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Discussion Starter #1
Hi guys,

I'm new to the forum. I have a CB350F (disk front) and would like to change out the forks for something more modern. What is the process here? I'd like newer forks with clip on bars etc (more cafe style) What forks are interchangable with the CB350F? What is the process re break calipers on newer forks...are all the fitings standard?

Thanks

Izzy
 

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hey izzy. welcome.

i think im not going to be the only one to go here. it sounds to me, at least from the naivity of your question, that youre not an experienced rider or mechanic. i mean, maybe you are one or the other, but not both im guessing.

so, from this, i am going to make 2 huge assumptions.

1. if you had newer better forks, you actually wouldnt be able to utilize them without tossing the thing into the weeds.

2. if you do begin this project not knowing what youre doing, you will have a never ending string of "how do i....." questions that we have all covered here before.

i will spare you my complete asshole attitude by giving you the following tips.
this list will apply to everyone who is new here.

first, get a decent set of tools. more than pliers, an adjustable wrench, and a hammer. youll need combination wrenches and a set of sockets. deep and shallow. get an impact driver. a basic hammer type will work for now. a hammer. a plastic/hyde/brass hammer or deadblow hammer. you'll need a couple of philips screw drivers. the nicer the better. and most importantly, get a book that covers maintenance of your specific bike. a clymer manual, a factory one is better. whatever. a wood box, a lift, some jackstands, somethng to support your bike while youre working on it.

the books will walk you through about 98% of everything you'll need to know. anything you get lost on, feel free to ask here.

as far as forks go, your question is so vague, its almost impossile to answer. are you talking about cbr1000 forks, or 70's cb750 forks? most likely, if youre going to swap a disk front with a spoked wheel for the same, you should consider swapping an entire front end. from a 500/550/or 750. just my opinion. if youre going to put clipons on it, you will have to figure out cable and wire routing, master cyl location, brake hoses, headlight mounts, gas tank clearance and multiple other issues. its not just a simple swap. it can be difficult to just find a clean set of forks. much less ones that have good seals, arent bent, etc...

if youre not outriding your suspension now, (translate, if youre a squid) i wouldnt bother. you probably wont notice a huge difference other than it handles like a 72 fleetwood in parking lots and makes your back stiff. learn to ride the thing first. before you decide youre going to be geoff duke. (google his name) it wont be as cool in front of starbucks, but it will be well worth your while.



now call me an asshole, and let the flaming begin.

jc
 

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You're a very mean man. Don't read fuzzybutt's "new bike" thread.
 

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the difference, in text, from fuzzbutt, and izzy is fuzzbutt seems to have an idea. he has interesting ideas and more than just one post. im not dissing izzy, not at all. but lets just say that swapping a front end requires more than just a bunch of guys on a bulletin board telling you what to do. you need some tools, some knowledge of how it all works, and i think most importantly, a little experience with motorcycle mechanics. we've all seen the hipster with the coifed hair and arai, and $1500 jacket. they can buy a nice bike, but dont know how to gap a set of points. and please, dont get me wrong, i am not assuming izzy is any of those things. im just making the point that there can be a fair amount of work involved, and if you dont know what youre doing, it can be a major pain in the ass, not to mention dangerous. lets not forget here that you are taking apart the front of your motorcycle. at 70mph down the highway, you dont want to realize "uh oh, i forgot to tighten that bolt". i take this from the vague way the question was posted. i dont think its unfair to jump to the conclusion this person may not know alot. nor do i thnk its unfair or unhelpful to say get some good tools before you try riping apart the front end of your motorcycle.

so if youre unfamiliar with how your bike handles and works, for now, you might be better off learing how to ride it, doing basic work, and leave making it into a manx for later.

of course, if i am waay off base here, i will take the beating.

also, i have a very close friend, who does coif his hair, who drives a bmw 3 wagon, who designs websites, and wears a really nice helmet. (no, not aaron) hes the last person i would have ever thought would tear into a cb500/4 motor and pull pistons and rebore and want to rebuild it. but hes done alot of shit on his bike that i think is great. and hes learning a ton. so im not saying anyone cant do it. im just putting out there that you need some basics before you try something like swapping a front end. just be sure youre ready to tackle a project like that. it can be bigger than you think.

nothing against you izzy.

jc



Edited by - joe c on Feb 07 2007 10:37:37 PM
 

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I know where Joe is coming from. Sometimes you see a question that to answer properly for an inexperience wrench would take several pages or more.

