The GT550 Lives !

For those who have been following along, the engine started up almost immediately and I took it out for a short ride today. It sounds good, no ‘bad’ engine noises at all after about 20 miles so I think I’ll call this one a success. There is still a lot of snow on the ground – I have about a 1 metre pile at the end of my driveway for example, but there is lots of snow elsewhere on the sides of the roadway and people’s yards as well, although the roadways are generally clear. The air is a bit brisk, but the real worry is all the sand and small gravel on the roads from the winter as they have not been swept yet, plus as the temperatures drop quickly in the evening things like sewer covers can get quite slick.

One minor problem I had during the first few miles was the turn signal switch which seized up solidly. It had been a bit tight when I was testing it, but I thought it would loosen up with a bit of use. After disassembling the mechanism, I found nothing wrong with it mechanically and so just lubed it up with some dielectric grease and it now work fine.  At any rate, the plan for the next while is to gradually put some mileage on both the GT550 and the GT750 project bike  over the next few weeks, and to see what else shakes loose, or needs to be adjusted before taking either bike for longer runs.  I also have a few additional photos etc. to go up on the GT550 web site, as well as a short list of minor updates so that will keep me busy also.

With a bit of luck, I may be able to show them off at the CVMG Bike Night sometime in the next few weeks - all we need is some warm weather !

GT550 Rebuild Continues

Following on from my previous post on my Suzuki GT550 rebuild, it seems that luck is in short supply as I am still waiting for a couple of seals to arrive.  For whatever reason, there seems to be an inordinate number of basic things just not available for this specific model – like an o-ring for the starter motor for example which Suzuki has rather unkindly discontinued ! I have one coming from an NOS parts supplier in Toronto, and while I likely could also have matched one up from an industrial parts catalogue if required, it all just adds time to the process.

While waiting for things to either be located, or if located for them to be shipped I have gone ahead and assembled most of the engine – while doing so, I noticed that in addition to revamping the clutch assembly Suzuki had also changed the gudgeon pin design. The piston failure in the centre cylinder seems to actually have started with the gudgeon pin cracking in half, and so I was pleased to see that the new pins had a much thicker wall, as can be seen in the photo to the right. Presumably then, the failure my engine had was not an isolated event !!

I realise I said this in my post of March 20th, but if everything goes according to plan, I may have the engine in the frame this coming week, possibly in time for April Fools Day !! 

GT550 Starter Clutch

The new style clutch basket and starter drive assembly has arrived for the 1974 GT550 I’m rebuilding, together with most of the seals, gaskets and other bits and pieces I need. I managed to track the starter clutch assembly down in the UK from Suzuki-Dave who is a member of the UK Kettle Club, and from whom I’ve bought other items previously. Tracking down all the other seals I needed has taken some time, as some have not been available from Suzuki for quite a while – for example the oil seal that goes behind the drive sprocket ( 09283-25050 ) I finally sourced from a dealer in New Zealand. Most of the crankshaft bearings and the connecting rods are no longer available from Suzuki either, so I’m hoping that the crankshaft I have will be OK. 

I spent a very pleasant day up at Fred’s earlier this week washing the engine cases in his parts washer, and they are now look much better. I also rinsed out the crankshaft assembly just to try and flush any remaining small bits of aluminium off the big end bearing etc., and that all looks pretty good as well. As my wife is out of town this week, I very seriously thought about washing the crankcase halves in our dishwasher – this has been done by a number of folks and supposedly works well, however my guess is that they are all single (or divorced) so in the end I decided that I’d better not push my luck with SWMBO’d.

As per Suzuki Service Bulletin #GT-26 of August 15, 1975, the new starter drive assembly ( 21200-34820 ) was introduced with engine number GT550-63692 and is quite different from the older style, as can be seen from the photo to the right – the new style is on the left side of the photo with the new starter clutch gear above it. These assemblies come as matched sets and per the bulletin must be replaced as a unit. Of course none of these parts are still available from Suzuki, so anyone restoring these engines will likely have to take their chances.

