Fitting Twin Discs to a 74 Police Eldorado

[Plainjs]

Hello everyone

74 Eldorado was designed for twin Discs but came with only one, i’m trying to figure out what i need to fit new 300mm EBC “Pro Lite” rotors.
There is a rotor “carrier” holding the original (right side) disc in place and I believe the new EBC can be swapped out with no adjustments required, input appreciated.
The other side (left) has no rotor and no carrier mounted to the wheel hub to fit one to.
It is not clear if the same carrier used on the right side will provide the required offset to properly align new rotor with a F 08 caliper, again, insight much appreciated.
Sourcing correct carrier ( plus extra spaces if needed) much appreciated.

Thanks in advance

I KNOW this subject has been covered before somewhere , I just cant find it!!!

..john

 

[Amboman]

Usually what is required is either the correct 39.5 mm thick bearing/disc carrier (same as on the right) or a custom-made 17.5 mm thick spacer in addition to the present 22 mm thick bearing carrier. Cycle Garden sells the 39.5 thick bearing carrier (search seller "moeguzzi" on ebay) but it's around $250. Used ones are very rarely found.

About a year ago I had a batch of 17.5 mm spacers made, but all were pre-sold and I have no plans to make any more. Any good machine shop should be able to make one using the dimensions supplied here: http://thisoldtractor.com/moto_guzz..._flange___bearing_carrier___disc_carrier.html

There is more information on the same website that you might find useful as well.
http://thisoldtractor.com/moto_guzz...l_information_about_adding_a_second_disc.html
http://thisoldtractor.com/moto_guzzi_loopframe_disc_brake_floating_rotors.html

 

[Plainjs]

Usually what is required is either the correct 39.5 mm thick bearing/disc carrier (same as on the right) or a custom-made 17.5 mm thick spacer in addition to the present 22 mm thick bearing carrier. Cycle Garden sells the 39.5 thick bearing carrier (search seller "moeguzzi" on ebay) but it's around $250. Used ones are very rarely found.

About a year ago I had a batch of 17.5 mm spacers made, but all were pre-sold and I have no plans to make any more. Any good machine shop should be able to make one using the dimensions supplied here: http://thisoldtractor.com/moto_guzz..._flange___bearing_carrier___disc_carrier.html

There is more information on the same website that you might find useful as well.
http://thisoldtractor.com/moto_guzz...l_information_about_adding_a_second_disc.html
http://thisoldtractor.com/moto_guzzi_loopframe_disc_brake_floating_rotors.html

Thanks Amboman, I believe I understand the carrier issue now.

In a comment you attached Charley Cole said not to use F08 calipers with EBC rotors or a catastrophic lock up would occur as the piston over extends due to the thinner rotor (EBC is 5mm and I measured stock at 6.5mm),
Obviously this got my full attention as this is exactly what I was intending doing. Is there a way for me to get in touch with Charley Cole?

Thanks

 

[Amboman]

Thanks Amboman, I believe I understand the carrier issue now.

In a comment you attached Charley Cole said not to use F08 calipers with EBC rotors or a catastrophic lock up would occur as the piston over extends due to the thinner rotor (EBC is 5mm and I measured stock at 6.5mm),
Obviously this got my full attention as this is exactly what I was intending doing. Is there a way for me to get in touch with Charley Cole?

Thanks

Unfortunately, Charley Cole was very ill and there are (unsubstantiated) reports of his passing. I haven't been able to contact him for years.

In any case, it has been determined that the 5 mm rotor was actually meant for something other than a Guzzi (Laverda IIRC) and those supplied by EBC meant for older Guzzis are thicker. Still not quite as thick as the o.e. Brembo rotors though. But, there are quite a few "Loopers" running the EBC rotors and F08 calipers and none have experienced any issues. I've installed a few myself and have carefully checked to make sure there would be no problems.

 

[Plainjs]

Unfortunately, Charley Cole was very ill and there are (unsubstantiated) reports of his passing. I haven't been able to contact him for years.

In any case, it has been determined that the 5 mm rotor was actually meant for something other than a Guzzi (Laverda IIRC) and those supplied by EBC meant for older Guzzis are thicker. Still not quite as thick as the o.e. Brembo rotors though. But, there are quite a few "Loopers" running the EBC rotors and F08 calipers and none have experienced any issues. I've installed a few myself and have carefully checked to make sure there would be no problems.

