Disc Brakes on Older Murray?

[Ravenshurst]

I found an "older" Murray frame for an insanely low price....I haven't seen it yet, am going to go pick it up later today. All the pictures I have seen on the 'net appear to have diagonal dropouts. All of the disc brake adapters I can find appear to be for straight dropouts....
Does anyone know of an adapter that will allow me to install disc brakes on this frame? Thanks.

 

[Wildcat]

Here's a vid that goes through that. The disc hub width might be wider compared to the Murray frame, probably made for a coaster hub, but you can cold set the Murray frame for the wider hub. You have the disc wheels already? There are numerous adapters, I searched for mountain bike disc brake adapters and saw some, but I'm overseas, it might be a different result.

 

[Ravenshurst]

Hi Wildcat, thanks for the reply. Yes, I was chatting with a guy from BBS today, he told me their adapter won't work with my frame, but he sent me links to some that would. He also sent me a link to that video. The Murray was originally a six speed. The backstays(?) seem to be a little wider than I remember. I haven't measured yet, though.

No, I don't have wheels yet, and I am on a MacBook, so I have know idea how to show you a picture, but this is the ones I am going to o rder if you are curious. https://www.amazon.com/iMeshbean-Magnesium-Wheels-3-Spoke-Wheelset/dp/B079L55TPN.

 

[Wildcat]

When you said "Older Murray frame" I envisioned one of the classic cantilever frames they made for years. Pointy dropouts. But a 6 speed may be a newer style frame. That would make it easier to adapt to wider hubs and disc brakes, the rear portion is already wider for the 6 speed hub.

 

[MattiThundrrr]

Pretty sure that's the one they got, posted these in the other thread

It's a beauty!
https://ratrodbikes.com/forum/threads/raven.115796/#post-1211395

 

[Wildcat]

Who can keep up with all the threads? It's like answering all the happy birthday posts on FB. At least here it's worthwhile.

 

[MattiThundrrr]

I'm a little bit behind because of the Build Off, but I read every single post. And remember/retain at least 3 per day.

 

[Ravenshurst]

I can barely remember/retain my OWN posts.....
Mod......thanks for posting that picture.
Wildcat: Yes, I am hoping the mag & disc will kinda sorta slide right in....

 

[Starnger]

Just weld on a brake tab and don't forget to reinforce the frame
Otherwise i am not sure disc brake is really needed, bolt-on solutions have a lot of flex, so caliper brake would do as good.

 

[Ravenshurst]

Thanks for the reply, Starnger:
The frame has diagonal dropouts....
Unfortunately, I no longer have a shop. Normally, I would just farbicobble up whatever, cut to size, file to fit, weld, paint to match.....I moved into this tiny little place, so I am working with a bolt on/home made solution. The rims don't accept rim brakes, and, in all honesty, I MUST HAVE those rims, lol. I am getting there, I think....

 

[Indyjps]

Watched the video, looks like the universal disc caliper mount fits nothing as a direct bolt on.

BUT. It is a disc caliper mount. May be worth getting one. Line it up, don't use the sheetmetal plate. Look for overlap on the disc caliper mount and your drop outs to drill thru both and bolt it on.

 

[kissmyklunker]

I have disc brakes on my mountain bikes and they truly are awesome. Hydraulic on one and cable pull on the other. I actually prefer the cable pull type just for simplicity. I've bled the hydraulic set, and short of buying a bleeder kit, no big deal. But the cable pull can be adjusted anywhere.

I have an aluminum frame that came with 3 speed coaster and was trying to put a freewheel on it. With no caliper mounts, I didnt have a lot of choice so bought one of the disc brake adapters, cause it was cheap. Some of them are outright pricey, but same result either way.

Its thin and bendy and fits nothing. total waste of money. I put the coaster back on the bike.

But it got me more determined than ever to mount a disc brake on a bike that didnt come stock with one. I ended up adding one to a beater 20 inch frame I had. By the way its no longer a beater, maybe a rat rod tho ;-)
This pic was just after first assembly. I purchased a weld on tab from a bike tube supplier. a flip flop hub with a rotor adapter on one side, a 160mm rotor and a scavenged TRP Spyke cable disc brake.
From what I hear I wouldnt attempt welding an aluminum frame.

Assemble the wheel and rotor and bolt it in the frame. bolt the weld on tab to the disc brake and position the brake on the rotor where you want it making sure there is clearance and a bit of adjustment side to side. tack weld the tab on the frame.
Disassemble and weld that tab solid. reassemble and adjust.

I may braze or weld some cable mounts under the top tube for the gyro cable, but it stays there with zipties for now.

Did I say I love disc brakes?

 

[MattiThundrrr]

Thanks for the explanation, I saw when you posted that Haro elsewhere, was wondering about the brake setup. My inner retro grouch is resistant to disk brakes on BMXs, but I'm trying to get over it. To me, they don't seem necessary for a track bike, but I suppose they could come in handy for street riding.

 

[kissmyklunker]

I like it cause it doesnt take off the paint/anodizing on the rim. Stops way faster than most calipers, easier to adjust and maintain. I'm gonna try it at the bike park this weekend. I'm not one for running with no brakes and using foot to stop.

 

[Ravenshurst]

Indy and kissmyklunker...Thanks. I will probably wind up just making a tab and welding it on. I bought the adapter, thinking I could use it as a template. I have tons of steel around....