90 900 Supersport Tidy-up

discussion about the 750 Sport and '89/'90 900SS, which share many mechanicals with the Paso series
The Paua Poacher
Posts: 69
Joined: Fri Jan 24, 2014 9:00 am
model: 900 SS
year: 1990
Location: New Zealand

90 900 Supersport Tidy-up

Post by The Paua Poacher »

Righto most of the parts are here so thought I would start a post so I could ask for any help as needed

Goal is to make this as close to original without any changes that cannot be easily reversed - just because I wanted this original (might do something very different in the future) - basically as a very young fella with japa 2 strokes at the time I saw the 1990 machine (old stock) sitting next to a 1992 model (latest release at the time) & whilst I knew they weren't fast & recognised the upside downers & updated fairings on the 92 .... it was the classic out-dated 90 model that I kept looking at

I know how flawed & unique this machine is now that she is stripped & ready for reassembly (have read a lot over the last year or so) … still happy with decision to buy & rebuild

Also a lot less skill required to do what I am doing rather than building a one-off with all the improvements & with no 4 stroke, non Japanese experience this suits me for now

In short I am no Mechanic … so help is good

Buying the Machine

The Mrs was away seeing her mother so after identifying a candidate for rebuild (after a lot of beer at 2 in the morning cause I could) took the 3.5 hour drive at 5am down the line to check it out (I thought I had the go ahead at that point but that is a long story) .. after a good look around the bike I took it for a quick spin … flat tyres, fork oil leaking everywhere, miss-fires & a little rain just to help … the guy asked me if there were any issues (nervously) & all I could say (cheekily) what you mean is there much right with it?

That said it was all there, straight & wasn't too f@@ked with so with intention to fully rebuild said I’d take it if it fitted on the ute (which I knew it would as have had half a house on the back of it over the years)

Stripped it on the back of the ute bagging a tagging as I went with photo’s (not enough photo’s) … threw in boxes to store at a mates place until I worked up the courage to tell the war department what I had done

While I waited for the go ahead I have worked on putting parts together … that was 15 months ago

So Far

The plan

Standard including paint … except for
K & N (for now as no airbox)
Open Pipes (for now as nothing in mine when I bought it … will see how loud)
High Comps (cause I can change anytime but should thicken mid range which is what I am after)

I would imagine I will go back to an airbox & baffles quickly if I don't like as only jetting will change

The Frame

After a good close inspection for any hairline cracks … all looks good so had sandblasted & in keeping with original have painted … to keep it tidy went down to the local VIN shop & replaced the tag (good of them to do) as looked a bit huckery next to the nice paint (been sitting for last 3 plus months so paint is nice & hard now)

Basically on the frame nothing to report … tidy example for age

If photo's dont show on this posting then will do when I work out how
Attachments
Frame B Painted 2.JPG
Frame B Painted 2.JPG (33.01 KiB) Viewed 12925 times
Frame A pre.JPG
Frame A pre.JPG (34.37 KiB) Viewed 12925 times
Frame A pre 1.JPG
Frame A pre 1.JPG (44.76 KiB) Viewed 12925 times
The Paua Poacher
Posts: 69
Joined: Fri Jan 24, 2014 9:00 am
model: 900 SS
year: 1990
Location: New Zealand

Re: 90 900 Supersport Tidy-up

Post by The Paua Poacher »

The Weber

Yes I intend to run the weber so have fully rebuilt … she is mint looking (at least) … I have used what was on the machine … interestingly has 116 stamped on the side … will work with it for now

The airbox had been hacked & as I haven’t found an original one yet I thought I would run a K & N …. I am not after revs on this machine (about torque) & all research I have says (no doubt I will be corrected here) no issue with power loss until looking for revs

The weber had been well badly treated (understatement) … only 3x bolts holding the carb & the ones there weren’t done up properly … a drill used to open up jets (way too much) … bent the float to drop fuel level in bowl (presumably attempt to correct flatspots) … seized so filled with CRC & forced to work … a real mess so explains the miss … the flatspots … & the sh!tty power (the engine was a different issue I will address later)

Soooooo hacked the spacer out of the airbox, shaped & tidied so I had a pattern for the CNC shop to shape me a replacement (you will see the shiny plate on the carb photo) … came back spot on except for minor dremel action where inserts in to the carb

