Topic: Honda CB750 buying used shocks - good idea or bad idea??

[kyle750]

KONI for Honda sales brochure showing the 76 series shocks.  Photos courtesy the KONI 76 Series Motorcycle Shocks facebook group

Purple and Gold Cafe Racer with clear plexi sport fairing -  Just Amazing 

[PeWe]

My Ikon shocks are 339mm  (center eye <-> center eye)
Sold for CB750 K0-K6.

My old Marzocchi AG Strada 335mm according to  Marzocchi parts manual.

Divide with 25.4 to get inch

The spring setting change the ride height.

[kyle750]

I just received an evaluation from a KONI expert.  Thank You Sir!

They look fairly good why rebuild them ? 5 level height adjuster at base and 4 or 5 rebound adjuster under the rubber cover at the top. Normal setting 2-3 base unless you are big, rebounds start with 2 and see how they go.

And a very nice message from the seller of the shocks.  Thank You Sir!

I don’t have much history, unfortunately- these were just with some parts. Happy to hear they made it to a good home

[kyle750]

KONI finned aluminum shocks    very cool shocks    although I don't know if they were ever made for the Honda CB's

I understand the fins on the air cooled HONDA CB engines are designed for cooling but fins on a shock?  I did not know that shocks can overheat and need extra cooling.

Photos courtesy the KONI 76 Series Motorcycle Shocks facebook group

[rotortiller]

That was a fin fad. Some manufacturers added a finned reservoir to the shock suggesting improved performance and better tech. Manufacturers often looked for ways to con the consumer be it bling or some other useless tricked out tech BS. Reminds me at times of a politician or car salesman. Anti-dive,  use your head. Some people shop for economy, durability, function and fit but in a personal ratio with appearance less important. There are others who build for fast appearance, cool looks; accept an uncomfortable ride with appreciation for that aspect but employ short rides. Then there is that poor bastard that falls into all categories and cannot stop buying bikes and parts, a creature often found stealing from the grocery fund!

[kyle750]

Then there is that poor bastard that falls into all categories and cannot stop buying bikes and parts

Yep . . .  that sounds like the current path I am taking  So finned shocks is just a useless marketing gimmick but serves no real function? 

[BenelliSEI]

By design, shock absorbers generally squeeze oil through a restricted opening. This action, and the piston rising and falling will generate some heat…… on the car I’m road racing this past few years shock reservoirs contain chambers of pressurized nitrogen and oil. The reservoirs are mounted remotely, inside the car to keep them cool. Leaving them close to overheated brakes, discs and tires doesn’t make sense.

On our under stressed road machines, remote or finned components are strictly for the “looking cool factor”! 

[kyle750]

Here you go!

[rotortiller]

So finned shocks is just a useless marketing gimmick but serves no real function?

True. The oil in the shock does not get hot enough to need cooling when riding the bike. Look at the suspension travel on a motocross bike with one shock, way more fluid is moving and the shock is subject to severe conditions compared to a street bike. They need no cooling fins and the shock is buried under plastic with limited air flow over the surface.

[seanbarney41]

So finned shocks is just a useless marketing gimmick but serves no real function?

True. The oil in the shock does not get hot enough to need cooling when riding the bike. Look at the suspension travel on a motocross bike with one shock, way more fluid is moving and the shock is subject to severe conditions compared to a street bike. They need no cooling fins and the shock is buried under plastic with limited air flow over the surface.

I can't agree with that.  It just depends on how demanding one is about suspension.  I agree that 90% of street riders are not gonna have a problem with over-heated shocks.  Modern shocks design their valving to not heat the oil in the first place.  But if you are meticulous, it's easy to notice variations  in a lesser shock's performance as the ride gets longer, bumpier, or you start pushing harder.  If you don't intend to ride long, on poor pavement, and "always" obey traffic laws, there really is not much point in using anything but some perfectly chromed and correct stockers.  Also, no reason one can't just ignore a poorly designed shock's overheated performance and enjoy the ride but that doesn't mean that efforts to improve the performance of your vintage motorcycle with period correct parts was or is a marketing gimmick.

[kyle750]

Older model 76P-1296 aluminum body KONI shocks on a Honda CB750 from an owner in Denmark.  The owner has been looking for someone to rebuild his shocks but the parts for the older model 76P are no longer available.   The shocks I just bought are the later 7610P-1296 and parts are available to rebuild. Just lucky that I bought the later ones.

[kyle750]

I just received a very reassuring message from a KONI expert who has rebuilt over 20 sets of 7610 shocks. Thank You Sir!

Your shocks look to be in great shape and should be good to go. These later "top dial" don't have the problem of the earlier KONIs that get plugged up from a melted plastic top out washer inside. So unless they need seals they should be working fine.

He has also generously offered to guide me through replacing seals if needed.  After receiving lots of positive feedback  I am going to go ahead and ship the KONI shocks to me here in Thailand. 

[PeWe]

Those shocks look good too!

You are soon the Koni/Ikon expert
This thread has good info about the old Koni shocks that can be seen on new Ikon shocks.

[kyle750]

After a little checking on the IKON parts database I found that the Honda CB750 KONI 7610-1296 shocks use the KONI/IKON 235 springs with a tri rate of 235-18/25/33.  The springs on the incoming shocks look usable but have some rust.  I could repaint the old springs but I saw these for sale on Ebay for only $50 with free US Delivery (normal price $100 from IKON).  Hard to beat this price and they are new.  As they have never been used the compression should work like new and perfect black paint.  Why bother with the old springs when I can just buy new and install??

https://www.ebay.com/itm/133778428577

[kyle750]

Over at the KONI shock group experts have told me there is no need to replace the springs

The Springs are not a problem.The compression springs don't wear out or become soft.

Simply have the original springs re-powder coated