Topic: AmateurHour890_duncwerks

[dunc]

When I first went to dual  disc I used adjusters.. after pulling the wheel about twice, I took them  off. When i chromed my forks, i cut the adjuster part right off.
 Some will say you need them, up to you to decide.

Well said.

[Godffery]

Looks like a bit of milling machine work.  If I was lightening those, I would suit can the adjuster, and mill a big window in there.
 Then the spacers, take a bunch off the sides, similar to the rear brake side spacer on the 750 up to76.

As in remove the adjuster? Then mill out the center of the piece horizontally?

Additionally - are the adjusters really needed?

That may be a bit aggressive of a cut out, I have done a few using a 45 degree pointed mill tool.
 It's kind of  hard to see in this image but it is the only one I have online:


 I also Pitch those adjusters over my shoulder & never look back.

[dunc]

Looks like a bit of milling machine work.  If I was lightening those, I would suit can the adjuster, and mill a big window in there.
 Then the spacers, take a bunch off the sides, similar to the rear brake side spacer on the 750 up to76.

As in remove the adjuster? Then mill out the center of the piece horizontally?

Additionally - are the adjusters really needed?

That may be a bit aggressive of a cut out, I have done a few using a 45 degree pointed mill tool.
 It's kind of  hard to see in this image but it is the only one I have online:


 I also Pitch those adjusters over my shoulder & never look back.

Looks good and I'll toss mine out too. Not planning on modifying these anymore once I get them.

That 550 looks sweet.

[scottly]

I did the work on the arms with a ball-end end-mill on a manual machine. I left a bit of the web as well as one side of the adjuster hole, but I didn't use the adjusters. The top of the Tee brackets are aluminum from a 550, instead of the steel K7 part. We found this out after Frank sent me a 550 caliper by mistake.
The banjo bolt mod consists of removing the flare seat, and machining a flat surface for the crush washer to seal against. BTW, those copper colored washers under the caliper bolts are plated steel; I had them handy, so I used them.  

[754]

Scott's 750 with gas in it weighs around 410 lbs or less BTW..
 And remember aluminum weighs a third of what steel does..

[scottly]

I wish it was 407 with gas, but that's with no gas.
Dunc, you asked about my current setup:

[754]

That is 410 with 2 liters of gas. Need to get it down a bit more.

[Godffery]

Nice work, do you have the phenolic pistons in there as well?

[dunc]

Nice! The new setup looks good Scottly.

Yes - there's some phenolics in the K7/8 calipers already and I've got an extra set in the drawer here.

Curious to see what my bike weight comes into - going to be making an ALU tank and rear section paired with a good amount of lighter things throughout. At least that's the mantra as I go.

[scottly]

Looks like a bit of milling machine work.  If I was lightening those, I would suit can the adjuster, and mill a big window in there.
 Then the spacers, take a bunch off the sides, similar to the rear brake side spacer on the 750 up to76.

As in remove the adjuster? Then mill out the center of the piece horizontally?

Additionally - are the adjusters really needed?

That may be a bit aggressive of a cut out, I have done a few using a 45 degree pointed mill tool.
 It's kind of  hard to see in this image but it is the only one I have online:


 I also Pitch those adjusters over my shoulder & never look back.

Wow, that is a very nice bike, Jeff!!! Did it ever win BOTM??

[Godffery]

 Thank you Man!
Yes actually it did, back in 2010.

 There are some more pix of it on my web site if you want to check them out.   https://godfferysgarage.com/

[dunc]

Lately, I've been shaving down my frame - removing factory mounting tabs. Considering adding some bracing above the swing arm pivot and between the front engine mounts - nothing too drastic, nor heavy.

Question though - do I need to tie the rear of the frame together with a cross member of some sort? As in a bar or some bent plate over the rear tire? (would certainly accommodate travel under full compression)

I was originally going to do an angled kick up extension of the frame. Since, have decided to go a different direction with an continuous alloy seat pan / rear hump. I could easily put some sort brace there that would remain hidden.  Original idea in attached.

[scottly]

That's a very cool rendering!! Ideally there should be some sort of cross bracing.

[calj737]

Ideally there should be some sort of cross bracing.

There is. The question was about the rear tubes being tied together at the end.

And no, that is not necessary, but I agree with Scottly, that is a cool rendering/design.

[scottly]

Ideally there should be some sort of cross bracing.

The question was about the rear tubes being tied together at the end.

I know.
Dunc, this is how Seeley did it. The brace is vertical when viewed from the side. The Rickman frames had a taller hoop, angled to the rear, IIRC.

[dunc]

Thanks Scottly.

I'm going to do a similar thing and let the sheet aluminum define the rear of the bike - rather than my double hoop design.
I had it tacked up and the frame felt too bulky visually.

[scottly]

Hey Dunc, here is a pic that shows how the 8mm bolt boss on the fork legs have a different offset. The steel rule is sitting on the 6mm bolt bosses, which have the same offset on both fork legs.

[scottly]

Hey Dunc, here are the pics of the set-up for making the rotor spacers: