Advice sought on how to get a clutch on XS400 like butter - smooth and delightful to use?

[Peter B]

The Clutch on my XS 400 (1981 SE now in cafe racer style) is very heavy to use - not really a big issue just a reality. I just thought well it is cable operated, wet plate and needs the engine oil to be hot etc just accept that is the way it is. However, having noted a few comments on the forum suggesting it could be otherwise I'd ask if someone has some hints and tips on how to make it buttery smooth and light that would be appreciated. Thank you in anticipation

 

[CaptChrome]

I don't know that the term "buttery smooth" is very accurate for a cable operated clutch. I always operate my clutch with two fingers and chalk that up to having a cable in good condition and lubricating the crap out of it with gear oil at the start of each and every season.

 

[nofun]

Why are we nitpicking the phrase "buttery smooth" — in my opinion, it is attainable, especially if you are dealing with a difficult and heavy-to-use clutch. For me, it was a case of "anything has got to be better than this," and what I achieved was, as I would put it, buttery smooth. Here is a checklist of steps I would take to solve the problem. Each one is a little more invasive and time-consuming, so I suggest going down the line and hopefully one of these solves it before you have to fully replace the clutch plates.

1. As Capt mentioned, lubing the cable is a straightforward step, I would start there. Also, check out your routing; if it isn't right for your length, it can bind and be a real pain to pull.
2. After lubing and checking your routing, you will want to crack the sprocket cover. You will need to pull your foot peg (if it's in stock position) and clutch pedal first to access it. There are six hex bolts to get in. Check what condition your clutch release is in, if it's shot or you feel you want a new one, Mikes XS has one you can toss in. Pay attention to orientation if you do replace it. Mine was broken, so I had to replace it, but what I learned was that mine was installed upside down at some point in its 40-year life, and I suspect that had a massive hand in the problem. The female end (the side that screws into the sprocket cover) needs the long end up and the short end down, or rather, the short end goes into the adjustment port and faces out when the plate is installed. Either way, new or not new, disassemble it and give it a solid cleaning. When you reinstall, you can apply both the male and female ends with a light coating of grease. I used Lucas Oil Red N Tacky Grease so they could slide a little easier when you pull the clutch.
3. While in there, pull your clutch push rod and check if it's level and true. If it's not, replace it. I picked one up on eBay for $7. I didn't need it in the end, but I am holding on to it because I have read they can get bent from time to time. The push rod simply pulls out; no screws or connections you need to worry about. While removed, grease this too. Apply a thin coat of grease on the entire push rod and put some on the end that passes through (not the sprocket side) — there is a tiny 5/16" ball bearing at that end that helps push the plates in. When you push the rod back in, the rubber gasket likely rubs some of it off. I removed mine, recoated it once more, and cleaned the excess after installing it (this step may be pointless, but I'm just sharing what I did).
4. After that, put the sprocket cover back on, tighten the hex bolts down, and test your clutch. If the sprocket cover isn't tightened fully, you can get false clutch feedback, as the clutch release spring won't have a solid resistance to actuate. You should notice a significant difference — at least, I hope you do.
5. If you are still experiencing some difficulty, you may want to replace your clutch plates. I won't go into depth on that as there are some great resources on YouTube that walk you through it. It's an easy job, just a bit messy. Think of it like an invasive oil change, ha!

I did these steps out of order. I jumped to #5 before I did #2 and #3, so I am hoping you have success before jumping there as well. I truly can't describe how difficult pulling my clutch was and how easy it is now. I thought how heavy it was was normal, especially reading everyone on here act like heavy is normal. But comparing it to my '78 CB200, which is 3 years older than my '81, which had as buttery of a clutch as my buddy's 2023 Royal Enfield, I knew there were greener pastures.

Welp, that's it — good luck!

 

[Peter B]

I'm tempted to buy a set of 4 new clutch springs as less than 10 bucks in total for the parts and I'm pulling the clutch to inspect it.

Has anyone swapped out the clutch springs on their 40 year old XS 400 and did it make it the lever lighter to use or heavier in the left hand?

 

[Peter B]

By way of an update. I bought new clutch springs from Yambits. Took the clutch plates apart and found some has some heavy dirt bits on the metal plates which sit between the friction plates. So they were subsequently easily cleaned carefully on a dead flat surface. Attempted to gauge spring tensions by feel of pressing them down on dead flat surface and concluded the new ones a bit springier but marginal difference. Refitted and all is well but still feels like a heavy cable operated clutch...which it is

 

[Ezetman]

would softer/stiff clutch springs help achieve a softer clutch pull?

 

[Peter B]

From my perspective the jury is still out. The new springs needed marginally less force to compress them on the bench and clutch operation appears to be improved but frankly it is still quite heavy. I suspect the benefits achieved from my interventions were gained from cleaning the dirt / surface rust off of the non friction clutch plates as opposed to swapping the springs. Sorry not to have a more definitive answer...

 

[avemachina]

I finally got my clutch adjusted properly (for my definition of "usable without noticing that I'm using it") and here's my insight: it's worth checking if your cable isn't bent, pinched, or binding anywhere, especially near the adjuster (not caught in the little split) by the lever or where it joins to the sprocket cover.

Lubing with gear oil helps significantly, as well as routing--I can't overstate how big a difference routing makes; you can wiggle the cable around while squeezing the lever to test out various positions of the cable. Even moving it 2 inches/5cm can make a difference in how the lever feels. I tried the routing diagram in the service manual and it still felt heavier than I liked, so I took a little bit of creative liberty to arrange it in a way that feels nice and keeps the cable away from friction/heat.