Hi there, nice that i found this forum and i am not the only Bultaco addict round here...I just wanted to sell a 183 Sherpa i bought for a friend, who didn't want it anymore. When it was standing in my garage, i said to myself: he, thats a really nice bike...It was stored 25 years in a shed and had a real daily driver life before that...I put some air in the tires, brake cleaner in the carb, some fuel and the engine fired up. I could not believe when i made a few rounds with it on our place...and decided, thats my new project, the bike i always wanted to have since i was 18. crazy, and makes really no sense, cause i have three other Bultacos and a montesa trial...

I stripped last week the bike. new tires, wheel bearings, steering head...what is always necessary. but i like the look of the original alloy tank. old warrior or something...so decided, to keep the look, like it is. (with rusty kickstarter...) I liked the patina of the bike. ( ..ok the red pipe...) to be continued...

 

 

Edited December 14, 20178 yr by dr-alpina

Real nice bike !

 Best decision you could make so far, keep the bike as original as you can, just OEM parts, great look. The rusty spots will go away with the time and just some care.

 

Some things I would so:

 

1. Chain tension is too much, there should be a 1cm distance between the upper side of the chain where the chain tensioner sits and the underside of the swing arm.

2. You should mount an chain guard,

3. The rear fender, a used OEM Aluminium fender or white plastic fender would be great...

Bultacos should be red.  The blue ones just don't look right.

I think both mudguards should be red, not too sure if your rear one is original, can't remember the deep valance.

Has anyone found that the front mudguard clearance is very small (10mm.).?  It is worse if you use a 3.00 x 21 tyre instead of a 2.75 x 21.

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19 hours ago, stpauls said:

Bultacos should be red.  The blue ones just don't look right.

Bultacos should be blue with a white frame. The red ones just don't look as good...

..when i got the engine running, it sounded ok but some times you could hear the piston. After stripping and measuring it had around 0.25 clearance...!

I decided to put a new piston but found another old cylinder with this piston. clearance 0.10...after cleaning it really looked better , but have you ever seen this holes? looks homemade for me and whats the reason?  

The holes are so some lubricant can get on the port bridge & stop it from seizing, some bikes had this standard

Those holes are so the engine can get some extra lubricant on the hottest part of the barrel, the exhaust port side of the cylinder liner. I think all of the later Bultacos have them even the 125cc ones.

I have 5 pistons around and no one has that. Even the Alpina 213 or 199A...it is a Mahle Piston. selfmate or could you buy this? 

Some models don't have an exhaust port bridge so don't benefit from having holes there.

One of my Bultacos is an Alpina 138. It has no exhaust port bridge, but the only piston I could buy at the time I had it rebored (about y2000) had those holes.

On 12/16/2017 at 2:10 AM, scifi said:

I think both mudguards should be red, not too sure if your rear one is original, can't remember the deep valance.

Has anyone found that the front mudguard clearance is very small (10mm.).?  It is worse if you use a 3.00 x 21 tyre instead of a 2.75 x 21.

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The front trials tyres we buy now are taller than the trials tyres from the mid 1970s so it should be expected that if you still are using the original mudguard mounts, there will be less clearance

Ok I will try this piston. ...found some details on the bike which are not original, but from the 70ies, the rear mudguard was not original, but M.Robert. Front mudguard NAVA, some italian i think, levers magura, but special short ones. Handlebars are original i think as well as amal throttle. --swing arm was bent, I replaced and converted the brake lever to the right side. finally found a white used plastic mudguard ... thats it for today...

 

Hi again, last week I put together the whole stuff. the plan was to finish that project this year. I have put on the replace cylinder with the piston i found in my shed, new tires, oils, chain, front sprocket 11, new dellorto carb 28, new grips, filter element,new gas shocks, new chain guard alloy, rims blasted with glass pearls, the rest cleaned up.

..and it runs great. The engine goes very smooth and powerful.

here some pics of the project...totally worn slide from bing, new Dellorto (would never use Bing again) ,upper frame connection without hole (forgotten at the factory), left side nearly finished, right side with brake conversion, worn footpads before and after welding,

and last not least ...first run outside. wish you all a Happy new year...