kevin j

since you said $50, I assume you are in the US? Prices of TY80 dropped dramatically about 5-8 years back as the modern kid bikes started to to get into the used pipeline. When I was looking fo my kids in the late 90's, the TY80 was the only option for kids to learn on. $500-800 was common, with most club 80's having a waiting list as to whose kid gets it next. I grabbed up any scrap 80 parts I could get. By the time my kids outgrew, I sold one really nice one for $500. Still have another pretty nice one to sell, but I don't want it sold as kids 'dirt bike' where it will get trashed, so it sits in storage. The modern water cooled ones are way better bikes, and lower seat height, lighter weight, less parent maintenance required (although the 80 is way simpler and cheaper to work on) anyway, my reason for that is, unless you are doing it for nostalgia reasons, or for a parent child project (keeping in mind kids have less patience and grow faster than the project might get done), or as a fairly simple learning project for yourself, it may not be cost effective to fix it with new stuff and paying for crank rebuild. IF the body work is good, I'd watch for a bottom end or parts bike or engine and go from there. The GT and MX models are similar parts. Heads and cylinders and flywheels and carbs are different. The engine is easy to split. Change out the entire crank, bearings are <10 each at industrial supply houses, most seals (except the clutch pushrod) also industrial supply. Wisecon pistons and rings (except pins and small bearings I think had to source Yamaha), Vesrah gasket sets from dennis kirk were cheap. MX/GT gasket sets had different head gasket hole diameters, but can work in a pinch if the TY set is not available. Tough little bikes, kid friendly, and beautiful lines I think, especially the later tank with the TY175 style paint. Many good memories there. kcj

just for future ref don't know about the left, but the right side on mine popped partially out a couple times. Vast clouds of ATF from gearbox being burned. as a short term fix I pulled the cover and pressed it back into place until later changed engines. Long time back, but I assume at least the right side could be pulled with a slide hammer tool and replaced fromt he outside. good you got it fixed much easier though. k

are you sure it is top end? lean it 45 degrees to left, then to right. does it change? I have a 2000 200 that has nasty noise. top end rebuilds, new mains, not solved it. come to find out the crank moves left and right in the bearings. The helical gear pushes one way on compression, then load reversed when cylnder fires and it walks the other way. Tore down, used high temp red loctite on one side. lasted about a month, let lose, noise is back. Nothing excessively worn, just terrible noise and embarassing. And it will wear the crank journal eventually. Now I have .014 inch of axial play. Next step is R&R and add some shims from Grainger between main bearing and crank shoulder. kcj

I have an OEM rubber spid plate pad. Told it was for a TR34. will it fit the others? If someone wants it, PM me I will ship it. US preferred. you donate freight cost to TC. Ryan: check www.umta.org. first event is late April in Thielman near Winona MN so some IA guys usually come up. kcj

questions: -if you lived in FLA and want a cheaper car, would you deal on one in dubai? -If you wanted to sell a car, would you be dealing on shipping one to dubai? -If you wanted a cheaper car, might you have some more questions for the seller than what he is asking? -If you wanted a cheaper car because of impending economy, might you not want to move downscale more than $3000? I will bet if you send the 3000 to him, he will arrange shipping his car to your house, and arrange shipping your car to his house. No hassle, he takes care of it all. In otherwords, SCAM.

use a handful of sheet metal screws for hvac ducting. #8 self piercing by 1/2 long. because I have tons of them. The hardened and sharp edges and points do a nice job cutting the rust. much better than nuts and bolts and I presume better than rounded gravel stones. I use the acid etch metal prep solution in the tank with the screws, and shake shake shake. personally i like the kreme coating if done right. inside must be totally dry, and acetone washed, for it to stick. all in the kit, just follow directions carefully. k

pai to access. I had to remove the skid pan each time. Rear mounts on the frame are prone to stripping out the threads, and no room for a nut, so I did not want to remove those bolts any more than necessary. I slotted the skid plate enough to get a ratcheting gear wrench up from below. much easier now. kcj

I would bet on the cable routing. Do you have slack in the housing when supposedly at idle? if not, the cable is lifting the slide. Also check the slide. On one side (I think right side) there is a brass pin in the carb body. The slide has a slot that fits on the pin to index it as it moves up and down. Been many years ago, but on two of mine, the pin worked its way outward and allowed the slide to turn slightly and bind on the pin. Solution: Lift the slide out, tap the pin gently inward so the outside is flush with the outside of carb body, and put a drop of epoxy on the outside. Clean and burrs on the slide, reinstall and it should be good. kcj

some injected systems moved oil into the main bearings, some had mains lubed from transmission oil. Most of the air cooled older stuff just dump the oil into the inlet after the carb and let it mix as it is thrashed around on the way. The oil slings out, collects on cylinder walls and funnels to the proper spots. All the TY just dump it into the intake, so you are fine to remove it. good to check it out first though. k

