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Discussion Starter · #1 ·
On my 74' CB 450 K7 I just recently acquired, I like to upgrade the suspension a little for a more spirited ride but not too overly harsh.

Thinking about fork spring and rear shock upgrades, as well as steering head bearings and swing arm bushings ?

Are there upgrades out there that you guys have used and would recommend ?
 

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I replaced my steering bearing on my CB360 from the original ball and race setup to a hybrid All Balls tapered bearing lower + ball and race upper. The steering feels a lot more "secure" now, not sloppy like before. NOTE: This is on my current "project" which is not ready to ride/start up so I have not yet taken it on the road.

For the rear suspension, I replaced my rusty/spongy shocks with a set from Hagon. I thought it was really cool that they tailor a set to you based on your riding style and your weight.
 

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Bronze swingarm bushings are almost a must-have upgrade. Steering bearings may help, though the stock ball bearings work ok - biggest problem with later 450's is the absence of the early friction steering damper, which is a very cool device. I liked it so much I incorporated one in my K4 resto/mod.

Forks - depends on how much money you have. Stockers are pretty miserable for sure.
Different springs may help some - for the best, replace them with Ceriani forks, best in the known universe. Very expensive now - when I bought two sets in the early 70's, they were $250 each (with stems and clamps), now they're $1200-1500 (maybe more, forks only), and worth every penney. It still boggles my mind just how good these forks were, never felt anything like them. Whenever I remember that I sold both sets for $100 each I get sick to my stomach.

Shocks - stock Honda shocks are about as good as a pair of twisted rubber bands. Almost anything would be an upgrade. Hagons are pretty good, and IKON (exact copies of old Koni's) are very good. Both are a bit pricey, but make a radical improvement to handling.
 

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Italians sure knew how to make bikes that handle well. Ceriani forks were great when they were new. Marzocchi and Paioli as well (but they had various tiers, from top racing stuff to mass produced suspension).

However, a very good solution would be to use Moto Guzzi forks. The V65 had 35mm tobes, same as the CB450 (I think the V35 and V50 had 32mm). The Nevada and a few other models probably also used 35mm ones. These forks are special, because Moto Guzzi was the first manufacturer to use real cartridge forks. This allows manufacturers to make modern cartridges that fit into them. The stock ones were nothing too great, but you can easily find a new modern set of adjustable bitubo cartridges that will make the forks function a lot like brand new forks, and they fit right in. But they also have the 70's styling, and if polished, they look really nice. Also, the double piston Brembo calipers would fit on those forks, and those are a lot better than any 70's japanese calipers. You would probably need to use the Moto Guzzi front wheel and their cast iron discs (which, again, are a lot better than any 70's stainless disc). So, with this setup, you'd get a front end that is performance-wise comparable to modern forks, yet with the classic styling. Here's my 77' V35, that had such cartridge forks (just 32mm):



Replacing the stock triple trees for aluminium ones would not be a bad idea either. Stronger triple trees sometimes make a big difference. You can also get spoked front wheels (f.e. from a Nevada model, or similar). If you replace the triple trees, perhaps it would be even easier to find 38mm forks from the big-block models (f.e. T5), those will be even more rigid, and there are probably even more aftermarket cartridges for them.


For the shocks, Marzocchi did make performance aftermarket shocks specifically for Honda (Italian bikes otherwise all had eye to eye shocks):


These are quite good, and easily rebuildable. You can adjust the oil pressure by pressurizing a rubber bladder. I have a few pairs of the older (f.e. AG1) adjustable marzocchi shocks, but I do not know if they made such for Honda. These were made in the 70's, and look more period correct (but they usually come with a special price):



I've a pair with chromed springs and polished aluminium. Those fit perfectly on classic bikes... I think some sporty Ducati bevel twins used them originally.




80's Benelli models were esentially such bikes. They've completely copied the Honda engine, but used their own frame and suspension. De Tomaso owned both Moto Guzzi (a huge factory at the time, and a big pride for Italians) and Benelli (a small factory that made two strokes). They made these Honda clones in the Guzzi factory, mainly with Benelli badges. They had the Guzzi suspension. They handled a lot better than a Honda, but they were more expensive and never really sold well.

 

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Discussion Starter · #6 ·
I've installed All Balls steering stem bearings before on other bikes. A little bit of a chore and don't always fit flush. Bronze bushings I've installed as well but didn't have an inner metal sleeve to drive out, they where plastic so much easier.

How difficult is it to installed front bearings and rear bushings in these bikes ? I couldn't tell from the pictures if the inside bore of the bronze bushings had any grooves to help store grease ?

I'm looking into Hagon shocks but not sure on the front springs yet ?
 

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I've installed All Balls steering stem bearings before on other bikes. A little bit of a chore and don't always fit flush. Bronze bushings I've installed as well but didn't have an inner metal sleeve to drive out, they where plastic so much easier.

How difficult is it to installed front bearings and rear bushings in these bikes ? I couldn't tell from the pictures if the inside bore of the bronze bushings had any grooves to help store grease ?

I'm looking into Hagon shocks but not sure on the front springs yet ?
Bronze bushings don't require much greasing, if ever.
450 swingarm bushings can be a giant PIB to remove, especially the older metal ones.

The steering bearings/races are the same parts on dozens of models, and readily available from Honda for cheap.
They're pretty easy to get in and out, long as you don't get it crooked. Just need a big ol' hammer and a long punche or drift.
 

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Discussion Starter · #8 · (Edited)
bushrrforkpivot_medium52108457300-01_c7ba.jpg I don't know if my swing arm bushing are "steel" or "plastic" ? But my question is if they are steel, wouldn't the wear factor be minimal as opposed to plastic ?

