EXC (DDS) clutch in an SXF (with CS clutch)?

[Jim Cummings]

Hi Guys, I am trying to set up my SXF to be better suited for Enduro. My biggest complaint is the clutch is very heavy for low speed feathering so I am considering ways to get a softer pull clutch. I have had both EXC´s and SXF´s in the past but am trying to build a bike that is ok for MX and enduro so I dont need to own two bikes. I could go down the tried and tested Rekluse route, which may be my best solution but I would prefer to not "loose" the ability" to instinctively use the clutch, which I fear will likely happen to me if I get an auto clutch. I have always favoured the softer pull of the EXC clutches does anyone know if you can put an EXC clutch in an SXF? And if so what parts must you swap? I have a 2016 350 SXF, thanks for any help in advance:-) Cheers Jim

[mog]

Midwest engineering clever lever

[team FTB]

I'm in the same boat with a 2016 250xcf and would love to get a DDS installed. Please chime in with thoughts, suggestions and ideas. I have already installed the clake 2. It is better but not worth the price as you are limited to one finger clutch engagement and still pulling on the original clutch. It's a lighter pull, but not as light as a DDS. I tried to Midwest Mountaineering lover and that is not near enough. The Clake is lighter than the Midwest Mountaineering Lever by far.

[mog]

I had it on 350,250,150 , can't imagine wanting less weight ,you would have zero feel imo

[Jim Cummings]

Hi Guys, thanks for the suggestions. I could try a different lever, I am not against this but figure you are still going to be pulling on the same clutch so think what i am really interested in is knowing is it possible to change to a DDS clutch. The reason for this is my last Enduro bikes were a 500exc, 450 exc and a 350 exc all with DDS clutches that seamed to offer much more modulation, and a lighter pull. Now tbh I have never messed around with clutches before (other then changing worn parts) on either my mx or enduro bikes. But now that I have started riding a mx bike in the woods I just notice that its much easier to stall at low speeds. I have put this down to the clutch but wonder of it is perhaps as much to do with the flywheel enertia if thats greater on a MX bike then an enduro? I have gone up a few teeth on the rear cog so gearing is simalar to an enduro (at least down low). I just dont seam to  be as comfortable on the clutch?

[mog]

I think dds is a great system ,think it might he super expensive to do ?

[Jim Cummings]

@Mog TBH I´m sure it wont be cheap but before that I am not sure its even possible (thats why I asked on here as there is probably more knowledge here then at my local dealer!). My other option is a Rekluse. I doubt it will be much more then a rekluse and may well be a better option for me....

[mog]

Recluse will solve that problem once and for all ,I found them odd to ride ,I needed more time on it to get used to it

[eastreich]

It shouldn't be too much of an issue, when comparing the parts fiche for the two models.  They use the same clutch plates (except for count), and the primary gear ratios are the same.  Therefore "all" that should be needed are the outer basket, inner hub, 6 pins/sleeves that go between plates and inner hub, pressure plate, conical spring, hold down plate, damping plate/cushions and it's assorted parts, and one extra fiber and steel plate.  Don't forget that the clutch push rod is also different between the two.

Just from adding things quickly in my head it should run around $300 in parts (US of course, not sure in Norway) depending on where you get them.

Some parts are the same between the SXF and EXC-F, so those don't need to be replaced (unless you really want to).  Those are the throwout bearing assembly, clutch plates, and the bearing/sleeve that goes between the mainshaft and the outer clutch basket.  I would replace all of the clutch plates if the budget allows, but that is not always the case.

Edited October 1, 2018 by eastreich

[Drehwurm]

12 hours ago, Jim Cummings said:

Hi Guys, I am trying to set up my SXF to be better suited for Enduro. My biggest complaint is the clutch is very heavy for low speed feathering so I am considering ways to get a softer pull clutch.

The DDS clutch works awesome on the SXF, especially as the SXF already has the smaller 9mm clutch master (EXC 10mm) - buttery smooth one finger clutch. I'm actually using the heavier disk spring from the 450 with the 9mm master, but it is not mandatory; more a personal preference. Problem is the outer clutch basket (expensive) on the SXF has shorter fingers for the friction disks - so to fit the DDS parts you have to do some very careful measuring and have to have a full understanding of how the parts on the DDS work together. It's tricky and there is no room for error. Personally I used a Rekluse Core Manual DDS set that was modified to fit into the SXF.

There is another option though - KTM has used this setup (SX outer basket, DDS parts) on the 2018 Freeride 250F with only 7 friction disks - so if you fit the harder disk spring you are probably fine copying the parts from this setup: KTM spare parts freeride clutch

Last but not least the outer basket from a 350EXC-F should fit, but then probably also have to space out the clutch cover on the SXF or use a Rekluse cover from the auto clutches.

