My SX650 Scratch Bobber build

BobbedSled

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My XS650 Scratch Bobber build

HI all, I'm new here. Figured I share XS my build. I always wanted to build a bike, don't really have a craving to ride one, it is is a bucket list thing as much as anything. "Build a motorcycle from scratch". Kids can ride it when I am gone. Figured I'd post it up so maybe someone else can get something from it. I will definitely need help when it comes motor break down and rebuild time. Maybe something here will help someone in the mean time. :)

I raced MX for years but street seems unsafe but I am still drawn to them. I love bikes in general but I am kinda anti Harley with all the branding and clothing that seems mandatory when you ride. Almost cult like. I mean that's fine if that's your thing, I just don't follow the pack that way. In fact I head the opposite way. SO I decided to build a metric type bike.

What I like is vintage cafe raceways and bobbers that are not all chromed and shiny with mega dollar paint jobs. More home garage type of thing less store bought type of thing. Something different of you follow what I mean.

After watching all those biker shows it did not seem that hard. Decided if I was going to build it that I would build it and not chop an existing frame. I suppose I will have problems with registration but I'll cross that bridge when I get there. Kept all receipts including those for the raw metal.

Started looking around, Meritc is the way for me, v-twins were OUT. Wound up opting to use XS650 engine based on all the aftermarket stuff. I wanted to build something a bit different but familiar. Kind of dragged/cafe/bobber type of sled. Sort of long but not 2005 absurd, sort of low but not too low, kind of old school but yet still contemporary looking.

Anyhow it makes sense in my head. :laugh:

So designed a frame in CAD that is based on sort of like an old school chopper type of rigid. I then made a frame jig for 1 time use, bought a tube bender, bought a notcher and Miller 211 and some new tools and compressor yada yada. Franky the tools will cost as much as the bike but we all loves our tools.

I have never worked with metal before this is my first time building anything so bear with me. I am sure veterans will find all sort of mistakes, but that is the point for me to learn.

So here we go, I am dying to see how it turns out myself. If nothing else I'll learn a lot. While it is not super easy it is way easier than I though it would be.

Here is the jig, does not look like much but it is square and is intended for 1 time use.
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First thing is bend some tubed for the rear wheel hoops. This type of design requires 1 bend per tube which makes it easy. I used 1.25" OD HREW tubing which was .120 wall. It requires one 90 degree bend. It takes like a 96 degree bend as the tube bounces back. Lots of trial and error there. I had to re-buy lots of tube, but it is pretty cheap.

I used Pro-Bender and their dies, made a rolling base for it and added harbor freight air over hydraulic ram. Works really really well.
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Here we go all 4 done, put a 1" tubing slug in the end
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Lay it in a jig and clamp the ever loving crap out of it for welding.
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Reverse it in the jig so it sticks out so I can finish welding the other side that was facing down in the jig for initial alignment.
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Start sanding with angle grinder and flap wheel.,
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When done it looks like 1 piece of tube.
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Now add some end caps, Clamp and weld Mig them, looks matter not here it gets all ground off.
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Then sand them down, this is before final sanding but you can see it gets smoothed out pretty good.
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By the way check out that band saw in the pic above. It is just a Milwaukee hand held deep cut band-saw. Swag offroad sells a table that the hand held unit mounts to. Super simple and super small form factor and super effective for what I need.

Got axle plates cur by local water jet shop
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Mark for cuts and then cut
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Walla done, now just duplicate the other half.
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Next I needed wish bones to connect the top hoop to the back bone.
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Here is a test notch in the jig to verify notch angle prior to bending the tubes. I am using the JD2 Notcher that I clamp into a vise.
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Bend them then square them together and mark them for cutting, Had to buy a chop saw too, most of the cutting was done with a chop saw.
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Then notch them according the the angle desired that I verified previously with a test notch shows up above.
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Clamp in the axle plates and tack em up
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Then I take the same jig I used to bend the wheel hoops and I have a section for the wish bones. I mount it to the wheel hoop and clamp in the wish bones.
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I then added a tab for the head tube and cut the back bone once I checked for clearance. Whew, seems to fit. The motor is a 1971 model that supposedly runs, got it on eBay, it had 34K miles on it. I plan on rebuilding it.
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Now it was time to start the engine cradle, and her they are done.
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Now I need to notch the cradle tubes. Lots and lots of test notches were done. Here is a test notch for example
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Once you get it right it looks like this. I got the head tube from BEOCS on ebay. Actually I got the end caps and some other stuff from them too.
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Make some, motor mounts, I actually wound up cutting these off and having to make another set. If you do this, use a grade 8 bolt for the lower engine bone to tacking the mounts. I used a threaded rod at first and the rod bowed and bent. After removing the engine an actual grade 8 bolt did not go through it, the mounts were not aligned not were they level due the the threaded rod flex which was substantial. Anyhow I made a newer better set, here is the first set.
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I mocked up boxing the head tube and cross brace tube while I was at it.
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Here is is with the second set of lower mounts with the front mount in place as well. Notice the finished boxed the head tube and added a cross bar between the top tube and the engine cradle tubes.
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Then mock up the the rear mount, I really did not like how the rear the mount turned out so I re-made it, you'll see it a bit later.
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Don't like the seat, I'll have to do something about that. But here is the new rear motor mount with tire and fender starting to get mocked up. Found some Harley rotors on eBay that were take offs. Did not want chromed rotors, these work and look great for what I want.

