Kaybeach007

Member
Dec 7, 2004
13
0
I enjoy highly technical, tight, wet woods rides. This is murder on your left hand, having to constantly control the clutch. 45 minutes to do a 3 kilometre overgrown, rock strewn, muddy river section is where I thrive. A soft, easy clutch is a must. Without getting fancy and going off and making the spares dealer rich, here's a small cheap improvement which can improve your clutch control on practically any make of bike.

Disconnect the clutch cable from the clutch release shaft on the RT side of the motor. Remove the RT clutch housing cover and withdraw the clutch release shaft, careful not to damage the oil seal. Measure from the centre of the shaft out to where the cable clips into the release pivot. On my 98KDX200 it is about 30mm give or take a metre. What you want to do is increase this length as mush as you can without the pivot arm of the clutch release interfering with the carb or cylinder housing. Measure on the motor how much room you have and decide on how much to add to the length of the pivot arm.

Mark the shaft and pivot plate so that you can line them up later again. Carefully grind off the weld on top of the flat pivot arm plate where it is welded to the shaft. Hit the shaft out of the plate with a punch. The top of the shaft has a 8mm diameter, remember this.

Now weld the flat pivot plate to a similar extension plate. Put gusset welds down the side for strength. Try to use a MIG or TIG welder as they have better power control and generally give a better weld. Ensure that everything is straight and flat. Now drill a 8mm hole in the end of the extension plate and press onto the shaft, ensuring the marks you made earlier line up. Weld the plate to the top of the shaft as it was originally.

Paint and assemble. Try and gently bent the hollow threaded guide where it mounts onto the motor as you will now have a slight bend in the cable. Use heat and be gentle. Service your cables by hanging them and spraying WD40 down their length several times.

Simple physics dictates that the longer the lever, the less force is required to do the work. I went from 30mm centres to 60mm centres. I only need one finger to operate the clutch, this means I could shorten my clutch lever whivch means less to break when you fall and the clutch lever never interfers with your other fingers as they desperately hold on for dear life.

A cable is always more reliable that a hydraulic system and from what I have read the aftermarket hydraulic clutches are no softer than cable. After 45 minutes in a river bed most of the guys I ride with are exhausted, hardly able to hold on the the handlebars (including the KTM guys with hydraulic systems as standard). I get very little shoulder and upper back fatigue anymore and absolutely no arm pump. It cost me a six pack of beer which I had to share with the guy while I used his MIG welder.
 

canyncarvr

~SPONSOR~
Oct 14, 1999
4,005
0
Simple physics dictates that the longer the lever, the less force is required to do the work.

Yes. And also, you don't get something for nothing...or for every action there is an opposite and equal reaction.

Which is to say..the longer lever will also have to be pulled thru a longer arc (more lever) to get the same amount of movement the shorter lever did with a shorter arc.

Glad it worked well for you.
 

DerekLee

Member
Oct 17, 2005
1
0
Well, how would it benefit to drill a new hole on the lever closer to the pivot point? as compared to this modification. Like the raptor clutches?
 

Woodsquest

I love DRN!
Member
Dec 15, 2004
94
0
lepper said:
Or... you could just go with a EFM autoclutch and put your balls in a box up by your filter oil.... :laugh:

hey Hey HEY!!! :| :pissed:
I know where you live!!
 
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