thai-ty

Identical in every way, bar the paint jobs. Steel tanks, frame brackets cut and basically converted from S to R spec. Lowered, straight down, not back, wider footrests. Shortened steel kick start lever. Modified custom k/start stop. Grease nipple added to rear brake lever. Drilled bash plate. 6" Renthals. Talon sprockets, steel front, alloy rear, stock '84 gearing 10/42T. Lots of stainless fasteners, allen heads tapered, hex heads faced off and made concave to lighten. Stock TK carbs, bar bigger main jets. Stock air filter lid snorkel removed, and lid opened up on the milling machine. Boyesen dual stage power reeds fitted and the recommended Boyesen reed cage mod done. Stock ignition and full flywheel weights fitted. Exhaust header burnt out and cleaned, exhaust mid box, cut, cleaned, burnt out, recleaned. repacked and gas welded back together. New DEP alloy silencers fitted. Made in Thailand new fiberglass rear mudguards. New paint, decals and seats recovered. Dry weight, no fuel, no oil, 85 kgs. They go as well as they look.

My two 1984 Yamaha ty250 Mono's.

John Cane @ Ty Trials has the airbox lids, jets and jetting recommendations. All on his website.

Yep, 38 years and counting...

I've just got a new 'puter, so still have not uploaded my photos that I saved from the old laptop. When that happens I will remove most of the photos in this thread and start a new thread with a couple of photos of the finished article(s). If anybody is interested in the build inc a large amount of photos inc cutting, cleaning out, repacking and gas welding shut the mid box etc etc, you can read about it in a general Thai centric forum, runs to 12 odd pages last time I looked. Google; Thai Visa Forums Motorcycle forums The Tale of Two ty250 mono's (pic heavy) Regards, Mike.

Hi Andy, these days he is extremely busy and can pick and choose his jobs, unlike a few years ago, so in short, no. They come in an army type olive drab colour from the moulds and recquire some filling and prep work prior to painting, cost approx. A$ 52 each so not particularly cheap. These came free with the bikes, if (when) I had (have) to buy new again i'd just buy new plastic mudguards in the UK, readily available, ready to bolt on for 60 odd quid. Less with the VAT. Front and rears are still available. Regards, Mike.

Before Brexit and the Pound's collapse, the price would have been 155 quid....

Why thank you kind sir. Over 300 views and I get a reply! The bike is a 1979 Triumph T140E Bonneville, owned from new by me, one owner. Motor has been through many sizes from stock 750 to as big as 870 (liners too thin, kept distorting and seizing), currently 830cc. Anywhere between 803 and 840cc is super reliable. Been through many incarnations including a rigid frame and single carb head between 82 and 89, and it's current look was built around 94-95 as an advert for my then Triumph shop in the UK. Main claim to fame internally is a very rare, very expensive, very very heavy Weslake stroked full circle crank with Carillo conrods. Externally obviously the modified nickel plated frame with the competition Hunt magneto hanging off the side. She goes as well as she looks....

Oh. was just about to post 4 more photos, but apparently, i have used up 89% of my attachment allowance. So, at the mo, no more pics of the rebuilds. in which case not a lot of point with any more descriptions...

Been late posting. Life, farm, rainy season got in the way... I'd already decided the colours and paint jobs. The two bikes were to be called 'Ol Yeller and 'Ol Blu. Both just had to have trad Yamaha Speed Block decals. 'Ol Yeller was straight forward, yellow cycle parts with black rolling chassis. 'Ol Blu was initially going to be a silver rolling chassis with a pale, sky blue type cycle parts, early ty250 twinshocks in the States and early DT series bikes had this colour. But i realized there was not enough contrast there, so after trawling the net looking at 70's-80's trials bikes, i realized i love that late Bultaco blue with a white chassis. 'Ol blu would be my Yamaha homeage to the old Buls. Went to see my painter man, lovely old boy, Mr. Udom who runs an auto body repair/paint shop in town. He has two sons, both mad for it 2 stroke drag bike racers. One works for him, the other has his own paint, body repair shop dealing purely in insurance work. Mr Udom does all the private stuff. We agreed a price of 4000 Thai baht for each bike, 4 colours, 8000 Baht in total. Equates to around £185 total at the current crappy rate of exchange. We agreed one colour a week, spread over 4 weeks so as not to confuse him, and allow his other work to continue.

