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Rebuild a 250 Alpina 1974 type 115

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  • Author

I change the front sprocket, the original one were probably smaller  ....

As I have a new rear sprocket in spare  (not yet installed) I will buy a new chain and have a complet new set. The idea to keep the original rear sprocket and chain was to reduce my expenses 😏...  

  • 2 weeks later...
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  • Finally, from (without registration):  To : New  seat New OKO carburator New tires Tank restored  with new petcock New chain and sprockets Bottom engin rebuilt

  • I use a socket with the OD machined down to fit onto that nut. Yes a clutch holding tool is required the way you are doing the work, but if you are going to pull a Bultaco motor apart again, cons

  • Engine is out 🙂, I wish to open it asap but the frame is the priority...  

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  • Author

 

I am working in the left side, needs the carburetor and clutch cable (next job in the schedule 😊).

I have a lot to do in the right side: tightening and adjusting the clutch, exhaust to install with custom parts. 

The next main goal is to fire the engine and do few feet's  ( ☺️) to checks the gears. After I will install the  12 volts  electrical circuit ...

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  • 1 month later...
  • Author

Left side is done, the air filter will be change after the first running tests.

Now time to adjust the clutch, in my procedure I need the kick start and set properly the clutch screws to get the plates parallel... locking with wire and closing the cover. 

 

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  • 3 months later...
  • Author

First firing today 😀, I did few runs in my street to check the gears.

So glad to succeed this step, the lighting coil reading is 14 volts as loading a battery (new electronic ignition).

I have some issues, probably the carburetor setting, but I will find the new motivation to finish this bike.

 

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  • 2 weeks later...
  • Author

Today new jets for the carburetor, air filter, lights  connected for tests. Without battery you need to proceed the electrical tests when running 😉....

Great progress, engin is now running without choke, restart easily, final adjustment will be done with the final exhaust. Tail light has some minor issues as loose contacts, ... 

Time to complete the electrical harness with switches, Side covers, handle grips before installing the gas tank and seat. Removing the zip - ties used for the tests. 

Next important target will be the pictures and files to apply for a Vermont registration. 

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  • 1 month later...
  • Author

I ordered this morning the side panels from In Motion, I have the items to complete the electrical circuit (Thinking to replace the tail light by an off-road one)... 

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  • Author

Electrical circuit done (using my Honda 12 volts battery for tests)...

Rear brake switch done, handlebar switches: Ebay for british bikes.

EMGO Horn/Dip Miller 157Hv/Wire 46-68736 

 

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  • Author

Today, waiting the side cover and missing the fuel lines and gas cap....

I already did some short running tests with a small gas tank. Soon on the road 😏

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  • Author

Waooh 🤣, first real run today with little dirt 🙂: This bike is amazing 😋...

Of course all is not perfect: gas tank went to close to the exhaust 🤥, idling is not clean 😒, front brake needs some adjustments 😌. Nothing very difficult .

We are far from the Japanese bike, good boots and the gears are going well 😏. Waiting my side covers and I will send my application for the registration... 2 years after the first post 😬.

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  • Author

Funny, don't forget to fill the gas tank for the carburetor adjustment 😝. During the first tests,  the idling was not stable, I refilled the fuel and have now a much better situation. Starting cold or starting hot is easy 😏. Brakes are working now 🥶...

I installed shorter rear shocks (320 mm now were 340), I am short and starting is easier, look is better for me (more trial style). 

 

Did the light come with the bike when you bought it or did you buy them after? If so where did you get the light kit from? 

  • Author

I bought a kit ignition and 12dc supply for the Bultaco: https://www.electrexworld.co.uk/acatalog/STK-154L.html

I did the electrical harness myself. Easy, I always have lights, the head light came from Ebay... I have no battery which is not with US request for street legal bike (some state have no inspection for Motorcycle). This bike will never spend a long road in the street...

 

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