To attempt to make a short answer....if you just want a decent more modern front end....swap in something like a VTR250 front end. They are 35mm, single disk brake, air-fitting on top, semi-modern type fork.
If you are new to this type of thing....shoot for an entire front end so all you have to do is adapt the steering stem to fit the 350, rather than sorting out caliper mounts, disks mounts etc etc. Hydraulic brake line fittings are fairly standard from one Honda to another Honda...but line length, bends and junctions might be different. If swapping calipers...mounts might be different, spacing different, disk size different.

And bear in mind...you have things like fork offset and trail to take into consideration...you could screw up the handling.

Just a lot of if's and maybe's.
JohnnyB
 

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im guessing the cb350f doesnt have 35mm forks.

thanks jb

jc
 

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Joe...I love you

If you want modern buy a modern bike. If you knew anything about bikes you wouldn't have bought a 350Four in the first place (and don't use that it was cheap excuse - I've paid some rediculously low prices for bikes that were decent)

If you are new to this, just get the bike running perfect, and I mean flawlessly perfect before you begin hacking away. chances are you'll find that the japanese engineers actually knew what they were doing when they designed the bike to be a street bike and that all those years dominating the marketplace were not just hype. If were were talking about a notoriously overpowered bike (early cb750, kawi triple, gs1100) then maybe fork and brake upgrades would be in order but it is a freaking 350four for gods sakes, they can't even get out of their own way.

The cb350F has the same disc front end the 350 twins had in their last year of production. Honestly the bike will probably never go fast enough for you to need the modern forks (the 350 four is a viciously slow lump).

You want to make a cafe bike strip the sucker down to the rolling chassis (with engine) and then just put back the bare essentials of what you need to make a running bike.

Anyway, joe alread said all the mean stuff I was going to say so I'll just give you this advice: planning goes a long way - and if you sit down and figure out what your goals are and how to accomplish them you'll soon find out what is really possible and worth it to mod on a cb350four, and then you can break down your questions as to how do I address this particular problem, etc.


NOTICE TO ALL NEWBIES: if you come in here with an uber general question like this about a hard subject and you give no info about your bike other than the year and the model expect your head to be put on a pike. I want to paragraphs people, long explaniations, pictures - the works. Gotta know why you want to do this, what is bad on your bike, what your background is, what kind of resources you have available....you get the picture.

It is not personal, it is jsut a waste of time to try and have to extract info out of you just to try and help you.

hugs and kisses,

Geeto67, asshole +1

quote: You're a very mean man. Don't read fuzzybutt's "new bike" thread.
would that be the thread where I told him the bike was better served as a desk?


PS: Izzy, you're actually local to some of us so if you want to talk about this in person and want some genuine help there are plenty who open our ears and garages to ya. Also think about joining the NYCvinmoto list. I'm really a nice, generous person in real life...honest. Rosko can vouch for me. Hope we haven't chased you away.

Edited by - Geeto67 on Feb 08 2007 2:31:27 PM
 

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$1500 dollor jacket ....holly
can it clean the house or do laundry. here i am making fun of $1500 dollor jacket when my tool box cost $5,500 im stoopid

cafe racers!!!!!
bobbers!!!!!!
 

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quote: quote: You're a very mean man. Don't read fuzzybutt's "new bike" thread.

would that be the thread where I told him the bike was better served as a desk?

Yes, that would be the one, and I said it because I asked a similar question. I don't think Joe's a very mean man. I was kidding. I guess I should have made it a little clearer, but I thought the reference would be picked up. Joe's answer made me laugh, especially the Geoff Duke part.

I'm really only here for the hate anyway.
 

