Between 485 & 705 SQ/FT Mid-Century Moto Mecca Makeover
- Thread starter sakurama
- Start date
Workspaces between 485 and 705 squarefeet.
Finallygotit
ALLIANCE MEMBER
Thank you! Unfortunately no, sorry. At the time I was in between hot projects and elbow deep in nasty muck so taking pictures was not a priority. Hindsight being what it is, I'm really kicking myself now as a few guys wanted to see a documented rebuild. I really should have taken the time.........
If you need to rebuild the head, it's not that complicated. Your skills being what they are, you will have no problem. If needed, I have a special post that mounts on the table for removing the head. You are more than welcome to use it; no need to buy one.
Kiwi Canuck
Well-known member
That is so cool that you got a nice Bridgeport on the way.
I followed Kristofer from 44 Bikes and when he got his lathe and mill I started the journey to find a lathe and mill for myself.
https://www.garagejournal.com/forum/showthread.php?t=112578&highlight=industrial+design
The problem was I didn't know enough to evaluate what was worth buying and what to pass on and the pickings were very slim up here in Vancouver, B.C. so I started looking at new machines.
After reading ZMotorsports posts about Precision Matthews machines I decided that was the route for me.
https://www.hobby-machinist.com/threads/my-precision-mathews-pm1340gt-arrival.24887/
It still took a good while to narrow down what to buy and then to get them here, but I'm very happy with the Taiwanese made machines I got and it's been a fun few years learning.
I bought the same machines as Mike from Zmotorsports and both with 3 phase motors. Also purchased Hitachi VFD's https://www.ebay.com/p/Hitachi-Wj20...ingle-Phase-Input/1404528561?iid=143079485960 to convert my single phase power to 3 phase, got lots of help from guys over at Hobby Machinist forum and have both machines up and running now.
Here's what my VFD looked like once done.
My 15 year old son doing what he's good at, programming stuff.
And now working on programming the lathe.
My Mill during the build and starting to look finished, just need to install the RPM display in the pod I made and finish the DRO install.
Good luck with your new machine and I look forward to seeing how yours turns out.
If you happen to buy the Hitachi VFD's and need assistance with programming, I have all the programming files in PDF form with pretty good baseline settings and can send them to you.
David.
I followed Kristofer from 44 Bikes and when he got his lathe and mill I started the journey to find a lathe and mill for myself.
https://www.garagejournal.com/forum/showthread.php?t=112578&highlight=industrial+design
The problem was I didn't know enough to evaluate what was worth buying and what to pass on and the pickings were very slim up here in Vancouver, B.C. so I started looking at new machines.
After reading ZMotorsports posts about Precision Matthews machines I decided that was the route for me.
https://www.hobby-machinist.com/threads/my-precision-mathews-pm1340gt-arrival.24887/
It still took a good while to narrow down what to buy and then to get them here, but I'm very happy with the Taiwanese made machines I got and it's been a fun few years learning.
I bought the same machines as Mike from Zmotorsports and both with 3 phase motors. Also purchased Hitachi VFD's https://www.ebay.com/p/Hitachi-Wj20...ingle-Phase-Input/1404528561?iid=143079485960 to convert my single phase power to 3 phase, got lots of help from guys over at Hobby Machinist forum and have both machines up and running now.
Here's what my VFD looked like once done.
My 15 year old son doing what he's good at, programming stuff.
And now working on programming the lathe.
My Mill during the build and starting to look finished, just need to install the RPM display in the pod I made and finish the DRO install.
Good luck with your new machine and I look forward to seeing how yours turns out.
If you happen to buy the Hitachi VFD's and need assistance with programming, I have all the programming files in PDF form with pretty good baseline settings and can send them to you.
David.
Last edited:
Hey Gregor. I just had a quick question about your van's bumpers/tire carrier. I recall you said multiple times you just sprayed them with bedliner to match easily, I just can't remember what you actually sprayed with. Also, how do you find its holding up so far?
