Re: Crazy Custom Frame Hobbit

That’s not what I meant

I meant bronze brazing

The alumaloy sticks tend to have lots of cavitation (air bubbles) and doesn’t seal great.

Might work as the tubing is real aluminum and not shitty cast.

Re: Crazy Custom Frame Hobbit

86 gsxr is unreal are those original plastics?

Re: Crazy Custom Frame Hobbit

Colin Ratcliff /

Ahhhh makes sense.

And yes! Original plastics! It's so incredibly fun. Narrow power band with a ton of power kinda feels like 2t

Re: Crazy Custom Frame Hobbit

Colin Ratcliff /

Hey! So the intake is all together and it's great, but I'm having a hell of a time getting all of the welds to be air tight. Any advice? When I blow into it there's a ton of tiny air leaks, and when I patch one another leak seems to inevitably crop up.

I'm considering either

- grinding down all the welds to be smooth (right now they're a bit blobby) and then smearing another layer on top

- smearing permatex grey on the joints

- painting it

- coating the whole thing in por15

Would love your thoughts! Pictures coming soon!

Re: Crazy Custom Frame Hobbit

I've heard of some people smearing JB Weld in and then going over with the grinder once hard.

Re: Crazy Custom Frame Hobbit

Tweaker trash /

> Ryan Graeme Wrote:

> -------------------------------------------------------

> I've heard of some people smearing JB Weld in and then going over with

> the grinder once hard.

Yea that pretty much the only answer! Maybe run a rubber hose over the seams to make ever thing look smooth

Re: Crazy Custom Frame Hobbit

Colin Ratcliff /
PXL_20201026_164500685.jpg
PXL_20201026_164508396.jpg
PXL_20201026_164519100.jpg

Re: Crazy Custom Frame Hobbit

Colin Ratcliff /

Gonna hit the joints with Ultra Copper RTV today and probably paint it some color. Not sure what right now.

First I need to clean up those ugly welds, though!

Re: Crazy Custom Frame Hobbit

You've come so far, I vote you throw that intake out and start from scratch. Sure, you can cap those little holes and start to tune it..but it will likely rattle itself apart anyways.

Moving to a spigot-style carb might be a good solution.

Re: Crazy Custom Frame Hobbit

Colin Ratcliff /

I know, but the welds are actually extremely solid on it - made sure that there was a ton of penetration and both pieces of metal were hot enough to melt it without the torch, so I'm actually pretty confident in it structurally, though time will tell!

Re: Crazy Custom Frame Hobbit

Dirty30 Dillon /

That intake despite fitting where you want it, is not going to do you any favors. All those 45* and 90*, along with the super long intake tract are going to hurt the performance of that very nice cylinder

Re: Crazy Custom Frame Hobbit

Colin Ratcliff /

I know, it's definitely a tough tradeoff. Particularly the bend at the bottom ends up being super tight. I think for now I'm going to go with this knowing that this will be a piece to improve over the winter, once I get everything else together and the bike running.

Re: Crazy Custom Frame Hobbit

Colin Ratcliff /

If nothing else I'll definitely shorten the tube that goes up. I'm thinking that I need to make a 3D model in SketchUp to figure out how to align this. There's a lot of stuff that's tough to clear, because the intake comes from the engine pointing slightly lower than horizontal, so to get it to go up you have to take a > 90* turn

Re: Crazy Custom Frame Hobbit

Tweaker trash /

Make a plate to adapt Malossi 4 petal reed block. If I’m correct is should for flat & use a puch intake.

Also I had this thought, you could run the drum brake on the pa50cvt and slip the belt and use it as a lunch lever 😮

Re: Crazy Custom Frame Hobbit

Dirty30 Dillon /

> Tweaker trash Wrote:

> -------------------------------------------------------

> Also I had this thought, you could run the drum brake on the pa50cvt and

> slip the belt and use it as a lunch lever 😮

The brake in the CVT works exactly like a brake in normal situations, it's just going to stop the bike.

That said, you could run both the rear drum and the trans drum for incredible braking with a cable splitter.

Re: Crazy Custom Frame Hobbit

Colin Ratcliff /

Joe S reached out and I'm gonna send the intake to him to get it remade right! While that's out I'm gonna get the water pump running and finish up the rest of the wiring. Also gonna get all the brakes set up.

Question for you guys, for the water pump, I can just reverse wiring if the flow direction is wrong, correct?

Re: Crazy Custom Frame Hobbit

Dirty30 Dillon /

> Colin Ratcliff Wrote:

> -------------------------------------------------------

> Question for you guys, for the water pump, I can just reverse wiring if

> the flow direction is wrong, correct?

Pumps are directional, even tho the majority will spin the other way with reverse polarity, the mechanism is designed to push efficiently in one way only.

Re: Crazy Custom Frame Hobbit

Colin Ratcliff /

Shoot, good to know. Trying to find out the direction this guy is supposed to go. Not seeing any documentation anywhere

Re: Crazy Custom Frame Hobbit

Colin Ratcliff /

Here's the diagram:

https://car-mod.com/img/schema/AU1268/160473.gif

Would love your thoughts

Re: Crazy Custom Frame Hobbit

Dirty30 Dillon /

Is that the VW pump? The one I have looks the same, and it is labelled on the pump what direction the pump rotates and what direction the flow goes.

Re: Crazy Custom Frame Hobbit

Colin Ratcliff /

Oh duh! Found it!

Re: Crazy Custom Frame Hobbit

This is why using a torch and brazing is betterer

It seals very easily.

But yeah just practice your welding and you could fix it yourself

Re: Crazy Custom Frame Hobbit

Colin Ratcliff /

oh yeah JBOT, this was brazing aluminum. I think it was just having some pinhole leaks

Re: Crazy Custom Frame Hobbit

Yeah aluminum brazing with zinc is prone to leaks. I could rarely seal anything with that stuff on cast aluminum

Re: Crazy Custom Frame Hobbit

Colin Ratcliff /

I'm super new to brazing, so stupid question warning:

when you're talking about brazing with a torch that seals easily, you're talking about brazing bronze/brass onto mild steel, correct? i.e., these guys:

https://www.amazon.com/dp/B000BO8WU0/

(edited)

Re: Crazy Custom Frame Hobbit

Yes. That’s standard brazing.

Silicon bronze. It’s great. I use it for gas tanks all the time.

Aluminum is super sensitive to any corrosion.

Steel not so much

Re: Crazy Custom Frame Hobbit

Colin Ratcliff /

Awesome. I need to shift the petcock on this tank so I'll get at brazing it - should be safer than welding!

Any advice on where to get a fitting for the tank? I'm going to be using an in-line fuel shutoff switch (because the petcocks on treatland seem to fail instantly), so I just need a mild steel fitting that I can crimp the fuel line onto

Re: Crazy Custom Frame Hobbit

Any steel tubing that’s thick enough is fine.

You do need mapp Gas or oxy acetylene for brazing this tho

Re: Crazy Custom Frame Hobbit

Definitely get an oxy set up if you don’t want it to look like you spilled liquid brass on everything. The heat isn’t concise enough with maap.

Re: Crazy Custom Frame Hobbit

Colin Ratcliff /

Oh dang good to know. I'll look into getting the oxy setup. Otherwise might just have to clean it up with the angle grinder after

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