Å montere samt balansere nye spilehjul til moped og lett mc

 

Suzuki GT100 motorcycles history

By John Kjetil Lode

The blue bike is from a sales poster, and shows the GT100-A model. The second photo shows a Norwegian sold A model, that was sold from 1977-79. The last picture is one of my restoration projects – 4 bikes, all GT100 m models, in Indonesia, in 2008. I brought all of them to Norway.

2 MODELS

During the 1970's, Suzuki made 2 versions of the GT100. The oldest were given model «M» as a suffix, while the latter version carries the «A» suffix.

I read somewhere many years ago that Suzuki only built the GT100 models for a couple of years, I think 1973 and 1974.

Many of them were delivered in crates as CKV to be assembled in Indonesia. Indonesian customers purchased quite a lot of those bikes, and the others were shipped to other countries.

I know that some of them were sold in Malaysia, some in Thailand. 

Suzuki sold them obviously in Norway, and they were also sold in South America.

M model had loose, individual engine fastening brackets mounted with bolts to the front metal pipe on the frame, while on the A model those were a part of the frame, welded on.

The seats and seat locks were also slightly different, as was also the rear lower fastening bracket on the petrol tank.

The M tank, regardless of color, had a thin silver stripe with black center line, while the A model had a broader style tank decal.

THAILAND versions

However, I have 2 GT100 bikes in Thailand, and they are M models, but have the thicker stripe on the tank.

Thai models are a bit different from other models that were sold in Norway and Indonesia etc.

Thai versions basically came with only speedometer same as the A100, with A100 style controls and switches on the handle bar, front fork and wheel with drum brakes, front fender same as for the A100.

The rear light was also different, it was a square type, same as was mounted on the A100 at the time.

Let us continue with the typical differences between the M and the A model on the global market:

The head lamp with the fasteners were chromed on the M model, while the lamp housing and the brackets were painted black on the A model.

The M model had dark blue color in the speedo and the rpm meters, while the A models had a darker brownish – closer to black on the inside bottom of the meters.

In Norway, these bikes became very popular among the 16 years drivers. Models sold in Norway had a 6 volt generator, with contact points (contact breakers) and a condenser. The light coil on Norwegian models delivers 35 Watts, while on Asian models it was a 25W light coil. Also the head lamp on Norwegian models got a German reflector to cope with stricter rules for lighting.

Indonesian, as well as Thai market models came in some cases with CDI electrical system in stead of the more cumbersome contact breaker system.

Picture above shows the GT100 stator plate with contact points and condenser + coils

Rear fender: Suzuki GT100, presumably also the twin GT125 sold in Europe, has a longer rear fender then the Asian versions. It reaches a few cm further down in the rear end.

Tail lamp on Norwegian models was of a more luxurious style, borrowed from GT125 and GT185, while the Asian rear lamp was a simpler round glass, inherited from the A100 bikes.

ENGINE

The engine is a 2-stroke single cylinder version with a side mounted carburator, and a rotary disk to control the fuel/air intake cycle.

It has a 5 speed gear box, a separate two stroke oil tank and oil pump, so no need to pre-mix oil in the fuel.

In fact if you do NOT use the oil pump setup, the big end bearing on the connectiing rod will not receive proper lubrication.

(You CAN change this by swapping the oil guide plate on the left side of the crankshaft with a washer that has the same thickness.See photo below)

The cylinder block is made from aluminium, while the bore itself is hard chrome. This gives the engine the quality for harder revving, but if the piston seizes, it is not possible to rebore it, as it has no sleeve.

I found steel sleeves in Malaysia, so there are possibilities to get around this problem if your cylinder is already destroyed, but those cylinder liners are hard to come by, and the work is also for specialist only.

Cylinder sleeve made to fit into a GT100 cylinder block

I had a Suzuki GP100 standard piston, so the mechanic used it to get the correct bore

Here you can see the cylinder sleeve is pressed into the GT100 block

Maximum output on a GT100 engine is 12 hp (9.0 kW) at 8000 rpm; Maximum torque is 10.8 N-m at 7500 rpm

Capacity of the cylinder is 97 cc. The engine is based on the former HUSTLER 90. It is also very similar to the TS100 older engines, except that the exhaust port orientation is opposite from the GT.

In Norway, there were restrictions on light weight motorbikes. 

Max cylinder capacity less than 100 cc, 7 horsepower and a top speed of 80 km/hour. 

The Norwegian importer had to press in a restriction that greatly restricted the diameter of the intake. Most Norwegian users removed this restriction asap. 

The rotary disk was probably also a restricted version, but I have no evidence of that.

PROBLEMS:

I have a couple of testimonies during the years from people who worked as mechanics in Suzuki dealers workshop during the 1977-1980 period. One of them, a man from Haugesund in Norway, told me that he considered these bikes as garbage, and that they constantly had problems.

