All The set of Forks I’ve brought for the Carbie 900SS Mongrel I’m building are a pair of Showa fully adjustable jobbies. These in fact: I had really good results with a Hyperpro Fork Kit on my M900, which has adjustable Marzocchi forks, so am going with the same idea on the SS. Trouble is, having looked at the Hyperpro catalogue I’m confused by the kits on offer. The Catalogue has three different kit numbers for the 900SS with Showa forks, dependant on what rear shock the bike originally came with. I can understand the Hyperpro Combi-Kit for both Front Forks and rear shock having a different part number, but why have three different part numbers for the kit that just covers the same set of front forks? Are the three rear shocks so much different that the Forks need to be set up so differently to match them? From the Hyperpro catalogue: MODEL YEAR........REMARKS..................FORK-KIT...............COMBI-KIT 900 SS `91-`96...SHOWA FR+RE..........SP-DU09-SSA001....SP-DU09-SSC001 900 SS `91-`96...SHOWA+WP SHOCK...SP-DU09-SWA001...SP-DU09-SWC001 900 SS `91-`96...SHOWA+OHLINS........SP-DU09-SOA001...SP-DU09-SOC001 The shock I’m going to be using is I believe an Ohlins from later 750SS. This one: So I could of course just order the kit that relates to SHOWA+OHLINS, but being me I really want to understand why the three different part numbers. Any suggestions? Thanks Nasher
The shock is a sachs unit not ohlins,the 3 options will be to cover the aftermarket rear shocks that are a popular replacment.
Thanks rcv4, but that suggests there may be no option listed in the Hyperpro catalogue for a bike with a standard rear shock. Nasher
I'd give them a call. If its just springs, providing same length then ohlins or sachs makes no difference
The rear shock shown is definitely the cheaper Sachs Boge one - however what is the governing factor for the rear shock is which swingarm it is fitted to. If it is the aluminium swingarm it must not have the Sachs Boge shock and rather the Showa one. This because the mounting eyes on the Sachs shock are significantly larger in diameter that the Showa - that means that the lower eye of the Sachs shock can't have the full rotation movement (sideways) as the eye hits the aluminium mounting lugs. Under a real thump of suspension, the lugs could break. If photos are wanted for proof let me know, but the Ducati info below should help.
Thanks Guys, looks like I'll need to mock all this up when I get time today and see what's what. I do plan to try and call them tomorrow(Monday) but am at work and sometimes find it difficult to make personal calls. An email to them Wednesday has gone unanswered so far. The NSS Mongrel, as it's been named by a colleague at work who thinks building a special involves bolting carbon bits to a standard bike less than 2 years old, will indeed use an Ali Swingarm, but I still have the Standard shock that came with the 600SS Donor I brought, so can use that if required. Just need to get some garage time today and will report back later. Nasher
It's a 900SS Ali arm that I purchased from a member on here, and has already had some mods done to it that I'm in the process of tidying up. I've had a play comparing the two shocks, I have and mocked them up to see what fits and what doesn't. Will sort out the images and write some text around them later. Nasher
Here's why Sachs Boge should not be fitted to aluminium swingarm. And yes, that purple spring is a Hyperpro - Sorry can't tell you the reference number, although it is the correct one.
Actually I can tell you which spring should be used on the Showa shock. According to Hyperpro: Reference Number SP-DU09-SSA001. That is the one for both 750SS and 900SS with fitted with aluminium swingarms and the correct OEM Showa shock. Not many 750s had the ally swingarm but a few certainly did as can be seen in the Hyperpro Spring list on their website.
This thread appears to be going off track a bit as I originally wanted to know about Hyperpro Showa front Fork kits, but the Rear shock stuff is interesting. These are the two rear shocks I have to use on my 900SS Mongrel. First the Sachs Boge unit that came with the 600SS donor I brought. Then the later 750SS Remote reservoir shock I brought on EBAY, also a Sachs Boge unit. Both actually fit in the Engine/Frame/Swingarm combination, but following on from Arquebus’s warning, and my physical findings, I can only use the 750SS Remote Reservoir one. The 600SS Sachs one can only go in one way up, as fitting it ‘Reservoir up’ means it touches the cam cover. So it has to go in this way up Unfortunately the lower end is then a very tight fit in the Aluminium Swingarm The 750 one goes in OK and fits all around. And has room to move at the top with respect to the Cam cover. I took the spring off and moved it through it’s full range to check. The difference in rotational movement can be illustrated so easily as below. The difference in the amount of movement around the bottom mounting is huge. First the 600SS Shock Then the 750SS one And showing how much movement there is by pulling the top of the shock to the side. So, I’m going to build the bike up with the 750SS remote Reservoir one, but keep any eye out for a different , read better, shock. My budget has already been more than blown on this build, so a new shock from the likes of Hyperpro is out of the question at this stage. Maybe I'll just fit a new Spring from Hyperpro as suggested by Arquebus I’ll try to call Hyperpro reference my original question tomorrow. Nasher
Neither of the Sachs Boge are suitable for use with the aluminium swingarm....... I'm pretty certain the Sachs Boge with the side mounted reservoir was fitted to the 600SS as well as being OEM on the 750......It was from 1996 onwards at least........but never in an aluminium swingarm. Hold either shock in your hand and pass the bolt through the lower eye.........now twist the bolt laterally and watch how the shock rotates on the bolt - when the shock is installed top and bottom it must be able to twist from side to side without the outer radius of the eye hitting the swingarm lugs. The actual 'stop' of the shock twisting too far is meant to end on the bolt, not use the lugs as a stop. In your last but one photo, looking at it exactly as you have it, rotate the shock clockwise and anti-clockwise.......don't pull it to one side at the top........if you tell me the outer radius of the eye doesn't touch the lugs, I'll shut up.
