Auto clutches

[MalMember]

Thought I start a thread for info on auto clutches.

There are two main brands for trail bikes. Rekluse and Revloc. I found another brand called EFM auto clutch from the USA, but I don’t know anything about these.

http://www.rekluse.com/ Suttos in the importer for these.

http://www.revloc.com/index.cfm/id/2/Dirt-Bikes/

http://www.revloc.com.au/

http://www.efmautoclutch.com/index.shtml

I had a Rekluse Z-start pro in a 300 2 stroke kick start bike. I posted a review on it HERE.

I don’t have one on the bike I have now. But if I went back to a 4 stroke electric and kick start bike I would go an auto clutch again.

I noticed on the rekluse web site that they now do a similar product to the revloc dyna ring.

STM posted a great review on the Rekluse Core EXP .HERE

Lefty installed a Revloc dyna ring and posted a review HERE

Post up if you have or had one. Brand and model if you can and likes/dislikes of the clutch.

So use this thread to ask questions or post knowledge on auto clutches.

And yes it is CHEATING. :laugh:

[scott bockingMember]

Good thread Mal.
It seems there is a lot of development going on and more options than ever. I was lucky enough to be given my Rekluse and its installation as a prize thanks to Sutto’s. I was not in the market for one but after using the Core EXP I am convinced of the relevance of auto clutches. I would be really keen to hear from the experts the difference between the Z start pro and the EXP. Mal mentioned that he had a few frustrations in the past and one was the adjustability of engagement. It seems they may have addressed this with the EXP as I had no issue.

As for cheating where do you draw the line? Is getting your suspension tuned cheating. Is running tyres specific to your terrain or using EFI cheating? Our sport is experiencing a technology boom that we all stand to benefit from.

STM

[Geoff ForshawMember]

Hi Mal,

Yes good thread mate for those who are in the market.

Cheers,

Lefty

[timMember]

06 550 Berg fitted with original Rekluse z-start, this version required the clutch basket be modified
08 450 Berg fitted with Rekluse z-start Pro, much easier to install
Both units very durable (250+hrs on each unit) and once set operate very well.
Both bikes still stall sometimes under certain conditions, main problem with this is caused by aggresive application of the throttle, with correct carbi tuning especially with the pumper unit, will overcome most of this
Other issue is again over aggressive application of the rear brake can cause stalling
Overall these issues are minor and not really the fault of the Rekluse
I would recommend one and will be installing one in my next ride.

[MalMember]

I’d like to hear from the experts as well STM. The main differences I see are less moving parts in the EXP and easier adjustability and the clutch feel.

AS for the cheating part. I put that in for the no believers. :laugh: I’m all for the technology boom. I bought a EFI bike in 2007 and my mates packed tow ropes in their bumbags cause they thought an EFI bike would never handle the bush. 12000 kms later and no EFI issues with the bike at all. Now everyone’s on the EFI band wagon.

I’m interested to learn more about the revloc. How their auto clutch operates and the dyna ring. The new rekluse EXP clutch (not the Core EXP) looks like it does the same thing as the dyna ring.

Lefty I forgot to put your review at the top. Sorry mate, I will fix that up.

Is the Dyna Ring like an expanding clutch plate? The rekluse one looks like that on their web site.

Medogrocket your a font of knowledge as usual. Your 550 is what satrted me thinking about the rekluse.

[Adam RodgersMember]

Whilst we are asking about technical details about auto clutches I would like to ask if there is increased wear on the clutch throw out bearing on the expanding clutch plate types. The system relies on the clutch being held partially disengaged by cable tension allowing the expanding clutch ring to do its thing when the engine revs are low. When the revs are high does the expanding ring expand enough to release the load off the clutch throw out bearing?

I still see importance in selecting the correct gear for the terrain being travelled as a too high a gear with low revs and a slightly slipping clutch on fewer wear surfaces is likely to promote faster wear and as mentioned before more heat.

My 20 cents worth, and I have more coins in my pocket

PS I like the idea I too like technical advances that can make riding more enjoyable

And I need all the help I can get :laugh:

Adam.

[Scott TyszkiewiczMember]

What is the technical difference between Core EXP and z-Start Pro?
A z-Start Pro clutch differs from a Core EXP clutch in two significant ways: how centrifugal force is generated and how the clutch lever disengages the clutch.

Centrifugal Force – Balls vs Wedges
A z-Start Pro clutch uses 24 to 30 ball bearings (depending on model and configuration) to create centrifugal force to engage the clutch. The advantages of ball bearings is that you can add or subtract balls or even change from a lighter to heavier ball material to easily change the engagement characteristics of the clutch. The disadvantage to balls is that they are small and can be easily dropped when installing or maintaining the clutch.

A Core EXP clutch uses 6 “wedges” to create centrifugal force to engage the clutch. A set of “heavy” wedges is included in the kit and a set of “light” wedges is available as an option to change the engagement characteristics of the clutch.

