1981 SD900 Darmah - Restoration Project

Post pictures of your twin cylinder Bevel Drive Ducati (pre-1985) along with a description here.
pilotg
Diana
Posts: 51
Joined: Sat Mar 19, 2011 12:24 am
Location: Christchurch, NZ and Brisbane, Australia

1981 SD900 Darmah - Restoration Project

Post by pilotg » Sat Mar 26, 2011 12:25 am

I took delivery of a 1981 Darmah yesterday. It was originally an SSD 900 in Black/Gold but was changed by a previous owner to the current purple. Not my ideal color but there we are. I'll try to attach some photos.

It also has been fitted with clip on bars and a grey seat.

There is quite a bit of work to do even to get it registered, a little more than I thought to be honest. Anyway, we're on our way. It's my first Ducati and I'm both excited and a little frightened.

First problem has been starting. The battery was almost dead when I got it so I checked the levels and charged it overnight. I drained the fuel and put in 5 litres of fresh 91 petrol. After a couple of coughs away she went although not a steady idle. After a minute or so I let it stop. I started it again and then left it for an hour or so to see if the battery would hold it's charge.

So far so good. After the one hour wait I tried to start it again. Cough cough cough then loud bang, smoke from the right carbie (38mm Dellorto) and now the starter spins without the engine turning over.

I've checked through most of the forums re Darmah starter problems and my best guess is that the Sprag Clutch has gone.

First question is, am I right? Second question, if I'm not right, what can I do? Third question, If it is the Sprag, is it something I can do myself (not a mechanic but fairly careful about following good practice and instructions).

This Sprag business seems to be quite a weak point. The current one in my machine was apparently changed a year ago when the enine had a complete rebuild, along with the carbs. Can it have gone so easily so soon?

I'm located in Timaru, South Island of New Zealand and no idea what resources are available to me.

I plan to keep a blog going through this restoration and would really appreciate any advice/help anyone feels like passing my way.

Great website, by the way.

Many thanks [img]

http://www.flickr.com/photos/21807291@N00/5560198623/
1981 SD900 Resto project

johnnyb
Mariana
Posts: 25
Joined: Thu Jun 11, 2009 3:58 am
Location: Sydney Australia

Post by johnnyb » Sun Mar 27, 2011 12:05 am

hello,

Great to hear you have jumped into the bevel world. Once you get it sorted you will have many great days ride (and many nights tinkering ;-)).

Yes the sprag is a weak point (and expensive) and yes it sounds like you have killed yours. Biggest killer of a sprag is a back fire. The back fire rotates the engine backwards killing the sprag. To be fair the sprag will last but only if the bike is running and tuned well. Now that the sprag is dead dont be temped to push start the bike because the sprag could be broken in bits and those bits can work their way into the guts of the bike if you start the engine.

Replacing the sprag can be done yourself if your ok with the tools. There are a couple of tricks such as getting the flywheel off the tapper but once you do the job once it quite easy. There is plenty of good info regarding the sprag clutch and replacing one on this forum, just do a search.

cheers
John in Sydney Australia

Darmah 900sd
900ss

User avatar
BevHevSteve
SITE OWNER
SITE OWNER
Posts: 2133
Joined: Wed Mar 10, 2004 8:53 pm
Location: Lafayette, California
Contact:

Post by BevHevSteve » Sun Mar 27, 2011 7:17 am

http://shop.bevelheaven.com/detail.aspx?ID=67
I have sprag bearings in stock and they are not too difficult to replace. Once you do, keep thebattery fully charged and the engine in good tune. It is very important to rebuild your carbs (replace all the soft bits) then sync the carbs correctly to help avoid backfires. Keep a light thumb on the starter button! Ok, I will have a look at your photos and see about posting them directly on the site on Monday if I have the time. Thanks.
Image
Steve Allen (925)798-BEVL[2385] Ride'm, Don't Hide'm
Ducati/Euro Spares -> https://Store.BevelHeaven.com
Facebook > http://facebook.com/Bevel.Heaven
Twitter > http://www.Twitter.com/BevelHeaven

pilotg
Diana
Posts: 51
Joined: Sat Mar 19, 2011 12:24 am
Location: Christchurch, NZ and Brisbane, Australia

Time machine....

