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Grabby/Not fully disengaging clutch. 08'450 XCF

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Just took the new to me 2008 450 XCF out for its 1st D36 cross country race this past weekend. Up till now I'd only ridden it twice a few months ago for about 45 minutes and it was running super lean and boiled over both times. Decided to put some love into it before racing.

Installed:
Dirt Tricks Cooling Fan (no more boiling!)
Motion Pro Fluid Recovery System
JD Jet Kit (what a difference!)
No Toil Backfire Screen Eliminating Air Filter Kit
Dirt Tricks Cam Chain Tensioner
MSR exhaust heat shield
MSR Clutch Slave Cylinder Guard and Chain Knockdown Bar
Tugger Strap (can't believe they built a bike with zero hand holds to move it around!)
Pro Taper PillowTop Grips

The mods worked great and I was really stoked on the motor, chassis and suspension.. big upgrade from my 98' YZ 400F.

BUUUUUT..... The clutch is suuuuuuper grabby. In fact I have to ride the bike for about 10 minutes before I can stop, put the bike in neutral and put the bike in 1st gear without the bike lurching and stalling because the clutch doesn't fully disengage.
Even an hour into the race, the clutch does not completely disengage when squeezed all the way in and the motor still pulls just slightly. Then the clutch engagement isn't smooth when easing the lever out. All this combined with a pretty stiff clutch lever pull really hurt my control in the tight technical stuff and wore out my left forearm.

Soooo... does anyone have any advice on tuning the clutch for better control and or easing clutch lever pull? I've checked the mineral oil fluid level, and it's good, but I'll be flushing the system with new fluid this week. If that doesn't help, maybe aftermarket clutch plates are in order?
 

Edited by WhiteEagle78

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I am taking a stab because I had a similar issue with a bike years back.....have  a look at your clutch basket.  I am guessing it has grooves worn in it and may be time to replace it.  a warped/worn clutch plate could certainly cause you grief as well.  Perhaps the clutch is simply not disengaging completely and bleeding the line may help if there is any air in there preventing full range of disengagement?  Also, make sure you are using the proper oil for the bike.  If I recall anything with friction modifiers are not recommended......but dont take that to the bank because I have not referenced KTM directly on that.  I am simply making a general statement from something I recalled from memory.  But make sure you are using oil up to recommended spec no matter the brand.  

 

I hope one of these suggestions leads to the source of your issue.  Good luck......

 

PaulP

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The clutch in that bike is really, really grabby until you really warm it up, which for me, took about 10-15 minutes of riding.  Then it was perfectly fine.

 

That's just what they do.   No harm, no foul.

 

Get a rekluse.  That will cure the problem and give you some other advantages.

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I am taking a stab because I had a similar issue with a bike years back.....have  a look at your clutch basket.  I am guessing it has grooves worn in it and may be time to replace it.  a warped/worn clutch plate could certainly cause you grief as well.  Perhaps the clutch is simply not disengaging completely and bleeding the line may help if there is any air in there preventing full range of disengagement?  Also, make sure you are using the proper oil for the bike.  If I recall anything with friction modifiers are not recommended......but dont take that to the bank because I have not referenced KTM directly on that.  I am simply making a general statement from something I recalled from memory.  But make sure you are using oil up to recommended spec no matter the brand.  

 

I hope one of these suggestions leads to the source of your issue.  Good luck......

 

PaulP

Before I bought the bike I actually called my local KTM dealer to ask about any potential problems with this year and model.  He said that all the internet posts about necessary oil pump rotor upgrades and and ditching the stock hydraulic cam chain tensioner were pretty over stated and he'd never seen a pump failure and only a few bikes that needed a cam chain tensioner upgrade.  However, he did mention that clutch basket failure had been an issue and recommended upgrading to a Hinson basket if I were to rider really hard. 

 

I have not pulled clutch to inspect it yet, am hoping to make it through the next 4 cross country races before doing so.  I think it's reasonable to expect that there could be groves worn into the fingers of the basket preventing the disks from disengaging easily as you suggest.  This was actually an issue on my 1998 Triumph Sprint 900, and I smoothed them out with a jewelers file.  !5,000 miles later it's still working smoothly. I think a Hinson clutch basket will be in order for the KTM though, it's just going to be a while since that's a good stack of change!  I did bleed the clutch system (no bubbles, but it was dirty) and the problem still persists.

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The clutch in that bike is really, really grabby until you really warm it up, which for me, took about 10-15 minutes of riding.  Then it was perfectly fine.

 

That's just what they do.   No harm, no foul.

 

Get a rekluse.  That will cure the problem and give you some other advantages.

Its really, really grabby indeed until its fully warmed up, but even then its still a little grabby, which really screws with my control in the tight, clutch intensive spots.  In my many years of riding Honda's and Yamaha's, I've never experienced this issue.  It has, for the very first time, actually gotten me to consider a Rekluse auto clutch.  I think I need to ride a KTM equipped with one before I could ever fully consider spending the money on one though.  Call me old school, but the thought of giving up any of my clutch control still makes me cringe. Maybe I'll be pleasantly surprised when I actually try one for the first time though.

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Well I am more of a moto guy but I did have a Core Exp on my 09 Honda and the truth is with that model you do not even know its there.  The clutch feel and acts EXACTLY like your stock clutch except below a certain rpm (dictated by the wedges you select....does not use the little pin balls!) it completely disengaged.  As you add throttle it reengages...how smoothly again is determined by the wedges.  It is really an excellent system.  If you want it to be 100% stock type clutch there is a pressure plate you can get that just pops on in a few minutes and your back to a stock clutch.  I would call the Rekluse guys and talk to them...they are very helpful and the install is really very straight forward.  I do recall mine using the stock basket though....so if your does need replacement that will be an additional item you would need to get.  