Sent from my LG-H873 using Tapatalk
Sent from my LG-H873 using Tapatalk
Wow, they are so CLEAN! I rarely buy new stuff so I'm always wowed by how clean and shiny the new machines are. They look substantial and certainly not hobbyist machines.
I have been using Teco VFD's so I'll probably get another just because I'm familiar with them. And when I finally get a CNC I'm hoping my son will program it for me - seems like a totally reasonable reason to have kids!
Duplicolor Bed Liner with a coating of POR15 as primer. I have about 10,000 miles on the front bumper and so far I have to say it's held up really well. I have seen no chips and we've done a bunch of gravel roads and followed a plow/gravel truck for quite a while in Colorado so there's been abuse. I'm pretty happy with it although I wished it would spray better. It needs to be constantly cleaned as you spray but otherwise no complaints.
Gregor
zmotorsports
ALLIANCE MEMBER
David, glad you finally got your machines. I think you'll be happy with them.
So with just a bit more than two weeks to go to The 1 Moto Show I have my work cut out for me.
Remember when I said, when you have to make a new steering stem it gets trickier? Yeah, I jinxed myself. First though I needed to make a new battery box for the new battery.
I have a Diacro shear and brake but I get a lot of use out of the corner notcher I got a few years ago. Most things on this bike were over built and pretty much everything is made with 1/8" aluminum so there's room to scale back the size of the material. Partly because it's not needed and partly because my tooling can't handle that size material.
I learned that aluminum likes a smaller cup size so I scaled down and saw an improvement. I also went to a 1/16" tungsten and dropped my amperage and for the first time I was getting okay welds on .063 5052 sheet.
I made the brackets a bit larger - I think .090 or something. It's encouraging to see improvement on my aluminum welding. It's good to know that all that YouTube watching is finally paying off.
Like everything on this bike nothing is easily accessible and so my battery box needed to be cut down in order to get the battery in and out while the box was bolted in. Still, that's one thing I can check off the list.
Next up is the forks. I thought I might get lucky but the bearings were a bit different and the stem was just a bit too short.
I hoped to just reuse the stem and even considered cutting it and then welding in an extension plug. No, the bearings wouldn't work with the races installed in the bike and the local bearing place didn't have anything larger than the 28mm ID in the 52mm OD that I needed.
I pressed out the KTM fork's stem and then made a detailed drawing of it.
I redid my drawing to combine the bearing sizes from the original BMW, the stem sizes of the KTM forks and the length to make them work.
And as a happy coincidence the KTM fork stem has no large external threads that I'd have to cut on the lathe - only a stem nut that I was able to find a tap for in 20x1.5mm so I used the tail stock of the lathe to help hold the tap straight and then rotated the chuck by hand to tap the stem.
I screwed up the first effort by missing a number but the second one worked out. There's a lot of different fits on a stem. The bottom is a medium press fit, the lower bearing is a medium press fit and the upper bearing is a tight slip fit and the top clamp is a loose slip fit. All of those require very precise machining and if you miss by anything more than a half a thou it doesn't work.
I don't use my 6-jaw chuck when I do something of this precision. I could use the four jaw but my 5C collet closer is a very fast and super accurate way to hold the material and I can remove and replace it if needed. That, combined with a live center (cone on a bearing) in the tail stock and I can hold really tight tolerances.
Second attempt worked out.
Tomorrow I'm going to try to get the forks in and then Thursday I'll go get some tires up at Golden Tyre West who is giving me a sponsorship deal. It's nice to have a deal with them as I've been buying the tires for the last 3 or so years and they're my favorites. So win win.
I need this thing on wheels by the weekend.
Gregor
Remember when I said, when you have to make a new steering stem it gets trickier? Yeah, I jinxed myself. First though I needed to make a new battery box for the new battery.