With a bit of luck, I should have the engine back in the frame by mid week,

The 1974 GT550

Some time ago, I picked up a 1974 GT550 which came to me with the engine stuck. As a part of the deal, I also was given two donor bikes of the same model, but different years. Basically, the bike was complete, and just looked too good to pass over even though the cost to repair was probably going to be more than its value. As I did with my GT750 project, I’ve started a web site to capture additional details as the repair work on this GT550 progresses.

As was often the case, the donor bikes had been left outside with the carbs and exhaust pipes removed, so water, snow and whatever was blowing by had made their way into the engine cylinders and they were solidly stuck and not looking very good at all – as per the photo to the left.  After letting the engines soak for several weeks with penetrating oil,  I pulled them apart to see what could be saved, Interestingly, both donor engines appear to have failed due to holed pistons, so naturally I was curious whether the project GT550 had the same problem. As well, I had been told that this model of Suzuki had a fragile starter, but when I pulled these apart both donor bikes showed no sign at all of problems. One of them even still had its starter motor fitted, and when I’d pulled it out, I tried it with a power source, and it spun freely.

At the end of the day, I had about one and a half engines with serviceable bits and pieces suitable as spares – one actually had a set of first over pistons which are quite rare to find now. The barrels were in rough shape, but at least could possibly be bored out, and one set of engine side covers were worth keeping    

The next step was to strip down the project bike and see what its problem was. As it turned out, it had more than one. Once the head was off I was initially relieved to not see any holes in the pistons, however the centre cylinder had a lot of small metal particles on the top of the piston as well as in the exhaust port, and once the barrels had been pulled off it was clear where they had come from per the photos below left and centre. The centre piston’s gudgeon pin had snapped, and then the piston had essentially self destructed. The bits falling down from the broken piston were lodged between the crank throws and the case which was why the engine wouldn’t turn over. As well, when I pulled off the clutch basket, the starter clutch assembly basically fall apart as the centre boss had come completely apart. In the photo below to the right, you can see the broken one to the left, and what it’s supposed to look like to the right.   

Suzuki completely redesigned the starter clutch assembly in 1975, the year after my bike was built and obviously the updated version had never been installed.  The service bulletin which details the changes and new part numbers is GT-26, dated August 15, 1975 and a copy can be found here. I have two ‘good’ old style starter clutch assemblies from the donor bikes as neither of them had been updated either,  but I wasn’t too happy with doing this as I could reasonably expect the same failure mode again at some point – and as I was putting this on the road for my wife, I doubt she would be impressed if it quit working !

I am looking to see whether I can track down a new style starter clutch assembly and we’ll see what happens. At the moment, I’m waiting on parts, seals and gaskets before I start to put the engine back together

Calgary Motorcycle Show

Well, the weekend has come and gone and I spent yesterday (Monday) just puttering around the house after four solid days at the Calgary Stampede Grounds in the Roundup Centre where the 2009  Calgary Motorcycle Show was held. This is a travelling  show that visits several cities at this time of year, providing a welcome break from the winter blahs, and while I haven’t seen the final attendance figures it was a very busy place in our corner of the building.

The local Rocky Mountain chapter of the Canadian Vintage Motorcycle Group (CVMG) had a large number of vehicles on display ranging from a 1935 BMW through to a 1983 Suzuki Gamma, and as Suzuki was featured this year, we had good selection of this make on hand. Front and centre on the RMS CVMG display was Wade’s immaculate and all original 1972 GT750 seen to the right. Also on display was Fred’s 1976 RE5 rotary together with a cutaway of the engine which we (mainly Janice actually) cranked over by hand for hours. It never failed to attract a lot of attention as you really need to see it operating to appreciate just how different an engine design it is, and many people are not aware this type of engine was actually ever used in a motorcycle. It was also very interesting to watch people’s faces as they walked around our display – clearly seeing these older bikes brought back a lot of memories for many people, and you constantly heard parents telling their kids about how they’d had one just like one of the ones on display. The other interesting thing was the number of folks who had been given their father’s or grandfather’s bike which had been sitting for the last who knows how many years in a garage or shed, and who now were looking for information and help to get them running again. Possibly a few of these will be on display next year !