I may have a pump or two. If so, you pay shipping, pump is free. I will check this weekend. If you want to restore, replace the pump and keep original. for a rider, pull the pump. Less hassle, known lubrication, idles and runs cleaner, and lighter throttle cable pull. Can't just remove the cable as then the pump will continue to add oil at idle and idle will be double oiled (some in premix, some from pump) leading to fouled plugs. Pulling hose and cable works, but eventually the pump without oil can seize. You can loop the output hose from pump back to tank somehow. Easiest is to remove side covers, remove pump and gear drive (have to access that from inside the cover) and make a small alum blockoff plate for pump pad. Make a rubber pad to fill the space the cable exited the case. Solder or epoxy off the oil fitting on the cylinder inlet. Pull the oil tank. Then, make new throttle cable. the TY 80 are so small and have a light carb spring. Oh, by the way, the index pin on the carb body, that keeps the slide from rotating, can work loose. If it moves outward, the slide can snag and bind. The light spring can't overcome the friction to close the slide, causing exciting high idles (for example 3/4 throttle....). The drag of the heavy cables aggravates that. Make sure the pin is in place properly and put a dab of epoxy on the outside of the carb to hold the pin alignment. To return properly with good throttle feel I used universal cable housing, and bicycle brake wire coring. Very light and flexible. Solder the ends on with a dip pot made from a 3/4 inch copper tubing cap on a small bolt/stick for handle. I used Domino throttles. Removing the extra cable to pull the pump, the friction in the junction block, and lighter cable made the throttle much smoother and predictable. had three over the kid years. lots of maintenance as they were old bikes, but simple to fix and durable and great memories. Still have the last one, but will be selling off complete bike and quite a bit of drive and chassis parts. some plastic, a late model top yellow tank I think, and one new tire, rear I think. need anything? k

Don't believe every slant from the news! The people buying guns go through all sorts of hoops. They are the honest ones, they are NOT the ones you need to worry about. By definition, the ones we worry about are not the ones buying them legally at reputable shops, and will not do so no matter how many additional regulations the new regime will add on. And I worry more about muggers with knives, not guns. k

clamp baseball cards to the frame with clothespins to hit the spokes..... I would have done almost anything for a Honda 50 or 90 then. k

whatever happened to the 'Tork Attak" I think it was? almost full sized, and electric.

ok, loaded to photobucket, now how do I psot pics or links here? pdf of bracket dimensions I cannot load here. kcj edited 22 Oct (pics are dark, tried to lighten a bit) THANKS DAVE! learning something every day. overall view bracket inside view, bracket floating on axle and slotted to the fork leg lug.

