Another 900 GTS story. The Black Pig

[Glawster]

At the risk of boring everyone I’m starting a new thread to chronicle either the demise or resurrection of “The Black Pig”, a 1978 900GTS I recently bought – quite unwisely. (Bike names in our house are down to my wife and this moniker fits). I had a 900 GTS in 1978 aged 20 and I loved it, so why not have another go?

I’ve read through both of VP’s excellent restoration threads and just managed to work my way through MartinW’s terrific story of life inside Eelco’s Darmah engine. I’ve picked up some good tips along the way and many trade contacts I’m certainly going to need. I have made some posts on other threads, but just to recap – this is the current situation.

The Black Pig.

Spare Engine & bits

Superficially it looks scruffy but straight. Frame and forks OK, Wheels original, Konis, tank has a tiny ding but otherwise looks good. Seat needs recovering but is sound. So I bought it…
What was obviously on show that I should have noticed:
o Where the alloy looks reasonable it has been sprayed with silver paint.
o The exhaust flanges are mangled
o The levers and master cylinder are unusable.
o The engine in the bike is number 850129 which I’m guessing is from an early non E/S GT. It should be 854376 and I do also have this engine, which appears to have been stored without oil for the last 30 years.
o The ignition switch has been bypassed with manual switch. I now know that parts for bevel twins are eye wateringly expensive, but you can get an ignition switch for about 30 quid new! Instead the wiring was hacked into.
o Every part of the bike is shouting “Botched”, but I knew better.
The BP’s had 5 previous owners, but the last owner’s had it since 1984. Last tax disc showed 2000. He assured me it has recently been running, but I couldn’t get it to start. In short it’s a motorcycle at a crossroads. Either it’s going to be rebuilt as an original GTS….or it’s broken for parts. I thought the best plan is to strip both engines and see what the cost of rebuilding will be. I can guess the cost of the chassis, but I won’t commit to any other refurbishing until we see how the engine looks.

My previous experience of refurbishing is limited to a cosmetic rebuild of a 1972 250 mk3. The engine runs well so I just cleaned it up, but everything else was covered. It was an easy job, completed in a couple of months and I enjoyed it. The result is Bella and she’s a little beauty!

I’m not an engineer and I don’t have access to engineering facilities (yet), but my neighbour Pat has a 450 mk3, a 350 race bike and an 851. He’s also a bicycle development engineer. He’s my mentor on this project and his first remark was – “Why are you trying to start it? Look at the state of it outside. Better to see what it’s like inside.”

I’ve started taking it down and have some questions already which I’ll post later.

If the select group of contributors from the other refurb threads are prepared to offer advice and comments on this project I’ll be very happy.

Derek

 

[Glawster]

I’ve started preparation for taking the engine out. I figured that since I don’t have a cradle to mount it in I’d be better taking off as much as possible while it’s in the frame. A friend in the VMCC has an MHR and he thinks he has a number of special tools. I’ll be picking these up asap.

In the meantime I have the following observations and questions.:

o I have the exhaust flange tool as it’s the same as for the 250. Unfortunately there was little for it to grip to so I drifted the back cylinder flange around by about ¼ turn. Then a big split in the flange came around and I decided I was probably doing more harm than good. So I cut off the pipes about 10cm from the heads and I’ll have to think about how to get them out when the heads are off.
o I thought I’d look inside the headlamp. Happy to see that there’s not much electrical stuff in their. Less happy that it was held on by a chipboard screw.
o Carbs off and ready for ultrasonic cleaning.
o Alternator off and the spare (original engine) alternator removed for comparison. The alternator on the bike is much wider and has 2 wires. Actually it is connected to the rectifier with household 2 core and earth flex….but only the live and neutral are used!
o The spare alternator is much slimmer and has 3 wires. I’ve read that they changed the alternator from 150 to 200w…but the one on the later engine looks a bit puny. Any comments on this?
o The rectifier / regulator actually only has 4 available positions so I’m guessing it’s the correct one for the 2 wire alternator?

