78 XS750 chop first bike build

[Rjcinelli]

Yup,some progress is better than none. Is that rear wheel an 18"? Have you considered swappin' it to a 16"? Looks like it should work with one from a XS1100:

Thread: swapping just rear wheels between xs750/1100
"Hi, check the thread on this, I have a xs750 rim on a xs1100, 1980, with no modifications needed. So the reverse should also be ok."
http://www.xs11.com/forum/showthread.php?t=26208

And one o' those won't break your account much - just one example:
Attachment 83839
Price: US $37.00
https://www.ebay.com/itm/78-81-YAMAH...QAAOSwEUdaXl3e

I hadn't thought about going to a 16" but yes it's an 18" in the rear, I just ordered a new rear tire already or I would jump on a 16"

I am still trying to convince my buddy to give me his spoked rear shaft drive wheel from his Suzuki though, tough to convince him!

[TriNortchopz]

I hadn't thought about going to a 16" but yes it's an 18" in the rear...
I am still trying to convince my buddy to give me his spoked rear shaft drive wheel from his Suzuki though, tough to convince him!

If your buddy don't wanna give up his spoked Suzi rear wheel, build your own; just need another trip to your friendly ($20) machinist:

From yamaha-triples.org
2007 Thread:Wire Wheel Options...

Q: "There has to be another option for wire wheels. I am going for a cafe/sport bike look on my project and really want wire. What other options are there?"

Best answer, by SwaggeringPagan:
"There is another option that appears to unexplored by anyone here.

Machining.
When you get down to it, the wheel and more importantly the hub center is just a hunk of cast aluminum. That's it. Nothing there is chipped from unobtainium. I run a small custom machine and prototype shop so I tend to think in this direction when I run into something that doesn't readily show a solution.

Take a look at the hub portion of your rear wheel. Cut away the spokes and rim, chuck it into a lathe and skin it just to the point that you have a flat relatively smooth outer surface and suddenly the possibilities are endless.
Now....say you have an old aluminum motorcycle hub from a spoked rim, especially if it's a spoked/disc brake hub....it'll suit perfectly. Take that nifty old bare hub, knock out the bearings and anything else rattling around inside the axle bore then chuck that lump into your favorite metal chewing lathe and bore the inside out to just 2 thousandths smaller than your previously turned XS hub. While you're making chips, hog out three 1" diameter holes evenly spaced (120 degrees apart for the math whiz out there) in the hub between the spoke rings....these will come in handy later. I would also add a small 1/8" chamfer to the inside edges of the spoke hub.
Toss your now shaved XS hub in the freezer over night and your cored out spoke hub in an old kitchen over for 1/2 hour at 250 degrees to relax it and let it expand a hair. You don't need to melt it damnable thing, just heat it up. When you're ready to mate them, set the chilly XS center on a nice flat surface, grab your toasty spoked section (with proper insulated gloves you goofballs!!) and quickly slide the two together. I like to add about 300 pounds of weight on top (inline with the axle bore) and let the temps equalize. You'll hear all sorts of popping and moaning as the two pieces of metal even out and grab quite securely to each other. If all is right in the world, you've paid your dues and the Gods aren't p***ed at you for even thinking about a step thru scooter (Just for running to the grocery store of course!!) then you should end up with a spoked XS hub.

Remember those holes that go thru the hub and the chamfers? Here's where you bust out the TIG welder (or take it to a qualified welder) and stack teeny tiny dimes until it's welded securely.

I haven't done an XS hub, but I've done the machine work for other bike/wheel combos. It works and in the end, even if you paid a shop to take care of it for you...you'll be money ahead when compared to trying ot dig up a GX hub. As well, it'll probably be lighter......that GX hub is chubby.

Just a thought for those out there who might be up for some fabrication."

http://www.yamaha-triples.org/forums...at&setCookie=1

[Rjcinelli]

Well, been a little while since I posted on here. Been semi busy with the bike but also got a lot of rain too. I put the motor in the bike, matching front tire to the rear, mounted the rear fender, mounted the seat (temporary until I fab up a proper fitting pan and seat), tacked the passenger pegs on, did the rest of my gaskets on the motor. I think thats about it.