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Hey Izzy, If you just want clip on's, measure your forks and order some off e-bay.

Push your forks up enough through the top tree and attach em there...
Probably enough for now... I've been on this forum enough to know that if these guys say you don't need better forks (specifically the dudes who wrote back to you with those kind words).. then you dont need em.

Shag it, go cheap and pick up some clubmans, I'd say you'll be satisfied.

Hey By'
 

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Discussion Starter #11
No offense taken. Check out www.skyhighforafrica.com. Its a site I put together via satellite modem while on a 10,000 mile bike trip through Africa, so yes I know where the clutch is and how to get the lunker off the kick stand.

Second, I've been restoring vintage BMW's (R50s, R26 etc) for the last 8 years, so yes, I have a hammer, and know that a set of points is not where you plug your wife's vibrator to charge before satisfying her with it. (No offense to viagra brigade).

Now stop being a bunch of snooty assed Yale graduates, acting like your bikes run on Champagne and expel Eau de Cologne, while you sit on the saddle like the “Princess and the Pea”, gathering insects in your up-tilted nostrils as they jet off your stiff upper lips.

That out the way, I asked the question because I have dealt mostly with the old fashioned forks on the beemers and have no experience with the more modern flair of clip ons etc. I was wandering just how much is standard on the front end of these bikes and what one does for example when the neck length is not the same as your replacement forks but the bearing dimensions match up. What does one do if the new forks you have put on have space for 2 brake calipers but your wheel has only one rotor…is it safe to run the forks with just one caliper etc. I’m not asking for step by step, I’m more asking for stories and experiences, that’s all, so lighten up.
 

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quote:


No offense taken. Check out www.skyhighforafrica.com. Its a site I put together via satellite modem while on a 10,000 mile bike trip through Africa, so yes I know where the clutch is and how to get the lunker off the kick stand.

Second, I've been restoring vintage BMW's (R50s, R26 etc) for the last 8 years, so yes, I have a hammer, and know that a set of points is not where you plug your wife's vibrator to charge before satisfying her with it. (No offense to viagra brigade).

Now stop being a bunch of snooty assed Yale graduates, acting like your bikes run on Champagne and expel Eau de Cologne, while you sit on the saddle like the “Princess and the Pea”, gathering insects in your up-tilted nostrils as they jet off your stiff upper lips.
I like this guy....welcome to the fold

quote:
That out the way, I asked the question because I have dealt mostly with the old fashioned forks on the beemers and have no experience with the more modern flair of clip ons etc.
If you've worked on old beemers then these jap bikes should be a piece of cake. Comapred to an earls fork a telescoping fork was designed with crayons.

quote:
I was wandering just how much is standard on the front end of these bikes and what one does for example when the neck length is not the same as your replacement forks but the bearing dimensions match up. What does one do if the new forks you have put on have space for 2 brake calipers but your wheel has only one rotor…is it safe to run the forks with just one caliper etc. I’m not asking for step by step, I’m more asking for stories and experiences, that’s all, so lighten up.
A lot more than you would expect is standard on these bikes.

I am not sure what you are referring to when you say neck length, are you talking about the stem length? If the bearing sizes are the same in most instances you can just make a spacer and bolt the top clamp on.

As for the caliper lugs on both forks welcome to honda. They did it for a ton of bikes and most can be converted over to dual disc. On most bikes the fork lowers are the same, on some they planned a dual disc and never installed it (in rare occasions they offered a kit from the factory to bolt on). Most 70's hondas are single disc fronts (your cb350 four definatly should be) so yes as long as you have all the parts there then she is good to rock down the highway.

I had a friend who built a cb350F to look like an early ducati (called it the honducati). He had megaphones, a honda dream seat, and lights and signals off of old brit and italian bikes. With clip-ons and makeshift rearsets it really looked the part. The bike was wrecked however when a car made a right in front of him. It was a slow but fun bike.

if you can find a 400f motor and swap it in your frame. The 350F may be the conservative transportation of the honda set, but the 400F is it's big brother doing 8-balls in the back of a monte carlo.