The notes document in Word .doc format sketch is not posting well. Add also the pics in dig pic file, and the pdf of the CAD dwg. GOAL: -Disc front brake for Yamaha TY250/350 monoshock, 1984 to 1986 ORIGINAL PLANS: 1. Disc kits from that era. Brembo, Talon, etc. Either aftermarket conversion, or front end from TYZ in the 90's. Adv: made to fit Disadv: impossible to find. Obsolete for parts, and they are 80's technology. Some were not any better than the drum. 2. Fit fork tubes from disc brand of that era; Adv: may be easier. Disadv: Fork tube diameter did not match any of the disc brake parts. 3. Fit entire front end from a disc 80's bike (Fantic, montesa, etc.) Adv: ?? Disadv: hard to find, major project including machining, and geometry could be all hosed up with frame angles vs the front end angles from another brand. 4. Fit MX hub and disc Adv: parts available Disadv: heavier, have to lace up a wheel, much work, disc is much larger, and caliper is often behind fork tube where it can be damaged in trials. 5. Weld caliper mount to fork leg. I can't do it, it may destroy the leg, and cannot be converted back. 6. Epoxy the bracket to fork leg? Commonly done with the kits. Must be perfect fit to work. 7. Clamp a bracket to fork leg? Commonly done with the kits. Must be perfect fit. All of these were dead end paths for a couple years. Then, while moving around some spare wheels for the modern bikes, I thought, what if. . . . Ultimately, the GasGas front wheel and disc were far easier to fit than I ever imagined. All parts used for this were from 99-2000 GasGas trials bike, maybe common to later TXT also? I used the 4 piston AJP caliper and master cylinder. This caliper loads the pads from the top, with one single holding screw, without removing caliper from wheel. This choice was accidental, as they were the parts I had on hand and they fit well. Others would likely work also. 98 & prior used 2 piston calipers, but would probably work also. Older (and newer) 2 piston AJP calipers have to be removed from the wheel to change pads by pulling them out the bottom. That fact alone would sway me to the 4 piston parts. However, Travis' 96 with 2 piston caliper has stiffer and better brakes than the 4 piston ones, so I would recommend doing this conversion with any wheel and brakes available. I also used the GG wheel, disc, disc plastic guard, caliper mounting bolts, master cylinder, hose, etc. and the Yamaha axle. Original fork leg can be refitted with the drum brakes if the bike is sold, or if I need to rob the parts back for the modern bike. The caliper mounts on a plate the fits on axle on inner end, and takes the torque reaction through the original fork lug for the drum brake. GG wheel hub has floating disc, so the caliper mount is not so critical. Trials specific disc is very light and small. I would like to try this with a later model wheel with the smaller yet wave rotors. Total project took LESS THAN 5 HOURS for the prototype (not including turning spacers). Should take less time with these instructions, and is an incredible improvement for the time spent. I have a welder. A mill would be nice, but I did all work with hand tools and electric drill. BRACKET -I have dimensional sketches but cannot scan at the moment. I am trying to put into cad. -Disadvantage: the bracket is steel, because I can weld that. It is heavy. I would prefer to machine one from aluminum, Second choice would be to weld up the steel parts as shown, then machine the caliper mount pads for more accurate locating and square mount. -Bracket is a flat plate .188 inch thick. A hole at bottom floats on the original Yam axle. Slot in the plate flits over the brake lug on the inner side of left Yam fork leg. This takes the torque reaction. The Yam axle tightens on the fork leg and clamps the bracket between spacers and fork leg. Bracket does not move at all. -Around the axle hole is a stack of washers .285 thick, tack welded to the plate. -Along front top edge of plate is a flat 1/4 x 1 x 3 long. Two bosses weld to that to mount the caliper lugs. Bosses are 3/4 OD shaft material, .700 to .725 long. .352 hole to fit 8 mm bolt is drilled through the boss offset .050 to .065 from the center of the round shaft. This produces a drilled hole a bit offset from center, to locate the holes close to the flat bar. This offset was necessary for the brakcet parts to clear the curvature of the caliper casting. LOCATION -Wheel was originally about 6 mm to the right of being centered in the forks. While I could not feel this in handling, I know it has an effect. -I removed the (6) hex head disc mounting screws, kept the small cup washers in place, and used (6) M6 x 1.00 thread x 20 mm long button head allen screws. My local hardware store had them in the assortment drawer type displays. The thinner heads gained 2 mm in space. I also trimmed about 1 to 2 mm off the original brake lug on the left fork slider, on the inside edge. I trimmed only in the area the bolts will pass by, so most of the lug is still stock. The original drum brake backing plate can be refitted. -After this, wheel is NOT quite centered in front end, maybe 2 to 3 mm to right. This is not noticeable at all to me, but I think the wheel could be moved the last couple mm by adjusting the spokes and moving the rim to the left. Since it is not noticeable to me, I don't have the time to mess with the spokes, and the potential is there to make things worse not better, I just run it as is. The space and dimensions below match the final hub location. Adjusting the spokes would not change the spacer dimensions. SPACERS FOR AXLE AND BEARINGS -GG had aluminum axle, larger diameter than the steel Yamaha axle. -I used the GasGas aluminum wheel spacers (to fit the bearing ID)+ washers as noted to take up the left and right space. -Left side=GG spacer, .436 long + washer stack of (1) US 5/8 hard FW, + (1) metric FW + (1) machinery washer. Total stack of washers is .307 thick. -Right side GG spacer .944 + (1) 14 mm FW which is actually 15 mm ID and .104 thick. -Dim as noted below don't add up to the numbers above. I am not sure which is in error. I need to measure all parts again before having spacers machined to dimensions below. -Inside the ID of the GG spacers, but over the OD of the Yam axle, I used a copper coupling/splice for 1/2 water tubing, just because it was in the junk drawer. I cut about 1/8-3/16 out of the side making a C shaped bushing, and filed out some of the ID to fit the axle. By squeezing it inward, I filed and fitted it inside the GG spacers, and over the Yam axle. It's not perfect, but its not a100 mph application either. The original intent was a mockup to just see if the parts would fit. They fit better than I thought, so I went further to make it driveable. They worked great, I have ridden it for 2 years on the mockup parts. -What I have in now is a stack of washers to get the side to side distance correct, and some bronze bushings to fit between ID of the GasGas bearings and the OD of the Yamaha axle. I think another bearing will be available with ID to fit the Yam axle and OD to match the GG hub. I have not taken the measurements to my local industrial bearing supply house to find out, and probably never will. If I change bearings, the wheel won't fit back to the GG axle as a quick spare change. The washers and shims work fine, but it is a real pain when the wheel is taken off, with all the loose pieces to get out of order. I just haven't had time to have the spacers made from aluminum and verify the dimensions. -Crude dwg in Word. D1 is OD of the round alum shaft used to make the bearing. It is not critical. D2 is the turned down portion of shoulder. This is the ID of the wheel bearing. D3 is the ID through the spacer. It is the OD of the Yamaha axle. L1 is the spacer length between wheel bearing and the inside of bracket/caliper. L2 is the length inside the wheel bearing. It is not ciritcal. Break all edges and corners. Use aluminum. L1 D1 L2 D2 D3 Two spacers are required on the outboard side, one per bearing. One on the left (caliper) side, and one on the right side against the fork leg. The original inner GasGas spacer between the bearing inner races (inside the wheel) is used, and MUST be in place as it takes the axle load from tightening the axle in the Yam fork leg. Notes: 4/06. These dimensions don't match my sketches, Need to be verified before fabrication.