Still need to get a clutch lever for 1" bars, figure out how to set up the rear brake... Struggling with how to run it front brake pedal to the master cylinder, drill frame for gas tank bungs, I need to finish weld everything, figure out an electronics box and where to mount the battery. Hopefully once that's all done I can figure out how I'm going to rewire the bike. I did add in some supports for the frame too.

Criticism, suggestions, tips etc always welcome.



Decided it was time for a nap on the bike once it was mocked up

Started pouring right after we put the roof on the tent, good timing I suppose.

[Rjcinelli]

My buddy who's helping out with the welding trying out the passenger seat, gotta make sure to have a comfy seat for the women ��

[TriNortchopz]

Below are a few threads for electric box building, which may help.
Can you post good pics of the neck area - I'm interested to see how that worked out. And how about a couple of good side views? And a good straight on shot from the front, with the bike level.
What do you mean by, "...figure out how to set up the rear brake... Struggling with how to run it front brake pedal to the master cylinder". Do you mean operate rear brake with handlebar lever?


Steff's xs #7 Electrics Box...
"...I think 1.6mm steel is the best balance between strength. lightness and ease of welding.
Chain is an issue with any electrics box planning. Chain bows out at speed and allowance needs to be made for its position when suspension is fully compressed. A few marks are made on the tyre allowing an extra half an inch to be safe... nothing much more agravating than a rattling chain..."
http://www.choppersaustralia.com/for...hp?f=60&t=7153

#8 Simon's Yammy... kicker, electrics box & motor mods...
"Simon liked the idea of using an extinguisher to house the coils and fuses. I suggested a small lithium iron battery so that could be fitted in as well and keep the bike nice and tidy and simple, and this was the road we then took..."
http://www.choppersaustralia.com/for...hp?f=60&t=7422

GSX chopper #4 Electrics box...
Step one is always planning and takes time if you are to end up with a job that not only looks good, but will last and most importantly is user friendly.
http://www.choppersaustralia.com/for...hp?f=60&t=8302

This is a series of threads that may be of interest to you; a stock KZ750 twin to rigid chop:
Jett's 750 Kawa chopper...
http://www.choppersaustralia.com/for...hp?f=60&t=8069

#2: Jett's 750 Kawa chopper #2...
http://www.choppersaustralia.com/for...hp?f=60&t=8095

#3: Jett's KZ750 chopper #3 rear guard, sissy bar, tank...
http://www.choppersaustralia.com/for...hp?f=60&t=8105

#4: Jett's KZ finished...
http://www.choppersaustralia.com/for...hp?f=60&t=8338

[Rjcinelli]

Below are a few threads for electric box building, which may help.
Can you post good pics of the neck area - I'm interested to see how that worked out. And how about a couple of good side views? And a good straight on shot from the front, with the bike level.
What do you mean by, "...figure out how to set up the rear brake... Struggling with how to run it front brake pedal to the master cylinder". Do you mean operate rear brake with handlebar lever?


Steff's xs #7 Electrics Box...
"...I think 1.6mm steel is the best balance between strength. lightness and ease of welding.
Chain is an issue with any electrics box planning. Chain bows out at speed and allowance needs to be made for its position when suspension is fully compressed. A few marks are made on the tyre allowing an extra half an inch to be safe... nothing much more agravating than a rattling chain..."
http://www.choppersaustralia.com/for...hp?f=60&t=7153

#8 Simon's Yammy... kicker, electrics box & motor mods...
"Simon liked the idea of using an extinguisher to house the coils and fuses. I suggested a small lithium iron battery so that could be fitted in as well and keep the bike nice and tidy and simple, and this was the road we then took..."
http://www.choppersaustralia.com/for...hp?f=60&t=7422

GSX chopper #4 Electrics box...
Step one is always planning and takes time if you are to end up with a job that not only looks good, but will last and most importantly is user friendly.
http://www.choppersaustralia.com/for...hp?f=60&t=8302

This is a series of threads that may be of interest to you; a stock KZ750 twin to rigid chop:
Jett's 750 Kawa chopper...
http://www.choppersaustralia.com/for...hp?f=60&t=8069

#2: Jett's 750 Kawa chopper #2...
http://www.choppersaustralia.com/for...hp?f=60&t=8095

#3: Jett's KZ750 chopper #3 rear guard, sissy bar, tank...
http://www.choppersaustralia.com/for...hp?f=60&t=8105

#4: Jett's KZ finished...
http://www.choppersaustralia.com/for...hp?f=60&t=8338

Thank you for that, I'll be going through all of those when I have time. Class is kicking my ass right now so might be slow progress.