I have a Diacro shear and brake but I get a lot of use out of the corner notcher I got a few years ago. Most things on this bike were over built and pretty much everything is made with 1/8" aluminum so there's room to scale back the size of the material. Partly because it's not needed and partly because my tooling can't handle that size material.
I learned that aluminum likes a smaller cup size so I scaled down and saw an improvement. I also went to a 1/16" tungsten and dropped my amperage and for the first time I was getting okay welds on .063 5052 sheet.
I made the brackets a bit larger - I think .090 or something. It's encouraging to see improvement on my aluminum welding. It's good to know that all that YouTube watching is finally paying off.
Like everything on this bike nothing is easily accessible and so my battery box needed to be cut down in order to get the battery in and out while the box was bolted in. Still, that's one thing I can check off the list.
Next up is the forks. I thought I might get lucky but the bearings were a bit different and the stem was just a bit too short.
I hoped to just reuse the stem and even considered cutting it and then welding in an extension plug. No, the bearings wouldn't work with the races installed in the bike and the local bearing place didn't have anything larger than the 28mm ID in the 52mm OD that I needed.
I pressed out the KTM fork's stem and then made a detailed drawing of it.
I redid my drawing to combine the bearing sizes from the original BMW, the stem sizes of the KTM forks and the length to make them work.
And as a happy coincidence the KTM fork stem has no large external threads that I'd have to cut on the lathe - only a stem nut that I was able to find a tap for in 20x1.5mm so I used the tail stock of the lathe to help hold the tap straight and then rotated the chuck by hand to tap the stem.
I screwed up the first effort by missing a number but the second one worked out. There's a lot of different fits on a stem. The bottom is a medium press fit, the lower bearing is a medium press fit and the upper bearing is a tight slip fit and the top clamp is a loose slip fit. All of those require very precise machining and if you miss by anything more than a half a thou it doesn't work.
I don't use my 6-jaw chuck when I do something of this precision. I could use the four jaw but my 5C collet closer is a very fast and super accurate way to hold the material and I can remove and replace it if needed. That, combined with a live center (cone on a bearing) in the tail stock and I can hold really tight tolerances.
Second attempt worked out.
Tomorrow I'm going to try to get the forks in and then Thursday I'll go get some tires up at Golden Tyre West who is giving me a sponsorship deal. It's nice to have a deal with them as I've been buying the tires for the last 3 or so years and they're my favorites. So win win.
I need this thing on wheels by the weekend.
Gregor
Hostyle
Well-known member
Great work as always Gregor!
BORING HOP YARD
Well-known member
Greetings Gregor, are you using McGuire Bearing on Market St in Portland ?
That's been our go to for years.
That's been our go to for years.
zmotorsports
ALLIANCE MEMBER
Beautiful work as always Gregor. Your aluminum welding looks great to me.
Thanks!
Yes, they seem to never have what I need in stock so I buy it at McGuire and then drive out to Royal. That generally means I get to stop at Metal Supermarket for a material run.
Thanks Mike, your thread(s) are a real inspiration for me and your shop - someday I hope to have that space!
Gregor
zmotorsports
ALLIANCE MEMBER
Thank you.
polexican23
Banned
any chance that bridgeport is in or is near Illinois. That auction site looks awfully familiar to me.
polexican23
Banned
maybe all these auction houses use the same software. I just checked out Hoff and it looks the same as the one i keep up on.
Vertigo Cycles
Well-known member
can you hang your phone from your neck and give us all a live feed of that bike going together? It's projects like yours that make me thankful for platforms like Instagram
I just hate video but IG stories have no pressure to them. They disappear in a day and have a 1 minute limit so the constraints are helpful. I dare say that I find them sort of fun to shoot despite the fact that I hate IG for it's vertical format.
Nonetheless I have some catching up to do here which probably won't get us current but I need a break from the shop. So, last thing was the steering stem...
I think the thing that I find amazing is that I don't really find it amazing when the parts turn out. I messed up the first try on the stem because I misread the drawing but the second one I hit every number. It press fit together perfectly. Since I'm using odd bearings I like to make notes when I can as to what the bearings are - and leave them for the next owner.
