Topic: 1974 Honda CB 750 advice

[Tafster]

Hello all,
I have a 1974 Honda CB 750 which I want to modify. My first modification will be to convert to twin disks on the front. I don't want to use a modern, radial type style of braking system like GSX, CBR, etc. I want to keep it looking relatively retro, therefore axial mounted calipers. I also don't ride in the style that would warrant sportbike performance-orientated braking systems.
It seems as if my current forks look as if a second caliper could be mounted but whether or not there is enough clearance or maybe the hub wouldn't work, I'm not sure? I've upgraded brakes before but mainly on modern bikes, never older ones.
If I have to completely replace the front end, is there anything that will work? I appreciate that I might have to modify the stem and bearings. I probably need to pay attention to wheel size and rake/trail as well? I would prefer to run spoked wheels also.
If anyone could direct me towards some detailed advice or companies that could help, I would greatly appreciate it.
Cheers.

[Stev-o]

Welcome Tafster.  A common brake upgrade on our 750's uses the the GL [Goldwing] front end.
They are easy to find and reasonable.  My buddy did one on his bike a few years ago.

Here is some more info...

http://forums.sohc4.net/index.php/topic,171672.msg1998114.html#msg1998114

[Tafster]

I had heard the 75/6 Goldwing would work, I was just concerned about what effect the increased rake and trail would mean. I assume it will be a little bit more difficult to turn but more stable at higher speeds?

[bryanj]

There are loads of write ups on how to twin disc a 750 depends on type of caliper bracet you have

[seanbarney41]

Hi Tafster
Please don't think I did not try to anwer your pm.  I had a lengthy answer all typed out and went to send and your inbox was full, as you are a new member with a low post count.  Your inbox storage capacity will increase once you have a certain amount of posts.

As other members have posted, you have at least 3 paths to travel in order to improve brakes and still meet your required criteria...

-add a second rotor and caliper to the stock forks...not as totally "bolt on" as it would seem but can and has been done countless times.  Plenty of threads here on how to do it.  I have done it and I believe it is the best improvement as far as dollar amount per amount of gain.

-swap a 75-77 gl1000 front end...imo, forks will require modification (shorter plus new correct strength springs and valving)to maintain good handling and rebuild of gl brake components is relatively expensive.  I have done this and the results can be very good, but it is an expensive way to go.

-optimize the stock system....so much can be done to improve what is already there.  Drilled rotor, better pad compound, braided brake lines, different mc and relentless maintenance can result in dramatic improvements.

-Member Scottly has worked out a way to use cb750f2 forks with a spoked wheel hub.  The stock f2 brakes are better than any of the above and with the availability of bolt on 4 piston calipers from several 1980's Honda's, this could be "the" front end swap.

-bound to be more right side up fork options out there, but the hard part is getting that spoked wheel to play nice.  No telling what could be done with a mill, lathe, and some enginuity...

[Bankerdanny]

I have an 750 F2 front end swapped onto my wire wheel '76 F1 (although I have aftermarket alloys rather than the stock spoked wheels). The swap is pretty straight forward.

You can buy a complete kit from Godffery's garage to add the 2nd disk to your bike that uses the same front mounted/pivoting bracket style as your bike has now. You could assemble your own more cheaply, but if you have the cash and don't want to worry about getting the setup right, it's a good option. Plus Jeff, the owner, is a good guy (I've been to his shop and bought some of his stuff) and also a member here. https://godfferysgarage.com/

[754]

 Bad part about adding 2nd disc to stock fork.. heavy rotors, but it can work well even with stock mc.
 And very hard to mount other calipers to.
 What Scottly and I did was use bigger floating, lighter rotors to the stock 6 bolt hub, and making new caliper mounts.
 I am getting a single big rotor with better caliper would work very well, but far easier to do to F forks than K forks.

[Stev-o]

I also don't ride in the style that would warrant sportbike performance-orientated braking systems.

If you have a stock motor and dont ride "in that style" why do you feel the need to upgrade?

[754]

I don't mind being able to stop,  right now my 750 does not do that well. .