Post by pilotg » Fri Apr 08, 2011 11:34 pm

A week or so ago I posted about finally getting the bike to run. But that really wasn't the story. What took place was truly miraculous..

When I saw the bike on the web auction I was not that impressed as the color is horrible. It was probably the reason why the bike hadn't sold and was being offered at a reduced rate. I could see from the photos that the 'bones' looked good but as the bike was at the other end of the country I had to take a bit of a gamble.

After the bike was payed for and before delivery the previous owner let me in on a few 'extra' problems. The front master cylinder was shot and the rear brake system complete needed to be rebuilt. Add to that, paint, seat recover, speedo cable, indicators, etc etc... It was all starting to add up.

A week later it rolled off the transport and whilst I was still excited, my heart did sink a little. It sank further when it wouldn't start. As described before, I took the logical approach and changed the fuel and recharged the battery.

With a great deal of trepidation and fear I pumped the ticklers, gave the throttle a couple of twists and with somewhat of a grimace, touched the start button....

What happened next was, as I said, miraculous. With that first 'gthump gthump gthump' I was transported 11,000 miles and 30 years back to my youth. I could see that fellow student standing casually next to a 78 SD900 in the warm glow from the Chinese restaurant window where we would gather after kick out from the pub. I could even smell the greasy spring rolls and I'm ashamed to say that I actually giggled. How sad is that, a man of 48 giggling in the shed. There is no hope... :-)

After a few minutes I shut her down as I have two elderly ladies as close neighbors and I was worried about the racket I was making. Immediately I was back in New Zealand in 2011. Time for tea and a chuckle....

As you know, the next bit was distressing and expensive. I blew the sprag. We live and we learn.

Next time I'll tell you about the reaction from the old ladies next door.

In the meantime the sprag has arrived from Steve along with a few other essentials, the brakes are off being serviced and I've changed those horrible clip ons to standard Darmah bars.

Till then, all is good here in the shakey South Island.
1981 SD900 Resto project

User avatar
BevHevSteve
SITE OWNER
SITE OWNER
Posts: 2133
Joined: Wed Mar 10, 2004 8:53 pm
Location: Lafayette, California
Contact:

Post by BevHevSteve » Sat Apr 09, 2011 1:28 pm

Hi George, you need to enable sharing in your flickr account to be able to post your photos here or anywhere.......
Image
Steve Allen (925)798-BEVL[2385] Ride'm, Don't Hide'm
Ducati/Euro Spares -> https://Store.BevelHeaven.com
Facebook > http://facebook.com/Bevel.Heaven
Twitter > http://www.Twitter.com/BevelHeaven

pilotg
Diana
Posts: 51
Joined: Sat Mar 19, 2011 12:24 am
Location: Christchurch, NZ and Brisbane, Australia

Sharing...

Post by pilotg » Sat Apr 09, 2011 5:13 pm

All fixed Steve. Sorry about that. Have you any experience using a Dremel tool with a stainless brush for cleaning/buffing aluminum?

Regards G
1981 SD900 Resto project

pilotg
Diana
Posts: 51
Joined: Sat Mar 19, 2011 12:24 am
Location: Christchurch, NZ and Brisbane, Australia

Carbs....

Post by pilotg » Sun Apr 24, 2011 7:08 pm

I read frequently on these pages about PHF and PHM, 32mm, 40mm and occasionally 36mm. My Darmah has 38mm PHMs. Would these have been standard? I thought they all came out with 32's and were fitted after market with 40's to improve performance?

My engine number is 905917, and frame 951904.

I was told by the previous owner that it was originally a SSD but has been corrupted into its current form., neither SSD nor SD.

If it was originally fitted with 32's would I be doing the bike a favour going back to those? I'm yet to take them apart so can't advise on the components or settings. When I do I'll be looking for some advice about how to set them up prior to tuning.

Many thanks
1981 SD900 Resto project

User avatar
Craig in France
Cagiva Elefant
Posts: 833
Joined: Tue Mar 23, 2004 3:58 pm
Location: Montpellier, France

Re: Carbs....