I put the bearings in and installed the triple clamp and it was a dead nuts perfect fit. Better, in fact, than the one that came out of the bike. And they look the business too.
As I'm waiting for wheels I work on the things for which I have parts and yesterday the package came from Highway Dirt Bikes.
I can't really leave well enough alone so I counter sink this bracket as it streamlines the mounting.
My new favorite trick is that 12 point sockets can drive square things like taps. Especially big taps. The Milwaukee 3/8" ratchet can break your wrist if you're not careful but man it makes quick work of tapping. I'm so glad that I got the more powerful brushless version.
The cockpit is coming together. Not sure what brake master I'm going to go with as I have a few choices but most likely the stock KTM one for now.
While the wheels aren't here yet I reached out to Golden Tyre a couple weeks ago about getting a sponsorship and they liked the idea. I drove up to Vancouver, WA to meet with Dax and pick out the tires for the bike.
Their warehouse smelled so good. It smelled like traction.
He suggested the same tires their riders are using in the Dakar rally right now - the 723R's. One of the things that got me to convert to Golden a few years ago was their "Fatty" front tires. Nothing else is quite like them and it's all I've run for the last few years so I am excited to get one on the big BMW.
Next up is to convert the rear end of the bike over to the disc brake R1100 rear bevel drive. Then make a rear brake. I'm excited but it's going to be a stupid amount of work - it's going to take all weekend most likely.
Gregor
Last edited:
Hostyle
Well-known member
That warehouse shot is gold!
Do you still work for Rev'it?
Do you still work for Rev'it?
Madc
Well-known member
Gregor,
as always thank you for the updates, amazing work and documentation. I may have missed it in the past but what is the red tiered tool box in the background of the handlebar image that looks like a Hazet assistant?
Thank you again,
MADC
as always thank you for the updates, amazing work and documentation. I may have missed it in the past but what is the red tiered tool box in the background of the handlebar image that looks like a Hazet assistant?
Thank you again,
MADC
Yes, and no. Most of the images you’re seeing now (social and web) were done during our last shoot here in Portland.
It’s a Japanese copy of the Hazet called a Hory Caddy. Probably harder to find and from the 60’s I think but generally cheaper and functionally identical. It was great for racing or if you have a large shop but it’s probably on its way out as I try to find more space.
Gregor
The shift lever on the bike when I got it was pretty clapped out. I made this one because I thought it would be cool and because I can weld stainless better than aluminum.
So when I replaced the rear end with a disc brake bevel I needed to convert the bike to hydraulic brakes which I didn't have too much of a plan for but I knew the brake should match the shifter...
To start I lopped off most of the bracket for the drum brake.
I could have drilled a couple of holes for the rear brake master but I wanted to make a decent bracket for it. I also wanted to make sure that it had captured fasteners - something of a pet peeve of mine. There's no good reason to use a nut on the back of something if the bracket can be threaded and the process of working on the assembly simplified.
I milled the piece of stock recessed and then drilled and threaded it for the master cylinder then welded it in place. Now it's recessed and your boot won't hang up on it and you can simply unscrew it. I love these sorts of details. When I would work on my factory Honda race bike - the RS125 - it was all about making it easy to work on and it was a pleasure. I want my bikes to be easy to work on.
With the master in place it was time to turn to the rear brake lever. I had a few sketches and knew I wanted to use the same 1/2" stainless tubing and to make it sort of trellised so I started with that idea and made a couple of scraps to weld.
I'm embarrassed to admit this but I was watching a video on Weldingtipsandtricks.com and I couldn't understand the rule of 33's for stainless. Long story short I have spent my whole life on this machine not understanding the "percentage on" aspect of the pulser. I thought for some reason that it was peak amps and not percentage and I've always tried to figure it out but never did.
Until today.