Getting the bikes to the show for all of us was not a lot of fun on Thursday as it was -15 C and snowing, but everyone chipped in and helped each other to unload and push the bikes through the snow in the parking lot and into the Roundup Centre.  Fred set the record for most trips, but I think the one that came the furthest was the absolutely beautiful 1951 Vincent Black Shadow owned by a club member north of the city. Perhaps one of the biggest concerns (other than having an accident) was the amount of slop and road spray there was for those of us using open trailers – after the hours of shining and polishing, the last thing you want is slush, sand and salt spray all over your pride and joy ! Fortunately the cover I had worked well, and I had only a small amount of tidy-up to do once I’d unloaded.

My own contributions were my 1974 GT550, and my project bike with the burgundy tank seen to the left, and which a few of the members call a GTS750 as it is a GT/GS hybrid. For me personally, completing the project was the culmination of six months of very satisfying and rewarding work, and the perfect tonic as it took my mind completely away from cares, pressures and concerns of my former employment, and allowed me to fully disconnect and move into retirement mode.  All in all, it was a great experience, and I’m already looking forward to next year’s show.

Next on the agenda is to get the GT550 running and also do some work on my Yamaha YA6 along with the other usual household items – I suppose at some point I may consider looking for a part time job of some sort, but at the moment I’m not sure where I’d be able to find the time !

Suzuki GT Mirrors and Things

One of the (many) little challenges you run into with restoring old Suzuki motorbikes is the rear view mirrors. The ones that originally came with the bikes in the 1970’s had a Suzuki ‘S’ embossed on the mirror, but none of the after market replacements whether from Suzuki or a third party have this. Naturally, as a result, these original, and now quite old embossed mirrors are in demand and I was following an eBay auction that ended yesterday where the ‘winner’ paid $101 for what was otherwise a $10 mirror ! Actually, I just noticed a shop in Thailand asking $9.99 for a pair of mirrors, so you don’t have to pay much if you don’t want to.

Needless to say, the demand for these mirrors provides an incentive to preserve the ones people already own – and it is not uncommon for folks to install cheap mirrors for general around town riding, and save the embossed ones for shows and events.

I just picked up another bike (a 1974 SuzukGT550) which looks really nice but in addition to not running also came without mirrors. As I have a few embossed mirrors that would fit it but with broken mirror glass, I thought I’d spend a day and see if I could I could just repair a set that I had. The starting point is shown to the upper left – the key parts are the mirror disc, the rubber beading that holds the mirror in place, a paper spacer that goes in behind the mirror glass, and the old embossed mirror mount. I had to carefully bend the backing a bit to get its original shape back as the back had originally been hit and the mirror arm had been pushed inwards with enough force to break the original glass. After gently (and also not so gently !) massaging it for a while, I was ready to try and add the glass. To the right you see the mirror backing ready to accept the glass. The new mirror glass replacements I got by taking apart suitable third party mirrors which are readily available from many sources – standard mirror glass isn’t suitable, as the mirror is slightly convex to give a wider field of view of the traffic behind you. I found that at least for the ones I used, I could carefully pull the rubber edging at the point where it is seamed, and then mirror disc you need for the repair is easily released.

I used a heat gun to warm up the metal backing, and then basically pushed the mirror with the edging installed on the edge of the glass disc and very slightly lubricated with some dish detergent (the wider side of the rubber edging, as seen in the photo to the left, goes to the back of the glass disc), until the glass ‘popped’ into place, at which point I adjusted the fit with a jeweller’s fine screw driver so that everything was equally spaced around the edges. If anyone plans to try this themselves, be sure to wear good gloves and eye protection as the glass is easy to break, and gashing your hands on broken mirror glass will definitely put a dampener on your day !

The final result looks ‘OK’. You can obviously tell that the mirror is not new, and the dents and dings are still visible in the photo to the lower left, but I chose to think of these as adding character – heck the mirrors and the bike are both about 34 years old, and its not exactly a trailer queen, so I don’t mind it looking its age. You can see the glass side of the repaired mirror to the lower right.

Bottom line – fixing the one broken mirror gave me a matched set of rare and increasingly expensive embossed Suzuki mirrors for the newest addition to the garage, so I’m happy.

The ‘home’ site for my GT750 project is here.