As for the brake, I worded that terribly I'm sorry. I meant that I have been struggling with how to mount and run the parts I guess. Once I mount the rear brake pedal, I can't really seem to figure out how to set up the spring and part that pushes into the master cylinder. Hope that helps clarify. My buddy was wondering if I could run a mechanical disc brake, but I don't think that's really possible?

I'll try to get better pictures when I get over there to work on it, looking like maybe Thursday this week. I will be adding a reinforcement from lower portion of the neck to the top tube of frame.

[Rjcinelli]

Mainly just some pictures that TriNortchopz requested. Started working on the rear brake setup, I think I've got it figured out now but didn't have enough time in the day to get that started. Got the tank bungs tacked in place, and foot pegs. This weekend looks like it's going to rain most of the time so maybe I'll start going through the wiring harness to get an idea for the new one I'm going to be making.

[datadavid]

Umm... you buddys welds look unsafe..

[TriNortchopz]

Umm... you buddys welds look unsafe..

Yup, looks like the welds were too cold, so not proper penetration, and a weak weld;




I wanted that straight on front shot with the bike level was to see if the neck was in alignment. A horizontal frame tube from the bottom of the neck, tied into the two front downtubes, and tying in under the backbone (under the tank) - properly welded - would add some strength.

[tedjames]

Umm... you buddys welds look unsafe..

yeah, hopefully your riding on all freshly paved smooth roads

[Rjcinelli]

Yup, looks like the welds were too cold, so not proper penetration, and a weak weld;




I wanted that straight on front shot with the bike level was to see if the neck was in alignment. A horizontal frame tube from the bottom of the neck, tied into the two front downtubes, and tying in under the backbone (under the tank) - properly welded - would add some strength.

I can try to get a better picture of his finished welds, I agree most of the welds on there right now are not full penetration, but he has just tacked 90% of the stuff on. When he actually welds it all up, he burns right through the rack and gets good penetration. How does this one look? The motor mounts are the only fully welded part right now.

[TriNortchopz]

Here's what you want:


How is that new lower frame rail attached to the XS frame section?

[Rjcinelli]

Here's what you want:


How is that new lower frame rail attached to the XS frame section?

That part was also fully welded whoops, didn't have a picture of that specifically. Slugged it, plugged the slugs, then welded all the way around. I can try to get a picture of that

[Rjcinelli]

Umm... you buddys welds look unsafe..

Got some more pictures of stuff I saw fully welded or not just "tacked" let me know what you guys think. I appreciate the heads up and if you think these welds are still too cold or too hot or junk please let me know so I can either talk to him about it or get my cousin who is a professional welder to do it....he's always working though so if my buddies welds are junk tell me and I will spend the money to have someone do it well.





TriNortchopz here's a picture from as straight on as I could get while bringing the bike inside.

Motor is not bolted in as I started to unbolt it so I could remove it. Easier to get the bike over the hump of door frame without it in.

[Rjcinelli]

yeah, hopefully your riding on all freshly paved smooth roads

How do the welds look that I just posted pics of?

[TriNortchopz]

Well, like alotta things, it looks good from a distance; the one in the third pic of the top crossrail looks okay.

We saw this:

and this:

which resulted in this:


As others said, the welds do not look safe. A concern is for safety, for yourself, passenger, and anyone around if it fails, and will result in ingraining the old theory, "choppers are not safe".