It's that sort of bittersweet thing that you're thrilled to learn and upset that you've spent years being an idiot not being able to take advantage of the settings of your machine. So it turns out that adjusting the percentage of "on" time really makes a big difference with stainless, same with pulses set at 33pps. Suddenly it's much easier to control the puddle and the heat and it doesn't get away from you and keyhole.
Making the cuts on stainless bar for the toe part.
Used the hydraulic press, a rod of steel and a piece of aluminum that I cut a hole in for the die.
The "eye" for the actuating lever.
And a few of the parts coming together. I am also using a needle bearing on this so that it has a nice feel. Again, small detail, no one will notice it but I'll know and feel good about it.
I love this style of making a tubular structure where the tubes join in another open tube. It looks light and trick and it's strong.
Here I put my boot on the peg to check the fit of the next part. I don't think it's going to be quite strong enough without a brace and so I'm going to try to bend one and then brace it I think. I ordered another die for my JD Squared bender so I'm going wait on that.
Luckily my wheels from Woody showed up and I could move onto something else.
They are just stunning. I'm going to run them with a Tubliss setup and see how that goes. If you're not familiar this system runs a very small inner tube inside of what is sort of a liner. This small tube inflates to 110psi against the liner and basically creates a full wheel bead lock allowing you to then inflate the tire without a normal tube. The advantage is that you can run very low pressure and you can't pinch flat. I've used it for a few years and like it.
They look very cool but more importantly they're quite bit lighter. Not as light as I hoped but almost 17lbs is a pretty good savings. That brings the bike down to 410lbs.
So the front went on with no issues - which is to be expected as it's a complete KTM front end...
And the rear did not.
Not even close. I was worried about this and asked in the bike thread if anyone had done this and if it would fit and someone showed me a photo of their bike with an 18" rim and knobby and it just cleared. What happened is that when I sat down with Woody to make the lightest and best rims we choose the A60's in a narrower 2.15 width which is a normal dirt bike width. This squeezes the tire tighter making it more round and pulling the knobs around and, most importantly, making it taller.
I didn't think about that last part.
I have been in panic mode for most of tonight. I have less than two weeks and a $2500 set of amazing wheels that don't fit. A magazine is waiting on photos of the updated bike. The logical thing would be to find another tire that would fit. The illogical thing would be to find someone who can help me cut the swingarm apart and reposition the shock mount.
You can guess which option I want. I've reached out to Heath - the guy who welded the tanks for me - and I haven't heard back from him yet. I don't trust my aluminum welding to that degree yet but Heath I trust. Fortunately someone on Instagram saw my post and sent me photos of a swingarm that was modified exactly as I was thinking so the precedent is there and the idea is sound.
And I thought I'd be done early...
Gregor
So when I replaced the rear end with a disc brake bevel I needed to convert the bike to hydraulic brakes which I didn't have too much of a plan for but I knew the brake should match the shifter...
To start I lopped off most of the bracket for the drum brake.
I could have drilled a couple of holes for the rear brake master but I wanted to make a decent bracket for it. I also wanted to make sure that it had captured fasteners - something of a pet peeve of mine. There's no good reason to use a nut on the back of something if the bracket can be threaded and the process of working on the assembly simplified.
I milled the piece of stock recessed and then drilled and threaded it for the master cylinder then welded it in place. Now it's recessed and your boot won't hang up on it and you can simply unscrew it. I love these sorts of details. When I would work on my factory Honda race bike - the RS125 - it was all about making it easy to work on and it was a pleasure. I want my bikes to be easy to work on.
With the master in place it was time to turn to the rear brake lever. I had a few sketches and knew I wanted to use the same 1/2" stainless tubing and to make it sort of trellised so I started with that idea and made a couple of scraps to weld.
I'm embarrassed to admit this but I was watching a video on Weldingtipsandtricks.com and I couldn't understand the rule of 33's for stainless. Long story short I have spent my whole life on this machine not understanding the "percentage on" aspect of the pulser. I thought for some reason that it was peak amps and not percentage and I've always tried to figure it out but never did.