Also a professional dealer in Indonesia told me a similar story. He said the the bikes looked very good, but there were constantly issues with them.

I was the owner of a 1977 GT100 A model back in 1982-83. When I purchased the bike, it would not start, even if there was a spark in the plug. However, I just changed the plug, and it fired right up.

My bike had already been derestricted from a previous owner, so it was a great small racing machine. But it sometimes slipped out of gears. I guess previous drivers had been crazy in the gear change style. 

Also, the winker lamps, the brake light system and the head lamp were not working properly. I fixed all of the issues at the age of 15 what comes to the electric system, BUT:

The head lamp constantly blew up, and buying a new 6v 35/35W light bulb on the local petrol station was extremely costly. I ended up installing a 24v truck halogen bulb, and that one lasted, ha ha.

By the way, this issue with too high voltage or watt delivery to the front lamp is a common issue also with for example the Suzuki TS 100 ER.

Vibrations were another problem.

And the price for spare parts were just CRAZY.

COLLECTOR MODEL and accessibility of genuine spare parts

GT100 bikes are since many years coveted by collectors. Most of them probably rode such a motorcycle when they were younger. Also, many have kept their old bike in a garage, a barn etc.

Now they are proud of their little Japanese vehicle. But due to a very harsh climate in Norway, and since many of these bikes were the only vehicle the owner had to use, it could even be used on salted winter roads, and thus rust would be a huge problem.

So getting new rims and spokes would probably be ideal for many of those.

Then the exhaust muffler, and obviously the mudguards.

                           An unused genuine cylinder block that I sourced in South East Asia.

An item that is often missing on these machines, is the engine sprocket cover, and sometimes the large flywheel cover has damages due to the drive chain slamming into it due to neglect of chain adjusting etc.

The flywheel covers are often damaged, and the front sprocket cover is often missing on the old GT100 bikes

Now there are people who want to get their bike ready for some action on the road, and they also want it to work and look better after years of collectin dust and rust.

To those people, I can give some ideas about what parts you can use, if you can not find the genuine part, or if you don't want to spend a fortune to get those parts.

Fenders/mudguards:

I took this photo in Lofoten back in 2006. The bike on the picture has a Suzuki GP100 front mudguard installed.

You can of course to find a nice original one as time goes by, but at least this solution can lift the looks of your bike to a nice level.

In Indonesia, I found a total of 4 GT100 that were basically trash, and missing a lot of parts. If you study the above photo, you can see what I did, to at least make them road worthy.

3 of the 4 bikes were fitted with exhaust muffler made for Suzuki GP100. Quite easy job to modify it, and voila! You bike looks much better than with an old, rusty one full of dents.

I even put GP100 rear fenders on some of them, a Honda seat on one, Honda luggage racks and Yamaha RX tail lamps.

Speedometer and Tachometer were not available, so I just put on some custom universal instruments.

Over:

I bought a wreck of a GT100, put on new wheels (using TRS front hub and A100 rear hub). The muffler is made for GP100, but using an angle grinder makes it easy to install to the GT100 cylinder. The bike on this photo has also installed a GP100 rear fender (which is only half metal, but we welded it to the original ugly remaing part of the old one. You could of course also use the GP plastic fender that forms the front half of the mudguard.

Shock absorbers on this bike are made for Yamaha RX 135.

Now, some serious collectors seeing this might mock me, and yes, they already did. But I don't really care.

Some of them are religiously focused on getting everything original, no matter the cost. The funny thing is that back in the day, it was almost impossible to find a non modified GT100...

And yes, if you have plenty of cash and a supportive partner that think it is OK to spend large sums on this hobby, go for it!

The problem is that some of these parts are virtually impossible to source.

If you want to USE your beloved GT100, why not be practical about it, and take your time to try and find those missing items while you can still be happy about your project?

After having produced 2 models of the GT100, Suzuki started to sell the follow up model, the Suzuki GP100, already in 1976 in Asian markets.

The first GP100 models were not too different in the looks, compared to the GT.
GP100 & GP125 are basically the same bikes.
They turned out to be a better product than the GT100 when it comes to reliability, and they were actually produced and sold well into the new millenium in parts of the world.

Back in 1984-85 I bought a black GP100 from the community of Hommersåk, Sandnes kommune.
However, the seller lied to me, as there were so much money involved in getting the bike registered due to lack of paying the yearly road taxes, so I took an old GT100 frame with good documents, and build all parts over to that GT100 frame.

The seat was not plug and play, but I made it. 

Also the engine brackets on the GT did not fit with the GP engine block, so i got them welded, and i finally was able to register the bike.

It is a bit funny to discuss with GT enthusiasts concerning the 2 models, pros and cons. We do agree that the GT100 is a better looking bike, but I know that the GP100 is better quality wise, and you can fit a 125cc cylinder on the GP100.

But looks and memories from back in the days is a strong driver for many who are interested in a certain model, if it was dependable or not.