CB350F vs. CB400F

buckeyebike

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Does the CB350F and CB400F share the same frame? What's the difference between the two, other than the obvious?
 
Yeah the obvious, 409cc vs 347cc or something like that. The 400 has a more aggressive, racer-like riding stance and the 350 is more upright, thighs parallel to the road. Someone correct me if I'm wrong, but I believe the 1975 400 had drag bars and 76-77 had higher bars similar to that of the 350.

I own a 350 and honestly, I feel like that extra 60cc would make a world of difference. If you get a 350, you'll find yourself less than overwhelmed with the performance.
 
Not exactly the same frame, but very similar.

Tristan is correct, Honda changed the 400f bars (and the pegs) on the '77, and also moved the passenger footpegs from the swingarm to an additional bracket on the frame.

The 350f ran 4 into 2 exhaust systems, so had different frame brackets to the 400f, which ran a 4 into 1.

Engine mounts are the same.
 
Actually a 4 into 4 and a 4 into 1 were available for the 350 as well....plus the seat for the 400 looks more proportionate to the frame, where as the 350's seat looks like it belongs on the 550.
 
I think the 400 has a 6 speed tranny and the 350 does not (5 speed?). The frames will have different brackets to accomodate the obvious stuff (exhaust, etc).
 
Youre right eyhonda, 350 has 5 speed and 400 has a 6 speed. Also, the clutch accuator is fully exposed on the 350, but has been protected behind a cover from what I can see on the 400. Makes for a sleeker looking bike, I think.
 
Tristan said:
Youre right eyhonda, 350 has 5 speed and 400 has a 6 speed. Also, the clutch accuator is fully exposed on the 350, but has been protected behind a cover from what I can see on the 400. Makes for a sleeker looking bike, I think.
I kinda felt like that stuff fell under 'the obvious'. The bikes are so very simular, the frame, forks, shocks, brakes, and wheels, are interchangeable. Aside from some aesthetic differences and of course the engine the bikes are very much the same.
 
veloracermike said:
I kinda felt like that stuff fell under 'the obvious'. The bikes are so very simular, the frame, forks, shocks, brakes, and wheels, are interchangeable. Aside from some aesthetic differences and of course the engine the bikes are very much the same.

What may seem obvious to you, might be totally elusive to another...thus the reason the original poster asked what the difference between the two bikes was.
 
It might be easier to answer the question if the OP stated his intention or plans. If you're planning to fit a 400f motor in a 350 frame, then the frame would have to be modded with an exhaust bracket and a number of other things to consider (tank, seat, swingarm, etc). Are you asking the differences between the bikes or the motors?
 
Tristan said:
What may seem obvious to you, might be totally elusive to another...thus the reason the original poster asked what the difference between the two bikes was.

Not to be argumentative but the OP put into his post "besides the obvious" This gives the impression that he understands the things the two bikes share.
 
I'm finishing up a build with a CB400F engine in a CB350F frame. Yes, they're compatible. I like the CB400F front pegs much better; they're set back about 6 inches. Hate to give this away, but they will also work on 550s and I'm guessing 750s, with some minor mods, for a "semi-rear set" kind of deal. I guess since I'm sitting on 3 sets I'm good for now. The rear pegs, however, I like much better on a CB350F as they are mounted to the frame. On the 400F, they are mounted to the swing arm. WTF. If you switch over to 400F pegs you'll need the shift linkage (obviously) but also the rear brake lever. On the left side, the new shifter with linkage will interfere with the side stand, but not if you cut off the little ring of metal that comes on them; the main part of the stand is fine. On the CB350F, the mount for the brake lever (a small tube welded on to the frame) sticks out about 1 or 1.5 inches more than on the 400F, so if you mount a 400F brake lever on a 350F frame, it will stick out a bit from the engine. I used a grinder with a cutting wheel to cut this off, and stuck some of what I cut off on the brake lever behind the mounting tab (essentially making it more like the CB400F). Takes a little finangling for the brake light switch, if I remember correctly, but nothing major. Tanks fit just fine. Side covers are, obviously, different, but I am not running side covers. Seats are different. Handlebars on a 400F had a rise of about 2 inches, and on a CB350F the rise was about 4-5 inches. As far as I know, there was no stock 4-1 exhaust for the CB350F; the CB400F is recognized as the first stock 4-1 exhaust system (someone correct me if I am wrong here). That being said, a stock CB400F 4-1 exhaust bolts right up to the CB350F engine, although you can't use stock CB350F pegs and need an exhaust mount in the rear. Key is mounted differently (as are idiot lights). The CB400F has a really ugly headlight and front turn signal mount, and the CB350F has cool looking headlight ears and gaiters for the front forks. Forks are same diameter (33mm) and are interchangeable. CB400F has 6 gears. I've found with both that keeping stock exhaust and switching to pods doesn't require rejetting, just tuning, with both bikes. I will let you know what happens with my new bike when it's up and running -- I am running custom 4-4 exhaust and pods. Different front fenders on the CB400F and CB350F, too. Oh yeah, you can turn the headlight off on the CB350F, but not on the CB400F; it's always on when the bike is running. Different horn, too; CB350 is cooler and covered in chrome. I guess that's all I can think of now...