So i'd put weight back on with those 8mm thick footpeg brackets, now it was time to get out the hacksaw and 4" angle grinder with cutting discs and remove some weight. Below is everything chopped off two frames including two steering locks.... Two S frames are now identical to my one R frame (bar one small flat bracket that locates the front of the airbox).

So it was time to strip the bikes out. I'd decided to use 2 of the S frames and copy all the lack of brackets off the one R type frame i had. First job was cut the stock footrest mounts off and throw the narrow stock pegs in the bin. Metaphorically speaking.... Bought some 8mm thick plate, made my cardboard templates, shaped said plates, drilled and tapped, for my modified stock clevis and mig welded them pretty much straight down, maybe 1/4" back, not more. I reckon they are 1.5 - 1.75" down from stock, but still above the sump guard / bash plate. Clevis are held on by 8mm HT c'sunk screws thru the brkts, no welding. So far, held up well, and easily repairable. I'm a lanky bar steward at 6' 3", and before it felt like i was riding on the bike rather than in the bike, that little difference in height made such a difference to me, they are also twice as wide and much more comfortable.

When i bought the bikes i also bought 4 new tyres and tubes off the guy, 2 Vee Rubber rears, and a couple of Siam unheard of brand fronts. But the price was right. Difficult to get trials tyres over here. The VEE Rubber rears look nice tyres and seem pliable and soft. Back in Thailand i'd bought new 520 chain, a big bag of stainless fasteners for all the easy replaceable bolts, nuts and washers for £35, a couple of very nice throttle sets i'd used before, sort of medium action. Complete throttle housing made out of alloy, nice bearing, lovely pair of grips and a custom cable where you solder the carb slide end on. Nice bits of kit for, er, £6 each, A couple of RXZ Yamaha petrol taps, identical to ty, bar they are handed wrong, ie spigot faces the wrong way, but at £2 each i'm not complaining. Bought 4 new forged h/bar levers to suit the stock Yamaha perches for about a £1 quid each, 15 minutes with a file and they fit perfectly. Bought two s/arm chain protector rubbers off some Grom type thing for another £1 quid each, a bit of time with a Stanley knife and they fit well, and i had most of the parts there, bar a monthly order abroad for stuff over a 4 month period of time. I will not use couriers (DHL, Fed Ex, UPS et al) as they are just complete rip off thieves this end when it comes to import tax and customs. Get a bad one and it can be 100% mark up or more on the value of the goods. UK, and US postal services, registered, fine, no problems, still pay tax, but it's acceptable. If the parcel can be kept below 2 kgs in weight, then postage is very reasonable. So it was Boyesen reeds direct from Boyesen in the States, and a couple of DEP alloy silencers from Sammy miller Products and some clutch and brake cables from TY trials.

You can pick up a tatty mono in running condition for an average price of £600, generally being used as a trail bike on the islands. About one a year shows up on the ads. A couple of Honda TL's and TLR's occasionally show up, priced around £850, and every year i see a couple of modern trials bikes advertised, 8, 10, 12 y/o Gas Gas, Shercos, Betas for around £3k for a shiny tidy one. I bought these 4 from a very nice, knowledgeable Belgium guy, they were the very last of his 2 strokes from his quite unbelievable collection.The nicer ty 250 monos he'd sold individually over the years to his local friends. He still had well over a dozen various Hondas which he was slowly whittling down.