 

Michael

 

[Jim Cummings]

Thanks for your response Eastreich and Michael. This is excellent. So to clarify my understanding according to your notes. If I add all the original EXC DDS parts including the outer basket it should fit and work great BUT The problem is the outer clutch cover will contact the outer basket:-/ I assume this is fixable by running the EXC outer clutch cover or perhaps complete clutch cover? Or like you suggest a deeper rekluse cover. Do you know is there a difference between DDS clutches, for example should I choose the most simalar eg 350 exc 2016? Or is that the same clutch as is now used on the 2019 350 SXF?

Route 2 is go the freeride 250 f route. That sounds the most straight forward. I assume you suggest the stronger 450 spring as since its less friction plates it might slip?

Route 3 Like you Michael do something with the Rekluse core DDS. What modification did you have to do to make this fit the SXF, presumably it was something to do with shortening the splines?

Route 4 this is my own theory- What about installing a rekluse (exc) DDS clutch? Could this fit or be made to fit to go in the SXF. Presumably the same issue as the EXC outer clutch basket contacting the outer clutch cover, and you would need to also buy the longer actuator rod?

Cheers for all your help so far.

 

Cheers Jim

 

[Jim Cummings]

Ok for anyone who is interested I have been doing a bit more research (and answered at least one of my questions I had to Michael). I have been looking ta the parts diagrams and I can see I definitely could not use a EXC clutch cover inner or outer as it is quite different, so like you suggested Michael perhaps a Rukluse cover would give the clearance. However I have researched further and found out the 2019 350 SXF uses a DDS clutch, with the same clutch cover as the 16-18 models:-) All the part numbers for the DDS seam different to the EXC versions so it looks like I might be able to simply drop in the 2019 clutch. @ Michael could you look at this and see what you think. Could this be the easiest way?

[Drehwurm]

2 hours ago, Jim Cummings said:

However I have researched further and found out the 2019 350 SXF uses a DDS clutch, with the same clutch cover as the 16-18 models:-) All the part numbers for the DDS seam different to the EXC versions so it looks like I might be able to simply drop in the 2019 clutch. @ Michael could you look at this and see what you think. Could this be the easiest way?

The 2019 DS clutch is a different animal altogether - it is not "dampend" therefor only "DS" and that's why it has less height also. Also note that the 2019 DS clutch uses only 7 friction disks and a 300NM (!!!) disk spring. Nevertheless outer basket and primary gear are different to the previous generation so a retro-fit is at least questionable.

 

This should also answer your question route 2 - if the 2019 works with 7 friction disks, the 2016 should as well. The 2019 disk spring would fit the DDS parts.

 

Fitting the Rekluse DDS parts you need to take several critical measurements into account and adjust, the stock KTM DDS parts from the EXC are easier - this is with re-using the SXF outer basket. You can save some height with using button head screws instead of the stock hex head ones. In general you need to use the thinner 1mm steel disks to fit 8 friction disks with the SXF outer basket and then stack steel disks on top of the stack to compensate for the height of the inner hub DDS parts.

 

Michael

 

[Drehwurm]

Oh, just double checked - the Freeride 250F IS the 2019 SXF DS clutch minus the heavy spring. Now it should be clear which path to take ...

 

Michael

 

[stevo604]

I have a 2017 350 xcf and live in Squamish, BC. It is tight single track around here and I spend most of my time in 2nd gear.  

When I first got the bike the clutch pull was brutal and I would end up stalling all the time from hand fatigue. Since then I put in 3 Freeride springs and a Steahly flywheel weight and am pretty happy.  

 

 

[Jim Cummings]

@ Michael After some more research it looks like its allot more working making the EXC DDS clutch to fit so I am leaning towards your suggestion of the Freeride 250F 18/350SXF 19 solution. It is only DS but it should be pretty straight forward getting it to fit. The only difference I see between the F250F and the 350SXF19 is the spring ring (and obviously belleville spring) is a different parts number but otherwise the rest is the same. Do you have any comments on how a non damped version of this clutch would work?

Or do you think I am better off going for the 350 EXC parts (DDS) with one less friction and intermediate disk and the stronger Belleville spring? Do you think this would fit and not conflict with the clutch outer cover?

Also do you know what the difference is between the SXF 19 Outer clutch hub and primary gear over the earlier versions. I can only see the part numbers are different but dont find any actual info on any actual physical differences... Cheers Jim

Edited October 3, 2018 by Jim Cummings
thought of some more options

[Jim Cummings]

@ Stevo604 what gen freeride springs did you use on your 350? Cheers Jim

[Drehwurm]

For offroad use DDS or DS shouldn't make a big difference. Definitely go with the Freeride 250F parts (don't mix any parts other than the disk spring) as they are dimensioned to fit the 16-18 SXF outer clutch basket; this includes the Freeride clutch pack and most important Spacer #4. So you'd need parts #4,#5,#9,#11, #12 #14 and #18 (freeride clutch pack). The stiffer disk spring and 6 M5x25 button head screws. You also need to make sure that the lock nut #10 bottoms out on the inner clutch hub and NOT on the splines of the drive shaft.

I don't know about the differences on the 2019 parts.

 

Michael

 

[stevo604]

I used the 2016 freeride clutch springs...Check out Rocky Mountain's OEM part finder...