Post by Craig in France » Mon Apr 25, 2011 5:20 am

pilotg wrote:My Darmah has 38mm PHMs. Would these have been standard?
No.
pilotg wrote:I thought they all came out with 32's and were fitted after market with 40's to improve performance?
Some bikes sold in some markets came with 40s as standard; but generally, 40mm carbs were part of the racing upgrade that included Conti silencers, high lift cams, bigger valves etc.

"Improve performance" is a debateable concept :) . 40s will give you more top end speed, but will cost you a little in low end tractability.
pilotg wrote:My engine number is 905917, and frame 951904. I was told by the previous owner that it was originally a SSD but has been corrupted into its current form., neither SSD nor SD.
At 905917, your engine number is a bit later than the last number that Ian Falloon suggests for the SSD production run - he lists 905850. But your frame number is inside - Ian gives 952820 for the last SSD. So you're on the cusp ...

What seat do you have? Whale tail, or the 'ugly but more comfortable' version?
pilotg wrote:If it was originally fitted with 32's would I be doing the bike a favour going back to those?
See earlier comment - really depends on what you want from the bike. Partly on the grounds that any modern 600 can blow an old Dramah into the weeds anyway :lol: , I stick with 32s ... Steve A. reckons 36s are a good compromise.

Ciao

Craig

pilotg
Diana
Posts: 51
Joined: Sat Mar 19, 2011 12:24 am
Location: Christchurch, NZ and Brisbane, Australia

Post by pilotg » Tue Apr 26, 2011 1:49 am

Wheels.....

This bike has 6 'double' spoke wheels with FPS cast into the rims. They have been painted silver at some point but this is now coming to the end of its life. There is the odd spot where the paint has bubbled. When these bubbles are rubbed they are full of white powder. Apart from this they appear to be in good condition.

In some of the other posts I read that there can be problems with these cast wheels. What's the consensus on FPS?

Am I safe to get these blasted and resprayed in gold? Some wheels I notice have an unpainted rim. What's the pro forma on that one?

I once saw an SD900 with wire wheels and was surprised at how I wasn't appalled but I haven't seen a single one in these pages.

Any opinions/advice welcome.
1981 SD900 Resto project

rwhc80
750 GT
Posts: 174
Joined: Sat May 16, 2009 6:19 am
Location: Melbourne Australia

Post by rwhc80 » Tue Apr 26, 2011 7:32 am

pilotg,

The FPS rims are fine, so go ahead and have them done. In fact they are getting hard to get so hang onto them.

The earlier speedlines and campos did have some problems with cracking and were replaced by the later FPS that you have.

Up to you re the spoked rims, personal choice.

Regards
Rick
I have desmo disease, I just hope they never find a cure !!!

pilotg
Diana
Posts: 51
Joined: Sat Mar 19, 2011 12:24 am
Location: Christchurch, NZ and Brisbane, Australia

Post by pilotg » Wed Apr 27, 2011 12:58 am

Thanks Craig. Having read quite a few posts I thought you might be the one to have the right answers! Much appreciated.

On the carb front, budget restrictions are going to dictate that I stick with the current PHM 38's for at least the next 12 months, so I'm going to have to learn how to set up and tune them well, fast.

After that I'll probably go down to 32's. Some friends are encouraging me to head down the Mikuni route. I'm too inexperienced to know which way to go.

This poor old bike has had some terrible things done to it in its thirty years. Without knowing what it was originally it would be hard to restore it totally. However, that said I plan on at least making it respectable, which at present, it is not.

Thanks once again.

Regards
1981 SD900 Resto project

pilotg
Diana
Posts: 51
Joined: Sat Mar 19, 2011 12:24 am
Location: Christchurch, NZ and Brisbane, Australia

Post by pilotg » Wed Apr 27, 2011 1:06 am

Phew! That's a relief. FPS are OK. Having found a few sins I didn't know about when I bought the bike it was nice to have a good result for a change.

rwhc80 I really appreciate the input.