Until today.
It's that sort of bittersweet thing that you're thrilled to learn and upset that you've spent years being an idiot not being able to take advantage of the settings of your machine. So it turns out that adjusting the percentage of "on" time really makes a big difference with stainless, same with pulses set at 33pps. Suddenly it's much easier to control the puddle and the heat and it doesn't get away from you and keyhole.
Making the cuts on stainless bar for the toe part.
Used the hydraulic press, a rod of steel and a piece of aluminum that I cut a hole in for the die.
The "eye" for the actuating lever.
And a few of the parts coming together. I am also using a needle bearing on this so that it has a nice feel. Again, small detail, no one will notice it but I'll know and feel good about it.
I love this style of making a tubular structure where the tubes join in another open tube. It looks light and trick and it's strong.
Here I put my boot on the peg to check the fit of the next part. I don't think it's going to be quite strong enough without a brace and so I'm going to try to bend one and then brace it I think. I ordered another die for my JD Squared bender so I'm going wait on that.
Luckily my wheels from Woody showed up and I could move onto something else.
They are just stunning. I'm going to run them with a Tubliss setup and see how that goes. If you're not familiar this system runs a very small inner tube inside of what is sort of a liner. This small tube inflates to 110psi against the liner and basically creates a full wheel bead lock allowing you to then inflate the tire without a normal tube. The advantage is that you can run very low pressure and you can't pinch flat. I've used it for a few years and like it.
They look very cool but more importantly they're quite bit lighter. Not as light as I hoped but almost 17lbs is a pretty good savings. That brings the bike down to 410lbs.
So the front went on with no issues - which is to be expected as it's a complete KTM front end...
And the rear did not.
Not even close. I was worried about this and asked in the bike thread if anyone had done this and if it would fit and someone showed me a photo of their bike with an 18" rim and knobby and it just cleared. What happened is that when I sat down with Woody to make the lightest and best rims we choose the A60's in a narrower 2.15 width which is a normal dirt bike width. This squeezes the tire tighter making it more round and pulling the knobs around and, most importantly, making it taller.
I didn't think about that last part.
I have been in panic mode for most of tonight. I have less than two weeks and a $2500 set of amazing wheels that don't fit. A magazine is waiting on photos of the updated bike. The logical thing would be to find another tire that would fit. The illogical thing would be to find someone who can help me cut the swingarm apart and reposition the shock mount.
You can guess which option I want. I've reached out to Heath - the guy who welded the tanks for me - and I haven't heard back from him yet. I don't trust my aluminum welding to that degree yet but Heath I trust. Fortunately someone on Instagram saw my post and sent me photos of a swingarm that was modified exactly as I was thinking so the precedent is there and the idea is sound.
And I thought I'd be done early...
Gregor
Last edited:
meathooker
Well-known member
Those wheels are beautiful! As always amazing attention to detail. Thanks for the update.
shirk
Well-known member
That must have been heartbreaking to see that rear not clear. I have been following on IG and let out a big "oh nooo" when I saw that.
Sent from my VTR-L09 using The Garage Journal mobile app
Sent from my VTR-L09 using The Garage Journal mobile app
Bob Heine
ALLIANCE MEMBER
Gregor, with time not being on your side, my first thought was have the tire shaved. My friend bought a slightly used 1985 Corvette coupe in 1985. The ride was terrible. He suspected the 255/50-16 Goodyear Gatorbacks were the problem so he took the wheels and tires to a specialist and had the tires shaved true. It was a popular autocross trick back then -- the tread didn't roll over as much.
shirk
Well-known member
Following along intently. Point of no return on that next step.
Sent from my VTR-L09 using The Garage Journal mobile app
Sent from my VTR-L09 using The Garage Journal mobile app
Oh, god. I'm so off the map right now. I keep telling myself, "It's just a motorcycle, it's just a bunch of metal..." but I'm making huge changes to it and I'm way off in uncharted territory.
