1980 900SS rebuild...

[Vacant Possession]

Series Regulator fitment

After a catastrophic regulator failure on my GTS, I decided to replace both of the bevel's regulators. I chose to use series regulators rather than shunt to molly coddle the windings. So for the GTS, I went for a Shindengen 775 as it's quite a bulky unit, but the GTS has room.

Apart from failure, there is another reason I wanted to install a thoroughly modern regulator - I wanted to start using lithium irn batteries in my bikes and I wanted the best protection I could have for them. (Think avoid a fire ).

For the SS, I went for a Compufire 55402 3 phase series regulator which looks quite like the OEM part - although it's black.

To make this fit, I had to chamfer the fins otherwise they would have fouled the side panel. For me, being black meant I was able to hide my crimes with a spray can .
Under the seat looks like this:

I have had no problems so far, I fitted the regulators a couple of years ago and am hoping for at least forty years out of them .

 

[West Cork Paul]

Great thread

 

[Vacant Possession]

Great thread

Thanks Paul!

I don't have a modern bike and am quite frustrated I can't get out whilst there is salt on the road - so I am consoling myself with getting the bikes ready for the good weather. Both bikes are due for engine drops, the SS because I have my spare set of heads re-shimmed and the GTS as I am going to stove enamel the frame black and fit the new centre stand. The GTS *might* have a cracked ring (or worse) on the rear cylinder and I want to have a look.

I might even clean the SS whilst the engine is out. I am currently running an original OEM 2 into 1 Conti system on the SS, and I am going to refit the dual Conti's, even though the 2 into 1 sounds identical, fits perfectly and is much simpler. I have never seen another 2 into 1 Conti system. The silencer is a little larger than the normal ones, but otherwise the same construction. You can (sort of) see it here:

I am considering looking at a proximity detection solution for the neutral light switch, as the gear position cam wears. The OEM neutral light switch arrangement is pretty naff.

That should keep me busy for a while .

 

[Vacant Possession]

Wiring both the old & new dashboards - Contd.,

Here is the back of the SS dash circa 2012, converted to LED indicator lamps. As you can see, it was speed over compatibility and I had to adapt the loom and add a start earth point - all non-standard.

I had a lot of trouble finding suitable crimp ring terminal with a male 6.35mm spade, the original item bigger than 11mm and smaller than 12mm. I suspect it's 7/16". I gave up and bought 10mm sturdy brass ring terminals from fantastic kojacat and also eBay, together with 45 degree 6.35mm & 4.75mm male spades.

I had to manually drill the ring terminals up to 11.5mm, I modified the male spades and soldered them to the ring terminals for a Fanny Craddock 'here's one I made earlier' moment:

Because the original loom was designed to go with an original dash, the next bit was pretty easy and here it is done. It just plugs straight in to the existing loom and I think is a huge improvement over my initial 2012 'let's get out riding it' solution. Here is the original dash & with its original indicator lights, all now super bright LED's with new gel filters. The LED's are also colour specific for extra hue intensity.

Now for the new dash...

Right then, the original dash lights earthed through the holder, the new LED dash lights (sourced a long tiome ago) have flying leads for +ve & -ve. The implications for the wiring might not be on top of one's mind when temptation sets in and that buying finger gets itchy .

Ho hum.

That's why my first quick stab was a cacophony of wiring. It was a mess, albeit tidy, but still a mess. It also suffered a fracture at the interface between the substantial main loom wiring and the delicate LED wiring. It had an odd (but effective) star -ve terminal.

Bearing in mind access to change the LED's with the modern LED indicator lamps is only from the rear, I wanted to be able to easily unplug individual lamps & change LED's. Yes, LED's or the resistors do break from time to time.

My plan was to build a custom terminal block, decoupling the old 6.35mm spades from the micro wiring from the LED's, and implement visually easier to follow wiring, similar to the original method. I chose the smaller spades for the very thin wire from the LED's, I didn't want to break the wire when removing a spade when changing an LED.

I love Tufnol! Easy to work with, cheap and a great insulator.