I have no idea on the jetting but the very helpful weber guy said use standard, but up one on air jet as baseline & tune with the right gear once running

I wonder if my allumium plate will create or diminish icing? … would imagine more icing issues if anything

Attached Pics after rebuild ... the sh!tty choke cable was on the unit ... I have OEM replacement when I instal
Attachments
Rebuilt DCNF 44.jpg
Rebuilt DCNF 44.jpg (31.92 KiB) Viewed 12919 times
DCNF 44 with K & N Filter.jpg
DCNF 44 with K & N Filter.jpg (31.9 KiB) Viewed 12919 times
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englishstiv
paso grand pooh-bah
Posts: 1111
Joined: Wed Apr 09, 2008 9:57 pm
model: 907 I.E.
year: 1992
Location: Manchester, England.

Re: 90 900 Supersport Tidy-up

Post by englishstiv »

Good Luck gonna enjoy this thread I know. so keep us posted.
DUCATI 907ie 1992
HARLEY DAVIDSON ELECTRA GLIDE CLASSIC 1991
The Paua Poacher
Posts: 69
Joined: Fri Jan 24, 2014 9:00 am
model: 900 SS
year: 1990
Location: New Zealand

Re: 90 900 Supersport Tidy-up

Post by The Paua Poacher »

Still catching up on progress so far

Wheels

Standard 17" rims & were in not bad nic (old but low mileage machine so wear wasn't the issue on this machine which again was my preference when looking for a project) ... the only blemish was road rash on the front rim when it went down the road two owners ago which is why the machine had been sitting around for a few years (that same rash scarred the fork but that is a different post)

That said the excuse I needed to remove the rubber & bearings for tidy up

Had the road rash welded & shaped (I was going to shape with my trusty dremel but the mag place did it without me asking) ... great job as couldn't pickup where minor rash was & was in an area where the heat from the weld wasn't going to impact on the integrity of the rim (win win) ...

On researching one place was going to weld, shape & then paint (after etch primer) over the existing original powder coat ... but not my preference as whilst would have looked good now the etch primer was only going to be as good as the original powder coat ... lets face it powder coat only has a certain life as the aluminium will chalk up at some point (25 years old now)

So down to my sand blaster (gives nice surface the powder can take to) after cutting dowl to fit where the now old cush drives were & bolted ply over where the bearings sit (very snug so no blast impaired those surfaces underneath) ... clean as a 20 year olds landing strip!

Not all coaters are the same ... the guys i used spent time with me as I wanted areas masked & wanted the Zinc pre coat (which whether right or wrong was advised will also prolong aly applications) ... no matter what I wasnt going to etch & paint old powder coat no matter how good that appeared ... & was originally P coated (stand to be corrected there but looked PC) ... & for the rims just better wearing

Maybe someone can confirm Powder Coated with Zinc pre-coat correct application on Aly as well?
Attachments
Wheels Front & Rear.JPG
Wheels Front & Rear.JPG (27.46 KiB) Viewed 12886 times
Rear Wheel.JPG
Rear Wheel.JPG (28.43 KiB) Viewed 12886 times
Rear Wheel 2.JPG
Rear Wheel 2.JPG (24.67 KiB) Viewed 12886 times
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paso750
paso grand pooh-bah
Posts: 5558
Joined: Sun Jul 18, 2004 12:00 am
model: 750 Paso
year: 1987
Location: southern Germany

Re: 90 900 Supersport Tidy-up

Post by paso750 »

I enjoy restoration topics, too. :thumbup: Unfortunately they sometimes just end in the middle.
I do have an airbox from a 750S but it`s w/o the lid and 4 top plugs so it`s not worth the expense so send it to the other side of the world I guess. There`s one on ebay US but it`s missing the snorkels.
The airbox of the Paso 906 is the same btw. The one of the P750 isn`t. It would probably fit as well but the crankcase breather hose is connected to the front of the airbox while on the Sport/906 it`s on the bottom.

With HC pistons you should use other spark plugs. NGK - DCPR9EA-9 or equivalent.

Being curious how small is the gap between the intake snorkel and the top of that K&N filter?
the very helpful weber guy said use standard, but up one on air jet as baseline
this makes me wonder. I don`t know how that K&N affects the a/f mixture but if your exhausts are empty the engine definitely will run lean.