It looks like this…

And these are the 2 Alternators

Amongst the parts I’ll certainly be needing, that I don’t see from the usual suppliers are…
o The plastic plug that the alternator wire comes through.
o GTS original handlebars – or some idea of width and rise. Anyway something similar.
o Front Brake Master Cylinder / Front Brake Lever / Clutch Lever.
o The dash with the little warning lights.
o I haven’t had the front wheel out, but the speedo drive looks finished.
o Probably a complete wiring loom.

And on the other side I have 2 Alternator covers, both of which look OK, so one can be sold.

 

[Derek]

o The spare alternator is much slimmer and has 3 wires. I’ve read that they changed the alternator from 150 to 200w…but the one on the later engine looks a bit puny. Any comments on this?
o The rectifier / regulator actually only has 4 available positions so I’m guessing it’s the correct one for the 2 wire alternator?

I have wiring diagrams for both the 860GT and the 860 GTS, both show 2 wire alternators, I'm sure the 900GTS would have also. I believe it is a known mod to fit the alternator from a 916 for an increased output.

 

[Vacant Possession]

Excellent to see you posting and I wish you the best whatever your choice.

The larger alternator/stator winding is what I'd expect for an 860, two wires only. The smaller set looks distinctly 750 ish; But that is walking off the edge of my knowledge.

Parts are available on eBay but I suggest you take your time, I have had some blazing deals, some which have been totally pants and some which I have let go.

Replacing the bearings in the entire engine isn't so bad but the mains are a bit pricey. If you need to do the bottom end, you'll be looking at 'quite a lot'; Many of us with bevels have form here and I'd like to recommend Godden Engineering both for their quality of service and communication.

 

[MartinW]

YMP sounds a lot like MMT!
“Why are you trying to start it? Look at the state of it outside. Better to see what it’s like inside.”
Just what he would have said.
Good luck and don't get stuck. I have never known a more friendly and helpful bunch than on this site.

 

[Vacant Possession]

Speak for yourself

 

[MartinW]

I obviously need to get out more...

 

[NeilD]

looking forward to following your progress.. and hoping for some inspiration to do something with my Darmah!

 

[Glawster]

Good. I'm glad I have the attention of the Usual Suspects. Just needs Ducati Paddy to log in and I think there's enough sensible opinion to cover everything!

VP - Thanks for the Godden contact - although I suspect that if the bottom end's gone that might be the tipping point.

Martin - Yes, MMP could prove to be a good un. Time will tell.

Yes, I guess the bigger alternator is the correct one. Just needs re-soldering.

Now, briefly the good news:
- Simon, who I recently met through the VMCC has an MHR which he bought a couple of years ago along with a little tool chest full of treasures. Amongst them were the following tools, most of which I have haven't yet found the application for, but for sure they will be very helpful. Anyway I grabbed the lot and was very grateful. Simon is a fellow Tyke, exiled in Gloucestershire and a damned fine fellow!

The other positive is that I have a local independent bike workshop owned by Ducati factory trained technician Tim Hyett. Tim's experience is mainly on modern stuff but he has rebuild many bevel twins. He's happy to be presented with a box of clean parts for assembly if required. This could be my best option for peace of mind that it's put back together correctly.

On the more negative side, I've just taken off and stripped the front cylinder head. I'll get Pat to have a look at the valves and head but I think there's some work required there. The main problem though is the exhaust flanges. I've soaked this one in WD40 but I can't get it to budge. Any advice on this appreciated.

Also, to extend the carpentry theme, after finding the headlamp rim was fixed with a chipboard screw, I found that the retaining clips for the lamp are actually bent 4 inch nails....
Maybe I'll find a couple of wooden pistons?

Ah well, rear cylinder head next!

[/LIST]

 

[Glawster]

Good. I'm glad I have the attention of the Usual Suspects. Just needs Ducati Paddy to log in and I think there's enough sensible opinion to cover everything!

VP - Thanks for the Godden contact - although I suspect that if the bottom end's gone that might be the tipping point.

Martin - Yes, MMP could prove to be a good un. Time will tell.

Yes, I guess the bigger alternator is the correct one. Just needs re-soldering.

Now, briefly the good news:
- Simon, who I recently met through the VMCC has an MHR which he bought a couple of years ago along with a little tool chest full of treasures. Amongst them were the following tools, most of which I have haven't yet found the application for, but for sure they will be very helpful. Anyway I grabbed the lot and was very grateful. Simon is a fellow Tyke, exiled in Gloucestershire and a damned fine fellow!

