Author Topic: Youre gonna hate me but another dual disc topic . possible for 33mm 350f? FOUND  (Read 684 times)

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Offline jamesv220820

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So I've been reading everything I can read on these dual discs and I'm hooked.
I wanna keep the stock look of the original forks. Could I just do the 550 hub, 18 inch aluminum wheels (to keep the weight down), and just use the 550 lower fork covers and keep all the rest of the 350f parts.

I'm guessing this is not possible but I would like to keep the chrome fork covers, painted fork covers , etc

It's either that or do the mc-again cb400f brembo kit
« Last Edit: June 07, 2016, 09:40:06 pm by jamesv220820 »
There is nothing to fear but fear itself . . . and trying to restore a cb350f

Offline camelman

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Why not just go to braided steel lines and a smaller master cylinder? The smaller master cylinder will yield much more pressure in the line, and hence more braking power. The stainless lines don't flex as much as the rubber lines, so you can push more pressure into them with the smaller master cylinder without the lever coming all the way to the handlebar.

I'm not familiar enough with the differences between the 350 and 550 hubs to know if they can be swapped.
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Offline Garage_guy_chris

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The parts for the most part are likely to be the same honda only had 3 brake calipers between 1969 and 1976.

From left to right: Early style finned 38mm caliper, Mid style Smooth 38mm, Late style 42mm



The problem i see with the 350F is the lack of the bosses on the right fork leg.... also the 350F uses 33mm fork legs rather than the 35mm the 500, 550, 750 uses... The only thing i can think of would be to swap the entire front end... 
1971 Cb450 Cafe  (on the road)
1974 Cb750 Restomod (on the road)

Offline calj737

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550 forks are 35mm. So I doubt the lowers would swap with the 33mm uppers. And a full fork swap would necessitate a change at the triples. If I understand your post...
'74 550 Build http://forums.sohc4.net/index.php?topic=126401.0
'73 500 Build http://forums.sohc4.net/index.php?topic=132935.0

*** Currently experiencing life at 60 WTFs per hour ***
I always thought getting old would take longer

Offline jamesv220820

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550 forks are 35mm. So I doubt the lowers would swap with the 33mm uppers. And a full fork swap would necessitate a change at the triples. If I understand your post...

You understand it correctly. I really don't wanna do a whole front end swap.

I guess I'll have to start thinking the path of the brembo upgrade kit.

http://japan.webike.net/products/21955602.html

It's not cheap but I'm sure it works. I wanted to do dual disc for more the asthetical look rather then the performance.

Also I already have stainless lines and a smaller brake up top. My breaking is very good but I want great. ( OCD mixed with ADD)
There is nothing to fear but fear itself . . . and trying to restore a cb350f

Offline calj737

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You probably can't get "great" brakes out of single piston calipers. Certainly not when compared to modern brakes. The heavier rotors, single pistons, and sheer mass will undermine your perception of them. But these are 40 year old bikes, so do bear that in mind.
'74 550 Build http://forums.sohc4.net/index.php?topic=126401.0
'73 500 Build http://forums.sohc4.net/index.php?topic=132935.0

*** Currently experiencing life at 60 WTFs per hour ***
I always thought getting old would take longer

Offline alacrity

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CAL:
It's not just the weight of the rotors but the nature of their construction. They are HARD, slick surfaced stainless steel.  I guess at the time Honda figured rust was the biggest enemy.  Mate that with squishy rubber brake lines, a mushy caliper piston seal and soft seals in the OEM master cylinder with a single 38 mm disc surface, and you can see why the result is... less than spectacular. It's really hard to get "bite" on these old rotors, and with all those flexing parts it's really hard to feel the amount of actual pressure being exerted on the rotor surface by the pads.  I guess this is why at a certain point they stopped making front brakes this way... 

My solution was going to a dual disk front setup to keep it looking as original to the period as possible, and drilling the disks to help cut down the unsprung weight.  And of course using steel braided lines throughout.

