Yamaha XS400: Brake and Clutch upgrade

[@alexblackburn627]

My 81 xs400 special ii has front and rear drum brakes and I love the look of them!

[@peterbell9683]

Greetings! I'm rebuilding the front brake caliper on my 1983 xs400 w/ only 2,200 miles on it (I have 4 others that see more miles). The rebuild kit worked fine, I've cleaned up the piston, reassembled, all good. But, brake is not pumping up. Master Cylinder at the reservoir? It isn't feeding brake fluid down to the caliper... blocked or is there some kind of secret to this bike? I've never experienced this w/ either of my Honda's or for that matter, any of my cars. Thanks! ps. love the videos!

[@aztriumphster]

Hey Peter. When I added a second caliper to my XS 500 I felt like it took a lifetime to get pressure again. Turns out there's alot of air in a caliper so I had to improvise, otherwise ide have aged a couple years before getting pressure again. I picked up a large syringe and flexible tubing from a feed store. I sucked some brake fluid into the syringe with the hose and attached the other end of the hose to the caliper bleeder screw making sure there was no air in the hose or syringe. Cracked the bleeder screw and slowly forced fluid into the caliper. This will also force air upward toward the master so after a few times of doing this, u should be start to feel pressure. Once u have disconnected everything, pump up what pressure u do have then squeeze the caliper against the disc forcing the piston to push fluid and any air upward. Do that a few times and u should be golden.

[@peterbell9683]

@@aztriumphster Thanks AZ! What a quick reply! And, because some of these posts are a few years old and apparently unattended, in the interim I called a buddy whose just restored a couple of Honda CBX's and he asked if I'd "benched bled the master cylinder" a phrase I've never heard and indeed, he agreed was counter intuitive as, after all, if ya take the damn thing off, how are you keeping air out during the reinstall? And, in all my years, I've never bled a master cylinder. Noting that Brembo equipped bikes do have a bleeder valve at the master cylinder but the xs400 does not, I loosened the main line at the master cylinder and bled there as I would've at the caliper. Got pressure! With that I did the caliper next and we're good to go. I'm going to guess you overlooked mentioning that lil idea as perhaps most every beanhead knows to try bleeding at the master cylinder... but this one didn't! :) But thank you.. I'm a subscriber! Have a great Sunday, peter

[@davidlvann]

Make sure you put those OEM parts on ebay! My bone stock XS 400 braking system works great. Original everything including seals and hoses (but not fluid). Still on factory brake pads.

[@GIMLEGAMING1994]

Where do I get parts for my xs400, I really want to rebuild it but can't seem to find any place where they have good parts 😕

[@WhereAreMyUndies]

I need to do this exact job on my 79 xs400. I love the look of what you used here. Can you provide a link to the master cylinder and levers you used?

[@aztriumphster]

The master cylinder and clutch perch were used, purchased on eBay. They were off a Yamaha fz/mt 07 or 09. The levers were just cheap Amazon ones for an fz/mt 07 or 09

[@peterbell9683]

AZ... so everything went great, test ride was going well until.... something started really slowing the bike down... just one mile from home! Damn, the front brake was locking up! And smoking like an F1 brake! I kept playing w/ the brake lever, hoping to generate some relief and... enough to slowly motor the 1 mile home... at about 10mph. I poured some water on it to cool things down but left it parked for the evening. Obviously, I have to take it back apart to see what "could possibly have gone wrong" but... any thoughts? When that happens do I automatically need a new replacement seal kit? Was there still some air in the line that might've caused the piston to seize? Not my first rebuild but on the other hand, don't profess to be an expert. Thanks!

[@aztriumphster]

Peter I have only encountered that once with the rear brake on a 2014 Sportster 883. I believe I may have caused it by dialing out too much freeway in the lever and linkage. I added about a quarter turn to give some slack back and it never did it again. I am not certain that is your issue here. Possibly the piston got stuck applying pressure on the pads, but I dont think air in the line would do that. Did u install new pads along with the new caliper?

[@peterbell9683]

@@aztriumphster I did not change pads as these have just 2,300 miles on em and look great. I'll break it down later this week... wondering if I ruined the new rubber O rings... things were smoking!

[@aztriumphster]

@@peterbell9683 if not a stuck piston then maybe the pads got hung up at one of their contact points. I haven't had an issue with pads on a bike but I did have to go thru and grease all the pads tabs, where they are supposed to move freely on their respective hangers, on my car. Never really knew what that little tube of grease was for when I bought new pads until I looked into it to do the work on the car.

[@peterbell9683]

@@aztriumphster Good point... I did use their lube on the replacement seals but maybe the pads caused the problem... thanks again and stay tuned!