BTW, we fuck around a lot here so if someone is giving you the business give it right back, so long as it is funny.
 

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Discussion Starter #13
Thanks Geeto!

I was actually given the bike...so no excused (or complaints) there either. Is it possible to rebore the 350F to a 400. Is there a lot more that would have to change to match the power of the CB400?

BMW R50
 

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quote:
Thanks Geeto!

I was actually given the bike...so no excused (or complaints) there either. Is it possible to rebore the 350F to a 400. Is there a lot more that would have to change to match the power of the CB400?

BMW R50
You know I am not sure, I've never had them apart side by side. The guys at www.sohc4.us might know better. I've been told they are the same bottom end but how much the same I am not sure. Honda has a few engines that share mounts but no internal parts (like the cb500/550 and the cb650). I have ridden both and I can tell you the 350 feels like transportation and the 400F feels like a barn burner at the top of the revs. The 400F header is dead sexy to boot.
 

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jeremy raced a 350/4 against me several times. it wasnt death slow, like we had some great races, so he would know more about the mods. the stem length is the only real fucked up thing you might have to deal with. i prefer the grind and press method. that way you have the same bearing. it is possible to just drop a few washers on sometimes to make the difference up though. on the bottom. like was said, most forks have lugs on both legs for dual disk conversions. to swap your wheel to another set of forks may be tricky. if its the same as the 350 twin it has the 4 bolt rotor, which is smaller than most. the later bikes, 550 etc...had a larger rotor with 5 bolts. so youd need to make a caliper mount. if you stick with the smaller rotor. at least thats my guess. or switch out to a different wheel. that way you just yank the entire front end. at least thats my opinion. most of those honda single puck disks pretty much sucked. and in the rain the are really non existant. like useless.

go for the 550 front end. 35mm. cheap. and it'll add some stiffness and you can find them easily in good shape.


now if you'll excuse me, i need to go refill my tank with a bottle of dom. my bike likes the cheap stuff.

jc



Edited by - joe c on Feb 08 2007 9:31:07 PM
 

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Discussion Starter #16
While I'm stacking up the stoopid questions, I though I'd throw one more in here. What pipes are compattable with the CB350 Four. I'm looking for a 4 into 1. With the CB400,450,and 550 all work?

Thanks

BMW R50
 

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Izzy,
I believe a 400f cylinder will fit on the 350. I am not sure the 350f cylider walls are thick enough to bore to 400. The 350 has a 5speed trans and the 400f a 6 speed. The 350 and 400 should use the same exhaust. The 500/550 are different. The front forks on the 350 and 400 are not set up for dual calipers. It is also difficult to mount a second disk to the stock hub. You would need to do some machining to make it work. If you want dual disks then I would go with a different front end. Personally I think the 350F has one of the best gas tanks for the cafe look of that vintage Honda.Finally, if you remove all the covers and crap off the 350F front forks, they are the same as the 350 twin and 400F front forks. They are definatly usable on the street and many of us have raced on them.
Good luck and ignore the stupid stuff most of these fucktards(I love that word) have to say since most of the smart stuff is really good.

Ken

AHRMA 412
Vintage racing - old guys on old bikes
 

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Oh Yeah, the 350f and 400f are only kinda doggy. At lower revs, they just don't make any power, but if you keep the RPM up between 7500 and 10000 they are ok. The problem is that if you ride them on the street that way it gets really tiresome and loud. They are actually better on the racetrack than on the street. The 400f has more bottom end from the extra 50cc so is a better street ride. More power, such as from pipe, porting and 550 or 750 carbs, (those things all work), won't make it any better on the street unless you enjoy a loud peaky screamer( insert sexist remark here). If it were mine, and I am thinking about one, I would go with an older cafe look with 4 into 4 black megaphone exhaust, stock tank classic glass seat drum front brake and clip-ons. It would look cool.

Ken

AHRMA 412
Vintage racing - old guys on old bikes
 

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As for your initial question, the easiest forks to mount are 35mm Honda forks from the late 70s/early 80s because a lot of the critical dimensions are the same. You will most likely have to swap stems or use a spacer - the stem swap is better because other weird shit happens with a spacer (ask me I know because that's what I was planning to do first).

