lineaway Posted August 8, 2014 Report Share Posted August 8, 2014 Did you not ride it before you bought it? It would be a hard bike to ride if you did not compete in the 70`s. I never liked the Sherpa t`s, was an Ossa fan and really like the late model Cota. (330,350) Had a Cota 200 that rode great, just did not have the power once our vintage club went to larger obstacles for the hard line. Quote Link to comment Share on other sites More sharing options...
guys Posted August 8, 2014 Report Share Posted August 8, 2014 Beta forks with a disk now that's a good idea ride it in the twinshock class sit back and watch the old farts whinge " Meanwhile, thousands of other people have not fitted different forks to their Bultacos, and continue to get great enjoyment from riding them that way" Am I not allowed to be different ? its my bike my money and my time Nobody said that, just that a lot of people are happy with the original forks Quote Link to comment Share on other sites More sharing options...
taff_d Posted August 8, 2014 Author Report Share Posted August 8, 2014 (edited) Did you not ride it before you bought it? It would be a hard bike to ride if you did not compete in the 70`s. I never liked the Sherpa t`s, was an Ossa fan and really like the late model Cota. (330,350) Had a Cota 200 that rode great, just did not have the power once our vintage club went to larger obstacles for the hard line. The bike was a non runner when I went to see it, all there but just would not run, I bought it cheap (stole it really ) got it home cleaned the carb fresh fuel and she started but ran like a bag a s***e. I have rebuilt the engine and split the exhaust re-sleeved and packed it and had both shot blasted and painted so the engine and exhaust are spot on now apart from I dont like the slow pick up (but I have plans for that over the winter) The bike came with rock shocks so I have serviced them and re-sprung and shimmed to suit my weight and they work fine so it's just the front to sort now. I'm not bothering doing up the frame as I want to ride it not look at it and be upset if I crash and damage it (which I will on a regular basis). Might put a alloy swinging arm on it to save weight and change out as many heavy steel parts as possible. I did not ride trials till 4 years ago so no I never competed in the 70's Edited August 8, 2014 by taff_d Quote Link to comment Share on other sites More sharing options...
lineaway Posted August 8, 2014 Report Share Posted August 8, 2014 Even better! I always love projects. I thought it sounded like the twin shock was a new adventure! I`ve competed in several vintage events on Bultaco`s. They are better to look at than to actually ride. Just my opinion. Quote Link to comment Share on other sites More sharing options...
guys Posted August 8, 2014 Report Share Posted August 8, 2014 The bike was a non runner when I went to see it, all there but just would not run, I bought it cheap (stole it really ) got it home cleaned the carb fresh fuel and she started but ran like a bag a s***e. I have rebuilt the engine and split the exhaust re-sleeved and packed it and had both shot blasted and painted so the engine and exhaust are spot on now apart from I dont like the slow pick up (but I have plans for that over the winter) The bike came with rock shocks so I have serviced them and re-sprung and shimmed to suit my weight and they work fine so it's just the front to sort now. I'm not bothering doing up the frame as I want to ride it not look at it and be upset if I crash and damage it (which I will on a regular basis). Might put a alloy swinging arm on it to save weight and change out as many heavy steel parts as possible. I did not ride trials till 4 years ago so no I never competed in the 70's I've mounted a 1.1 kg lighter electronic ignition rotor which also has a smaller outer diameter on my T350, which makes a lot of difference. Quote Link to comment Share on other sites More sharing options...
taff_d Posted August 8, 2014 Author Report Share Posted August 8, 2014 (edited) I've mounted a 1.1 kg lighter electronic ignition rotor which also has a smaller outer diameter on my T350, which makes a lot of difference. where did you get that from ? I intend to take the clutch side weight to work and machine quiet a bit off that to lighten it which should make it spin up faster. Edited August 8, 2014 by taff_d Quote Link to comment Share on other sites More sharing options...
guys Posted August 8, 2014 Report Share Posted August 8, 2014 (edited) where did you get that from ? I intend to take the clutch side weight to work and machine quiet a bit off that to lighten it which should make it spin up faster. That would do the trick also. But I'm lazy so: http://www.francetrialclassic.com/en/ignition/1280-bultaco-trial-electronic-ignition.html Edited August 8, 2014 by guys Quote Link to comment Share on other sites More sharing options...
taff_d Posted August 8, 2014 Author Report Share Posted August 8, 2014 I've got electronic ignition on it already I just need a lighter flywheel, best do some research this trip away with work. Quote Link to comment Share on other sites More sharing options...