[@peterbell9683]

Ok... a good friend whose just restored his second Honda CB1000C exclaimed "I'm 99.9% sure that the inner hose has collapsed and not allowing the fluid to retract and consequently, the piston will not retract either." He further directed to expect, with things cooled, that everythings retracted, pump the brakes, loosen the bleeder... if it spurts out, it's indeed the brake hose retaining the fluid. I followed those instructions and that's what happened! So I'm in process of ordering a new hose. It's news to me! But it's what just happened to him on one of the Hondas. Who knew?

[@God-Undefeated]

Hey I’m looking for a set of carbs for a 81 xs 400 special any info would help great bike

[@andybombs1143]

nice video i recently just purchased my first bike and its a 79 xs400 but the clutch is slipping in the high rpms any help would be appreciated!!

[@aztriumphster]

Congrats on your new bike acquisition. First, check that your clutch cable has the appropriate amount of freeplay. If so, then if you haven't already, I recommend doing an oil change. Try running 20w50, non synthetic. See if that helps with the slipping. If not, you will probably have to get into the clutch basket. Luckily, clutch/friction plates aren't expensive, and if it fits your budget, you could upgrade three springs, hardware, and cable.

[@lukaskybartas]

Nice video. Thinking of getting XS400 for my first bike. How much kw does it have? Searched the internet and found few different variants... Is it possible for 1982 to have 34kw?

[@aztriumphster]

Great first bike if u r wanting to learn how to work on them and maintain them while u grow ur riding experience. Making power on older bikes isn't like it is on these new modern bikes. If you are wanting a simple motor design with more power capability, you may want to look at the XS650.

[@lukaskybartas]

@@aztriumphster Thanks! The question was if it was possible to be 34kw stock. Just seen the documents, appearently it’s 20kw. So I assume bike parts shop made a mistake in listings. Pity it didn’t start as battery was almost dead. Kickstarter went without any back force (sorry for the english) and there was leakage of oil i guess on the side stand….

[@xxgodofcornxx8911]

I just bought a 81 xs and it needs a front caliper mine broke at the mount any idea where to get a new one?

[@aztriumphster]

Have u checked out Mikes XS?

[@xxgodofcornxx8911]

@@aztriumphster yes he has everything but calipers I've spent like the last 2 hours looking online and can't find jack.

[@aztriumphster]

www.cmsnl.com/yamaha-xs400s-1981-usa_model8826/partslist/E-01.html#.YKMuiWllCdM

[@xxgodofcornxx8911]

@@aztriumphster yea I saw that one unfortunately its out of stock. I appreciate the help though.

[@aztriumphster]

@@xxgodofcornxx8911 if u want u can email me some pictures of ur current setup and I can take a look I've had an 81 xs650 and 77 xs500 as well

[@bradb.4570]

Ride safe everybody! I got into a decent crash yesterday. Please, please, please wear your helmets even if it’s not illegal to not wear one. That either saved my life or my injury’s could have Ben ALOT worse. Ride safe guys

[@aztriumphster]

Wishing you a speedy recovery

[@ingridmoran]

Any advice for replacing a clutch cable on these?

[@aztriumphster]

The perch side is straightfoward because its like most other Japanese bikes. The motor side is a bit more complex because the cable passes through the engine cover. So u first need to loosen the worm gear to take tension off the cable, then remove the engine cover, then disconnect the cable from the worm gear. Next feed the new cable.intonthe cover and connect it to the worm gear then re install the cover. Check factory recommendation for the worm gear setting and go ahead and dial that in then make any fine tuned adjustments at the perch.

[@SolidGRND]

do you have a video adjusting the clutch from the case? i got no play in xs400 i wanted to add some back lol

[@aztriumphster]

I dont have a video, and I dont think I'll have the xs400 comin thru my garage soon enough to get u what u need quick. I can certainly try to walk u thru it on here messaging. Lemme know

[@SolidGRND]

@@aztriumphster thanks man sorry for the late response. I'm going to replace the cable all together but do I need to drop the oil? The clutch cable goes into a cover that looks separate from the clutch disc housing cover. so can I just take it off or is oil in there?

[@aztriumphster]

@@SolidGRND the left cover, that the clutch cable leads into, can come off without losing any oil. The cable will have to be disconnected from the worm gear in order to take it off the bike completely.

[@aztriumphster]

@@SolidGRND before u replace the cable try this: loosen the friction on the clutch lever all the way so there no tension there. There's a quarter size cover on the left case cover that when removed, grants access to the worm gear adjuster. If u pull that tiny cover u will see a philips head screw inside a hex nut. If u break the hex nut loose, u can then use the philips screw to adjust ur friction zone. Use it for the big adjustments and the clutch lever adjuster for small adjustments.

[@aztriumphster]

@@SolidGRND tighten the philips screw till u feel some resistance then back it out a quarter to a half turn, this will set ur friction zone with range to make any additional adjustments at the lever. Tighten the nut around the philips screw and replace the cover and u r good to make ur adjustments at the lever

[@84cleancut]

Why happened to the beard bro ?

[@aztriumphster]

Eh, got bored. It'll be back.