InvisiBill
July 26th, 2020, 03:33 PM
After about 3,000mi of what I would generally consider fairly easy riding, my '18 started having the common clutch/shifting problems that have been showing up on the 400. Others have seen it after only a few hundred miles, so I think that attests to my "fairly easy" comment (and/or I just happened to get one with slightly better tolerances).
I really like this bike (it feels a lot like my 500, after I had spent considerable time and money fixing and tweaking things on it) and plan to keep it a while, so I figured it was worth it to get the "deluxe" package. I bought the whole Race Spec Clutch Upgrade Kit (https://www.norton-motorsports.com/product/barnett-heavy-duty-clutch-springs-kawasaki-ninja-400/) package, other than replacement friction plates.
Last week I did a quick fix and installed the updated pull rod/bearing (https://www.norton-motorsports.com/product/oem-2020-kawasaki-clutch-pull-rod-and-bearing-update-kawasaki-ninja-400-z400/) and the heavier Barnett clutch springs (https://www.norton-motorsports.com/product/barnett-heavy-duty-clutch-spring-kit-kawasaki-ninja-400/). These "beginner" bikes tend to come with soft springs to make for an easy clutch pull, which leads to almost no feeling in the lever, and in this case even seems to interfere with the clutch fully returning. The springs didn't feel much stiffer in my hand, but I'll take their word that they are, and the clutch does seem to feel a little better now.
However, the rod/bearing was a bigger improvement, I believe. Jesse's got all the details in that blog post, but basically the dimensions of the '18/'19 parts cause the clutch hardware to bottom out before all the friction material is used up. It seemed to slowly creep up on me - I didn't really feel like it was a problem until I fixed it and felt the difference. It's not a magical upgrade or anything, but the clutch now grabs like when the bike was brand new. I think I'd been subconsciously easing up on it due to small amounts of slipping. After installing the new parts, it just felt more solid and I noticed I was hanging out in the higher RPMs more too.
Yesterday I installed the other parts. I tore into it and replaced the shift detent spring (https://www.norton-motorsports.com/product/heavy-duty-shift-detent-spring-kawasaki-ninja-400/), shift star (https://www.norton-motorsports.com/product/ninja400r-race-spec-shift-star-kawasaki-ninja-400/), and shift change shaft (https://www.norton-motorsports.com/product/ninja400r-blueprinted-shift-change-shaft-kawasaki-ninja-400/). I can't really say that one part helped more or less than the others due to changing all of them at once, and they all work together anyway.
Detent springs are a pretty common upgrade. They put more pressure on the detent arm to make it go into the detents on the shift star more affirmatively. Nothing really special here. The new shift star is machined down to have sharper points and deeper detents. This makes it easier for the detent arm to fall in place for each gear. The shift change shaft is just a tighter-spec version of the stock piece. The stocker allows a lot of play (he has a video of just how sloppy it can get), possibly to the point of not properly engaging if your bike happens to have bad luck in the tolerances lottery and then a little wear. The upgraded part simply stays exactly where it's supposed to. It also comes with a delrin spacer to take up the slack between the shift knuckle and the engine. If you have a left side tipover, it will prevent the shift knuckle from trying to push the shaft out the other side of the engine.
I got to take the bike out for a pretty long ride today. The shifting just feels more precise. Shifting with the stock parts was more like ker-chunk, while the upgraded parts go ca-click. It just seems to more easily go to the next gear, without having to be so deliberate about it. All my shifts were perfect today, though I've only had a couple problems with the stock parts in several thousand miles. I can see the stock setup being a little more noob-friendly, but as someone with plenty of shifting experience, the upgraded parts feel much nicer
I did leave off the clutch cable spring (https://www.norton-motorsports.com/product/ninja400r-clutch-cable-spring-kit-ninja-400-2018-19/). It feels like a bit of a bandaid to me, mostly affecting lever feel. It can help return the clutch arm with the weak stock springs, but the HD clutch springs should take care of that now. It's easy to throw on later if I change my mind, but it would be more important on a stock bike.
The hardest part for me was actually getting the detent spring/arm installed. Their instructions say to install it first with the back of the spring off the boss, then hook it over with pliers. I had better luck keeping the spring on the boss as I tightened the mounting screw, and pushing the bearing end of the arm up onto the star as I went (using the arm's leverage against the spring). As you're fiddling with it, the bushing/spacer likes to fall off and into the oil pan too.
• I would suggest that everyone with an '18/'19 model replace the pull rod and bearing with the '20 parts (46102-0648 and 92045-0937). They're standard Kaw parts that drop in and will allow you to get full use out of your clutch plates. Jesse seems to be charging standard internet prices for them, so you might as well get them from him if you're getting anything else, but you should be able to get them reasonably from other parts places too.
• I would suggest that just about everyone replace the clutch springs too (Barnett 501-58-03121). You have to take them off to get to the pull rod/bearing anyway. Unless you absolutely can't handle any stronger lever pull, the upgraded springs will help the clutch hold better, at the cost of a tiny bit of extra effort needed on the lever.