No one (unfortunately!) is making replacement rotors that allow more bite and better feel and do so with less weight. EBC has something for certain CB750s, so maybe they would step up if enough people asked?
I like the cb500/cb550 platform.  This is a place to share, learn and enjoy.  I am grateful to and for 99+% of this site's membership.

Offline calj737

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CAL:
It's not just the weight of the rotors but the nature of their construction. They are HARD, slick surfaced stainless steel. 
I'm aware of these things, thanks.
'74 550 Build http://forums.sohc4.net/index.php?topic=126401.0
'73 500 Build http://forums.sohc4.net/index.php?topic=132935.0

*** Currently experiencing life at 60 WTFs per hour ***
I always thought getting old would take longer

Offline jamesv220820

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Found them!
« Reply #8 on: June 07, 2016, 09:39:20 pm »
I found a company in Japan that makes 33mm dual disc fork lowers specifically for the CB350F/CB400F.  They also sell the corresponding dual disc wheel axel bolt and what not!



There is nothing to fear but fear itself . . . and trying to restore a cb350f

Offline silentsvn

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Re: Found them!
« Reply #9 on: June 08, 2016, 03:59:26 pm »
I found a company in Japan that makes 33mm dual disc fork lowers specifically for the CB350F/CB400F.  They also sell the corresponding dual disc wheel axel bolt and what not!

Do you want to share?
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Offline jamesv220820

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I found a company in Japan that makes 33mm dual disc fork lowers specifically for the CB350F/CB400F.  They also sell the corresponding dual disc wheel axel bolt and what not!

Do you want to share?

No...because then as soon as I share them everyone will buy them before I can find my expiration date on my card. lol.  I'm just kidding currently the company is out of stock. One of my friends who speaks fluent Japanesse will be talking with the company to see when they will be available.  For all we know they aren't making them anymore.  I hope that is not the case!  Will Keep everyone posted!

So here are the items they sell that you need for the kit

Replacement Axel bolt for dual disc mounting (MSRP $46.87)



Lower Forks. Obviously  (MSRP $330.00)





Speedo Cable with bend so it doesn't interfere with additional break (MSRP 30.00)



Slimmer speedo gauge retainer (MSRP $80.00)


Right side brake pipe (MSRP $12.00)


Longer Bolts for dual disc (MSRP $20.00)



Those are the parts they have (if in stock).  The obvious other parts you need are an additional brake line and dual banjo bolt.  Also the super obvious (additional caliper assembly, arm, & rotor.

You can switch out the master cylinder for the GL1000 just like the fellows do on the cb750's but the company also makes a bore kit for the original master cylinder (MSRP $94.00)




There I will let you know if they get back in stock.

-James



There is nothing to fear but fear itself . . . and trying to restore a cb350f

Offline jakec

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I would be nice if you could share the name of the company. I found aa company linked in another thread but it is all in japanese so I am having trouble navigating. And don't know how to find their products.

https://www.mc-again.com/technical.htm

1975 CB400F
1972 CL175 K2

Offline flybox1

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Its been over a year since the PO was active....might want to contact member Godffery, instead.
He's pretty good at the dual disk setups.  I got my drilled/thinned rotors from his store.
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Offline Don R

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 That speedo drive is beautiful but for the money I'd pursue cb550 parts. That's probably what those are.
If the things you own end up owning you, it's better to be owned by some cool things.

Offline jakec

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That speedo drive is beautiful but for the money I'd pursue cb550 parts. That's probably what those are.

What is the fix that people usually do to slim the drive retainer? I've seen a DIY version here on the forum before but can't find it now.
1975 CB400F
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Offline Don R

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 I guess those aren't 550 if they're 33mm. On my 750's Lester mags I cut down a speedo drive and pinned it to the wheel hub. 
If the things you own end up owning you, it's better to be owned by some cool things.

 

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