Also, Race Tech sell fork springs for my bike and have various linear ratings depending on bike and rider's weight. Anyone used their fork springs before ?
 

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I have to add my 2¢ which is different from the other posts. I think the stock CB450 suspension is fine for what it is. The K5 through the K7 had the same front shocks that Honda put on the CB500F. Earlier disk brake 450s had the same shock as the CB750. Later Honda rolled this shock design to the 750.

This was an advanced shock design that Honda ran through the 70s. Even the Goldwings had a similar design. About 1980 Honda added Teflon bushings. this significantly reduced the amount of 'stiction' in the fork. You can spend a lot of money on exotic replacements and make an improvement. The down side is you may lose the classic gator front end of your bike. On the rear end stock swing arm bushings are metal and there is a felt weather seal that is held in with plastic end bushings. There really isn't anything wrong with this setup. Like the front fork, is it is in good condition and has fresh lube (or oil) it will perform just fine. Like Bill says, stock shocks were not very good when they were new. It was common for people to get Ikons back in the day. However, shock technology has moved a lot since the early 70s. I have Hagons on my 450 and they are fantastic. Tapered stem bearings are a good upgrade. When you are looking at shocks fitting them can have interference problems if the diameter at the bottom is too large (hit the chain guard) too long (hit the mufflers).

I have recommissioned my front end with new fork tubes (Forking by Frank) and the All Balls tapered stem bearings. The swing arm was rebuilt using new stock bushings and felts. The rear shocks are standard Hagon narrow SS springs on black cartridges. The bike rides great, it is every bit as good as both my CB750s ('74 and '77F) were back in the day. The most I have done on it is 260 miles in a day. A 1974 bike will never be equivalent to a new bike. The performance will only be brought up so far. I've been out with the Vintage Motorcycle Enthusiasts (VME) in Seattle. They host a Pre-1975 run. 76Twin and I were the only Honda Twins on the ride. Mostly they were British twins and a couple of old Harleys (there was a '55 Harley KE that made me want). Our Hondas were vastly superior to the other bikes.

Jim's CB450.jpg

If you want a better bike, get another. This is my mile muncher. I paid $500 for it. It had been off the road for 11 years. Moral of the story, get the 450 done and move on to the next. Use the bikes for what they are.

Jim's GL1200.jpg
 

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I don't know if my swing arm bushing are "steel" or "plastic" ? But my question is if they are steel, wouldn't the wear factor be minimal as opposed to plastic ?
They're not very good steel, if they're steel at all - good for 10,000 miles or so.
Somewhere on this site is an old post of mine (with photos) showing the de-evolution of those swingarm bushings from crummy metal to even more crummy plastic.
The later 450's had really crummy bushings, non-metallic.

You'll find out what yours are made of when you try to get them out.........,
 

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They're not very good steel, if they're steel at all - good for 10,000 miles or so.
Somewhere on this site is an old post of mine (with photos) showing the de-evolution of those swingarm bushings from crummy metal to even more crummy plastic.
The later 450's had really crummy bushings, non-metallic.

You'll find out what yours are made of when you try to get them out.........,
Most people never grease the swing arm.
 

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Bill, Do you have any "Advice" how to remove these bushings ?
If they are the later (plastic or some weird material), just use a long drift or punch to whack them from the opposite side - they'll usually shatter into pieces (nice, huh?).
If they're the older metallic ones, you have a real job ahead of you - it can turn into the most frustrating job imaginable. There are times I've just given up and taken the swingarm to a machinist, let them deal with it.
I've attached a PDF of my original post here, years ago. View attachment swingarm.pdf

Jim's comment about most people never greasing the swingarm at all is accurate - of course that accelerates the wear on the old style bushings. Bronze bushings get just a little grease for assembly, then never need grease again.

I also have to voice an opnion opposite to Jim's (sorry Jim) regarding the quality of Honda forks of the era (ALL of 'em) - they suck, in a word. And I always hated those rubber fork gaitors, I think they look awful, and promote rust on the tubes they cover.
Just a 5-minute ride on a bike with Ceriani forks will ruin you for life - that's how much better they are, they make Honda forks seem like a clunky bad joke.
 

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Discussion Starter · #14 ·
I can testify that the fork gaiters "do" promote rust on the the fork tubes they cover inside, I have a 74' CB 750 K4 and yes the fork tubes are rusty.

I have a complete front end off my 79' Honda CBX I restored several years ago, I'm wondering ?
 

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My garage kept CB450K6 has no rust under the gaiters.
 

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If they're 35 mm tubes, the whole front end could just slide in to the clamps. You may have to adjust the tube lengths a bit, not sure (slide them up in the clamps).
That assumes that the new front end has the same spacing between the forks, etc. If not you may have to experiment with stems and clamps.
On my 450, I used CB400T2 front end (32 mm forks), with CB360 clamps (also 32 mm, same fork "width" and offset) that had a 450 stem welded in.
 

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Discussion Starter · #17 ·
They are 35mm fork tubes ( 79-80' , later ones 81-82' had 39 which I upgraded to ). Have to do some measurements and see if it's worth while ? Would be gaining dual disc brakes but also weight too, so may not be that good either ?

Something that did work for me on my 74' CB 750 K4, I had the brake disc drilled, upgraded to semi-metallic brake pads, steel braided brake lines, and smaller piston M/C ( 14mm to 12.7mm ). A noticeable difference in braking performance. Might be something to consider on the 450 ?
 
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