Sounds like you've got a plan, and I applaud your efforts. Do you have a jig or a frame table you are going to use to make sure everything is straight or do you have another method?
I have a frame jig available for when I do the steering stem. The rest I'm not to worried about. I've worked it out in my head that I'll do the engine raise before I cut the bottom of the frame off.
Got my engine raised 1". first shot is the bottom rear mount cut and rewelded 1" higher. You can also see the bottom rails cut off. Some fab left to tie subframe legs back to bottom cross brace. These are the two new brackets I made to make up the 1" raise for the rear top engine mount. The front engine mount, I was able to use the stock mount plates. I just turned them up side down and reversed sides. then I cut the down tube in two places. Bent the upper cut towards the engine, and the lower cut back towards the front wheel. Then welded up. I will strenghten those areas with a diamond patch over each weld. This last pic is the clearancing of the top frame rail to clear the rear valve cover. I will blend out and the shape corners and add a fill piece. After all this is buttoned up and pretty, I'll tackle the rake on the steering stem.
This is not a complete conversion more a modification but fit here too I thing. I could get an old pair of betor forks from France: After deassembling there was some wear and the stanchions where a little bit pittet and not perfect straight anymore: The stancions where straightened again and got a new hard chrome plating. I then got special fork caps and progressive fork springs from Spain: The fork caps are adjustable: The lower fork tubes where lightened: Then I replaced some of the worn out shims and bushings too: And reassambled the forks, the main difference is to the standard one which are blue I lost about pound of weight because I can now use modern front fender brackets aut of alloy instead of the steel once. Then some paint: Test assembly:
Nothing to be envy for, actually I'am also a little bit impressed that it turned out so well, I think I've got a fork flash and this mod turned into a pimp my Bultaco ride. The mounts are from older GasGas, you can also take Sherco's from befor 2000. You have to get them first, just to know how much you have to turn down the lower fork tubes. I was inspired by the PUMA or Vasquez Bultacos, but these bikes where mostly rebuild with Paoli or other I do not know where they come from forks, (which are and will be far better too). I wanted to use the old standard Betor, these are cheap and easy to get. I took a pair for a low price, now I would not try to get the cheapest, better to get one which is in a very good technical condition. Without the corrections and chromeplating of the stanchions it is a really priceworthy modification and a good fork from a newer bike of the end 80' or 90's is as twice as expensive.
Got alittle farther along with my trials mods. I made the subframe much skinnier. After looking at the Peter Gaunt bike for a few more hours, I realized how they did it. First was to cut off outer down support from the shock mount to the outer swing arm mount tab. I refitted the down support by shortening the required amount and rewelded onto the top corners of the rear engine mount. Then I made two plates for either side and located the holes for the swingarm bolt, and used some smaller dia. tube to slide into the rear engine mount cross tube. These I welded to the bottom of the side plates. I also welded the footpegs on and made the rear brake lever pivot. Having lots of fun with this project. Next on the agenda is shorting the swingarm 1". Then I'll tackle the biggy, front fork rake.
Honda TL250 engine bored to 280. Frame looks to be one off custom. Here is a link. http://www.honda-trials.com/_sgg/m1ma_1.htm
Giving me ideas.. As if I need another project... This really isn't a conversion Other than converting a pile of bits into a trials bike....:huh So after a hunt though the storage /crap shed.. well I could build a trials bike from this one complete single shock rear end/ forks,clamps from a Chinese Shinray 200. Motor.. well after a hunt around for a used one I came across these...NO laughing..found a out fit that was all but giving away these new chinese 125cc Honda copys.. 4 speed box ,auto clutch power houses . So I ordered one:huh.. managed to flog a pic from this site of the specs.. rake/trail/wheel base etc of a gasgas .. Now 1st to build a jig to bolt all the main componets in at the right hights / angles etc.. then build a frame around them..sounds easy when yer say it fast.. just lucky I have more toys in the shop than yer can poke a stick at....lathe / mill / welders / plasma It will give my boy 9 and me a some thing to do on wet days..
The motor turned up .... looking at it...I think the best aproce is to make the engine plates & set the swing arm up on them..Prob the easyest way to get it all alined.... i think when the build starts I mite start a new thread for it... "with smaller pics" pete
Not on the bike....just got to get the side car done then its all go... side car build here.... http://www.advrider.com/forums/showthread.php?t=716993
