Rear Shock Absorber Upgrade - Best to Worst

This thread got me to do some shopping and I see I can get a pair of Gazi SL400300 for $400CAD including shipping, thats about $37.95USD I know someone else asked earlier upthread but does anyone know how good/bad these shocks are?

missionkz wrote: So... getting back to one of my questions.... what is an estimate in cost to have an old set of my Boge-Mulholland shocks rebuilt?

Try asking at Marks Swap Meet, lots of info on those shocks there.

I give that guy credit for trying to improve on those Ebay shocks. However, even if you can get one of those shocks to work, how long is it going to last? Did they hard anodize the shock body or use good chrome on the shafts? If not that piston band is going to wear out the inside of the shock body.
The site is a little confusing to navigate but I found some info on those reservoir shocks:

"Further analysis revealed that this damper, unlike the Model 1, is not a proper reservoir type shock. All of the parts are there to accommodate a functioning reservoir, though the manufacturer never machined the port that connects the reservoir to the shock body itself. This ultimately means that the shock will never function properly. "

I'd take base model Progressives, Hagon or Works Performance.

Kidkawie wrote:

missionkz wrote: So... getting back to one of my questions.... what is an estimate in cost to have an old set of my Boge-Mulholland shocks rebuilt?

Try asking at Marks Swap Meet, lots of info on those shocks there.

I give that guy credit for trying to improve on those Ebay shocks. However, even if you can get one of those shocks to work, how long is it going to last? Did they hard anodize the shock body or use good chrome on the shafts? If not that piston band is going to wear out the inside of the shock body.
The site is a little confusing to navigate but I found some info on those reservoir shocks:

"Further analysis revealed that this damper, unlike the Model 1, is not a proper reservoir type shock. All of the parts are there to accommodate a functioning reservoir, though the manufacturer never machined the port that connects the reservoir to the shock body itself. This ultimately means that the shock will never function properly. "

I'd take base model Progressives, Hagon or Works Performance.

You've literally found the only post that doesn't apply to this thread. Good grief. The review you copy and pasted from was from and oddball model that I don't sell or endorse.

I have seen sets of RFY's with thousands of miles that show zero to no wear. Shocks aren't magic, they aren't rocket science, or even brain surgery. The materials may not space age quality in RFY shocks, but they are good enough. That's evident in the hundreds of satisfied customers I have provided my services to. The chrome quality is good, I haven't performed any Rockwell hardness test to confirm the quality, but I have never seen one wear either. The glide rings on the pistons are true PTFE (Teflon), they should last basically forever. If they don't I can laser cut new ones for literally cents. The linear bearing is a standard oil impregnated sleeve. These are the same materials used from Penske, to Ohlins, to KYB. No mysteries about these methods.

The review that applies to shock in question (aka the Model 1) can be found here. chrislivengood.net/wp/rfy-shocks-overview/

Further information here. chrislivengood.net/wp/rfy-shocks-technical-library/

Hagon and Works are great companies. I have nothing bad to say about them. But a standard emulsion shock can not compare to a well setup gas separated model. That's not conjecture, that's fact. And while there is an obvious and in some regards warranted stigma around Chinese produced goods, things are changing.

I got a kick outta seeing who the latest post author was, I use RFY shocks I modified (thanks to info furnished by yourself and crazy pj) and have to say they are just fine.

Don't knock it till you tried it

Chris_Livengood wrote: ....... a standard emulsion shock can not compare to a well setup gas separated model. That's not conjecture, that's fact. ....

But the question is who determines what is a "well setup gas separated model"? A crap shock is a crap shock regardless of the configuration. One with an undersized diameter rod (like the stock KZ shocks) can be counted on to have other shortcomings. A cheap shock is not going to stand the test of time and mileage, but a high quality shock will last a VERY long time with little or no performance degradation. So in my view it is far better to buy a shock that begins life as a quality shock than to buy a crap shock and try to convert it into a quality shock. I have used the stock KZ650 shocks when the bike was new and they were nowhere close to the quality of high quality aftermarket, high quality shocks such as Hagon or the old S&W shocks. To my knowledge there are no high quality shocks being manufactured in China, so to me it makes no sense to buy cheap Chinese junk and try to convert it to something worthwhile (like trying to make a silk purse out of a sow's ear), but to each his own. Ed

That data I have collected in the last three years is fairly conclusive, Ed. And while I'm are you have formed your opinions for good reasons, you are misinformed in this situation.

You also are misinformed regarding the manufacture of major brands in China as well as Asia. I ordered Showa brand bladders from Taiwan just two weeks ago, and know for a fact that many of their parts are machined there. Many of the springs found on popular brands are also wound in India. I also know that Showa seals, shims, and washers are Chinese made. I haven't studied the manufacture of many brands or products though, so I'm confident that other parts are procured from these regions.

As far as the stock shocks not being as good as the Hagons or S&W's, I'm confident you are telling the truth. Times however have changed and designs have changed as well. Your evaluation of 1977 equipment (or whatever year bike you have) really is only tangentially relevant. There is a reason why in most current vintage motorcycle racing you are barred from running reservoir type shocks, and it's not because they are disadvantage.

There is no "conversion" with my rebuilds. There simply is no need to. Instead, I assembly them properly and do my best to provide thorough inspection as well as customized setup. That includes damping adjustment, they have shim stacks, as well as length adjustment, and spring rate choice. The same options you get at Hagon, but in a more finite and tailored manor. In the end you get a more modern design as well.

Moreover, I have no inherent preference in this battle. I get lots of emails where I recommend Progressives, Racetech, Gazi's, Penske's, etc. instead of my own equipment. This isn't my job, it's not my livelihood. I do it for fun. I do it because I like to drink good beer, talk to motorcycle enthusiasts, and help people modify their bikes in rewarding ways. I have worked on many shocks in my 30 years, including shocks that cost $20k and up. Sure some are nicer than others, and lots of products have pros and cons, but one thing I will not do is ignore the data and facts. In this case, if you are looking for a modern design that has been proven reliable and cheap, there is no reason not to consider a rebuilt RFY shock.

What size is the piston and the shaft on those RFY shocks? I'm also curious about the inner workings of them. Maybe this is an incorrect supposition, but typically products like this start out as knockoffs of some well known product. What shocks are they similar to in terms of valving and general construction?

I would like to hear more about RFY shocks and what to look for in a good KZ 1000 shock.
Dave

Street Fighter LTD wrote: I would like to hear more about RFY shocks and what to look for in a good KZ 1000 shock.
Dave

Me too, this thread is starting to amass some good information.

Bowman wrote: This thread got me to do some shopping and I see I can get a pair of Gazi SL400300 for $400CAD including shipping, thats about $37.95USD I know someone else asked earlier upthread but does anyone know how good/bad these shocks are?

I've heard good about Gazi that's why I asked about them earlier too, they seem to have a good reputation in the classic bike publications. They definitely look classy, nicely finished.

If you ever worked on a $20k shock, if there is such a thing for bikes, even A kit Pro Ircuit units costs less, you would look at those Ebay shocks and laugh.

I have been reading this thread and thought I would ad my two cents if it's worth that. I have restored many Z1's and as a purist always used original shocks. They suck period!!! even the repo's. The best absolute upgrade you can do on your old kz is upgrade to a modern rear shock. I Never had a good "progressive "shock, Hagon shocks are pretty good and might buy a set for my next bike. The best are old koni special D's I had a set rebuilt by the konimon and you wont believe the difference they make on a bike. Expensive but worth every penny.
You can go to Hagon usa and get a good set for kz900/1000 $219 worth every penny just get the SS slime line's

my two cents
here is my every day bike , ride with konis