I have Kawi ZX 43mm  fork I may use, floating big discs, 4 piston caliper..  I may put that on.. it will stop..

[Tafster]

Purely for aesthetics and my OCD is hell when there is no symmetry 

I also don't ride in the style that would warrant sportbike performance-orientated braking systems.

If you have a stock motor and dont ride "in that style" why do you feel the need to upgrade?

[Tafster]

No problem, appreciate the response

Hi Tafster
Please don't think I did not try to anwer your pm.  I had a lengthy answer all typed out and went to send and your inbox was full, as you are a new member with a low post count.  Your inbox storage capacity will increase once you have a certain amount of posts.

As other members have posted, you have at least 3 paths to travel in order to improve brakes and still meet your required criteria...

-add a second rotor and caliper to the stock forks...not as totally "bolt on" as it would seem but can and has been done countless times.  Plenty of threads here on how to do it.  I have done it and I believe it is the best improvement as far as dollar amount per amount of gain.

-swap a 75-77 gl1000 front end...imo, forks will require modification (shorter plus new correct strength springs and valving)to maintain good handling and rebuild of gl brake components is relatively expensive.  I have done this and the results can be very good, but it is an expensive way to go.

-optimize the stock system....so much can be done to improve what is already there.  Drilled rotor, better pad compound, braided brake lines, different mc and relentless maintenance can result in dramatic improvements.

-Member Scottly has worked out a way to use cb750f2 forks with a spoked wheel hub.  The stock f2 brakes are better than any of the above and with the availability of bolt on 4 piston calipers from several 1980's Honda's, this could be "the" front end swap.

-bound to be more right side up fork options out there, but the hard part is getting that spoked wheel to play nice.  No telling what could be done with a mill, lathe, and some enginuity...

[Tafster]

I did hear about this guy and sent an email to him last night. I'd prefer to utilize what I have rather than completely change. Cost isn't necessarily an issue, it just has to look right.

I have an 750 F2 front end swapped onto my wire wheel '76 F1 (although I have aftermarket alloys rather than the stock spoked wheels). The swap is pretty straight forward.

You can buy a complete kit from Godffery's garage to add the 2nd disk to your bike that uses the same front mounted/pivoting bracket style as your bike has now. You could assemble your own more cheaply, but if you have the cash and don't want to worry about getting the setup right, it's a good option. Plus Jeff, the owner, is a good guy (I've been to his shop and bought some of his stuff) and also a member here. https://godfferysgarage.com/

[Tafster]

I guess cross drilling the rotors would help a litttle?

Bad part about adding 2nd disc to stock fork.. heavy rotors, but it can work well even with stock mc.
 And very hard to mount other calipers to.
 What Scottly and I did was use bigger floating, lighter rotors to the stock 6 bolt hub, and making new caliper mounts.
 I am getting a single big rotor with better caliper would work very well, but far easier to do to F forks than K forks.

[Bankerdanny]

I guess cross drilling the rotors would help a litttle?

it does, although not completely. Another service that Godffery's offers is thinning and drilling. I have his modified rotors on my current 750F and also had one on my 550F I sold a couple years ago. I haven't weighed them, but I would bet that two thinned and drilled rotors doesn't weigh that much more than a single unmodified rotor.

[Tafster]

I did call him on 262-210-9269 but it said it was disconnected? Do you please have a different number for him?

I guess cross drilling the rotors would help a litttle?

it does, although not completely. Another service that Godffery's offers is thinning and drilling. I have his modified rotors on my current 750F and also had one on my 550F I sold a couple years ago. I haven't weighed them, but I would bet that two thinned and drilled rotors doesn't weigh that much more than a single unmodified rotor.

[low-side]

I added a second disc and rotor to my '75.  Amazing improvement, especially after swapping in a GL1000 master cylinder and braided lines.  You end up with more brake than tire and it looks period.  GL1000 swap looks period as well.  Add in a fork brace and some cartridge emulators and you'll feel like you bought a different machine.

[PeWe]

I added a 2nd rotor on my CB750 K6 and suddenly my bike has working brakes!

Stock calipers and DSS aftermarket rotors that look like stock. I like the stock not drilled look
DSS MC.
DSS complete caliper.