The other positive is that I have a local independent bike workshop owned by Ducati factory trained technician Tim Hyett. Tim's experience is mainly on modern stuff but he has rebuild many bevel twins. He's happy to be presented with a box of clean parts for assembly if required. This could be my best option for peace of mind that it's put back together correctly.

On the more negative side, I've just taken off and stripped the front cylinder head. I'll get Pat to have a look at the valves and head but I think there's some work required there. The main problem though is the exhaust flanges. I've soaked this one in WD40 but I can't get it to budge. Any advice on this appreciated.

Also, to extend the carpentry theme, after finding the headlamp rim was fixed with a chipboard screw, I found that the retaining clips for the lamp are actually bent 4 inch nails....
Maybe I'll find a couple of wooden pistons?

Ah well, rear cylinder head next!

[/LIST]

 

[NeilD]

mine had wooden spacers between the frame and inner mudguard must be a Ducati thing!!


2013-03-16 014 by GUZZINEIL, on Flickr

 

[Vacant Possession]

You'll find an exhaust spanner very handy - I have the cheapo edition but you can get a better one too.

My exhaust clamps were similarly tightly in and my cheapo tool wasn't up to the job; I left that one for Jan Biggelaar, perhaps the more beefy one might have done the trick.

 

[NeilD]

a bit of heat on the exhaust flange might help?

 

[MartinW]

I recognize some of the tools, especially the thing for taking extracting rocker shafts and holding valves down whilst shims go in, neither of which I had!

 

[cp14bob]

Headlight retaining clips

BQ or ! used to hold glass in Alloy Greenhouses

 

[Glawster]

VP - Yes I have the "deluxe" exhaust flange spanner (came with my 250), but these flanges are way beyond any hand tools. Pat's gone away to think about it so I'm hoping he comes up with a solution.

We also had a hell of a job to get the front cylinder off. It would move about an inch then was binding on one of the studs. Hours of WD40 and 3 in 1 later - and I'm ashamed to say 2 broken fins - it finally gave way. Must remember to slap some copper slip on the studs on re-assembly. I'm hoping the back pot might not be so bad, on account of it being out of the firing line of spray from the front wheel

Anyway Pat looked over the valves, seats, cams, rockers, piston and barrel and thinks they are all quite seviceable. Maybe I can get away with new rings? Barrel seems to be 86mm measured on my chinese plastic Vernier gauge (£6.49 post free ex Ebay)

Bob - Good point on the greenhouse glass clips. I reckon they might do the job! Headlight unit is Koito which seems to be Japanese, but it does fit after a fashion so I think that will be staying.

Neil - your problem there is clearly unseasoned timber. you must replace with seasoned hardwood or tanalised softwood at the very least...

 

[MartinW]

Have you tried freezing spray on the exhaust ring after heating the head, maybe in an oven? That and a bit of repeated impact might work? You haven't much to lose as you'll probably have to re-thread them anyway if they are badly corroded. It's a fine thread and a big area

 

[Glawster]

Bob,
Excellent tip. Just robbed my greenhouse of a few glass retaining clips which fit perfectly! Hope there's no gales coming.

 

[Glawster]

Just unpacked my new bench grinder / polisher. I needed to believe this ugly heap could be turned into something beautiful. 5 mins on a bevel cover produces a nice effect.
Memo to self:- Don't use polisher in the garage. Everything's covered in fibres and fly.

Next problem is to remove the left footrest bolt. The head is too big to get a socket round it and has a slot cut in it. I've got a car wheelbrace which has a flat end that fits, but can't seem to shift it. A bit more WD40 perhaps.

 

[Glawster]

Pat's just been round with his patented Ducati footrest removal tool. Putting a long lever on it still didn't shift the bolt, but mounting it in an impact driver shocked it loose. I don't think this impact driver has been pressed into service since those 1970s soft crosshead screws that held together Jap bikes went out of fashion. Nice one Pat and my turn for the beers at the VMCC pub meet tonight!