I bought some countersunk 4mm Allen screws, and I was away. Putting all the terminals together was a bit fiddly but with the upgraded LED's achieved my main goals or reliability, availability & serviceability. I haven't yet attached the terminal block to the dash - I might use silicon or do you have a better idea? I'd like to lock the bases of the terminal in something like potting compound.

I have some super bright coloured LED's and am awaiting some of the tiny 3mm long 580R resistors to turn up, then the new dash/indicators will receive a colour & intensity upgrade/blast.

Here is the original dash, with a new sub loom. I was going to hack one of the looms to include an ignition pulse lead for the new Smith's Classic tachometer but I have decided it will be in it's own small sub loom.

I will modify the standard rather messy coil/Bosch transducer sub loom to permit the attachment of an electronic tachometer, but that's for another post. TTFN!

 

[Vacant Possession]

I do have flag terminals which would have been better for the rear of the dash, does anyone know where one can buy a crimp tool for something like this?
Edit: Found it, here

 

[Vacant Possession]

Hydraulic clutch conversion, Part 2.

I was really unhappy with the slave cylinder I used for my previous post converting the SS to a hydraulic clutch. It had the following problems:

• the banjo junction was a long way forward, fouling the fins when fitting
• not enough movement, max 10mm of piston travel not allowing any room for slack
• it leaked with new washers, then leaked again with new annealed washers

In software we'd call what I have done 'refactoring', so here we go with Mk 2 in my agile build to 'continually deliver valuable enhancements to my old bevel Ducati'.

It all starts with the Tony Brancato's extended replacement clutch arm. Looks like Tony's site has gone down. I hope he is OK and has just retired; he's a lovely skilled man.

This is my bike a few years ago, with Tony's arm; it's longer than the standard making the clutch action lighter, but moving the plates less.
Note: that as a result of the extra length, cable is bent up at an angle.
The standard arm is quite a lot shorter.
Note: with the standard arm, the cable is bent down.
Neither of these are conducive to a long life for a hydraulic slave cylinder, we need a straight pull; so I shorten the excellently made Tony Brancato arm and alter the angle of the nipple holder to make it straight too. I have covered this elsewhere, this is the reasoning behind the change.

So I set about finding a better inexpesive alternative to what I had, as good as the Frando slaves available from Venhill at £120 a pop inc. VAT. Frando are good, that's what's on my GTS.

I bought three different types from AliExpress, including the one I had previously fitted; however only one was worth having and in my opinion is even better than the Frando. This is the one and here it is prior to fitting:

Adding a 25mm aluminium spacer and a 10cm threaded rod gives the perfect length; there was no need to cut the threaded rod.

This slave cylinder has an interesting design, with the following benefits:

• rather than the piston being directly attached to the threaded rod coming out of the cylinder, the unit has a hole straight through the centre through which a long screw passes. There is an extra internal 'O' ring to seal/allow this.
• the banjo hole is further back on the body making fitting without fouling the fins straightforward
• it's a bit bigger, but that's OK
• it has a longer pull, in excess of 16mm
• nicely made

I have one complaint. The supplied nuts are not 13mm but 14 or 15; I swapped these out as there isn't much space for a spanner with 13mm, and I already have a specially (and brutally) ground spanner to fit 13mm.
Here it is fitted; and it doesn't leak. The clutch has great feel and pulls the same distance as the Frando, about 10mm - directly in line with the slave cylinder piston.

I can even imagine either a) holding in the clutch at traffic lights for a while and; b) being able to find neutral in traffic with a hot engine (good luck with that! ).

At any time, I can swap back in the original Ducati part and cable, and I am back to standard. But having used bevels for a long time, I won't be doing that and I won't be selling it/them either. It's going to get a straight cut primary drive conversion soon, too.

 

[Noobie]

It's always good to see alternate modifications and variables to keep the older bikes running. Enjoying the thread chap

 

[Vacant Possession]

Thanks! Now the sun's out, I just want to ride it!

 

[Robarano]

Cool thread. I hadn't seen it before.

