The inside of the engine looks not very good at all. Spark advance is broken and the primary gear is totally worn out. I am pretty sure more bad surprises will come, going deeper into the engine. I also noticed that the left engine cover has a 1971 production time stamp and the right side a 1968. I am pretty sure someone had the engine disassembled before me.
The engine is the so called “ashtray head”. The cylinder and head are designed for the US market. It replaced the earlier, classic Aermacchi cylinder/head. Customers in Europe didn’t like that design much and so it was available in Europe just for a short time period from 1969 to 1970 before they changed back to the classic knucklehead with the 1971 models. In US they kept the ashtray design until the arrival of the 1973 model of the Harley-Davidson Sprint.
Engine crankcase: L988
- 06/16/2013: First oil change at 120 miles (193 Km) – out HD 20W50 – in Castrol 20W50
- 06/19/2013: Re-Tightened nuts and bolts. Impressive how many became lose after that short period.
- 06/30/2013: The plan was to attend an oldtimer get together and market in Ansbach (mototechnia) which is about 35 miles from my home. I made 2/3 of the way, when suddenly the engine cut off (odometer: 160 miles). Luckily that was very close to Aermacchi parts distributor Rudolf Jungjohann. The error was found quickly: The circuit breaker screw came loose and was damaged, so I had no spark at all. We put a replacement screw in adjusted the timing and the bike did run again. Sadly there was no time left to attend the get together anymore on this day, but I did make it home on the bike without trouble (180 miles)
- 07/07/2013: Believe it or not – the kickstand broke into two parts just out of nothing. (odometer: 213 miles / 342 kilometers) Luckily this happened while in my own driveway and still sitting on the bike. Imagine what could have happened, while the bike resting on the kickstand!
- 07/08/2013: As I can’t ride the bike at the moment because of the broken kickstand, I decided to disassemble the right engine cover again to replace the oil seal for the clutch hub. Reason: I am losing tiny amounts of oil through the dry clutch. This happens because of my own stupidity, I mounted the oil seal with the wrong side facing the oil. I realized that by looking at pictures I did during assembling the engine.
- 07/08/2013: Replaced the tach drive because of a worn out oil seal. I had a NOS one at home already, because I expected that problem.
The GT once belonged to a fast rider. Those footpegs tell the whole story and it fits well into the picture together with the modifications made to this bike with a later and lighter seat, lighter tail light, missing fork dust-covers, cut-out clutch cover and other modifications – all with the goal of getting the bike as light as possible.
Because of the bad overall condition of the bike I assume the previous owner once lost interest in the bike and had it stored outside somewhere in a tiny Italian alley for decades.
Those footpegs will go directly into the trash bin. I have restored footpegs and reproduction rubbers in my inventory. The engine will get a good cleaning before disassembling and the airfilter will be replaced by a K&N replacement.
It is done, the bike is very handy now and easily fits into a large rack. The hardest part was getting the fork out of the frame. Heat and pure force did the trick. The weldseams look like having been done by an apprentice in his first year. Never seen such bad weldseams on my other Aermacchis.
The tires, rims and spokes will be replaced later. Hubs will be polished and reused. The oil in the front fork – or better what is left – is just mud, but there is hope that the fork may be repairable. The shocks are totally broken and can’t be reused.
So, here we are. I have started disassembling the bike. I have got this small original Ala d’Oro gas tank and seat as decoration in my garage. I couldn’t resist the idea of building a café racer and so I tried how those parts might look. However, I will restore it back to original condition, but ONE DAY I might build a café racer!
Oh yes, those silencers look pretty good. Just a little cleaning of the “Frankfurter Töpfe” and I can right use them again. 😉 Luckily I bought NOS replacements years ago and stored them safely in my basement.
The first step for getting the bike road legal again. I bought the bike without any papers in 2006 and as it was imported in very bad shape from spain it never had any german papers. The officials tested it 2 hours for beeing safe, beeing within noise regulations and so on. I also had them investigating the bike if it is in original condition as it was sold by factory in 1974. a car or bike older than 30 year ins original and very good condition can be registrated as “oldtimer” in Germany which brings some benefits and safes taxes for example.
I did some pictures of the finished bike. I am very proud. It almost looks like brand new with very tiny cut backs. On one picture you can see my special bike trailer which can be lowered to ground and lifted with an air compressor for easy loading by one person only. I just had to modify it a bit as it is designed for bike bikes with wide wheel base like my HD FXDL. The trailer also has pneumatic shock absortion and I love it. If you don’t use the trailer it can be folded and easily stored in the garage!
Video of first start after more than 6 years of restoration. The bike is already done. Not much to too anymore. Missing CEV169 and tach-drive.
High precision, fine german engineering for a special tool 😉 to open the inner clutch hub nut.
By the way as I have a 74 SS-350 this is the improved alloy clutch hub which was introduced on late 73 models. It can be identified by the higher number of toothes compared to the earlier steel hub. The late version also needs different clutch plates.
After some basic cleaning on the cylinder I noticed some bad scuffs in the bore which almost look like they are the result of rust. I somehow have the feeling that even a rebore and oversize piston wouldn’t compensate – maybe a 0.8mm – but looking for a better cylinder and oversize piston seems to be the right thing to do right now.
I am currently stuck on the engine, because I need to buy a 36mm wrench for the sprocket gear, borrow a clutch holding tool, and ordering a puller with longer arms to get the starter sprag off the shaft.
Today I packed the left side engine covers and the handlebar so I can send them out for polishing / rechroming tomorrow. I also have two ugly seat pans which I will bring out for sand blasting and powder coating the upcoming week. I will use the pan that comes out better.
A colleague lent me an extractor that worked getting the rotor lose. But somehow I am confused about the shaft, isn’t it supposed to have a notch and a key? Somehow this looks strange. I also learned the hard (hurting way) that it is better to leave the center nut loose on the main shaft when pulling the rotor.
As I am stuck on the left side of the engine as I need to buy or borrow a proper extractor to get the alternator rotor off I turned the engine and trying my luck on the right side. Removed clutch cover, circuit breaker cover, oilstick and speedo shaft.
Then again, I am stuck as I need a proper tool for removing the clutch.
After more than 2 years in which I didn’t have the time to work on my bikes, I have decided that I will continue with the SS-350. Well, actually I still do not have a lot of time left as there is still a lot of more important work to do, but I am going to take the time!
I took the carb, disassembled it and cleaned it with the ultra sonic bath and some “DREMEL polishing” and the result is not too bad. The carb was very dirty all over but not damaged as far as I can tell. I have already ordered a few new screws and new gaskets which are still available.
- Metering Pin: V10
- Low Speed Jet: 45
- Main Nozzle: 265T
- Starting Jet: 70
I collected parts that need to be replaced or were missing on my GT-350. The chain guard is in bad shape and will be replaced by this usable one after painting. The old style fork covers have been missing on my bike. They are not necessary but they were mounted by factory in 1970. Those mufflers are perfect NOS parts which costed me some money. I know, most people replace them by a single exhaust as a one-in-two exhaust just makes the bike heavier, but I like it as factory original as possible.