I would have liked 2 plastic tanks, then i could of bought two of Paul's Shedworks shelters. But i only had one, so it was steel tanks (at least i can get them painted...) and seat bases. Guy in Chang Mai has a very well known fibre glass shop, makes anything from a sample. I got quoted £20 for a mold and £15 thereafter per seat base. Not bad. I already had 3 of his rear mudguards and one front. After mucho work with a bunch of body filler i was able to salvage two seat bases from four. The other 2 were scrap. As was a bunch of std Yamaha 30 odd y/o plastics. Went to the UK for a couple of months in Oct/Nov 2016 with a big shopping list, two of everything. 6" Renthals, Talon front and rear sprockets, air filters, s/s cover screws, s/s reed valve screws, s/s float bowl screws, gaskets, fork seals, fork bushes top and bottom, chain tensioner pads, 1 x chainguard, modern wider footrests and weld on brkts, etc etc. Bought from BVM Moto, In Motion, Yam Bits and Ty Trials. Would have liked to buy most from John @Ty Trials, but he was in the middle of his nightmare shop move at this time. I love the fact that you can get stuff for these bikes, genuine or remade aftermarket, easier in a lot of cases than more modern stuff. Brilliant. Try getting a 15 y/o Beta m/guard.... 33 y/o Yamaha - no problemo...

This is the worst rim. Photos do not do justice to just how bad the rim corrosion is.

So checking stuff out, i've got 2 slightly pitted prs of useable forks, dimensionally on size, one pair that look great but are well under size and decoratively rechromed (damn) and a pair that need a full on regrind, re hard chrome and ground to size (UK suitcase job). A good nice quite motor, a rattley motor, turns out a wobbly s/end bearing, but running a 16mm pin (stock 18mm) in a std bearing with a 1mm hardened sleeve. Piston is identical in every way inc the 2 windows EXCEPT pin hole size. Weird. And 3 spare motors with no pistons in them , conrod flapping about in the bore.... Also got 3 nice new fibreglass made in Chang Mai Thailand rear mudguards. 2 pairs of good wheels, i pair useable, and 3 corroded to hell, plu a couple of hubs and brake plates.

Back home decided what was what. What was good and bad. Got a second one running and rode around a bit last year deciding what the bikes needed. Was'nt going to be cheap, modify, make, paint, and buy two of everything... My idea was to build two nice ones from the four, both identical bar the paint jobs, and so i'd have 2 bikes, one of which my son could learn on with me. And a bunch of spares left over.

In February 2016 i spotted an ad on the net, about a day's drive away for a set of 4 (four) Japan market 1984 ty250 monos plus spares. Had to borrow a pick up and drive there and bring them back. Paid about £820 for the lot. 3 S models and 1 R model, one even a decent runner, and useful spares inc a 5th motor. 3 steel tanks, 1 plastic tank and a majority of the plastics turned to dust. Amazing what UV does...

Hi guys and gals, TC newbie here, English bloke living in NE Thailand. Long time lurker, gleaned lots of tech info over the last couple of years, thought it might be time to join. Sold up and moved here in 2003, brought my containers, workshops and bikes over in 2005. Had road bikes all my adult life (16-56), had a m/c business in the UK from 1988 -2003, and have got into trials bikes the last couple of years. Always liked the look of 70-80's twinshocks and the air cooled mono's. Started off with a Yamilia, Aprilia Climber rolling chassis with an RXZ135S Yamaha air cooled motor bored to 142cc. Soon outgrew that, sold it, and bought a set of 4 (FOUR) Japan Market 1984 Yamaha ty250 monos with the idea of building two nice ones from the four. Just finished them. I will post some pics and details in the relevant forum sections. Around this part of Thailand there is no trials scene whatsoever. So i have to play by myself. (!?) The big thing up here is modern motocross bikes. There is a fairly lively trials scene in the NW of the country, but that is a good day's drive from here, think London-Glasgow. I have 25 acres of land around and near the house, with some good climbs, gulleys, rocks etc, so plenty of practice and riding on my doorstep. I am thoroughly enjoying learning new set skills, balance and throttle control, but at my age i aint gonna be the next Lampkin. I'm also not that interested in the modern trials or latest bikes, much as i admire the unbelievable and jaw dropping skills, it does'nt do that much for me. I certainly won't be learning, zap, double zap, hop, scotch and jump stuff. Regards, Mike.