Best regards
1981 SD900 Resto project

User avatar
Craig in France
Cagiva Elefant
Posts: 833
Joined: Tue Mar 23, 2004 3:58 pm
Location: Montpellier, France

Post by Craig in France » Wed Apr 27, 2011 3:04 am

pilotg wrote:Thanks Craig.
No worries.
pilotg wrote:On the carb front, budget restrictions are going to dictate that I stick with the current PHM 38's for at least the next 12 months, so I'm going to have to learn how to set up and tune them well, fast.
No probs sticking with the 38s, especially, as you say, seeing as you've got them. As to tuning, the main thing (IMO) is to make sure they are really, really clean before you start fiddling. In particular, the drilling that provides air to the idle circuit is very prone to getting partially blocked. You think it's 100% clear, but it isn't. And then you've lost the war before it even started.

Have a look at the Dell'Orto manuals here:
http://www.filejumbo.com/Download/45CA6EEFE1C3FECE

http://www.filejumbo.com/Download/3411105C8A58D60D

As to jets etc, I'd start by comparing what you've got now with the standard settings for a 40mm carb. I'd be surprised if they'd be that different, especially as regards the all-important pilot jet. Here is what Ian F. lists for various carbs and applications, for instance. As you can see, apart from the mains, there aren't a lot of differences:

Image
pilotg wrote:Some friends are encouraging me to head down the Mikuni route. I'm too inexperienced to know which way to go.
These friends wouldn't be members of the Oz Laverda Mafia by any chance -?!
Nowt wrong with Mikunis. They're a better (later, simpler) carb than the Dells. But unless you're really into tuning and fiddling, I'd put this one on the back burner.

Once last thing: you didn't say what kind of seat the bike has ....?

Ciao

Craig

pilotg
Diana
Posts: 51
Joined: Sat Mar 19, 2011 12:24 am
Location: Christchurch, NZ and Brisbane, Australia

Post by pilotg » Wed Apr 27, 2011 11:04 am

All great advice and info, thanks. I downloaded the Dellorto manuals a week ago and have been skimming through them but will leave the serious study until after I've fixed the sprag.

The bike has currently a flip up tail. Now, I know I'm going to get some flak for this but.... the seat is buggered. It's been recovered 20 years ago in light grey vinyl. I'm sure when it was new it looked OK especially with the new purple paint (!) but it's sad and saggy now. I had plans to get it recovered, and will still do that later but in the meantime I picked up an original new whale tail seat for less than I thought. I can also get a new fibre glass whale tail base locally (Australia). As the whole body is to be resprayed in a months time anyway I thought I would change that aspect of the bike. I have always preferred the whale tail look, despite my 'friends' comments that it questions my sexuality. I can live with that. So, hopefully I'll be able to choose which look I prefer on any given day.

Slightly odd question....any idea what the original handlebar width was? I bought and fitted a new handle bar but it looks a little wide. I'm guessing an inch too big each side.

I've been studying all the photos I can to see where all the cables and wires lead around the forks, dash, tank etc. It's a mess right now and I would like to sort it out.

I'll be in NW Scotland for two weeks at the start of June and later in Normandy visiting my sister. During that time the body work will be done. I'm going jet black with the gold trim.

Thanks again
1981 SD900 Resto project

pilotg
Diana
Posts: 51
Joined: Sat Mar 19, 2011 12:24 am
Location: Christchurch, NZ and Brisbane, Australia

Disc rotors......

Post by pilotg » Sat Apr 30, 2011 12:55 pm

The latest discovery is the disc rotors. Front and back they are at or below the 5.8mm minimum thickness. Bugger!

From what I can see the replacement is going to cost me around $750 to $1000 as I need all three rotors. There really is nothing else to do. I have emailed the guy that sold me the bike (sight un seen on the internet from the other end of the country - lesson learned there) and asked for his comments. I can guess what they might be .

This brings me to a not unreasonable question, considering my inexperience. Loctite... I'm thinking the bolts holding the rotor to the hub to the bike should be locked with Loctite. Right? And there is more than one colour/type. What colour where? I'm about to tackle the sprag bearing in the next week or so. How do I know when and where and what to use?

Second lesson I think is whatever your budget, double it!

As usual, all feedback welcome.
1981 SD900 Resto project

Post Reply

Return to “Bevel Head Twins Photo Gallery”