In fact I'm so nervous that I've just stopped working, put away all the tools, swept and cleaned the mill and will have a coffee until my head is clear. Then I'll go back in and start hacking again. I have 4 hours to solve my issues and deliver the whole thing to Heath to weld it up.
Gregor
shirk
Well-known member
Looks like the coffee said "Damn the torpedoes, full speed ahead!"
Indeed.
So by best estimate the tire overlaps the current swingarm mount by about 1/4-3/8" or about 8-10mm. When you consider that the tire will grow and stretch at speed you need some buffer, maybe 5-8mm and then if you consider mud and rocks in the knobs maybe a bit more.
If I move the mount straight back the width of the swingarm will interfere and block the shock yoke. I decide to go in and up. My initial center point is the upper curve of the casting mark where it joins the straight. This should give me 10-13mm of clearance. More than enough.
First I need to press out the bushing in the swingarm. I made a pressing tool, heated the swingarm up and got nowhere. A BMW mechanic from Germany who's watching the build on IG suggested cutting the bushing to collapse it...
Surprisingly after cutting it on two sides and trying to force, whack and press it out I was getting nowhere.
I went to my goto tool - the 1/2" roughing end mill. It cut the edge of the bushing like butter and out it came.
I decided to select a hole saw that was roughly the outside diamter of the castings mount. My plan was to cut this hole and then cut a billet of aluminum that I could drop in and then weld up. Simple. Ish.
I used the end mill to cut away the part of the mount that was hitting the tire.
Spun up a puck of 6061 aluminum with a 10mm hole - the same as the shock bolt. I figured that when all was said and done I'd need to bore this out to accept another bushing but leaving it the size of the bolt would allow me to continue to mock it up and then at the end I could use that to help position the swingarm to make the final operation.
And done! That wasn't too hard at all. It's clean, simple and should have plenty of material to support it. I am so relieved...
Except it doesn't fit. The shock yoke hits the swingarm at full extension...
I use the same roughing end mill and draw a line to show the angle of the shock. I then start going full 3D Etch-A-Sketch with the hand wheels to try to cut at an angle. There's no way to tip the swing arm up and machine straight so my only option is to spin the knee and the table traverse at the same time...
****. I keep cutting and fitting, cutting and fitting and it's not fitting. That whole damn chunk needs to be cut out. That was the "take a Nescafe moment" for me. I thought some light cutting might be fixed with maybe a half round of aluminum welded into place but this was going to require something much more... drastic.
I find a 1x3x4" piece of 6061 aluminum and I cut out the whole square on the swing arm. I put it in the mill and machine slots in it to allow the yokes to clear and then clearance the center for the shaft/adjuster ring. I use ball end mills to radius the corners so there's no stress risers or places to propagate cracks. I use the hole saw to index it to the puck and mill the sides of the swingarm to fit the whole thing and then I call Heath to tell him I'm on my way.
Heath dresses the swingarm and the parts a little and considers the approach. He likes the parts and once they're prepped he tacks the flat mount into position using the puck to index it.
The tack welds tell him that the casting is clean and will weld perfectly so he welds the upper mount into position so he can weld the spots that the puck will hide.
Heath makes it look easy. I swear whenever I watch him weld I am somehow convinced that through osmosis and proximity I will be able to go home and weld just like that. Hasn't happened yet.
Despite the awkward and tight positioning Heath runs a continuous and perfect bead all around the part. He radius the part where he needs the bead to be flush and he double dips when he needs to build the bead up. It's amazing to watch.
It turns out perfectly. The billet plate that I made will be far stronger than the casting and the moving that mount in should also make it stronger. Heath shares shop space with a machinist who looked over the solution and thought it was a big improvement. I am hopeful but nervous. What I decided to do was way out there and not done before so it's hard to say until we test it.