I know a ton of people slag off the CB350F when compared to the CB400F, but I honestly like the CB350F styling better (cooler tank with knee cuts, cooler seat, rear pegs). And I gotta say, I've had a CB350F for about 15 years. Rebuilt the engine back then, and with the occasional carb overhaul and annual tune-ups (and a slightly rattling cam chain...) the thing runs super smooth. I hold 75 easily on the freeway, which isn't too bad, but it'll go faster (I've done the ton on one of my old CB400F bikes, however).

Recent photo here: http://wordsofwezdom.blogspot.com/2012/08/cb350f400f-update.html
 
carnivorous chicken said:
I'm finishing up a build with a CB400F engine in a CB350F frame. Yes, they're compatible. I like the CB400F front pegs much better; they're set back about 6 inches. Hate to give this away, but they will also work on 550s and I'm guessing 750s, with some minor mods, for a "semi-rear set" kind of deal. I guess since I'm sitting on 3 sets I'm good for now. The rear pegs, however, I like much better on a CB350F as they are mounted to the frame. On the 400F, they are mounted to the swing arm. WTF. If you switch over to 400F pegs you'll need the shift linkage (obviously) but also the rear brake lever. On the left side, the new shifter with linkage will interfere with the side stand, but not if you cut off the little ring of metal that comes on them; the main part of the stand is fine. On the CB350F, the mount for the brake lever (a small tube welded on to the frame) sticks out about 1 or 1.5 inches more than on the 400F, so if you mount a 400F brake lever on a 350F frame, it will stick out a bit from the engine. I used a grinder with a cutting wheel to cut this off, and stuck some of what I cut off on the brake lever behind the mounting tab (essentially making it more like the CB400F). Takes a little finangling for the brake light switch, if I remember correctly, but nothing major. Tanks fit just fine. Side covers are, obviously, different, but I am not running side covers. Seats are different. Handlebars on a 400F had a rise of about 2 inches, and on a CB350F the rise was about 4-5 inches. As far as I know, there was no stock 4-1 exhaust for the CB350F; the CB400F is recognized as the first sock 4-1 exhaust system (someone correct me if I am wrong here). That being said, a stock CB400F 4-1 exhaust bolts right up to the CB350F engine, although you can't use stock CB350F pegs and need an exhaust mount in the rear. Key is mounted differently (as are idiot lights). The CB400F has a really ugly headlight and front turn signal mount, and the CB350F has cool looking headlight ears and gaiters for the front forks. Forks are same diameter (33mm) and are interchangeable. CB400F has 6 gears. I've found with both that keeping stock exhaust and switching to pods doesn't require rejetting, just tuning, with both bikes. I will let you know what happens with my new bike when it's up and running -- I am running custom 4-4 exhaust and pods. Different front fenders on the CB400F and CB350F, too. Oh yeah, you can turn the headlight off on the CB350F, but not on the CB400F; it's always on when the bike is running. Different horn, too; CB350 is cooler and covered in chrome. I guess that's all I can think of now...

I know a ton of people slag off the CB350F when compared to the CB400F, but I honestly like the CB350F styling better (cooler tank with knee cuts, cooler seat, rear pegs). And I gotta say, I've had a CB350F for about 15 years. Rebuilt the engine back then, and with the occasional carb overhaul and annual tune-ups (and a slightly rattling cam chain...) the thing runs super smooth. I hold 75 easily on the freeway, which isn't too bad, but it'll go faster (I've done the ton on one of my old CB400F bikes, however).

Recent photo here: http://wordsofwezdom.blogspot.com/2012/08/cb350f400f-update.html

And there ya have it folks!!!
 
Thanks for the details fellas. . . I have been looking for a 350F for the race set below, but there is a fellow locally who has been trying to sell a '75 400F for quite some time. But, I am only interested if the set fits.

350FCafeSet008.jpg


350FCafeSet010.jpg
 
Buckeye, almost certainly will fit, although since the seats were slightly different the seat mounts were too, if I remember correctly (I shaved mine off...). But if you're not using the mounts, then should be sweet as a nut. Doesn't look like it will use the mounts. Very nice set!

Thanks Kwality! I've been spending too much time tuning OPBs and not enough on mine. I need a solid 5-6 hours to wire that thing up correctly and fire it up. This weekend? or next... and after that, more stuff to go, CB175, CB750...
 
Hey I've bought a 400F, and in the frame I noticed that the Frame number starts with cb350F, so I dont know if the frame was changed or the first edition was built in the 350 Frame
 
I've never heard of early CB400Fs going into 350F frames from the factory, but I could be wrong. Likely someone put the 400F engine into a 350F frame at some point. Does your bike have 400F pegs (that sit behind the mounts)? Does your kicker clear the pegs?
 
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