greek to me..... PM an address and I will send them email. kcj

May have some pics here at work... how do I post pics? tks, kcj

alum C & D tanks are quite hard to find. Steel ones on ebay are common. The larger 'trail kit' tanks are quite rare here. I may have a stock yellow AB model tank. I will check. Not sure if it has the rear bracket intact or not. PM me an email. Sold the twin shock 250's, so will be getting rid of the t/s stuff. I also have quite a bit of mono parts, and some TY80 and 175 to get listed here and sold off. kcj

Rather than weld or epoxy to the fork leg, I made a floating bracket that rode on the axle shaft, and had a slot that fit around the lug for the drum brake. The caliper bolted to that. (It was steel, as prototype, and a bit heavy. My intent was to make from aluminum after making necsessary changes. It worked great, and I never spent the $$ to have it made in alum.) The axle has some shims and spacers to fit the larger bearings, and to cewnter the wheel properly. I just used shim washers and bits of tubing, but dwg had the dim to make one piece spacers if you have a lathe. I posted pics on TC somewhere in the past. Search for those first please. If can't find, PM me and I will send pics and the scan of the bracket dwg. kcj

very little in common. seals and bearings as noted above. can't recall if the seal can be replaced from the clutch side from the outside, or if it is pressed from inside the cas.... worth a look before splitting.

Bob Ginder at B&J (bjracing.com) does a kit. I think it went to 192 or 195 cc. Several years back I was looking, he told me generally not really recommend it as it becomes much more noisy, less cylinder thickness and reliability, and not much gain. He recommended just overboring to the max, 180-185 cc I think. Bottom line, I just left it as is, did reeds and general port cleanup, nothing fancy. kcj

will appreciate hearing info on how you end up. I have a GG rear wheel asm that I am trying to fit to the Yam because of the tubelss tire. Disc brake is not really necessary, but is part of the deal as that is what the hub is. The snag is fitting the master cylinder for the brake, and lowering the pegs, without huge fabrication issues. k

where can I get the fibreglass tube protectors for a Rev 3? I use the neoprene socks for dirt and some rock ding protection, but the hard sided ones look like a good safety insurance. Couple guys here use them, but on GG. RYP doesn't list them at all. kcj

I had one years ago for daughter. Mine also had a Start/run switch that affected the timing. Must be in the start position, and would not rev up in that mode, thus could not start with WOT and cause the centrifugal clutch to engage and take off. Then, once running, it would die if throttle applied. Must move switch to Run, then it would accelerate and go. also had an exhaust restictor that plugged up, so tossed that. Just FWIW, the rear ring gear from a scooter QT50 is bigger (scooters were like PW drivetrain but bigger wheels, hence geared lower.) and gears the PW down better for slower speed and better torque/off road lugging. The scooter also had only one sided support bearing on rear axle. The axles were shorter, so could not just exchange the assembly. I just prssed out the axles and pressed the ring gear onto the PW axle and put it back, The pinion stays the same. In theory, gear mesh is slightly off, but these are just bevel gears, and they will still last forever. It wa s good modification for using the PW in trials youth situations. k

travel: yup, got to phone business hours today and talked to Ron. I've just never had the wheel off with fork brace released at same time apparently. Odd travel is normal. air box braces on the way. tks, kcj