Disengaging the Clutch – Overcoming Centrifugal Force vs Overcoming Springs
The z-Start Pro clutch uses a centrifugal pressure plate that moves towards the clutch friction disks for engagement. To manually override the clutch, the clutch lever pushes against the centrifugal force to disengage the clutch. At low RPM, the centrifugal force is lower so the clutch lever pull is light. At higher RPM the centrifugal forces engage a spring and the clutch lever pull is similar to a stock clutch.

The Core EXP clutch uses centrifugal friction disk that moves towards a spring-loaded pressure plate, similar to the stock pressure plate, to engage the clutch. With the Core EXP clutch, there is no centrifugal force device between the clutch lever and the pressure plate, so clutch lever feel is just like a stock clutch whether RPMs are low or high. With Core EXP, precise manual modulation of clutch engagement using the clutch lever is possible at any RPM.

What is different in a Rekluse EXP Clutch?
The Rekluse EXP Clutch is designed to work with most of your stock clutch components. A single centrifugal friction disk replaces 3 of the stock friction plates, converting most clutches from an 8 friction plate clutch to a 6 friction plate clutch. Heavy-duty clutch springs are included to maintain adequate clutch clamping force using fewer friction plates. A Rekluse EXP Clutch can be manually disengaged with the clutch lever, but the clutch pull is heavier than the stock clutch.

[Scott TyszkiewiczMember]

Will an auto clutch wear my parts faster?
No. Because Rekluse Clutches are more efficient at clutching than the human hand, your clutch parts will last as long or longer than with a conventional clutch.

Can I bump-start with an auto clutch?
All Rekluse automatic clutches can be configured to bump-start the engine in the event your normal starting system fails. None of the Rekluse automatic clutches can be configured for bump-starting quickly and easily enough to use bump-starting as a regular method for starting the engine, rather bump-starting can be used to get you home in the event your normal starting system fails.

Hopefully this clears up some confusion.

Cheers
Scott

[Geoff ForshawMember]

Hi Gents,
Just thought that i would show some pics of the Rev-Loc Installed.

Rev-loc Dyna Ring in std clutch basket
[attachment=2614]2011-07-06_15-19-51_950.jpg[/attachment]

Rev-Loc Dyna Ring Assy
[attachment=2615]2011-07-06_15-34-31_15.jpg[/attachment]

Adding spacers supplied to create the correct clearance (1.0 – 1.5mm)
[attachment=2616]2011-07-06_15-35-36_872.jpg[/attachment]

Rev-Loc Dyna Ring Installed with pressure plate
[attachment=2617]2011-07-06_15-47-02_428.jpg[/attachment]

Measuring correct clearance with feeler gauges
[attachment=2618]2011-07-06_15-51-00_366.jpg[/attachment]

Cheers,
Lefty

[Geoff ForshawMember]

Hi Mal,

Yes the Dyna Ring is effectively like an expanding clutch plate. You will notice that it has 6 grub screws. Under these grub screws there is a spring. You can adjust the amount of drag/bite depending on the number of springs installed. You can have a minimum of 3 springs to a maximum of 6 springs. I have 6 springs in mine and it drags slightly at idle. The centrifugal force must overcome the spring rate in order for the clutch to engage/expand. You will notice it uses balls inside.

Cheers,
Lefty

[Scott SouthwellMember]

Some good inf on this thread. I think the newer style Dyna Ring and EXP clutches, with there more affordable pricing and simplicity of fitment will help make auto style clutches become more mainstream.

[MalMember]

Thanks for the pics Lefty. As they say a picture tells a thousand words. Seems to be a nice simple system.

Scotty I think you’re right with the price of the Dyna Ring and EXP a lot more riders will use them.

I wonder if us trail hacks need the full blown auto clutch or the Dyna ring/EXP will more than enough for our application and the pro hard core blokes would use the full autos as it replace the whole clutch system with heavy duty parts. Just a thought. Maybe TISCO/Suttos has some insight.

TISCO – great write up mate, explains a lot and easy to understand.

[Scott SouthwellMember]

Another benefit I can see of the newer style Dyna Ring and EXP clutches is as they look easy to fit you could easily convert the bike back to a standard clutch for a ride if you wished. It would be possible to have two clutch packs, one standard and one auto and change for the one you desire for each ride.

[Scott TyszkiewiczMember]

The EXP 2.0. For the Basic trail rider the EXP clutch is fine, it is still a full Auto Clutch and is a similar design to the Dyna Ring but uses Wedges rather then Balls so has a smoother engagement.

The Z-Start Pro. You can still use your clutch lever but loose some feel, This clutch is more durable for the more advanced rider and also the Amateur.

The CORE EXP. If your an Amateur or a Pro this is the best of the best, With all billet parts its light weight and strong and Fully Tunable to Rider Preference & Terrain Conditions. The result is clutch engagement and disengagement response that is unparalleled by any previous auto-clutch. Throttle control is increased dramatically while maintaining increased clutch performance at low to mid RPMs. With the increased response, a wider array of tuning options become available while further reducing the possibility of “pop” stalls.
And also comes with billet clutch cover.

*Prices do vary with the Aussie dollar*

[scott bockingMember]

It was the smooth engagement that blew me away. I have not ridden a ball style Rekluse but I can say that the wedge system gives amazing drive.

STM

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