Rear shock options

discussions specific to the 906 Paso
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Kmamac
Posts: 93
Joined: Thu Jul 21, 2016 6:56 pm
model: 906 Paso
year: 1990
Location: UK

Rear shock options

Post by Kmamac »

I can no longer live with the ‘crash bang wallop’ of the very old and knackered marzocchi duo monoshock and need to do something (but can’t throw ohlin type money at it!
Searching through the archives it appears the shock is rebuildable (maxton maybe). My first question is, would a new shock, such as the relatively cheap Hagon be any better than a refurbished 30 year old design? I guess a refurb would be about£200-250? I think the Hagons are about £400 (No remote). If I went up to the next level, new Maxton I think I’m looking at £600? Is a new current shock that much better? keep going around in circles!
I’m not interested in originality I would just like the rear end do what it’s supposed to do when I’m riding hard during rides out. With only 88hp she gets a good thrashing and I like to keep her moving along on the twisty roads. I’m no expert on suspension but get the impression (rightly or wrongly) modern suspension is so much better. I also suspect the duo was actually a good unit in its day?
Front end will just have to do with a strip and new oil plus outer seals - should I put new springs in? Defo not going for new fancy insides as I think I’m looking at £1000!
Thanks in advance for all of your thoughts.
Tamburinifan
paso grand pooh-bah
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model: 907 I.E.
year: 1991
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Re: Rear shock options

Post by Tamburinifan »

88 hp is a bit optimistic...
Mail Rudy. info@duc-only.nl to see if he has any used Öhlins. Usually around 200€, well worth the money.
Gert

907 I.E. -91
M900 -97
MTS 1100s -07
Kmamac
Posts: 93
Joined: Thu Jul 21, 2016 6:56 pm
model: 906 Paso
year: 1990
Location: UK

Re: Rear shock options

Post by Kmamac »

Are you trying to tell me the factory lied about BHP when new, AND it’s lost some of them over the last 30 years? You have burst my bubble :lol:
Mc tool
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Re: Rear shock options

Post by Mc tool »

I pulled my duoshock apart and give it a good clean out .The oil was dark and dirty. The shaft and the rubber bellows were in good condition and the unit wasnt leaking any oil so I just stuck it back together with new Yamaha oil ( sorry , cant remember what weight it was ). It sure was worth the effort.
You mention banging and crashing your wallop which makes me wonder if you have enough air pressure in the shock as with out sufficient pressure it does clunk and bang and generally performs poorly. I found this out when one of my wanky mates let the air out halfway between the back of beyond and #ucking nowhere.
The front end will respond well to new oil too. My take on older suspension units that if they are getting a bit tired you could try slightly thicker oil than the factory specifies , even mixing 15 and 10 weight oils to get 12.5 ..... cant hurt , worked well on my Kwaka trail bike :)
I wish I was young again............Id be heaps smarter than last time
Tamburinifan
paso grand pooh-bah
Posts: 1527
Joined: Thu Jun 21, 2007 12:00 am
model: 907 I.E.
year: 1991
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Re: Rear shock options

Post by Tamburinifan »

Lets say the period 900 SS spec is bit more real at 73 hp... ;)

The Öhlins, although being from the 80`s just works and as good as on my MTS 1100s -07.
Gert

907 I.E. -91
M900 -97
MTS 1100s -07
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Frank.61
Posts: 264
Joined: Fri Jul 24, 2015 11:21 am
model: 750 Paso
year: 1989
Location: Belgium

Re: Rear shock options

Post by Frank.61 »

The 80-ties front fork is dated, although in it's days the MR1 Marzocchi fork was almost state of the art.
Modern forks do have cartridges which did not exist in those days.
Nevertheless with clean oil, fresh seals and (depending on your body weight) a set of Hyperpro springs it does work very well.
The rear on the other hand was (and to a certain degree still is) state of the art.
This for the construction as well as the shock itself.
Unfortunately after a few hundred were produced Ducati changed from the perfect Ohlins shock to a far from perfect (cheaper) Marzocchi unit.
If you have an original Ohlins I would suggest to rebuild it which is always worth the effort and money, provided that it is done professionally.
Only 1 but: if the shaft is damaged (hard chromed) it will not be easy since Ohlins does not supply the shaft anymore .....
These days there are TTX shocks (twin tube) which are an improvement over the "old" shocks but these are very expensive and only noticeably better under very hard use (superbike on track-like use).
The majority of the sport bikes still use the same technology as used in 1988 (the Paso was the first bike that used Ohlins as OEM shock supplier !!!).
The pressure (nitrogen gas) is necessary to prevent cavitation (foaming) which prevents the shock from damping correctly.
Bimota SB4-S - 1984
Ducati Paso 750 - 1989
Suzuki SV1000S - 2008
Ducati Monster 796 abs - 2010
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JWilliam
Posts: 331
Joined: Wed Oct 06, 2004 12:00 am
model: 906 Paso
year: 1989
Location: Nottingham, UK

Re: Rear shock options

Post by JWilliam »

I never thought the original Marzocchi rear was any good. I obtained a 750 Paso rear shock and that turned out to be far better. Adjustable preload too! A tight fit but it just about squeezed in, I made a bracket for the hydraulic adjuster and placed it where the damper control used to be.
Kmamac
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Joined: Thu Jul 21, 2016 6:56 pm
model: 906 Paso
year: 1990
Location: UK

Re: Rear shock options

Post by Kmamac »

Thanks for your comments. They have been extremely useful. I feel the marzocchi duo is getting closer to the bin! I will be looking into a new replacement. I will report back as to what I purchased and what I think of it.
Kmamac
Posts: 93
Joined: Thu Jul 21, 2016 6:56 pm
model: 906 Paso
year: 1990
Location: UK

Re: Rear shock options

Post by Kmamac »

Had a useful chat with Brook suspension here i the uK wrt new rear shock. Nitron don’t do a size that fits. YSS do specify one for the 750 paso. They have given me the dimensions but clearly it would be easier if someone wiser than me on this site could confirm they are the same dimensionally? From memory the 906 is heavier than the 750 but I guess they can allow for this???? We also discussed the Hagon but we’re both of the view they do not have a particularly good finish. If this (YSS) does work it’s also a low ish cost option as they are about 330 UKP
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Thebenelliman
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year: 1992
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Re: Rear shock options

Post by Thebenelliman »

I have a Hagon shock on my 907 it came with it when I bought it, I had thought about changing It but I think it performs quite well. I do enjoy a high speed ride and found it keeps the wheel to the road quite well. That said I have not experienced the original Marzocchi or Ohlins unit and I am no GP racer!
The Benelliman
1992 907ie
1981 Benelli 900 Sei
1989 Benelli 900 Sei
1976 Benelli 125 Enduro
1981 Benelli 250 2c
1976 Benelli 250 Quattro
1980 Benelli 254
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