 

The only thing that I found weird is that no matter what gear your in.....the big is always in "neutral" when idling or on the stand.  YOu cant put it in gear and "lock the wheel".  So you have to be aware of the gear you in when you start the bike or just sitting.  But overall I think its an excellent advancement overall.  You cant really even tell its there at the clutch lever but you gain all the benefits of a centrifical type clutch.

 

Ok...advertisement over..lol!  

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Its really, really grabby indeed until its fully warmed up, but even then its still a little grabby, which really screws with my control in the tight, clutch intensive spots.  In my many years of riding Honda's and Yamaha's, I've never experienced this issue.  It has, for the very first time, actually gotten me to consider a Rekluse auto clutch.  I think I need to ride a KTM equipped with one before I could ever fully consider spending the money on one though.  Call me old school, but the thought of giving up any of my clutch control still makes me cringe. Maybe I'll be pleasantly surprised when I actually try one for the first time though.

I had an 08 450xcf that I recently sold.  I used it ride wide open desert as welll as some pretty rocky single track.   I had that thing completely pimped out before a blown engine did me in.

 

Clutch issues were most important on that bike.    I put the heavier flywheel weight on it  (8 oz)  and that gave me much more control at low speed and stopped the excessive stalling. Then I added a rekluse pro.  That completely fixed the clutch grabbing issue.   I love the rekluse pro.   I added the heavier tungsten balls to it and set it for low/hard engagement, which means that I was basically using it as an anti-stall device only.  You can tune the rekluse however you want and you still can override everything with the clutch lever.     The way mine was set up, it didn't feather the clutch much and I had to control it with my left hand.    I LOVE the rekluse.   

 

So to better control it, I changed my clutch master cylinder to to a magura 9.5mm  (amazon) and I added the midwest mountain engineering clutch lever.   I was one finger clutching all day long with no problems. 

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Thanks guys, some good advice. I'm going to strongly consider a recluse in the future and will start doing some research in which one would work best for me. I like the idea of using the relish as an anti-stall device and retaining fully/nearly full control of the throttle.

I think that in the next couple weeks I'll be looking at upgrading the clutch master cylinder and installing the midwest mountain eng. clutch lever (or something similar) to get a more controlled lever feel.

Thanks again!

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Its most likely the basket, things reseat themselves when they get hot. I have the opposite problem with my 2 stroke, when it gets hot, the clutch is grabby when cold its not. My basket and plates are shot, I'm just waiting until it stops working before I replace the entire thing, I can live with it being grabby. 

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Its really, really grabby indeed until its fully warmed up, but even then its still a little grabby, which really screws with my control in the tight, clutch intensive spots.  In my many years of riding Honda's and Yamaha's, I've never experienced this issue.  It has, for the very first time, actually gotten me to consider a Rekluse auto clutch.  I think I need to ride a KTM equipped with one before I could ever fully consider spending the money on one though.  Call me old school, but the thought of giving up any of my clutch control still makes me cringe. Maybe I'll be pleasantly surprised when I actually try one for the first time though.

 

like others have said its probably your basket finger being grooved. That being said i quoted your post for a reason, Id like to point out how you said you dont want to give up your clutch. All i can say is if the thought of putting a rekluse auto clutch in your bike has crossed your mind, DO IT. I promise you there will be no disappointment at all, and the clutch works as good if not better when you use it as a manual clutch than when it was stock. Ill admit i was definitely on the fence about buying a 900 dollar clutch for my bike but i bit the bullet and did it. I am amazed man, honestly. This clutch is awesome and so far as durable as can be. I got the adjustable slave cylinder with mine for ease of adjustment, naturally as the plates wear and thin out youll have to make slight adjustments to compensate to keep the clutch working properly. Ive got 3 two hour long hare scrambles plus many days of riding and practicing and i have yet to make an adjustment. I dont mean to sound like i work for rekluse lol but honestly the core exp 2.0 is the most effective mod ive ever used on a dirt bike and im 100% pleased with my purchase.

Edited by Woodsweapon350

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mines grabby until warmed,so not much of an issue,,,,,with the recluse,can you bump start??this bike has no kickstart,only bump start backup  or jumpstart if you have another bike handy with a battery.d1

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So to better control it, I changed my clutch master cylinder to to a magura 9.5mm  (amazon) and I added the midwest mountain engineering clutch lever.   I was one finger clutching all day long with no problems. 

 

 

Well.... I had a little slow speed spill that resulted in breaking the stock clutch lever clean off the bike during a race this weekend, would have had a sold 2nd place finish if I could have picked'er back up and finished 1 more lap.  The lever didn't actually break, the actual master cylinder where the lever goes into it sheered right off from the rest of the master cylinder body!  My dumb as fault really, I'm running full hand guards, but had not yet run Teflon plumbers tape between the bar and the master cylinder mount yet so it would slide and rotate instead of breaking during a crash. Now I'm rushing to get a new master cylinder before next weekends race.  The stock Magura master cylinder has a 10.5mm diameter plunger, my understanding is that going to a 9.5 would make the pull slightly easier but it also effects how the clutch engages / disengages?

 

What difference did you find between the 10.5 mill. and 9.5 mill?          

 

I'll be ordering the Midwest Mountain Engineering clutch lever tomorrow.  Looks like a damn good product.  I may just get a stock 10.5 mill. master cylinder instead of the 9.5 if I can get it here faster and rely on the Midwest. Mtn. Eng. clutch lever to reduce the clutch pull by roughly 50%.  Sure will be great to have a shorty lever again as well.  My YZ400F has a shorty lever and I have sooooo much more control of the motorcycle in the tight stuff when can have 2 fingers wrapped around the grip and two working the clutch.

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