When I get home I take the second swingarm and compare them side by side. Now, looking at my solution, I feel that the swingarm is going to be much stronger. It's just got much more material supporting it and there's less leverage acting on it. I could see adding a brace under the mount but I think this is going to work fine.
I am finally not nervous for the first time in two days.
I still have a lot to do but this fire is out. I'm hoping that there's no more. I need to source new bearings for the swingarm, get a new bushing and bore the mount out to accept that and then press that in. Brake lines, throttle lines, controls... small stuff that will take time.
Oh, ****, I forgot I have to finish building that brake lever...
Gregor
shirk
Well-known member
Amazing work. Thank you for all the details shared for us following along.
Sent from my VTR-L09 using The Garage Journal mobile app
Sent from my VTR-L09 using The Garage Journal mobile app
Robust2
Member
Long time reader and lurker here and I have to say, being able to follow your build on Instagram definitely adds a whole new level of immersion for us fans!
I got quite a chuckle seeing the same infrared thermometer being used by you in the garage to monitor the temperature of the swingarm while getting the bearing out, and immediately after by your wife in the kitchen to make swiss buttercream.
Do you have any idea what the effects of shortening the mount will be on your geometry? I would think the rear might come up quite a bit?
I got quite a chuckle seeing the same infrared thermometer being used by you in the garage to monitor the temperature of the swingarm while getting the bearing out, and immediately after by your wife in the kitchen to make swiss buttercream.
Do you have any idea what the effects of shortening the mount will be on your geometry? I would think the rear might come up quite a bit?
Last edited:
Thanks, it’s certainly dramatic for me too!
I don’t know exactly how it will change. My hope is that it raises the rear, gives an .5-1” more travel, slightly stiffens the suspension and puts a bit more weight on the front. It will steepen the head angle which I know I’ll like as that sharpes/quickens the steering. The bike is very neutral right now so this will give it a bit of aggression - hopefully.
This is a lot of work to run such big aggressive tires but it should improve its ability to be ridden like a dirt bike.
The bike is certainly living up to its expectations as a test mule for ideas.
Gregor
polexican23
Banned
watching on IG..."oh **** Gregor done fucked up now"... read GJ, damn Gregor just went and worked some magic again.
Terranova
Well-known member
Situations like this always lead me to think in a chicken/egg fashion.
Are you good at saving your *** because you find yourself "here" often or do you *allow yourself* to "get here" often because you're good at saving your ***?? (and lucky).
fastev
Well-known member
While the wheels aren't here yet I reached out to Golden Tyre a couple weeks ago about getting a sponsorship and they liked the idea. I drove up to Vancouver, WA to meet with Dax and pick out the tires for the bike.
Gregor
I race RC cars with Dax. You ought to come out to the track one evening. Like you need something else to do...
I too am enjoying following along and am thoroughly impressed with the swingarm mod.
I too was wondering how the geometry change would affect stance/travel and stiffness. I agree with you that the rear looks like it will come up a bit and the travel will increase a bit if everything else clears for the entire travel of the spring/shock. My thinking on the stiffness is the opposite of yours as I think this will soften it slightly. I think this because you are moving the shock mount closer to the swing arm pivot point without changing the spring rate.
Regardless, this thread continues to impress and is one of the few I regularly check in on. Looking forward to seeing the bike finished. Keep it up.
Sent from my SM-G930W8 using Tapatalk
I too was wondering how the geometry change would affect stance/travel and stiffness. I agree with you that the rear looks like it will come up a bit and the travel will increase a bit if everything else clears for the entire travel of the spring/shock. My thinking on the stiffness is the opposite of yours as I think this will soften it slightly. I think this because you are moving the shock mount closer to the swing arm pivot point without changing the spring rate.
Regardless, this thread continues to impress and is one of the few I regularly check in on. Looking forward to seeing the bike finished. Keep it up.
Sent from my SM-G930W8 using Tapatalk