Mmmm, I'll have a look tomorrow evening. So, to make sure I've got this correct: What your suggesting is that in a thump to the suspension on a bike equipped with the Sachs Borge Remote Reservoir shock, the remote reservoir hanging out the side will resist and then gain momentum, spinning, or more accurately whiplashing, the shock about it's central axis enough that the lower joint will twist and spread the lugs on the swingarm the bolt goes through and break them. I can't think of another reason why the shock would twist about it's axis in use. I'm not doubting your knowledge, as you obviously have far more Ducati real life experience than me, but I'm surprised at this. Bearing in mind the central piston rod separates the remote reservoir from the bottom mount, and the bottom mount is only kept from twisting relative to the reservoir by the pressure of the spring on it's plates either end, I'd have thought the spring or plates would have overcome friction and moved relative to the body/Eye before enough force was generated to spread the lugs on the Swingarm. All this assumes the twisting force has not already been arrested by the steel plates on the frame stopping the top half of the shock from twisting. If the shock was mounted the other way up with the remote reservoir at the Swingarm end it would make far more sense that it could impart a twisting motion on the lugs. From what you are saying, I'd be safer using the 600SS Shock, as no twisting force is generated because there is no weight hanging off one side to gain momentum. Nasher.
Are you going progressive or linear front springs? Hyperpro do both IIRC. Very different feel and set up. Most of the DD boys have used std 600 shock with 900 s/arm no problem
Nasher - You are thinking too hard..........It is nothing to do with the reservoir, it is simply a rear shock needs to 'swing' about due to the nature of compression, rebound and torsional action of the spring - it's a coil , which will make it twist about. If Ducati recognised it (like what my earlier post shows) then why go against it? Imagine what would happen if a swingarm lug broke off after a hard bump at speed.
Bit of a habit of mine I'm afraid, overthinking things. I've realised I do have another option, and can't believe I didn't think of it before. When I get the SS finished and on the road I plan to put my Monster 900 back to nearer standard spec by taking the clip-ons off and going back to proper raised handlebars amongst other things, so I have two completely different types of bike. The monster will go back to being a bit more 'relaxed'. This is currently sat in the back of the M900: It's the right length, at 330mm, but currently has the Black Linear spring it came with when I brought it off Gumtree a year ago. It was less than £100 because of the Linear spring. It can't be set up that different for a Monster to an SS. I could try it with the linear spring in the SS, or I might be able to sell the two Sachs units for what it will cost me to buy a new spring for this, and I'll put the standard unit I took out of the Monster a year ago back in. Another question for Hyperpro tomorrow. Nasher.
Nasher, Dont mess around with these sachs units, get a standard Showa or, if you are upgrading the forks, get a better rear shock such as a Hagon, Hyperpro or Maxton. It'll be worth it. Ian
Mmmm, what a choice! Left to Right 600SS Sachs – 750SS Sachs – 900SS Showa – M900 Hyperpro Actually, not so much really. I decided not to compromise my lovely M900 by using it’s Hyperpro shock in the mongrel SS, so picked up a Showa 900SS shock that needs a bit of a tidy up, and will order a Hyperpro spring to compliment Hyperpro front springs. Does anyone know if there is anything about the Showa shock that will prevent me rebuilding it at home with new seals etc? I’m not a novice by any means, but a quick scan shows there is no obvious way to recharge it like the Sachs remote reservoir one that has a valve in the end of the canister. Nasher
I had my rear Showa rebuilt by Maxton a few years ago. At the time, they advised that replacement seals weren't available (we ended up making one good unit out of two). Don't know if that situation has changed (seem to vaguely remember a post somewhere about them being available now) - might be worth checking first, before opening up. Sent from my P01M using Tapatalk