• If you experience any problems with changing gears, I'd recommend upgrading the other parts mentioned. They're more money and more work to install, but they finish fixing what is probably the weakest area of this bike. If you're not having problems, I don't think there's a big rush to upgrade these, but they definitely are an upgrade and fix issues that a number of people have run into.
I really like this bike (it feels a lot like my 500, after I had spent considerable time and money fixing and tweaking things on it) and plan to keep it a while, so I figured it was worth it to get the "deluxe" package. I bought the whole Race Spec Clutch Upgrade Kit (https://www.norton-motorsports.com/product/barnett-heavy-duty-clutch-springs-kawasaki-ninja-400/) package, other than replacement friction plates.
Last week I did a quick fix and installed the updated pull rod/bearing (https://www.norton-motorsports.com/product/oem-2020-kawasaki-clutch-pull-rod-and-bearing-update-kawasaki-ninja-400-z400/) and the heavier Barnett clutch springs (https://www.norton-motorsports.com/product/barnett-heavy-duty-clutch-spring-kit-kawasaki-ninja-400/). These "beginner" bikes tend to come with soft springs to make for an easy clutch pull, which leads to almost no feeling in the lever, and in this case even seems to interfere with the clutch fully returning. The springs didn't feel much stiffer in my hand, but I'll take their word that they are, and the clutch does seem to feel a little better now.
However, the rod/bearing was a bigger improvement, I believe. Jesse's got all the details in that blog post, but basically the dimensions of the '18/'19 parts cause the clutch hardware to bottom out before all the friction material is used up. It seemed to slowly creep up on me - I didn't really feel like it was a problem until I fixed it and felt the difference. It's not a magical upgrade or anything, but the clutch now grabs like when the bike was brand new. I think I'd been subconsciously easing up on it due to small amounts of slipping. After installing the new parts, it just felt more solid and I noticed I was hanging out in the higher RPMs more too.
Yesterday I installed the other parts. I tore into it and replaced the shift detent spring (https://www.norton-motorsports.com/product/heavy-duty-shift-detent-spring-kawasaki-ninja-400/), shift star (https://www.norton-motorsports.com/product/ninja400r-race-spec-shift-star-kawasaki-ninja-400/), and shift change shaft (https://www.norton-motorsports.com/product/ninja400r-blueprinted-shift-change-shaft-kawasaki-ninja-400/). I can't really say that one part helped more or less than the others due to changing all of them at once, and they all work together anyway.
Detent springs are a pretty common upgrade. They put more pressure on the detent arm to make it go into the detents on the shift star more affirmatively. Nothing really special here. The new shift star is machined down to have sharper points and deeper detents. This makes it easier for the detent arm to fall in place for each gear. The shift change shaft is just a tighter-spec version of the stock piece. The stocker allows a lot of play (he has a video of just how sloppy it can get), possibly to the point of not properly engaging if your bike happens to have bad luck in the tolerances lottery and then a little wear. The upgraded part simply stays exactly where it's supposed to. It also comes with a delrin spacer to take up the slack between the shift knuckle and the engine. If you have a left side tipover, it will prevent the shift knuckle from trying to push the shaft out the other side of the engine.
I got to take the bike out for a pretty long ride today. The shifting just feels more precise. Shifting with the stock parts was more like ker-chunk, while the upgraded parts go ca-click. It just seems to more easily go to the next gear, without having to be so deliberate about it. All my shifts were perfect today, though I've only had a couple problems with the stock parts in several thousand miles. I can see the stock setup being a little more noob-friendly, but as someone with plenty of shifting experience, the upgraded parts feel much nicer
I did leave off the clutch cable spring (https://www.norton-motorsports.com/product/ninja400r-clutch-cable-spring-kit-ninja-400-2018-19/). It feels like a bit of a bandaid to me, mostly affecting lever feel. It can help return the clutch arm with the weak stock springs, but the HD clutch springs should take care of that now. It's easy to throw on later if I change my mind, but it would be more important on a stock bike.
The hardest part for me was actually getting the detent spring/arm installed. Their instructions say to install it first with the back of the spring off the boss, then hook it over with pliers. I had better luck keeping the spring on the boss as I tightened the mounting screw, and pushing the bearing end of the arm up onto the star as I went (using the arm's leverage against the spring). As you're fiddling with it, the bushing/spacer likes to fall off and into the oil pan too.
• I would suggest that everyone with an '18/'19 model replace the pull rod and bearing with the '20 parts (46102-0648 and 92045-0937). They're standard Kaw parts that drop in and will allow you to get full use out of your clutch plates. Jesse seems to be charging standard internet prices for them, so you might as well get them from him if you're getting anything else, but you should be able to get them reasonably from other parts places too.
• I would suggest that just about everyone replace the clutch springs too (Barnett 501-58-03121). You have to take them off to get to the pull rod/bearing anyway. Unless you absolutely can't handle any stronger lever pull, the upgraded springs will help the clutch hold better, at the cost of a tiny bit of extra effort needed on the lever.
• If you experience any problems with changing gears, I'd recommend upgrading the other parts mentioned. They're more money and more work to install, but they finish fixing what is probably the weakest area of this bike. If you're not having problems, I don't think there's a big rush to upgrade these, but they definitely are an upgrade and fix issues that a number of people have run into.