Sadly my lovely GT1000 departed today. I need the space (and funds) if this project will come to fruition. Is there a better motorcycle engine than the DS1000? For me it has enough of everything. Maybe I can find a cheap Monster or Multistrata and still have enough cash for the GTS.

 

[DrD]

P Is there a better motorcycle engine than the DS1000?

I had use of a MS1000DS for August and impressed with the motor too, compared to my 1993 900 it is smother but low rpm torque seems a bit down on the 900 carb motor.

 

[Vacant Possession]

That looked like a nasty job! Mine used Allen screws so for that particular job there was no problem.

Like the GT! I agree with you about the engine, Richard @ CMW loaned me an 1100 Monster with a similar generation engine and it was quite simply the most fun bike I'd ridden for a long time; The only problem in my eyes was the pathetic petrol tank or I'd have bought one.

 

[Glawster]

Yes, the other side had the correct Allen head bolt and was no problem.

Now - I've just taken off the wiring loom and all associated bits. It's an ugly mess with various additions and poor repairs.
I'd like a new loom but I nearly fainted when I saw the price of Mdina at ca £250 (I hate it when they don't put on the VAT). And that's listed as a 900SS loom, so presumably it doesn't have the wiring for electric start. I notice that Mdina also lists various loom connectors.

My question is - has anyone made up their own wiring loom, or have a recommendation of either a bespoke loom made to order...or someone who sells all the bits?

I bought a loom for the 250 from Barry at Classic Ducati. It was a first class job and cost £90. I struggle to see how a loom for a twin should be £250. Or is it my Yorkshire genes taking over?

 

[Vacant Possession]

Yes, I have made up my own loom and it worked very well.

I have ended up reinstalling the original simply because it is the original; It did require some patching.

I bought a loom from a Paso being broken to get hold of the correct wires, and with some good tools for pin extraction and pins/connectors from Andrew@Mdina it isn't too tricky. You'll need the green SS-33 (id=3.1, od=3.6)& yellow SS-34 (id=2.7, od=3.2), BTW.

I can also send you pickies of bits of my loom where yours has been 'improved'.

Doing that will be a lot cheaper too and will match the bike.

 

[Glawster]

Thanks VP. I'll give the wiring some thought. Actually the price from Mdina is £205, but it still sound a lot. Anyway, that's some time in the future.

Regarding the clutch pushrod bits, I just removed mine - and this is what came out (clutch at the LHS). Doesn't look anything like what's in the parts manual! Length is 242mm.

Clutch springs are OK for length and plates total thickness is 39.4mm so I think they should be OK.

 

[MartinW]

clutch pushrods

If that is the same as the Darmah then you are missing a couple of 5/16 rollers and the bullet that pushes on the clutch arm. I'll get the list of my measurements out of the garage tomorrow. You can make up a dummy rod the exact same length to see if it works with your parts. I'll send you a couple of the correct rollers if I can find them, too.

 

[Glawster]

Thanks Martin,
The clutch lever did appear to be lifting the clutch so I'm not sure if I need any extra pieces. I'll find out on reassembling. Thanks for the offer though - I'll let you know if I need some rollers.
Best regards,
Derek

 

[cp14bob]

http://bevelrubber.com.au/cart/index.php?main_page=product_info&cPath=70&products_id=129

Aus picture of rods and positions for guidance

Just home from the masher to find a lovely pair of bevel pistons and rings

Thanks Paul

 

[Glawster]

A bit more progress to report. It honestly is two steps forward and at least one back…
The front cylinder was a hell of a job to free off. It eventually gave way, but not without me breaking 2 fins as previously reported. Pat saved the day by welding them back on and I reckon after they’ve been vapour blasted the repair won’t be noticeable. First class job.