Those tacks look more like welds, and if that were mine, I would grind them down and redo them and avoid overheating the areas to reduce stress and mis-alignment. You said your buddy "When he actually welds it all up, he burns right through the (t)ack...". That'll create lots of heat, not what you want. Maybe a bit more research on welding a chopper frame so you can teach your welder buddy, such as welding each connection in 4 sections. Got all the main frame parts done? Have you taken the time to check alignment - still got that rough 'frame jig'? In that pic from the rear, ^^ it looks like the rear wheel is leaning to the right. Use a simple carpenter level to the check if the top of engine, rear axle and lower frame rails are all level and not twisted. Run a centreline (drawn, or a even just a stringline ) under the bike, then centre the frame, then check to see of rear is centered, then run a centered pipe or dowel through the neck to see if it meets the centreline under the bike

Here is a thread on that process:

"Our first job was to set the frame up and check it was true. A simple way you can do this is illustrated here. A big sheet of particle board (not MDF) is levelled then has a line drawn down the centre. The frame is then set on the board and also levelled (with small wooden wedges if needed).

The centre line of the frame is found. On the shovel the swing arm is centred so a piece of duct tape is used to mark centre (green arrow) and a plumb bob used. Up front a plumbob (blue arrow) is hung off the centre of the steering head. both plumbobs are aligned with the line on the board.

75x35 building timber pieces are used to secure the frame to the board. To check steering head alignment, we use a laser I have built (, but if you are careful, you can use a straight piece of round bar or tube centred in the steering head. On this frame the laser point hits the line indicating a straight frame..."
http://www.choppersaustralia.com/for...hp?f=60&t=8322

[Rjcinelli]

Well, like alotta things, it looks good from a distance; the one in the third pic of the top crossrail looks okay.

We saw this:

and this:

which resulted in this:


As others said, the welds do not look safe. A concern is for safety, for yourself, passenger, and anyone around if it fails, and will result in ingraining the old theory, "choppers are not safe".

Those tacks look more like welds, and if that were mine, I would grind them down and redo them and avoid overheating the areas to reduce stress and mis-alignment. You said your buddy "When he actually welds it all up, he burns right through the (t)ack...". That'll create lots of heat, not what you want. Maybe a bit more research on welding a chopper frame so you can teach your welder buddy, such as welding each connection in 4 sections. Got all the main frame parts done? Have you taken the time to check alignment - still got that rough 'frame jig'? In that pic from the rear, ^^ it looks like the rear wheel is leaning to the right. Use a simple carpenter level to the check if the top of engine, rear axle and lower frame rails are all level and not twisted. Run a centreline (drawn, or a even just a stringline ) under the bike, then centre the frame, then check to see of rear is centered, then run a centered pipe or dowel through the neck to see if it meets the centreline under the bike

Here is a thread on that process:

"Our first job was to set the frame up and check it was true. A simple way you can do this is illustrated here. A big sheet of particle board (not MDF) is levelled then has a line drawn down the centre. The frame is then set on the board and also levelled (with small wooden wedges if needed).

The centre line of the frame is found. On the shovel the swing arm is centred so a piece of duct tape is used to mark centre (green arrow) and a plumb bob used. Up front a plumbob (blue arrow) is hung off the centre of the steering head. both plumbobs are aligned with the line on the board.

75x35 building timber pieces are used to secure the frame to the board. To check steering head alignment, we use a laser I have built (, but if you are careful, you can use a straight piece of round bar or tube centred in the steering head. On this frame the laser point hits the line indicating a straight frame..."
http://www.choppersaustralia.com/for...hp?f=60&t=8322

Thank you, I will do that next time I'm over there working on it and see if it is all level and straight. When I do I'll let you know the results

[Luky]

Text eliminated to save space.

COMMENT:
5 inches ground clearance is normal. But remember if you
have 4 exhausts under the bike you will need that extra space!

[Luky]

I hadn't thought about going to a 16" but yes it's an 18" in the rear, I just ordered a new rear tire already or I would jump on a 16"

I am still trying to convince my buddy to give me his spoked rear shaft drive wheel from his Suzuki though, tough to convince him!

A 16,18,21 will all be about 26" OD with the tire on give or take 1/2 inch.
Check TIRE OD's

[Luky]

Thank you, I will do that next time I'm over there working on it and see if it is all level and straight. When I do I'll let you know the results

The welds on that photo fail the first level of inspection VISUAL INSPECTION.
It all needs to be carefully ground down to basic tubing and welded by a competent welder.
Pay for it if you have to! IT is your life!!!

I am a certified welder and a certified welding inspector through the American Welding Society.