Blake's 1979 XS400 Build

[blakeloydmaloney]

Finally picked up a solid base for a bike! So pumped to finally be a part of the xs400 crew!

A little background. Picked up this bike for a grand. It has just over 12k miles on it, the carbs were just rebuilt and rejetted since I live up in the Rockies (Colorado Springs, CO). The PO also replaced the spark plugs and wires, installed an inline fuel filter to keep the carbs clean for a while, cleaned and sealed the tank, and adjusted the valves and timing. The price was a bit steep, but I was willing to go for it since I know the guy that did all the engine work and would rather work more on the build than getting the engine to turn over.

I am leaning toward a tracker/brat style bike and once the winter ends it will most likely be my daily driver. If you guys have any tips or things I should take a look at right away let me know! I have helped buddies build bikes before, but this is my first solid project/rebuild.

I am going to start with flushing and rebuilding both brakes, getting stainless steel lines, replacing the fork springs with progressive springs, and getting a seat built first. I will keep it updated with pics!

 

[blakeloydmaloney]

Today I got the front forks off and dismantled them for a rebuild. Even though the engine runs well it isn't really safe enough to drive. The fork seals are leaking a ton and the fork oil seems to be the original from the 70's. Luckily the bike was garaged by the PO, so there is no pitting at all on the fork tubes. I couldn't believe it.

The seals were insane to get off. I used different lubricants, heat, pry bar, etc. I took a couple hours of work and some bruised hands, but I finally took care of it. I am planning on painting my fork lowers black, so I have some sanding prep to do.

I have a question for people with a bit more experience with bike performance than I have.

If the bike has 12k miles is it safe to say that I need new fork springs, or would I be ok to change the seals and put in heavier fork oil and put it all back together?

I do want to switch to progressive springs, but if I can save the $80 now and put it toward something else I can keep going on the project.

Also, the PO said he had some issues with it stalling after a few miles and assumed the issue was that the gas cap wasn't venting. I would drive it until it would stall and would pop the cap open and it would run well again for a few minutes. It did it over and over, so I assume that the gas cap was the issue. I know the vacuum lines are pretty suspect on older bikes, but the lines were just replaced and everything seemed solid. You can see how bad the gas cap was in the pics.

Another question: Is there any type of o-ring that will work in place of the cracked cap gasket? There are replacement ones online, but I feel like I could get away with something cheaper than $20.

I have a lot more pictures that I will post soon. Thank you guys for all your help!

 

[blakeloydmaloney]

Forgot the pics. My bad.

 

[xschris]

I would replace the seals in the forks and use the oem 20w fork oil in them as the manual calls for. You can measure the spring length to see if they are still in spec. My guess is they are, my 79 with 34k miles are still in spec. The gas cap uses a seal not a o-ring. Replace it with a new one $20 is not a lot to keep gas from spilling all over a hot motor.

 

[Wolfe_11B]

The seal is like $8 from MikesXS. Pretty good price for preventing what Chris mentioned above.

 

[lemonhead]

Your gas cap looks just like mine and I have no problems. Sometimes you get a little funk stuck in the tiny breather hole in the center of the cap that prevents venting. I've cleaned them out on other machines with a little compressed air and a wire.

 

[blakeloydmaloney]

Well, I got the gas cap all worked out and ordered a seal for cheap off of MikesXS. I decided to pass up the progressive springs for now and am rebuilding the forks with new seals and replacing the oil.

I didn't get to do a ton on the bike because we spent the week below 20 degrees and got about eight inches of snow, but I did get a boxier style gas tank off of a 77 xs400. It has a bit of rust, but I have dealt with it before so I am okay with that. The paint is actually in better condition than the original tank in my previous pictures and I was able to pick it up for $50, which I know is a steal for that style of tank. It even has the key! That made my week to be honest.

I also got a lot of the cosmetic stuff removed so that I can simplify it. No more turn signals, no more big tail light, no more tall mirrors. I am cutting the stock fenders down and browsing through some other builds to find out how I want them to look.

I will have some more pics up later. Now that there is snow I will probably be taking things one at a time since the work area in my basement is tiny.

 

[blakeloydmaloney]

Today I finally finished my fork maintenance and installation. It was all pretty straight forward thanks to all of the people who have given tutorials on this site. I took them apart, cleaned them well, got them painted, and rebuilt them with new seals, 20W fork oil, and mikesxs gaiters since the original boots were cracked. My springs measured to be in spec, so since the install was pretty quick I decided to pass up the progressive springs for now. If I really think it is worth it later I may give them a try.

