XS650 Clutch Worm Actuator experiment & tidbits

Is it expansion of metal causing a change in tolerances?
Yes, the actuator throws a really small amount of travel to begin with , and getting hot throws those tolerances out of whack. Some of these other guys can tell you exact measurements, heck it’s probably already in this thread somewhere. How fast it gets hot really depends on your conditions. I’m already in a hot climate. If I get in a lot of stop and go traffic and sitting at traffic lights, it can spike really fast. Some guys have a lot of issues with finding neutral, others none at all.
 
Wow, DogBunny, that worm's got quite a history! Makes me wonder even more why Yamaha didn't use the XS500 arm geometry on the XS650s.

Here's another coupla questions. Why does the MikesXS worm have the finer pitch? Is this patterned after another different worm design?

I realize this is a very old thread but I thought I would answer the design change question. The change is most likely due to Patent Rights. As long as the original manufacturer continues to renew patents on a part the only way an aftermarket manufacturer can offer an exact duplicate is to pay royalties even if the original is no longer manufactured.

So to get out of paying fifty cents or a dollar on every one they make they change it just a bit.

I first noticed this in aftermarket automotive body parts. No matter how old the car or how much you pay for the parts the aftermarket parts are never exactly like the factory parts. At first I thought they were just making cheaper parts but some of the changes aren't any cheaper at all. For example, if you have a late model Mercury Marquis or Ford Crown Vic with an aftermarket header panel there will be a weird, explainable hole at the bottom of the grill that isn't found on the factory header panel. Since putting a new front end on my Mercury a couple of years ago I'm clued into it on every Marquis and Crown Vic I see.

I replaced a headlight switch in my Dodge truck recently and the aftermarket switch had an extra bend in the bracket that served no purpose and probably required more work to make. But I guess labor is cheaper than royalties.
 
TwoMany.
For starters, thanks for this thread and all the work you put into it. I must have read it a hundred times since you first started your project in 2013.

I've had my '83 XS650 for about 15 years now and the clutch has always been hard to pull. And thanks to a 2 piece clutch rod and normal wear and tear it only got harder over the years. Add to that the Arthritis that has long been a part of my life and finally I just couldn't take it any more. It was resolve the issues or give up riding as a Social Security check won't allow the purchase of a new motorcycle.

I began with a set of Barnett discs because Barnett is the only company manufacturing clutches for the XS that are guaranteed to work properly with synthetic oils. I'm not saying other brands won't but they don't say so on their websites and never replied to my e-mails.

I installed a new 1 piece pushrod from MikesXS. Apparently Mikes has solved the problems they had with their pushrods back in 2013 because mine works fine.

I installed a new bushing and new seal. Yep, I had to do the seal twice but the second time it took. No leaks.

Forget the cable from MikesXS, I tried it, worked better than stock, but it is too short inside and has no room for adjustment. I replaced it with the EZ Pull from 650 Central and the adjustment problems are solved.

My clutch actuator (worm) came from MikesXS but I made a bolt on extension that adds roughly 1/2" to it's length. I wanted to weld it like you did but my welding skills... I weld some things but thin steel tends to just burn up. I used lots of Loctite on the 2 bolts that hold the extension on the clutch actuator. I used a 1/4-20 x 1/2 bolt in one of the holes but as the 2 holes were so close together I had to use a smaller bolt (maybe a #6) and a bushing I cut from a piece of 1/4" copper tubing in the other hole.

To make sure the cable doesn't rub the inside of the case I used a Dremel tool to grind a chamfer to the inside of the hole where the cable passes through.

After talking with MMM at 650 Central I took his advice and shortened the clutch return spring on the actuator just a tad so that the clutch snaps back when you let it go. Then I buttoned everything up, adjusted according to specs and....

Woah! I've got a 1 finger clutch that even old arthritic fingers can pull!

Thank you TwoMany, you've added years to my riding. And if I can't ride then I can't think of any reason to keep breathing.
 
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... I must have read it a hundred times since you first started your project in 2013...

Oh, the agony.
Glad you enjoyed it.
Yeah, it was an exploration into the unknown, discovery. Everybody got involved, we're all still learning here. I really enjoy the collaboration aspect.

The MikesXS worm will get you an easier pull, but at the expense of pressure plate travel. Ditto with the EZ-pull cable, and your arm extension. Check for full clutch disengagement when you get 'r done...
 
Hey TWOmany, you seem to be the worm gear and all associated parts guru on this subject.
I spoke to MMM at 650central, he told me to do the return spring loop mod, I assume to tighten things up but couldnt this also be done with a shorter spring vs doing the mod?
I will be trying one of his ez-pull cables as well.
Thanks
 
Hey TWOmany, you seem to be the worm gear and all associated parts guru on this subject.
I spoke to MMM at 650central, he told me to do the return spring loop mod, I assume to tighten things up but couldnt this also be done with a shorter spring vs doing the mod?
I will be trying one of his ez-pull cables as well.
Thanks

I did the worm gear mod but it worked even better after I switched from the Mikes XS one piece rod to TwoMany's one piece aluminum rod. The Mikes XS steel rod does not expand and contract at the same rate as the aluminum rod Steve sells causing your clutch adjustment to change after the bike warms up.

I bought the EZ Pull cable but it wouldn't fit in the clutch adjuster bolt on the handlebar so I had to go back to the Mikes XS cable I was using. But with the worm gear mod it did great until I blew the engine.
 
I will wait for 2many to respond, as I would also like to find out how to get a keeper like he made to increase the size of the shoulder on the ez pull cable
 
:twocents:

Motion pro cable! properly oiled after purchase, smooth, no sharp bends, routing.
Cleaned greased stock worm parts (check that nylon hasn't cracked)
stock push rod.
Rebushed or new clutch perch/lever, the clutch lever hole AND the bolt is usually badly worn, reducing travel and increasing effort.
It will work great. :devilish: is in the details.
I've set up at least 8 XS650's this way, they all work great.
 
:twocents:

Motion pro cable! properly oiled after purchase, smooth, no sharp bends, routing.
Cleaned greased stock worm parts (check that nylon hasn't cracked)
stock push rod.
Rebushed or new clutch perch/lever, the clutch lever hole AND the bolt is usually badly worn, reducing travel and increasing effort.
It will work great. :devilish: is in the details.
I've set up at least 8 XS650's this way, they all work great.

Yeah, what he said.
I did a whole bunch of experimenting and testing components ( outlined in this thread ) and hands down, the single biggest gain in ease of use, came from the Motion Pro cable.
 
So does the motion pro have any bend coming out of side cover, I dont seem to find the correct one on line, every site I go to has a different pic?
1976, stock bars
 
I mentioned somewhere that the biggest improvement I made was to run the clutch cable up the frame and exit between the forks above the bottom triple tree and below the headlight. The cable then makes a nice gentle sweeping curve back to the clutch perch. It may not look as pretty as the Yamaha diagram shows but makes the clutch easy to pull in. That was with the original Yamaha cable. I did the same to the XV and that too is easier to pull in.

I also found the single aluminium clutch rod gave more clutch control whereas the two piece gave more of an on off action.

I wonder, did 2M's all aluminum(6065T6) clutch rod pass the test of time?
 
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