Thanks Amboman, I found a phone number for Charley Cole and tried calling him but only got a ladies message that her and Charlie were not home so to leave a message, which i did but have not received a call back.
His comment was pretty explicit that there WOULD be catastrophic failure if these rotors were used with F08 calipers, he did indicate there was a work around for a skilled mechanic/machinist, would you know what his precise concern was?

Thanks

 

[Amboman]

Like it says in the link: The pistons on FO8s cannot extend far enough out of the body of the caliper to come in contact with a 5 mm rotor and then safely retract once you have even a little wear on your brake pads. After very little use, they will extend, contact your rotor, not retract and lock your brakes.

And as I posted above, the rotors he was talking about were not made for a Guzzi originally, but for a Laverda. When using the EBC discs made for our Guzzis, there have been zero issues.

 

[Plainjs]

Hello Amboman, with all due respect and I mean that sincerely but the caliper does not know whether it’s a disc made for a Laverda or a pretty new EBC floater.

The issue was said to be that when F08 piston extended onto a 5mm disc it WOULD lock the front wheel, in all probability this WOULD occur with maximum hand pressure and be shortly followed by a fast, probably fatal flight through the air all the while thinking “why didn’t I listen to Charley fucking Cole.

If I understand correctly using the 5mm EBC rotor is exactly what Charley Cole was warning about. That a catastrophic failure has not happened YET is encouraging but if Charley was onto something I can’t just install EBC rotors and hope for the best, I got to dig deeper.
I wonder if EBC would have input on this?
Has anyone dealt with their customer service, wait a second, what about BREMBO, why would they NOT know the answer to whether an F08 can be used with a 5mm disc!
Thanks Amboman I will let you know how I get on!
John

 

[john zibell]

BMW air heads use the F08 caliper. Folks have been installing EBC rotors for years. No issues. I suspect Charlie's experience was a one off.

 

[Amboman]

As I explained earlier, the Laverda discs are thinner than those sold specifically for our Guzzis: "In any case, it has been determined that the 5 mm rotor was actually meant for something other than a Guzzi (Laverda IIRC) and those supplied by EBC meant for older Guzzis are thicker."

 

[Plainjs]

Gentlemen

I finally figured it out, we are actually talking at cross purposes.
My questions were about the EBC Pro Lite 300mm with Floating Rotors, sold by MG Cycle (part # MGEBC300) the description states pretty clearly they CAN be used on my 74 Eldorado but when I received them and measured them at 5mm, Charlie’s comment on TOT came to mind and worried me.

I just looked again at the MGCYCLE web site and they do have a non floater that is 6.5 mm thick, I assume this is the unit you were talking about.

Thanks for your patience and letting me pick your brains while I sort this out. I will be contacting MGCycle.

John
Ps. I still want to use a floating disc, if it’s practical maybe I can split the F08 and shave each face a little.

“It ain’t f..... up until you can’t fix it”

in their blurb

Like it says in the link: The pistons on FO8s cannot extend far enough out of the body of the caliper to come in contact with a 5 mm rotor and then safely retract once you have even a little wear on your brake pads. After very little use, they will extend, contact your rotor, not retract and lock your brakes.

And as I posted above, the rotors he was talking about were not made for a Guzzi originally, but for a Laverda. When using the EBC discs made for

As I explained earlier, the Laverda discs are thinner than those sold specifically for our Guzzis: "In any case, it has been determined that the 5 mm rotor was actually meant for something other than a Guzzi (Laverda IIRC) and those supplied by EBC meant for older Guzzis are thicker."

Ambom
our Guzzis, there have been zero issues.

As I explained earlier, the Laverda discs are thinner than those sold specifically for our Guzzis: "In any case, it has been determined that the 5 mm rotor was actually meant for something other than a Guzzi (Laverda IIRC) and those supplied by EBC meant for older Guzzis are thicker."

 

[Amboman]

As much as I respect Charley Cole, sometimes he is/was a bit of an "alarmist" on certain subjects. Dozens of Guzzi owners have been using the EBC Pro Lite rotors on their older Guzzis (with F08 calipers) for years and none have reported having any issues at all, much less anything as dire as what Charley warns about.

 

[Plainjs]

hi Amboman
I had previously contacted BREMBO (USA) and finally got the official answer I was looking for, this was their response.

I have done some more research and spoke with Brembo Italy and with the more recent F08 calipers there should no issue with the 5mm rotor. As always the finale fitment should be double checked on any motorcycle that is getting different brakes installed.

Thank you,
Nicole Lavash, Senior Account
Manager

Motorcycle Program