A lot of guys have wondered about painting fork lowers and if the paint sticks well or not. I would say that it is about 90% prep and 15% painting. I stripped the old clear coat, sanded them down, used two coats of aluminum primer, 3 coats of paint, and two coats of an automotive gloss clearcoat. I was pretty rough on them putting them back into place and have no chips on them yet. I guess we will see after a few hundred miles.

I have a couple pics of the forks once they were done and after they were installed, as well as a picture of all of the things I used for the paint job.

I just ordered a master cylinder rebuild kit and stainless steel brake lines for the front and back brakes, so I will post some pics once I get to rebuilding them. Now I just need new rear suspension, tires, and a seat before I can at least take it around the neighborhood safely.

 

[blakeloydmaloney]

So... I thought I was going to put it away for the winter and not ride it, but I couldn't resist. It has been an abnormally warm and dry winter here in Colorado, so I got out with about 8 other guys for a nice 50 mile ride around the Garden of the Gods, Manitou Springs, and other nice roads around Colorado Springs. It was super nice to get out and see how it handled since I had only ridden about three miles before I started wrenching.

It isn't much to look at yet, but it runs beautifully. The fork rebuild did wonders, and bleeding the brakes before the ride made a huge improvement. I never had a hiccup, which makes me glad that I don't have to worry about getting it to run well, just perform better.

I spent a lot of time reading over Christmas break about building a great bike that performs well. Luckily I haven't started much yet because I want to switch directions with my ideas. Instead of focusing my build on having a certain look I want to build it to perform well. There are plenty of builds around town that have firestone champions, cheap clip ons, chopped mufflers, no fenders, run rich and cut out from shoddy electrical work. (No offense at all if this is your style. They look cool. I am just looking at something practical that performs safely, handles well, and keeps my engine and face free from the mud.)

Over the next bit I want to focus on a few things. I need a new headlight and brake light (a buddy accidentally broke my headlight bucket and my Amazon tail light stopped working after one long ride [buy quality]). I am going to fix the rear end of the frame so I can build my seat (I'm going for the look of Ginger McCabe's xs400 rear end). I am in the process of building a rear fender that actually mounts well out of an old GS750 rear fender. Before I go on my next ride I need new tires (either Dunlop K70 or Shinko 244 since I ride quite a bit on dirt). I am going to go close to stock size with a 3.5x18 rear and 3.0x18 front tire. Once I get all of that out of the way I will have a solid, daily rider bike that I can make small improvements on over time.

A few things: Does anyone have suggestions about the choice of tire? They last a while, so I would like to get something decent. I know Dunlop tires are awesome, but I don't know about Shinko.

Has anyone heard about making a hoop from old handlebars? I have a couple sets and it seems like a decent way to go. I tried searching in the forums and heard of people doing it, but didn't see any write ups.

Last but not least, here are a couple pics of how the bike stands now, my new Biltwell I got for Christmas, and a group shot of the ride.

 

[rshutchinson]

I got a set of Avon Roadriders for my wifes XS and they're great and have a nice sporty tread design. They are a little narrow though I found so you may want to go up one size on them compared to other tires.

 

[JimVonBaden]

Looks pretty good. I did this with my tail light:

My fender is similar, but I wanted the plate to be legal, and turn signals.

 

[blakeloydmaloney]

Finally got my new tires in! Now, to get them on...



I went with 3.5x18 for the front and back. I went back and forth because I know 3.0x18 is a closer match for the front, but the knobby tires I wanted were only rated for 70 something mph if I stayed with the 3.0. I have ridden and will ride that speed pretty often, so I went up in size and will be good to 100 mph if I ever need.

I'm hoping the front fender will still be able to fit. The different posts I read had different answers, so once the 22" of snow we got this week starts to melt off I will see what I'm working with.

 

[blakeloydmaloney]

Im having a hard time I bedding the pictures. Sorry.

 

[blakeloydmaloney]

Got my tires mounted and installed today and went on a nice fifty mile ride to break them in since its abnormally in the sixties in February. The only bummer is that the stock front fender won't fit over the new tire without a bit if trimming first. Other than that, everything was pretty straight forward. My speedometer cable rubbed a bit, so it ate through part of the rubber before I got the zip tie on as a temporary fix. I will end up replacing it asap.

 

[Herd]

Nice! Like the tread. It's a good look.