brake rotors

ace787 · April 13, 2020, 05:59:50 AM

77 rd400 using stock calipers, what are the options for brake rotors? I know about Economy and HVC, but was wondering if other models will fit

suey1958 · April 13, 2020, 06:36:15 AM

I'm guessing that you are looking for drilled rotors?

Dvsrd · April 13, 2020, 07:34:20 AM

Also, are you looking for floating discs, or non-floating? For a real "sleeper" setup, have a look at getting a drilled, 5 mm thick disc for the stock carrier, made by ISR in Sweden. Their disc material is top notch. You would need to order a disc made to your spec, using the ISR order form. www.isrbrakes.se

SUPERTUNE · April 13, 2020, 10:47:31 AM

EBC replacement...

https://www.ebay.com/itm/NEW-EBC-MD2025RS-Replacement-OE-Rotor/164026975981?fits=Model%3ARD400%7CMake%3AYamaha&epid=171208062&hash=item2630c506ed:g:e5kAAOSwoQleWA9j

Chuck

Tuck · April 13, 2020, 01:56:41 PM

+1 on the EBC's

ace787 · April 13, 2020, 04:41:00 PM

yep looking for drilled rotors. Chuck, that link is one for a Daytona. Will that fit a 77 ? Or is there a another number for 76-78 ?

SUPERTUNE · April 13, 2020, 11:13:42 PM

I don't think they list one for a '76-'78, as they used a thicker rotors than did the Daytona stock rotor. but they are a direct bolt on.
When we raced our historic production RD250 racer we used stock Daytona disk on the front as we were allowed to update and back date stock oem parts. Lost some added weight to help that little 250 engine.
C

RDFL · April 13, 2020, 11:34:46 PM

Quote from: Tuck on April 13, 2020, 01:56:41 PM
+1 on the EBC's

Looks great, very clean.

ace787 · April 14, 2020, 06:06:33 AM

thanks chuck, I think I'm gonna give that a try for the front...maybe the back also

SUPERTUNE · April 14, 2020, 10:44:28 AM

That Ebay listing is the wrong pic also...
Tucks is right...
And found it on Amazon too.

https://www.amazon.com/EBC-Brakes-MD2025RS-Brake-Rotor/dp/B0073DVOUW

95bravo · April 19, 2020, 01:48:11 PM

Double thanks to Chuck and Tuck for the info. Good to know about the bolt on replacement. A drilled rotor is on my to do list and this info is helpful when I get to it.

IR8D8R · April 22, 2020, 03:22:29 PM

Guys,
What's the "best" upgrade to make on the front brakes of RD 350's? I've seen the drilled OEM rotors people are selling but I'm not sure if that is the appropriate first solution.

I always preferred modifications to my vehicles that are somewhat period in appearance. I think I am going away from that with my cafe bike in favor of modernizing mechanicals as long as it doesn't look totally out of place. ...That's what people say right before they waste a bunch of money they will never get back.

For a minute I decided I would do a conversion to dual-disc setup from a TX500. Until people reminded me that it added more weight than benefit. It looks pretty savage IMO but I think in retrospect that the experts are correct about the dubious value of it.

I'd love to do a floating rotor like these. I have seen plenty of bikes that have had caliper adapters fabricated. I recall Mark posted some adapter designs that could be made up at a machine shop. The design uses calipers from a newer bike I think. Does anyone have a list of the exact items required for a conversion? Spacers, adapters, caliper, and rotor that play together... I'm not sure that all these things have been listed together on a single post.

IR8D8R

Hawaii-Mike · April 22, 2020, 05:37:18 PM

The small tire size of an RD350 or RD400 may limit the ability of the bike to brake even with a dual disc setup. It might get too easy to lockup the brake.

rodneya · April 22, 2020, 05:47:32 PM

Quote from: IR8D8R on April 22, 2020, 03:22:29 PM
Guys,
What's the "best" upgrade to make on the front brakes of RD 350's? I've seen the drilled OEM rotors people are selling but I'm not sure if that is the appropriate first solution.

I always preferred modifications to my vehicles that are somewhat period in appearance. I think I am going away from that with my cafe bike in favor of modernizing mechanicals as long as it doesn't look totally out of place. ...That's what people say right before they waste a bunch of money they will never get back.

For a minute I decided I would do a conversion to dual-disc setup from a TX500. Until people reminded me that it added more weight than benefit. It looks pretty savage IMO but I think in retrospect that the experts are correct about the dubious value of it.

I have dual 310mm disks on the front of my 73 RD350 with a Cognito moto hub and I have not noticed any issues other than having to go easy on the front brake as the stopping power is ridiculous.

Dvsrd · April 23, 2020, 06:14:00 AM

Quote from: IR8D8R on April 22, 2020, 03:22:29 PM
Guys,
What's the "best" upgrade to make on the front brakes of RD 350's? I've seen the drilled OEM rotors people are selling but I'm not sure if that is the appropriate first solution.

I always preferred modifications to my vehicles that are somewhat period in appearance. I think I am going away from that with my cafe bike in favor of modernizing mechanicals as long as it doesn't look totally out of place. ...That's what people say right before they waste a bunch of money they will never get back.

For a minute I decided I would do a conversion to dual-disc setup from a TX500. Until people reminded me that it added more weight than benefit. It looks pretty savage IMO but I think in retrospect that the experts are correct about the dubious value of it.

I'd love to do a floating rotor like these. I have seen plenty of bikes that have had caliper adapters fabricated. I recall Mark posted some adapter designs that could be made up at a machine shop. The design uses calipers from a newer bike I think. Does anyone have a list of the exact items required for a conversion? Spacers, adapters, caliper, and rotor that play together... I'm not sure that all these things have been listed together on a single post.

IR8D8R

First priority would be good pads
Second would be a new, braided single piece hose.
Third (actually more a second as well) is a smaller master cylinder with brake light switch. I use a 13 mm Brembo with a rectangular reservoir
If this is not enough, you can look at various disc options. Personally, I would consider thinning the stock disc, from 7 to 6 or 5 mm thickness.
The ultimate "stock looking" disc would be the 298 mm disc from a 73-76 TX/XS650. They have a carrier that looks just like the RD350 one, just 31 mm larger in diameter. This setup would still use the RD caliper, but requires the fork sliders from the 650 as well. I have all the parts for this, but I haven't got around to it yet. Among other things, the 650 sliiders are thicker and heavier, so I plan on machining them down to 350 dimensions.

News:

brake rotors