woody Posted August 8, 2014 Report Share Posted August 8, 2014 To save machining the clutch weight (it's supposed to be difficult as they are hardened but I'm no engineer, just what I've been told) you can fit the clutch weight from a 250 which is a single weight, not double. Also, you can fit a 250 ignition flywheel which is lighter than the 350. If you fit both, pick up will be very quick but the motor will stall a lot easier Just fitting the 250 ignition flywheel will quicken pick up but the 199a shouldn't be that lazy anyway. I think the electronic ignitions have more retardation at low revs than they really need, especially when built for a purpose made trials bike which had the right power delivery (well, most did) from the factory by engine/porting design. The bikes that benefit most from the revised advance curves are Pre65 4 strokes as they were never made as trials engines. 200cc is too much for the Bultaco forks, you'll lose travel through hydraulic affect, but it's up to you if you want to continue with it. Fantic forks only use that and they are over 2" longer, plus, look how short the Bultaco legs are. They are basically the same fork as the Ossa but the Ossa had longer legs and the most they take is 180cc. I mentioned why they may be topping in my previous post, and the affect of fitting different forks, all of which are longer. 1 Quote Link to comment Share on other sites More sharing options...
woody Posted August 8, 2014 Report Share Posted August 8, 2014 Change to the Alpina or Pursang style stem. Just the stem? Can't see how this helps as the yokes have the rake built in, or do you mean the entire yoke assembly from the Alpina / Pursang (only certain years work) They are parrallel as opposed to the anngled Sherpa yokes but the spacing of the forks is wider which means new spacers have to be made for the front wheel and I'm not sure how the Sherpa mudguard brace will cope with the extra width. I think the lock stops may present an issue too. I was going to try it not too long ago but didn't bother in the end as the hassle wasn't worth what would have probably been a minor and barely noticeable improvement Quote Link to comment Share on other sites More sharing options...
taff_d Posted August 8, 2014 Author Report Share Posted August 8, 2014 (edited) To save machining the clutch weight (it's supposed to be difficult as they are hardened but I'm no engineer, just what I've been told) you can fit the clutch weight from a 250 which is a single weight, not double. Also, you can fit a 250 ignition flywheel which is lighter than the 350. If you fit both, pick up will be very quick but the motor will stall a lot easier Just fitting the 250 ignition flywheel will quicken pick up but the 199a shouldn't be that lazy anyway. I think the electronic ignitions have more retardation at low revs than they really need, especially when built for a purpose made trials bike which had the right power delivery (well, most did) from the factory by engine/porting design. The bikes that benefit most from the revised advance curves are Pre65 4 strokes as they were never made as trials engines. 200cc is too much for the Bultaco forks, you'll lose travel through hydraulic affect, but it's up to you if you want to continue with it. Fantic forks only use that and they are over 2" longer, plus, look how short the Bultaco legs are. They are basically the same fork as the Ossa but the Ossa had longer legs and the most they take is 180cc. I mentioned why they may be topping in my previous post, and the affect of fitting different forks, all of which are longer. Cheers Woody much appreciated, bikes packed away again as I'm back offshore Monday so I'll spend my nights away trawling ebay for a 250 flywheel and clutch weight. I'll remove the forks and totally strip them and check for damage when I get back, and I intend to rebuild using magical springs and caps. For info the clutch weight is case hardened and it can be machined quite easy using carbide tips, once underneath the hard outside skin they are soft cast steel. Edited August 8, 2014 by taff_d Quote Link to comment Share on other sites More sharing options...
smelling123 Posted August 8, 2014 Report Share Posted August 8, 2014 The alpine yolks are parallel and will steepen the forks but increase the trail - so make the steering slower 1 Quote Link to comment Share on other sites More sharing options...
smelling123 Posted August 8, 2014 Report Share Posted August 8, 2014 The magical springs are excellent, Quote Link to comment Share on other sites More sharing options...
woody Posted August 8, 2014 Report Share Posted August 8, 2014 For info the clutch weight is case hardened and it can be machined quite easy using carbide tips, once underneath the hard outside skin they are soft cast steel. That's good news as I wanted to make the weight on my 250 a bit lighter. A phone call to my engineer friend I think... Quote Link to comment Share on other sites More sharing options...
taff_d Posted August 9, 2014 Author Report Share Posted August 9, 2014 That's good news as I wanted to make the weight on my 250 a bit lighter. A phone call to my engineer friend I think... I bought a spare clutch weight off eBay for £3 when I first got the bike meaning to machine it down but never got round to it. I have just dug it out the garage and weighed it 9lb its way to heavy for me to get offshore in my kit bag so I've dropped it at a local bloke who has a lathe in his garage and he's taking 10mm aside off the diameters and 15mm off the front face. Quote Link to comment Share on other sites More sharing options...
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