 

[Vacant Possession]

Progress Update on the SS...
Bearing in mind I am intending to take the SS to the Red Kite Rally in Hay On Wye in Wales in late September, I thought I had better get a move on. It's only 175 miles each way, but I think that's a lot for the old girl and I want to be ready such that the bike goes there & back with no mishaps. The SS hasn't been started for about a year, cause in itself for a good worry. I have even forgotten where I have put stuff, so re-commissioning might be challenging.

Wheels
Whilst I love my Campagnolo's & Speedline's (less so the FPS's), a good friend asked me if it was really a good idea to be using 42 year old magnesium alloys designed for track days as everyday users. He had a point. So I spent the past couple of years putting together all of the parts for a set of valanced rim wire wheels; I have gone for WM3 2.15 at the front & WM4 2.5 at the rear, this is the same as the mag alloys. Although my first bevel was a 1976 borrani wire wheel twin disk 860 GT, I have spent most of my time on bevels with alloys and I know & like the handling with these rim sizes. I already have a set of wire wheels, but these are a) unvalanced and; b) have a WM5 rear rim which I don't think helps; this set are currently on the GTS, for the same reason of safety.

They have gone off to Steve@WheelWise for assembly. he seems to be a top man. Unfortunately not being a meticulous blogger, I didn't take pictures of the parts before send-off, but will post pickies of the wheels once complete.

Dash
I am not sure why it has taken me so long to getting around to putting the dash together; when I started wiring it in I had already done most of the hard work in building the sub loom to mate with the main loom and had built up the terminal block including support for power take offs for the new GPS speedometer & electronic tachometer; I had also already wired in the flying lead for the tachometer signal from one of the coils.

Mating the new sub loom with the dash only took an hour or two; I have honoured the wire colour codes on the new loom so any future owners will be able to follow my loom as it's essentially the same. I still have the original dash, loom, instuments & instrument drives should I want to revert to a shoddier set.
Working on the dash on my desk:

Here is the dash & sub-loom connected up, showing its underwear:

Here is the dash mounted on the bike, mostly wired in:

The underside of the dash whilst mounted on the SS:

and finally the dash running, without the instruments:

Relay
The original dash has an ignition switch in working but poor condition, so I wired in a 70A relay under the tank and used the spare fuse position in the fusebox to give me a relay switched fused circuit to feed the hungry ignition circuit - well, just about everything but the relay is switched by the ignition circuit.

In retrospect, placing the relay on the tank was a particulalry uninspiring decision (a rather nice euphemism for dim, dim, dim), as someone who fervently believes in RAS (Relaibility, Avaiability, Serviceability,) I have moved it to under the seat above the battery, which has worked well. It is at least accessible now in case of failure.

GPS sensor?
Yes, exactly. Where is it? I have absolutely no idea; it looks like I will have to buy another, whereupon the as now nowhere-to-be-seen GPS sensor will suddenly become apparent. I wasn't expecting dementia so soon .

Primary Drive
The GTS has a Nova Racing straight cut primary drive, I haven't done the SS yet because I wanted to keep it standard, but it is one of the main flaws in the bevel engine. However, like all the other changes I have made, the bike can be reverted to standard so this niggling fear I have is going to be addressed. I know exactly how much it costs to rebuild a bevel engine after a failure because I have done a few; if I can avoid this or even prolong the healthy life of my bevels, I will.

Notice the expanded capacity oil pump just visible - this pump is in both the SS & GTS, along with the invisible full flow oil filtering & three magnet particle pickup/extractors, one on the dipstick, one in the oil pickup tube and one under the oil filter. I run the bevels on fully synthetic oil.

More to follow...

 

[Noobie]

Every now and again, this pops up and it's refreshing to see the love and attention to a project along with as much description as possible. The build threads in the forum are always great to follow. Not long now before the Red Kite Rally

 

[Vacant Possession]

Thanks! I can't wait!

I will be completely excited when I finally turn out of the drive ; along with the most comprehensive tool set .

