Why are there two types of clutchs?

[skipro3]

Hi All. I just pulled my clutch to send back to have EFM make it into an auto clutch when I noted some differences in the shop manual. Page 5-2 shows an exploded diagram with the clutch spring holder as a four spring unit and then on page 5-6 and on page 5-12 are photos of the clutch spring holder and these are five spring units. I have a 1999 KDX220R and it has the four spring unit. Any idea what years, models, etc are 4 or 5 spring units and also why the change up? Is one better than the other? Using same weight springs, I would think the 5 spring unit would be difficult to pull in or the 4 spring would be a one finger clutch.
Thanks for any info on this.

 

[canyncarvr]

You're assuming the manual to have some relationship to fact. That isn't necessarily so.

I don't know there isn't a 5-spring clutch for the kdx. I do know there is more than one spot in the manual where the pictures seem to have come from the shelf labeled 'one-each-bike pics'...they either don't apply or they contradict the text.

 

[skipro3]

Gary at EFM is aware of the differences and says it is based on year of the KDX. He also told me it makes no never mind for him, he can modify both. Yee Haww! Can't wait to test out the auto clutch. BTW, the KDX clutch actuator is located on the right side and therefore is removed for the mod. so no hand clutch to work. My bud's KX500 clutch actuates from the inside, (even the clutch cable is located on the left side of the motor) and he can therefore still have his hand clutch if he wants. Next, I will fab up a hand brake lever for the rear in place of the clutch lever.

 

[canyncarvr]

re: 5 vs: 4

Something to file away for some future reference (or something else to be forgotten?)

Doesn't the EFM website say the manual clutch operation is retained? Is that NOT an option for the KDX?

What does it matter whether the actuation is right or left? Well, probably more a matter of activation from the INside or the OUTside, cuz the EFM clutch is considerably different in construction on the 'out'side.

I wouldn't want to do without it.

A rear brake lever would be quite a chore, I'd think. Some kind'a mechanical goober that would activate the master cylinder? A dual master cylinder setup? Then you would need a check valve of some sort? ...which would interfere with normal fluid movement during release.

Have fun!

p.s.
When are you headed out on your coast trip?

 

[skipro3]

Doesn't the EFM website say the manual clutch operation is retained? Is that NOT an option for the KDX?

The site is off line and has been for some time, but it never even listed the KDX at all. Garry's personal ride is a KDX though and that is good to know. It is not an option on the KDX. Garry will plug the hole in the clutch cover if it's sent in with the clutch. If anyone else does this mod, be sure to remove the small needle bearing that the lever uses inside the clutch cover. While tight now, it won't be with a little heat to the cover. Then IF it came out since no more lever to hold it in, there could be disaster.

What does it matter whether the actuation is right or left? Well, probably more a matter of activation from the INside or the OUTside, cuz the EFM clutch is considerably different in construction on the 'out'side.

That about answers it. The KDX clutch actuation is on the "business" end of the automatic components, where as other bikes, AKA KX500's have the clutch actuated from the back side of the clutch. BTW the KX500 does not have a seperate clutch cover. The whole side cover comes off as one unit. Therefore, the extra space needed for the automatic components requiring a spacer between the case and the cover, will cause the kickstart lever not to mount. The fix? the portion of the side cover protecting the clutch will be cut off, and either a spacer welded on and the cover re-welded, or a cover off some other model bike will be welded on. (Then there would be only one weld ring, not two.) Think about it and try to visualize that a spacer would be twice the welding that a deeper cover would require.

I wouldn't want to do without it.

A leap of faith so to speak. I'm wreckless, but from everything I've heard, a risk l'll take. The KX will be able to retain it's clutch lever but from what I've read on searches here, if someone pulls the clutch lever a couple of times with the motor off, it will hose up the auto clutch and ruin your day. This will be impossible for the KDX to have happen.

A rear brake lever would be quite a chore, I'd think. Some kind'a mechanical goober that would activate the master cylinder? A dual master cylinder setup? Then you would need a check valve of some sort? ...which would interfere with normal fluid movement during release.

I need to do more research but I've read here on DRN that other makers of auto clutches have kits to make the rear brake a hand brake. Looking at my rear master cylinder, it seems that all I need is a bracket to hold the cable sleeve and fabricate a longer pin that the brake petal uses to attach to the master cylinder and machine it to capture the cable ball end.

Have fun!

That's the whole point, isn't it? It's all fun, the wrenching, the modifying, the riding, the trials and errors too. You bet I'll have fun and I'll let you know how it turns out as well.

p.s.
When are you headed out on your coast trip?

New job you know. The trip right now is going to be short notice when I find a break and call in "sick" for a week. In the meantime, August 6th we (me and the wife on the Kawasaki Voyager, my KX500 riding buddy and his wife on his BMW touring whatever model) are headed up the Feather River to Lassen National Park. Most trails are starting to open now that the snow is melting quickly, and it's a great place to hike and fish. I did take one trip up the coast to Gold Beach to take a jet boat ride, but it was also just a 3 day weekend.

 

[YZ165]

Check out the Lockhart-Phillips web site or catalog. They have a "thumb" lever that has a built in master cyl. It bolts to the bars like a clutch lever. You can get it for the left or right side I think. I've seen them on roadrace bikes. Cool idea for those right hander's. Not sure how they stop the fluid from returning to the other master though. It's probably a pressure actuated valve that only allow's fluid to go backwards if there is no pressure on the unit. If it's presurized from either side it cuts of the other and dosen't allow fluid to pass. Just a guess. Anyway, the cable thing might be easier, but you'd have to pull pretty hard on the lever. My .02 for what it's worth.