G.
The Paua Poacher
Posts: 69
Joined: Fri Jan 24, 2014 9:00 am
model: 900 SS
year: 1990
Location: New Zealand

Re: 90 900 Supersport Tidy-up

Post by The Paua Poacher »

Noted on Spark ... will ask a few more questions once I get to engine as really unsure what to retard timing to for baseline with JE standard High Comps 11.5 / 1 ....

Snap on clearance to top of filter ... believe will be close ... very close but again haven't started assembly

And yup reckon lean ... but Mr Weber reconed OK to start with with a note tuned before any loading
The Paua Poacher
Posts: 69
Joined: Fri Jan 24, 2014 9:00 am
model: 900 SS
year: 1990
Location: New Zealand

Re: 90 900 Supersport Tidy-up

Post by The Paua Poacher »

Triple

Just wear so blasted & painted with the hardest automotive flat black I could ... came up nice

Clip-ons

Were a different story in that the bike had some shocking aftermarket crappers that had no risers so the crappy lock to lock on a 900ss wasnt even reached as the clip-ons wouldn't allow (when I test road I did a 6 point turn ... not the awesome 4 point turn we should get)

Finding original clip-sons was a mission & after finding some at a wreckers 1000 kms away had sent up ... was told pretty ropy condition but when I opened the packet they were both bu@@ered ... the bars were both bent & so bad they had broken the welds (very bad)

The wrecker felt bad enough to throw 20% refund in cash in the package ...really were throw away

Anyway used the same welder that did some other work ... stringlined & welded in some new bars (took a while as he had to order in the right material)

I show a closeup of the weld ... that was very nice

Sandblasted & Painted with same automotive flat black

Sidestand

Awesomely bad design ... but standard it is ... blasted & painted

Forks are with sidestand but that is a different post as haven't put together yet as still trying to find new internal smaller bushes for the M1BB (I have larger internal bushes from Steins) - if anybody knows where I can get these stanchion bushes from would be bl00dy good

Serious road rash had ground out the bottom of the fork ... again welded as the rash was on a thicker part the weld didn't impact on the internal integrity ... then shaped on my dremel before blasting & painting ... came up good
Attachments
Clip-ons.JPG
Clip-ons.JPG (20.3 KiB) Viewed 12850 times
Clip-ons (Welds).JPG
Clip-ons (Welds).JPG (26.42 KiB) Viewed 12850 times
Triple & Sidestand.JPG
Triple & Sidestand.JPG (25.77 KiB) Viewed 12850 times
The Paua Poacher
Posts: 69
Joined: Fri Jan 24, 2014 9:00 am
model: 900 SS
year: 1990
Location: New Zealand

Re: 90 900 Supersport Tidy-up

Post by The Paua Poacher »

Closeup on Clip-on weld
Attachments
Clip-ons (Welds).JPG
Clip-ons (Welds).JPG (20.56 KiB) Viewed 12850 times
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paso750
paso grand pooh-bah
Posts: 5558
Joined: Sun Jul 18, 2004 12:00 am
model: 750 Paso
year: 1987
Location: southern Germany

Re: 90 900 Supersport Tidy-up

Post by paso750 »

nice work.
The 41.7mm bushes for the Paso can be found from BMW. BMW also had numerous bikes with 40mm stanchion tubes so I`d try to take your old fork bush and visit a BMW motorcycle dealership if there is one around and ask the guy from the parts desk if he has something like that. Maybe you`re lucky.
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ducinthebay
paso grand pooh-bah
Posts: 1323
Joined: Sat Sep 03, 2005 12:00 am
model: 750 Sport
year: 1990
Location: SF Bay Area

Re: 90 900 Supersport Tidy-up

Post by ducinthebay »

Yeah, the M1BB is a 40mm fork, so the Paso bushings won't work for it. But then again, I really can't say, as the 900SS was a very rare beast indeed.

Nice progress none the same. Wheels look great.

I find the side stand wayyy too short, and have added length by using a toe brake from a roller skate to the bottom of the stand. Works wonderfully. Straightens up the bike, widens the footprint on hot pavement so it doesn't sink in, and even saves your ass if you forget to take up the stand after a stop. (i have a bad habit) Drill and tap a 6mm hole, and use some loctite.
Image

Cheers,
Phil
Duc in the Bay
1990 750 Sport x2-Rosso Blanko (900ss copy) & Nuovo Nudo (Scrambler project)
1991 907 -mostly stock
2002 ST4s - Lots of mods.
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paso750
paso grand pooh-bah
Posts: 5558
Joined: Sun Jul 18, 2004 12:00 am
model: 750 Paso
year: 1987
Location: southern Germany

Re: 90 900 Supersport Tidy-up

Post by paso750 »

I sent an online Duc parts shop (http://www.duc-store.de/epages/15495490 ... 2F15495490) a short mail yesterday asking for #34910061a (fork bush) and they can get them in a week time. Price is €17,90 ea.
If they can get them I guess a local Ducati dealer can get them as well.