 

[Vacant Possession]

Two Red Kites
have gone since I last posted, so here is my update of my trials & tribulations covering mechanical stuff.

Here is a picture of the bike after rotting in the garage over last winter:

Note the two into one Conti exhaust system. It's wearing this because it fits really well and crucially Conti ship their systems with exhaust nuts which are 52mm. I am sorry to report that if you buy new pattern nuts, they are likely to be as small as 51.25mm and it does make a difference. They come loose, rattle, destroy the exhaust threads and pull out. Yes, it has happened to me. I have tried several including much vaunted German items from Ducati Kaemna and they were out of spec.

This year I wanted to run the SS with its original Conti's, and I found these nuts at Ducati Vintage, took a chance and they are 52mm. They don't come drilled for securing with wire, so I drilled them myself. They have to be drilled at an angle to come out in the right place, around 20-25 degrees. Securing the nuts doesn't mean the bike has been raced - it hasn't; it just makes good sense and avoids an engine drop, head removal & strip down and trip to a very good engineering works to either weld & re-cut or drill & weld in an insert (like Tony Brancato). Let's not, eh?

So here are the new nuts drilled, fitted & wired - they haven't come loose yet.

I also had a warped front disc, so bougth a new set:

I forgot I had to paint them! I had a bit of a panic as I only noticed on the day I was supposed to leave for Wales - but here they are fitted:

Don't worry - I did fit the bolts .

It's also running super expensive AMSOil, in the hope it will save me from a big end for a while .

I had one of these fail between Winchester & Newbury, which made gear changing interesting for 500 miles:

Which has given me the excuse I needed to remove the clutch cover & clutch, as I need to do that to access the detente spring, well that's my excuse anyway. so look what has arrived!

So finally after all this time, the old girl is going to get her straight cut gear set.

That's it for now, more on wiring & instruments on the way.

 

[Vacant Possession]

Instruments - and a bit of fun...
I have continued my journey building an alternative dash, to achieve a solid state dashboard with a GPS speedometer & electronic tachometer.

This is how the bike looks without dangly tachometer & speedometer cables:

It's finally lost the weep from the tacho drive .

The electronic ignition puts out a filthy signal, with voltage spikes way over 12V (approaching 200V!) which was 'interfering' with both the £30 eBay Chinese 85mm boat tachometer I have fitted, and also my nice Smith's unit. So it was time for a wee bit of electwonics. I wanted a pulse generator triggered by a cleaned signal from one of the ignition units/coils - as it's wasted spark, one coil output is like a normal twin.

I found the very promising Spyder signal conditioner - but hey! That's way too easy so I thought I'd build my own, to generate a 1.2ms pulse from a cleaned ignition unit signal.

Here is a circuit diagram for a falling edge triggered monostable timer based on the following (don't believe the R/C values):

implemented as Mk1 below:

It was missing any supply regulation/protection so I built Mk2, which has significanntly higher tolerance and has been potted for environmental protection - and as it sits under the tank that's a Very Good Thing. It also has an inductor & noise suppressing caps, but it is similar to the above with the addition of a simple supply regulation circuit.

...and in testing:

It worked really well on the bench, and (sort of) worked on the bike - which was an improvement over not working at all.

On the wales trip, it was still doing odd things with the tacho needle so I bit the bullet & bought the Spyder. When it arrived, connections are inside the unit so unfortunately I just had to have a look . Although it's £40, it's worth it. it is made woth modern micro electronics for which I simply don't have the tools or skill set - and it's properly potted. I don't know if it works yet, but I was able to dupicate my tacho signal generator harness so it was a straight drop in replacement. I'll let you know how it goes.

The Chinese instruments are a bit weird - I will replace them as you don't get a mileage/trip counter and you do get an 'hours usage' - not too useful on the SS. Also, if you use the parking lights, the speedo auto dims after a few seconds & the tacho stays lit . Weird, and they look like they come from the same supplier.