CB450/500t stems are probably the same length as yours but might not be. Later model forks including various CBR/GSXR, etc. are cool but the length, offset, front wheel design and various other things make them a much harder swap. Plus they don't look vintage, if that's the look you're going for.

The funky swinging brake link disc brakes on 70s Hondas suck. I don't care what anyone else says, it's a Mickey-mouse setup that was designed to avoid having a floating caliper mount directly to the fork. I've never been able to figure out why they didn't just design a floating caliper but whatever.

To avoid said sucky brakes, you want the forks (or at least the fork tubes and legs) from a later CB750F, CB650 or likewise. They will be too long but you can either slide them up or have them shortened. Or use a spacer under the top out spring like I did (which is not the best way to do it because you lose travel but it's cheap). CB450 and 500/550/650 forks are close to the same length as CB400f, but they have the aforementioned sucky brakes. Use the longer forks but just watch the travel so they don't bottom on the triple clamp.

Anyway, the other problem is offset. If your bike uses the same or similar forks to a CB400f, it has the same offset as CB450/CB500T, CB650 Custom and early CB750k models so you want those triple clamps to maintain stock offset. CB750f, CB500/550, CB650 Custom and CBX have different (less) fork offset that will give you more trail and heavier steering. CB450/500t have rubber-mounted handlebars which is cool or you can ditch the mounting and have a cleaner top clamp with clip-ons. CB750k lower triples are almost the same as CB450/500t but the stem is longer and the top triple has solid bar mounts. CBX triples have less offset and are aluminum with no upper bar mounts which is even cooler, but they have a weird fork stop which means using them is hard.

Still with me?

For some reason Honda uses a million different gauge mounting patterns and brackets, so the chances of finding one that lets you use your stock gauges with the new fork are minimal to none. You will most likely have to fabricate it.

All of these forks are simple damping rod forks which means they're either harsh in compression or dive-happy, or both. You can modify the damping rods if you're handy but you won't be able to get the compression damping perfect because of the design.

The only exception to this is late CB450 forks which have a real damper inside them like Norton Roadholder forks. Good luck finding a set that is decent, and of course you have the Mickey-mouse brakes to deal with.

Oh, and one more thing about dual discs - The Mickey-mouse brakes can be made into duals with the correct fork lower legs and an extra caliper and rotor, but the speedo drive has to be modified, or so I'm told. The rotor bolts to the hub with six through-bolts so you just mount another on the other side.

The good calipers (and their matching fork mounts) unfortunately only work with newer, thinner, lighter 5-bolt rotors which, also unfortunately, only come on ugly Comstar rims or, on some CB750ks and CB650s, as a single disc spoked wheel.

I have never seen a dual-disc, spoked wheel that works with the 5mm thick late model rotors and matching calipers. Oh, and most of them are 19" so you will have to search before finding an 18" wheel to match your stocker. This applies to the above too.

The best calipers for the above swap are the ones on 1980 CB750fs because they are dual-piston and will still clear spokes.

Now if you've read this far there's another swap I considered but ultimately rejected: GL1000 goldwing. It's got 37mm sliders and solid-mounted calipers, a 19" spoke wheel with an alloy rim and dual discs. The problem for CB400f/CB450/CB550 etc. bikes is the extreme length of these forks - about 2" longer than CB750 or almost 4" longer than stock. Yuck. Also, the top triple has cast-in risers almost 4" tall that cannot be cut off without seriously weakening the top triple.

There are guys on here with a hell of a lot more experience than me, and I'm sure they will add to (or contradict) what I've listed.

This information is what I've collected over the past 6 months by hanging out at the bike junkyard and scouring Honda parts catalogs.


Good luck!
 

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when geeto says a bike is slow you have to take into concideration he is not a "Little" guy.So if your a jockey sized rider slow is a different prospective.Power to weight as you know is everything...

Im so far behind ,that I think Im in first.
 
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