1981 Yamaha XS400 Scramblerized...

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1981 Yamaha XS400 Scramblerized...

Postby JimVonBaden » Tue Sep 08, 2015 7:41 pm

I picked this up from an inmate the other day:




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For him it was a bobber project:




from this:

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To this:

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He started out chopping the rear and relocating the shocks, then adding a seat pan, plus a bunch of work.

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(photos courtesy of his photobucket account, and mine)




My plan is to beef up the suspension, beef up the shock mounts (they are fine for street, but I am big and need them really strong), redo the wheels (but keep the drum brakes) and generally make it look period, but very clean and newish looking. I even hope to fab a set of high pipes for it.




Just a first look:

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Note the modern 2015 R1200GS seat foam and cover I hope to add. I plan on changing the tank to something smaller.




I want pipes similar to this:

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and paint like this except Yamaha yellow:

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The overall look will be similar, but a lot less chrome.




I warn, it will not be a fast project, but I will eventually get it done.




By the way, any suggestions for Scrambler type tires to fit

R 90/16 4.5" wide 120/90/16

Fr 350/18 3.75" wide, 80/100/18



Preferably matching.

Jim :cool:
Last edited by JimVonBaden on Sun Sep 20, 2015 9:43 pm, edited 1 time in total.
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Re: 1981 Yamaha XS400 Scramblerided...

Postby Rick F. » Wed Sep 09, 2015 5:59 pm

Jim,

Looks like a fun project! With the exhaust pipes the way they are now, it looks like a dirt-track racer.

For some reason, I've never been able to shake my desire for one of the classic mid-1960s Yamaha 250 street bikes. It's undoubtedly because I wanted one during my first motorcycle phase, in college, but I couldn't afford one back then. Now you can't even find one!

Good luck with your scrambler,

Rick
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Re: 1981 Yamaha XS400 Scramblerided...

Postby JimVonBaden » Thu Sep 10, 2015 2:28 pm

Thanks Rick!

I have several parts on order and am waiting for cooler weather to get started. I want to test the motor before I get too far into it.

Jim :cool:
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Re: 1981 Yamaha XS400 Scramblerided...

Postby Chiba » Thu Sep 10, 2015 3:28 pm

Didn't your trailer used to be orange??
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Re: 1981 Yamaha XS400 Scramblerided...

Postby JimVonBaden » Thu Sep 10, 2015 11:28 pm

T.Wesley wrote:Didn't your trailer used to be orange??

More like faded from red to pink. I did a major overhaul last year.

Jim :cool:
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Re: 1981 Yamaha XS400 Scramblerided...

Postby JimVonBaden » Thu Sep 17, 2015 8:12 am

At this point.

I ordered a pipe build kit, since I can't really bend my own. I also ordered a new tank, cap, valve, filter, hose, spark plug caps, battery, Speedo/odo/indicator gage. They should be in within a week.

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My plan is to get it started and see if it is mechanically sound, then fab all the pieces and get them fit up. once I have what I want, I will strip it to nothing but pieces and start the powder coat, paint and polish. Lots of steps in between to post about.

Jim :cool:
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Re: 1981 Yamaha XS400 Scramblerided...

Postby JimVonBaden » Thu Sep 17, 2015 10:16 pm

Got in the parts. I am a bit conflicted on the tank, but I think it might work aesthetically.

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Sitting on the bike:
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I also got in the pipe kit. I think I can make it work.

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I'll get started on the weekend, but I am quite excited to get going.

Jim :cool:
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Re: 1981 Yamaha XS400 Scramblerided...

Postby Rick F. » Fri Sep 18, 2015 5:58 pm

Jim,

Your project continues to look like a lot of fun, and, of course, it's always great to have NEW PARTS arrive!

I'm still trying to figure out the pipe kit. When I visualize the connections, the exhaust seems to exit forwards. It's possible that I'm doing something wrong… :D

Do you know when it last ran? I was wondering whether a carb rebuild might be needed.

Good luck and have fun!

Rick
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Re: 1981 Yamaha XS400 Scramblerided...

Postby JimVonBaden » Fri Sep 18, 2015 6:47 pm

Rick F. wrote:Jim,

Your project continues to look like a lot of fun, and, of course, it's always great to have NEW PARTS arrive!