The upside is the GPS takes a couple of minutes to lock but otherwise is effective and quick to respond. It's got to be more accurate than the original Veglia etc.,

 

[Noobie]

Elektrikery is beyond me, I admire your patience chap

 

[Vacant Possession]

New Loom
I started having the fuse for the brake light & indicators blowing last year. I had a good look but the fault wasn't obvious - and I really wanted access to the connectors under the tank. Which means fairing & tank removal, not something I want to do every day.

In addition and as usual, in my haste to get ready for something I have now forgotten, I had done a poor job of integrating the Compufire series regulator into the SS loom. So this was an opportunity to clear that up. I had some aims - to improve the wiring *and* keep it simple and understandable - and of course be a neat, safe job.

So I bit the bullet and bought a new loom. Actually I bought two, one from Ducati Kaemna, which is expensive but comes with all the connectors pre-fitted, but they couldn't deliver; so I bought one from Mdina Italia. Just a word of warning, if you have an SS with the Suzuki switchgear, you'll be wanting the MHR loom. They seem to have got a bit mixed up with late SS's, and you are likely to get the wrong loom for CEV switchgear and different colour coded wires; you have been warned.

The Mdina loom is made by Old Racing Parts part #6X00030, identified as 'Cablaggio elettrico centrale 1983> Wiring loom 1983>'. Bearing in mind their reputation for making a lot of really useful good quality stuff helping to keep bevels on the road, I was hopeful.

No fault to Doug at Mdina, but the Old Racing Spare Parts loom was not a drop in replacement. I encountered the following faults:

• small csa wire used throughout
• incorrectly wired lighting circuit
• incorrectly wired ignition circuit
• inconsistent with original & misleading colour coding, especially on switched power.

Original Ducati looms use heavier duty wire and this loom is a real lightweight; I think there would be significant drops in the high current circuits.

This is not a drop in replacement - it's absolutely essential the loom is checked for errors against the circuit diagram before it goes anywhere near the bike.

Here are some examples, firstly what you get:

Ignition wire error:

Lighting wire error - they all needed unpicking & testing to see what the constructor had done, so as to reassemble correctly. I had to remove the crimps so as to keep the wires the same length (tedious!):

+ve leads in black!

Anyway, back to tidying up the regulator harness integration; this is the old loom, how it was:

Old loom again, you can see the enormous modern connector that comes with the regulator:

The mod was to use a 3 way spade connector, accepting a supply from the battery and the two alternator winding wires; I spliced in yellow wires to the regulator to de-mystify things in future. Looks a lot neater to me, and I can unplug the regulator from the loom. You can se the 70A ignition switched relay here too.

The bike already had a 70A relay switched supply, but there was a better way of doing it. My plan was to develop a sub loom so that it can be removed back to standard. The sub loom would:

• supply all fused circutis from the ignition switched 70A relay, direct from the battery
• make use of the spare fuse position to add a fused circuit solely for the ignition (spares fuses are in the seat!)
• use another fuse for the head/dip lights & ancillaries, i.e., continue a high current feed to the headstock where dip & head relays live
• power the tachometer signal conditioner from the headstock feed
• power the USB from the headstock feed.

Et voila! (Without the fuse box cover)

I made up a mounting plate for the head/dip relays which is attached to the headlamp bracket mounting, and spliced the relays into the standard headlamp sub-loom. The take-off for the USB sockets & tach signal filter are here too:

Another angle shows the GPS antenna mounting and a side look at the relay bracket.

Shock & horror, it all works a treat. I haven't bothered relay switching the horn - it's more of a squeak really.

I have to stop - I have run out of images I am allowed to include.

 

[Exige]

I have to stop - I have run out of images I am allowed to include.

10 per post I think, just start another post

 

[MHR91]

Good morning,
I was very interested in your article regarding the hydraulic conversion of the clutch.
as well as the other items, and this very, very beautiful restoration.
I am in the process of converting my 900 MHR bought new in 1981.
I would like to have your feedback since your conversion.
I opted for a Magura BUELL XB receiver (waiting for receipt) and would like to know the model of your master cylinder used.
Sincerely
MHR91
V Twin hydraulic clutch conversion

 

[Noobie]

@Vacant Possession