G.
The Paua Poacher
Posts: 69
Joined: Fri Jan 24, 2014 9:00 am
model: 900 SS
year: 1990
Location: New Zealand

Re: 90 900 Supersport Tidy-up

Post by The Paua Poacher »

Thanks duc750 .... I have sent an email to Duc store .... Must admit haven't tried to hard locally yet but struggled to find up to this point

Cheers
The Paua Poacher
Posts: 69
Joined: Fri Jan 24, 2014 9:00 am
model: 900 SS
year: 1990
Location: New Zealand

Re: 90 900 Supersport Tidy-up

Post by The Paua Poacher »

Back to the Wheels

New Bearings installed
New Cush Drive bushes installed
New Michelin Pilot Power 2 installed (got a reasonable deal on a tyre that will out perform me)

Just waiting replacement bolts before torquing the disc's back on

White looks good in a showroom but keeping clean is another thing ... in keeping with standard it had be done & doesn't look bad
Attachments
Bearings Cush Drive & Mich Pilot Power 2.JPG
Bearings Cush Drive & Mich Pilot Power 2.JPG (31.88 KiB) Viewed 12752 times
Disc back on.JPG
Disc back on.JPG (36.27 KiB) Viewed 12752 times
Mc tool
paso grand pooh-bah
Posts: 1873
Joined: Wed Dec 05, 2007 12:35 am
model: 906 Paso
year: 1990
Location: Newzealand

Re: 90 900 Supersport Tidy-up

Post by Mc tool »

Hi Paua , I have a bunch of SS (97) parts for sale on TM ( Hamsav ) ,just thought Id let you know there is a discount for Ducatipaso members :D ( I have air box snorkels ) :cool:
I wish I was young again............Id be heaps smarter than last time
The Paua Poacher
Posts: 69
Joined: Fri Jan 24, 2014 9:00 am
model: 900 SS
year: 1990
Location: New Zealand

Re: 90 900 Supersport Tidy-up

Post by The Paua Poacher »

The Crank

I have half posted in Small End Enquiry but to keep thread together fill the spaces

While all the other stuff bubbling away I had the Crank Balanced, etc, etc

Bottom End
Small End (Nissan GA16/RB4107 19x22)
High Comps going in 11.5:1 JE's (whilst a standard build these can be changed anytime)
New Bolts
Oil Gallery replaced (Locktite & particularly asked to be staked)
Balanced to 52%
Polished

The Engineers List

REMOVE CON-RODS FROM CRANK.
REMOVE 2 X LITTLE END BUSHES FROM CON-RODS. MEASURE NEW BUSHES,
FREEZE FIT NEW BUSHES TO CON-RODS, DRILL OIL HOLES, HONE BUSHES
TO SUIT GUDGEON PINS. CLEAN, ALIGN CON-RODS, FIT BIG END
BEARINGS TO CON-RODS, CHECK CLEARANCE IN SPEC. & REMOVE BEARINGS.
BALANCE 2 X PISTONS, 2 X CON-RODS, SET UP BOB WEIGHTS, BALANCE
CRANK 52%, POLISH CRANK.
REMOVE OIL PLUGS FROM CRANK, ACID TANK CLEAN CRANK.
FINAL CLEAN CRANK, FIT OIL PLUGS, LOCKTITE STAKE OIL PLUGS, FIT
RODS TO CRANK.

Very comfortable with that as knowing a few people up with Machinery reinforced this shop is very good
Attachments
New Oil Gallery Staked & LT.JPG
New Oil Gallery Staked & LT.JPG (30.21 KiB) Viewed 12657 times
Balanced Crank.JPG
Balanced Crank.JPG (35.19 KiB) Viewed 12657 times
Small End Bushes Replaced.JPG
Small End Bushes Replaced.JPG (29.63 KiB) Viewed 12657 times
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