"Only" stock engine, a new better rotor and good pads. DSS claim that their rotor is better due to the material. Add one more if not enough.

Dual brakes cause extra work when removing front wheel. The right caliper with bracket must go off before wheel can.

[Bankerdanny]

I did call him on 262-210-9269 but it said it was disconnected? Do you please have a different number for him?

I guess cross drilling the rotors would help a litttle?

it does, although not completely. Another service that Godffery's offers is thinning and drilling. I have his modified rotors on my current 750F and also had one on my 550F I sold a couple years ago. I haven't weighed them, but I would bet that two thinned and drilled rotors doesn't weigh that much more than a single unmodified rotor.

Send him a PM through the forum. That is how I ususaly reach out to him.

[PeWe]

About dual brakes.
The right caliper holder need to align with the rotor.
2x 5mm spacers on the top M6

1 x 5mm spaver on the lower M8. (6.5-7mm should be better)

I had to add an extra washer to the lower spacer since the fender work as spacer on the M6 screws.

Note how the fender and caliper holder sit.

Left original has Fork- holder-Fender.
Right using stock holder:
Fork- fender- spacer- caliper holder

I guess no spacers if using a caliper holder made for right side with correct bend. I have heard that it has been one made.
Note!
The adj srew with spring is longer, bolts for rotors too and the stuff for speedo gear different too.

Andy Cepok in Germany Motorradteile at eBay sell kit with rotor bolts, speedo gear adapter and  adj screw with spring.

[slikwilli420]

Not really budget, but very period and far better than OEM calipers is to use the GL1000 forks with a period caliper like AP, Brembo, etc and match the master cylinder to the task. I have the GL forks on my race bike and with 14.25" shocks out back the bike has the correct trail to hand well. I did not change the length of the forks, simple run a different triple clamp that holds them a little higher up relative to the top of the steering neck. Its a very worthwhile upgrade over the mediocre at best stock swinging calipers.

[Don R]

 I did a double disc setup on a 76F and loved it. I left the stock M/C and it had more travel but great lever feel. I scalloped an older  front tire practicing panic stops. I drilled the rotors and left the stock pads after scuffing the surfaces of them.

[Tafster]

Well, I called Godfrey today and ordered his kit so I'll be stripping the bike down hopefully this weekend. I will probably start a new build thread, assuming anyone is interested, documenting the customization of my bike. I'd like to thank everyone for their help, opinions, and advice; I'd be absolutely screwed without you all.

I did call him on 262-210-9269 but it said it was disconnected? Do you please have a different number for him?

I guess cross drilling the rotors would help a litttle?

it does, although not completely. Another service that Godffery's offers is thinning and drilling. I have his modified rotors on my current 750F and also had one on my 550F I sold a couple years ago. I haven't weighed them, but I would bet that two thinned and drilled rotors doesn't weigh that much more than a single unmodified rotor.

Send him a PM through the forum. That is how I ususaly reach out to him.

[tlbranth]

I have a '70 CB750 and a '75 GL1000 and the CB brakes are waaaaay better than the GL. Unless your goal is pimping, leave the brakes alone. I've never had a problem with My CB750 brakes.

[754]

 I think a lot if today pads, dont perform as well as the originals. 

[PeWe]

Better with the asbestos stuff. Heard from a car repair guy.

[Doobie]

Upgrade to a lighter, floating rotor -- very good bang for buck. EBC makes one for vintage bikes.

[Stev-o]

I will probably start a new build thread, assuming anyone is interested, documenting the customization of my bike.

Yes, start a thread in the project shop section. We'll follow along and answer any questions you may have.

[Tafster]

I'll be starting a thread called "100$ Honda"

I will probably start a new build thread, assuming anyone is interested, documenting the customization of my bike.

Yes, start a thread in the project shop section. We'll follow along and answer any questions you may have.

[bert96]

I did this,maybe you'll like it.

Bert

[Tafster]

Looks very nice indeed but the calipers look a little modern for my plans. Thanks for posting though.

I did this,maybe you'll like it.

Bert