Rekluse auto clutch was too specialized for a general thread. And for me it's about a broader application anyway, with the KLR merely the entry point for learning.
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  20. ZachM1

    ZachM1 I'm a meat popsicle

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    I apparently awakened all the knuckle draggers with the word Lectron. Right there with you on free speech and risk. That's why I didn't have a problem mentioning "the carb". I'm usually pretty thick skinned and laugh stuff off easily, but that thread was going off the rails quickly so - gone. That and there are a couple of "expert" mods that are thin skinned with ban hammers at the ready. So I only contribute in limited ways since I'm definitely not an expert, but usually speak openly with my thoughts in the free world - which gets that ban hammer round here.

    I'll stop with this comment now about anything other than Rekluse to keep things on subject.
    #20