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Man I do not like that seat I had,. How about a shock seat? I just need a new pan with a high back and a shock. Most of the chopper shock type of thing simply do not work they flat suck. I ride mountain bikes so a variable compression shock with rebound would work great. I got a used almost new RP2 shock from eBay. The high volume long version.

I then called sinister seats I also found on Ebay and asked them for a seat with mounts for a shock and a high pan. They said ho problem., While i Was at it I needed bungs in specific sizes and cope, they said no problem, Great getting bungs int the correct size was something I had not solved yet.

The seat mock up and the rear mount and seat shock mount. It is all just tacked it will look good when it is tigged in place. That is my older son holding the shock in the pic.
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Final welds look like this btw...
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I am using 2006 Sportster front end and front caliper. I will be using a Wilwood 2 piston rear caliper. I got the forks on eBay. I also added the clip on bars ala cafe racer. There are many looks out there I like many, it is sometimes hard to pick. For now I am going with cafe/sport bike type bars per the original concept.


So there we have it so far with 2 fender options, I am going wit the shorter look. It is actually the same fender with a little MS Paint magic is all to shorten it.

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Actually in the previous pics I noticed that the forks were a bit too low, I lowed them in the trees and leveled the bike. I also added a MosnterCraftsman kick stand. Here is it so far. You can see the top of the fork tuber are now more level with the clip-ons. I also went with a smaller front wheel instead of the typical 21 incher. It looks a bit older in style to contrast with the newer looking wider rear. Same overall look but gives it a more nostalgic look.

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Ha ha thanks. Actually it took months of course. I just posted the pics in sequence with a narrative, I find it is easier to see what people if it is all in a row so I did it that way to make it easier for people to see almost end to end. I actually built the frame twice, the first one was too long and low for me so I had to rebuild it. I stopped working on it for almost a 8 months as I got side tracked, I just got back to it. I had it on another forum that was more Harley centric and wanted to put it out on XS forum where I can get more help as the time comes.

As it is I have been waiting 5 weeks for jack shaft so I am dead in the water until I get that. Tank is in route to me so maybe I can work on that.
 
Made progress tonight. had a friend with a lathe turn down some tick aluminum tube, it necks through the brake bracket. Here it is installed as well. Not a lot of install options, the bracket interferes with the frame given where the caliper ears are located. So I had to clock it back off the frame and use a bracket arm.
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The carb set up I am using, stock and rebuilt Mikunis.
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Polished the engine cases as well both sides. strip with aircraft stripper, sand with 1000 grit, then use buffing compound on a buffer wheel.
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Since the caliper bracket interferes with the frame tubes, I may cut an inside section flat and put a plate in the tube clearing 3 mm or so allowing the plate to rotate forward. Thing is the angle right now is pretty good in terms of angular momentum, the plate rotates directly down the arms length. I may be able to make it look better but not so sure it will function better. Will need to think not his some.
 
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Got the tank on. It is clear powder coat over bare metal. Fender will be the same and frame in semi gloss black. Harley brake lever looks kinda big, may need metric brake lever. We'll see. This week I'll get jack shaft and fender mounted. Kinda tough, garage is 110 in the morning here in Phoenix.

Still can't decide how much fender to use to cover tire. Looks better longer but shorter highlights the tire. Have to decide here pretty soon.

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haha, didnt notice you were from AZ till I saw the Sidewalk, Trees and roof tops.. . "looks like mine" I said to myslef.. Like every other Arizonian.. lol! Top work, keep it comin.
 
IMHO, the position looks great. :thumbsup:

If you go with the strut, it should be curved and thick, to follow the lines of the bike. :umm:

As far as where it should be to avoid the rocks, I haven't got a clue! :shrug:
 
If you can make it work without the struts I would go that route.

The thing would look really clean.
 
The fender is 13 gauge. Super strong. Got it from Yaffee here locally, only one they had left from their chopper building days 5 years ago. Now days they all deem to be wimpy 18 gauge.

I am going to add a mount behind the seat to the fender as well, a large wide bracket that is unobtrusive. I am hoping I can go wit no struts. :)
 
Sweet build! I'm still gathering parts for mine. How do you like that bender? I'm in the market for one (for my ongoing 4x4 project) and that one is on top of my list.
 
Quick low quality phone pic of the Jackshaft mount, rear fender support and potential rear brake mount. Using Harley master cylinders, Wilwood rear and Harley front caliper. peace of mind with brakes is key for me, did not go with generic ebay or Mikes imported stuff. On the down side the rear master if kinda huge as you can see.

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