The mangled exhaust flanges were another matter altogether. I waited for my wife to go out and put them in a hot oven, then jammed a piece of fabric filled with ice cubes down the cut off exhaust pipes, but they were still stuck fast. At this point my luck changed when I met with Andy (Pat’s Dad). Now Andy (who I’m guessing is in his late 60s) is an ex racer and I was invited to view the inside of his garden shed. Well I call it a shed, but it's a proper workshop - it’s about 20 x 12’ and stuffed with lathes, milling machines, pillar drills and all kinds of other stuff I don’t understand. What I could appreciate better is his collection of race bikes:
o Matchless Metisse G50
o Triumph Metisse (he likes his Rickman frames)
o Another Triumph twin – I think in a regular frame.
He also has a T100 he uses for pottering about on with his wife Jenny on the back.
Anyway Andy is clearly in the Premier Division when it comes to sorting out bikes and he agreed to have a go at the exhaust flanges. I haven’t been back yet, but I understand he’s successfully removed them. I think he also fancies rebuilding the Ducati engine but he’s too polite to say so.
I took most of the bottom end bits off while the engine was in the frame – my engine jig comprising only of a B&D Workmate. The clutch basket was pretty easy to remove as only the lock washer was holding it on – it wasn’t even finger tight. Pat’s comment about not starting it once again proving to be prophetic..

Now, out with the engine and split the cases. Hmmmm. I should have looked harder at this botch on the centre lower 10mm engine bolt. The bike had a side stand and it was attached at this point (correctly) but not with a regular 10mm bolt and spacer, but with what appeared to be a threaded bolt with some kind of fine, non metric thread cut into it. I wrongly thought that this threaded stud would not stop the crankcases from parting, but actually there was also a nut buried down where it could not be removed.

I had to call Pat in again and the low tech solution was to part the crankcases as far as possible (maybe an 8mm gap), get a hacksaw blade inside and cut the offending stud through. It worked a treat! Here’s Pat furiously sawing a Ducati engine in half…

And here is the offending stud finally removed. At least it does have a 10mm thread where it was screwed into the crankcase, but the thread on the open end is a mystery. The bolt below is the correct bolt from the spare engine.

However, the good news is that Pat at least thinks that the big end, mains and gearbox are in very good condition with no wear apparent. So that seems to give the project the green light to go ahead and commit to the rebuild. I also want to dismantle the spare engine as well. I’d like to use the crankcases from this one if possible as it is the original engine.

 

[Glawster]

I managed finish the stripping of the "first" set of crankcases. Just managed to get them in the oven and all the bearings pretty well fell out. Unfortunately one of the Main bearings dismantled itself from it's cage, and while it was easily reassembled, it seems crazy to risk re-using it. Ker-ching...another £160 for new Mains!
On the "second" bottom end Pat and I couldn't manage to pull the crank pinion and flywheel off the crank. I suppose it's been sat for 30 years open to the atmosphere and is stuck fast. I took this set bottom end in to Cheltenham's finest Ducati specialist Tim Hyett who seems quite relaxed about freeing it off. He'll also take out those pesky blind bearings with his Ducati tool. I read Martin's interesting account of making a tool with a modified rawlbolt but I didn't have the energy.
I've also had to admit to myself that while I might have the enthusiasm, I don't possess the level of competence required to rebuild the engine correctly so I'm turning it over to Tim. A bit disappointing really, but at 55 I'm starting to understand my limits!
Andy's dad Pat certainly did a great job to remove the mangle exhaust flanges so that's a relief.
I sort of felt that I'd "crossed the Rubicon" yesterday when I called Nigel Lacey and ordered gaskets, oil seals, o rings etc...and today I got a quote for the main bearings, stainless bevel tubes, and other bits and pieces from Mdina.

I have to admit another mistake when I broke a piston ring. It's gutting because all the other rings are well within wear tolerance. It seems that standard 86mm rings are almost non existant and I'm waiting for my last hope Road and Race in Australia to confirm they have standard rings. Otherwise it's a rebore and new pistons...Kerching!

Tonight I thought I'd do a bit more dismantling on the rolling chassis.
On taking out the back wheel the hub looks a real mess - badly scored. Please note the lovely blue painted detailing adorning the rusty Raedelli rims...

And the shoes are similar...

I don't understand how it's possible to get a rear brake in such poor condition - it's hardly used!
Please post your suggestions on potential suppliers to re-line the shoes and skim the drum. I'm assuming (hoping) this can be done.

I had a good chat with Nigel Lacey (and his wife). I've met them before and they really are a charming couple. They also have a GTS which looks really nice in Black and Gold and they were telling me about a 3,000 mile tour of Spain and Portugal they took on the bike. Mind you I suppose Nigel could probably do a full rebuild by the side of the road if required!