johnjsy Posted May 25, 2016 Report Share Posted May 25, 2016 Piston size on what did you do to your Bultaco today Quote Link to comment Share on other sites More sharing options...
johnjsy Posted May 25, 2016 Report Share Posted May 25, 2016 Piston size on what did you do to your Bultaco today. Hi bultacorock,Mahle Pistons are all made to a nominal size,such as .50 oversize for instance. When finally machined they may be fractionally under or over size. The minus sign on yours indicates it is just a little under size. Each piston is carefully checked then marked before being boxed for sale.That is the marking you see. When a cylinder is sent out for re-boring the replacement piston needs to go as well so as the machinist can hone to a specified clearance. What you have discovered by accident is Bultaco quality ! Hope this helps,John. 3 Quote Link to comment Share on other sites More sharing options...
scot taco Posted May 26, 2016 Author Report Share Posted May 26, 2016 None as far as I know, the difference is in the primary gearing. These make great trials motorcycles with very few changes. Thanks for the reply.I,m not sure which way I will go with this project just yet,but a replica Sherpa T is one thought. 4 Quote Link to comment Share on other sites More sharing options...
johnjsy Posted May 26, 2016 Report Share Posted May 26, 2016 Hi Scot Taco,I have had a look at my listings for you. The Matador Mk 2, model M 16 gear ratios -0287...0482....0683..& 1 to 1 for top gear. The first Sherpa T,model M10, is-0350...0454...0831..& 1 to 1 for top gear. A fair bit of difference. If you had an idea to use the Matador for trials I would suggest just to find a M 10 motor in good order then swap over. The later Mk 3 Matador had a 5 speed box. Hope this helps,John. 2 Quote Link to comment Share on other sites More sharing options...
scot taco Posted May 26, 2016 Author Report Share Posted May 26, 2016 Thanks for that John.The m10 Sherpa motor is rare as hens teeth here.The more I,ve thought about it the more I,m leaning towards keeping it what it is. If I could find an early Sherpa S tank and high pipe I would maybe put those on it just because I love the looks of those. 3 Quote Link to comment Share on other sites More sharing options...
darmst6829 Posted May 27, 2016 Report Share Posted May 27, 2016 4 speed Bultaco's are great to mix and match parts. I built a 1966 Sherpa Scrambler with a Matador top end and a Mercurio close ratio gear box lower end. http://bultacoforum.com/index.php?topic=267.0 https://davidarmstrong.smugmug.com/My-First-Gallery/ I also ran a 1966 Matador 4 speed set up as a trials bike for about 7 years, only recently selling both the Sherpa s and trials bike to the same young guy. 1 Quote Link to comment Share on other sites More sharing options...
saw miller Posted May 27, 2016 Report Share Posted May 27, 2016 Dusted em off and went for a ride! 5 Quote Link to comment Share on other sites More sharing options...
saw miller Posted May 27, 2016 Report Share Posted May 27, 2016 My friend Alex on his 250. Quote Link to comment Share on other sites More sharing options...
saw miller Posted May 27, 2016 Report Share Posted May 27, 2016 Oops. 5 Quote Link to comment Share on other sites More sharing options...
scot taco Posted May 27, 2016 Author Report Share Posted May 27, 2016 4 speed Bultaco's are great to mix and match parts. I built a 1966 Sherpa Scrambler with a Matador top end and a Mercurio close ratio gear box lower end. http://bultacoforum.com/index.php?topic=267.0 https://davidarmstrong.smugmug.com/My-First-Gallery/ I also ran a 1966 Matador 4 speed set up as a trials bike for about 7 years, only recently selling both the Sherpa s and trials bike to the same young guy. Dave, Those two Buls that you built are pretty cool! They are hard to beat because they are so easy to work on and you can mix and match a lot of different parts. After seeing the photos I recognize you and the MXer from the Hammer and Tongs site.It seems like you guys have a good vintage following out there. Thanks for the links. 3 Quote Link to comment Share on other sites More sharing options...
scot taco Posted May 27, 2016 Author Report Share Posted May 27, 2016 Tripp, I had to look twice to see who was riding your bike. No whiskers! 2 Quote Link to comment Share on other sites More sharing options...
saw miller Posted May 27, 2016 Report Share Posted May 27, 2016 Had to do some work at Solvay Polymers. No beards allowed! 3 Quote Link to comment Share on other sites More sharing options...
scot taco Posted June 7, 2016 Author Report Share Posted June 7, 2016 I was actually able to get out and ride it over the weekend although I did end up on the Ossa for most of the time because my brother was more at home on the Bul. 7 Quote Link to comment Share on other sites More sharing options...
chappo Posted June 18, 2016 Report Share Posted June 18, 2016 Finally got round to replacing the foot pegs on my 198a. Cut the originals off leaving the outline of originals so the welder could get a measurement, they have actually gone back 5mm and down 10mm, not much of a change. Just primed the metal hangers and surrounding exposed frame, ready for spraying tomorrow. 3 Quote Link to comment Share on other sites More sharing options...
bondy Posted June 19, 2016 Report Share Posted June 19, 2016 (edited) Nice job hoping to get 2 off mine done. Edited June 19, 2016 by bondy Quote Link to comment Share on other sites More sharing options...
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