I'm still trying to figure out the pipe kit. When I visualize the connections, the exhaust seems to exit forwards. It's possible that I'm doing something wrong… :D

Do you know when it last ran? I was wondering whether a carb rebuild might be needed.

Good luck and have fun!

Rick

Hi Rick,

I am finally at a point where I can try to start it, this weekend I hope. We will see then.

The pipe kit just gives me bends. I will have to cut the pipes at exactly the right points and then weld them together to get the desired shapes. Hopefully it will come out like this, or close:

[img][/http://i20.photobucket.com/albums/b238/JimVonBaden2000/JVB%20Productions/XS-400/pubadybu.jpgimg]

I will be coating it, not chroming it though.

Jim :cool:
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Re: 1981 Yamaha XS400 Scramblerized...

Postby JimVonBaden » Sun Sep 20, 2015 9:55 pm

Had some free time to work on the XS Scrambler today.

First I hooked up a battery and used a little starter fluid and it cranked right up. It ran fine, so I shut it down and proceeded to mod it.

First on the agenda, since I wanted to make sure I could actually do it, was the exhaust.

It started like this:

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I used this kit for custom exhaust:\

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Then proceeded to cut and grind to fit the pieces up and make the whole.

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Once positioned and tack welded, I took it apart and welded the rest. Not a great job, but it looks pretty good to me. The flapper wheel is the crappy welder's best friend.

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Not even close to perfect, but I am happy with it.

In the end, I hope to make it good enough to ceramicote, or at lest high heat paint.

More to come!

Jim :cool:
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Re: 1981 Yamaha XS400 Scramblerized...

Postby Rick F. » Mon Sep 21, 2015 3:42 pm

Jim,

Okay, now I understand the kit! Great job on the scrambler pipes and mufflers--I'm very impressed!

Rick
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Re: 1981 Yamaha XS400 Scramblerized...

Postby JimVonBaden » Mon Sep 21, 2015 7:32 pm

Rick F. wrote:Jim,

Okay, now I understand the kit! Great job on the scrambler pipes and mufflers--I'm very impressed!

Rick

Thanks Rick!

It looks better because of the magic of a good grinder and the flapper wheel discs. My welding is never pretty!

Jim :cool:
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Re: 1981 Yamaha XS400 Scramblerized...

Postby VANikonShooter » Thu Sep 24, 2015 3:32 pm

Dayum!

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Re: 1981 Yamaha XS400 Scramblerized...

Postby JimVonBaden » Thu Sep 24, 2015 10:17 pm

A little more progress today. Took about three hours to remedy a deficiency in the mods done by the last owner. The rear frame where the shocks mounted were basically U-brackets welded to the end of the frame tube. no reinforcing. Since I am a heavyweight and the bike will doubtless get some off pavement use, I needed to add some steel to the shock mounts.

Started like this:
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Note that the frame rails just ended, with little keeping them from spreading, and not very strong brackets to hold the shocks.

Made a paper template for each side:

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Found some 3/16 mild steel to make a cross brace:

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Used similar 3/16 mild steel for the frame braces.

Ready to weld:
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Tacked in place:
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I need to touch up my crappy welds, but this should be plenty strong now.

Jim :cool:
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Re: 1981 Yamaha XS400 Scramblerized...

Postby JimVonBaden » Sat Sep 26, 2015 6:58 pm

A bit more from yesterday:

I made a mount for the tank from found parts and tacked it into place.

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The welds are just tacks. I plan to weld fully, and fully clean the look when I strip the bike for paint.


Then made a bracket to attach the new gauge with lights.

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Measured up for shocks:
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I'm thinking 1-1.5" increase.

Just a couple more shots of the rear frame reinforcement:
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Next I need to notch the left frame to allow the tank petcock to fit. Then I want to revamp the rear fender, find a suitable front fender, create a bash plate and figure/make out the side covers.

Of course there is a new headlight, tail light signals, horn and rebuild the entire wire harness.

Oh, and clean everything, paint a cool tank and fenders, frame and check/repair the brakes and forks.

Not much at all, assuming the motor, clutch and charging system is sound.

Jim :cool:
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